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Truman announcing the bombing of Hiroshima
President Truman announces the bombing of Hiroshima.
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Japanese realization of the bombing
The Tokyo control operator of the Japanese Broadcasting Corporation noticed that the Hiroshima station had gone off the air. He tried to re-establish his program by using another telephone line, but it too had failed.[24] About twenty minutes later the Tokyo railroad telegraph center realized that the main line telegraph had stopped working just north of Hiroshima. From some small railway stops within 16 kilometers (10 mi) of the city came unofficial and confused reports of a terrible explosion in Hiroshima. All these reports were transmitted to the headquarters of the Japanese General Staff.
Military bases repeatedly tried to call the Army Control Station in Hiroshima. The complete silence from that city puzzled the men at headquarters; they knew that no large enemy raid had occurred and that no sizeable store of explosives was in Hiroshima at that time. A young officer of the Japanese General Staff was instructed to fly immediately to Hiroshima, to land, survey the damage, and return to Tokyo with reliable information for the staff. It was generally felt at headquarters that nothing serious had taken place and that it was all a rumor.
The staff officer went to the airport and took off for the southwest. After flying for about three hours, while still nearly one hundred miles (160 km) from Hiroshima, he and his pilot saw a great cloud of smoke from the bomb. In the bright afternoon, the remains of Hiroshima were burning. Their plane soon reached the city, around which they circled in disbelief. A great scar on the land still burning and covered by a heavy cloud of smoke was all that was left. They landed south of the city, and the staff officer, after reporting to Tokyo, immediately began to organize relief measures.
By August 8, 1945, newspapers in the US were reporting that broadcasts from Radio Tokyo had described the destruction observed in Hiroshima. "Practically all living things, human and animal, were literally seared to death," Japanese radio announcers said in a broadcast captured by Allied sources.[25]
Post-attack casualties
According to most estimates, the immediate effects of the blast killed approximately 70,000 people in Hiroshima. Estimates of total deaths by the end of 1945 from burns, radiation and related disease, the effects of which were aggravated by lack of medical resources, range from 90,000 to 140,000.[4][26] Some estimates state up to 200,000 had died by 1950, due to cancer and other long-term effects.[1][27][5] From 1950 to 1990, roughly 9% of the cancer and leukemia deaths among bomb survivors was due to radiation from the bombs.[28] At least eleven known prisoners of war died from the bombing.[29]
Wednesday, February 25, 2009
The bombing
For the composition of the USAAF mission see 509th Composite Group.
Seizo Yamada's ground level photo taken from approximately 7 km northeast of Hiroshima.
Hiroshima was the primary target of the first nuclear bombing mission on August 6, with Kokura and Nagasaki being alternative targets. August 6 was chosen because there had previously been cloud cover over the target. The 393d Bombardment Squadron B-29 Enola Gay, piloted and commanded by 509th Composite Group commander Colonel Paul Tibbets, was launched from North Field airbase on Tinian in the West Pacific, about six hours flight time from Japan. The Enola Gay (named after Colonel Tibbets' mother) was accompanied by two other B29s, The Great Artiste which carried instrumentation, commanded by Major Charles W. Sweeney, and a then-nameless aircraft later called Necessary Evil (the photography aircraft) commanded by Captain George Marquardt.[18]
After leaving Tinian the aircraft made their way separately to Iwo Jima where they rendezvoused at 2,440 m (8,000 ft) and set course for Japan. The aircraft arrived over the target in clear visibility at 9,855 m (32,000 ft). On the journey, Navy Captain William Parsons had armed the bomb, which had been left unarmed to minimize the risks during takeoff. His assistant, 2nd Lt. Morris Jeppson, removed the safety devices thirty minutes before reaching the target area.[19]
Hiroshima, in the aftermath of the bombing
The release at 08:15 (Hiroshima time) was uneventful, and the gravity bomb known as "Little Boy", a gun-type fission weapon with 60 kg (130 pounds) of uranium-235, took fifty-seven seconds to fall from the aircraft to the predetermined detonation height about six hundred meters (1,900 ft) above the city. Due to crosswind, it missed the aiming point, the Aioi Bridge, by almost eight hundred feet and detonated directly over Shima Surgical Clinic.[20] It created a blast equivalent to about 13 kilotons of TNT. (The U-235 weapon was considered very inefficient, with only 1.38% of its material fissioning.)[21] The radius of total destruction was about one mile (1.6 km), with resulting fires across 11.4 km² (4.4 square miles).[22] Infrastructure damage was estimated at ninety percent of Hiroshima's buildings being either damaged or completely destroyed.
About an hour before the bombing, Japanese early warning radar detected the approach of some American aircraft headed for the southern part of Japan. An alert was given and radio broadcasting stopped in many cities, among them Hiroshima. At nearly 08:00, the radar operator in Hiroshima determined that the number of planes coming in was very small—probably not more than three—and the air raid alert was lifted. To conserve fuel and aircraft, the Japanese had decided not to intercept small formations. The normal radio broadcast warning was given to the people that it might be advisable to go to air-raid shelters if B-29s were actually sighted, but no raid was expected beyond some sort of reconnaissance.
Seizo Yamada's ground level photo taken from approximately 7 km northeast of Hiroshima.
Hiroshima was the primary target of the first nuclear bombing mission on August 6, with Kokura and Nagasaki being alternative targets. August 6 was chosen because there had previously been cloud cover over the target. The 393d Bombardment Squadron B-29 Enola Gay, piloted and commanded by 509th Composite Group commander Colonel Paul Tibbets, was launched from North Field airbase on Tinian in the West Pacific, about six hours flight time from Japan. The Enola Gay (named after Colonel Tibbets' mother) was accompanied by two other B29s, The Great Artiste which carried instrumentation, commanded by Major Charles W. Sweeney, and a then-nameless aircraft later called Necessary Evil (the photography aircraft) commanded by Captain George Marquardt.[18]
After leaving Tinian the aircraft made their way separately to Iwo Jima where they rendezvoused at 2,440 m (8,000 ft) and set course for Japan. The aircraft arrived over the target in clear visibility at 9,855 m (32,000 ft). On the journey, Navy Captain William Parsons had armed the bomb, which had been left unarmed to minimize the risks during takeoff. His assistant, 2nd Lt. Morris Jeppson, removed the safety devices thirty minutes before reaching the target area.[19]
Hiroshima, in the aftermath of the bombing
The release at 08:15 (Hiroshima time) was uneventful, and the gravity bomb known as "Little Boy", a gun-type fission weapon with 60 kg (130 pounds) of uranium-235, took fifty-seven seconds to fall from the aircraft to the predetermined detonation height about six hundred meters (1,900 ft) above the city. Due to crosswind, it missed the aiming point, the Aioi Bridge, by almost eight hundred feet and detonated directly over Shima Surgical Clinic.[20] It created a blast equivalent to about 13 kilotons of TNT. (The U-235 weapon was considered very inefficient, with only 1.38% of its material fissioning.)[21] The radius of total destruction was about one mile (1.6 km), with resulting fires across 11.4 km² (4.4 square miles).[22] Infrastructure damage was estimated at ninety percent of Hiroshima's buildings being either damaged or completely destroyed.
About an hour before the bombing, Japanese early warning radar detected the approach of some American aircraft headed for the southern part of Japan. An alert was given and radio broadcasting stopped in many cities, among them Hiroshima. At nearly 08:00, the radar operator in Hiroshima determined that the number of planes coming in was very small—probably not more than three—and the air raid alert was lifted. To conserve fuel and aircraft, the Japanese had decided not to intercept small formations. The normal radio broadcast warning was given to the people that it might be advisable to go to air-raid shelters if B-29s were actually sighted, but no raid was expected beyond some sort of reconnaissance.
Hiroshima during World War II
At the time of its bombing, Hiroshima was a city of some industrial and military significance. A number of military camps were located nearby, including the headquarters of the Fifth Division and Field Marshal Shunroku Hata's 2nd General Army Headquarters, which commanded the defense of all of southern Japan. Hiroshima was a minor supply and logistics base for the Japanese military. The city was a communications center, a storage point, and an assembly area for troops. It was one of several Japanese cities left deliberately untouched by American bombing, allowing a pristine environment to measure the damage caused by the atomic bomb.
A postwar "Little Boy" casing mockup
The center of the city contained several reinforced concrete buildings and lighter structures. Outside the center, the area was congested by a dense collection of small wooden workshops set among Japanese houses. A few larger industrial plants lay near the outskirts of the city. The houses were of wooden construction with tile roofs, and many of the industrial buildings also were of wood frame construction. The city as a whole was highly susceptible to fire damage.
The population of Hiroshima had reached a peak of over 381,000 earlier in the war, but prior to the atomic bombing the population had steadily decreased because of a systematic evacuation ordered by the Japanese government. At the time of the attack the population was approximately 255,000. This figure is based on the registered population used by the Japanese in computing ration quantities, and the estimates of additional workers and troops who were brought into the city may be inaccurate.
A postwar "Little Boy" casing mockup
The center of the city contained several reinforced concrete buildings and lighter structures. Outside the center, the area was congested by a dense collection of small wooden workshops set among Japanese houses. A few larger industrial plants lay near the outskirts of the city. The houses were of wooden construction with tile roofs, and many of the industrial buildings also were of wood frame construction. The city as a whole was highly susceptible to fire damage.
The population of Hiroshima had reached a peak of over 381,000 earlier in the war, but prior to the atomic bombing the population had steadily decreased because of a systematic evacuation ordered by the Japanese government. At the time of the attack the population was approximately 255,000. This figure is based on the registered population used by the Japanese in computing ration quantities, and the estimates of additional workers and troops who were brought into the city may be inaccurate.
The Manhattan Project
Main article: Manhattan Project
The United States, with assistance from the United Kingdom and Canada in their respective secret projects Tube Alloys and Chalk River Laboratories,[9] designed and built the first atomic bombs under what was called the Manhattan Project. The scientific research was directed by American physicist J. Robert Oppenheimer. The Hiroshima bomb, a gun-type bomb called "Little Boy", was made with uranium-235, a rare isotope of uranium. The atomic bomb was first tested at Trinity Site, on July 16, 1945, near Alamogordo, New Mexico. The test weapon, "the gadget," and the Nagasaki bomb, "Fat Man", were both implosion-type devices made primarily of plutonium-239, a synthetic element.[10]
Choice of targets
Map showing the locations of Hiroshima and Nagasaki, Japan where the two atomic weapons were employed
On May 10–11, 1945 The Target Committee at Los Alamos, led by J. Robert Oppenheimer, recommended Kyoto, Hiroshima, Yokohama, and the arsenal at Kokura as possible targets. The target selection was subject to the following criteria:
They are larger than three miles in diameter and are important targets in a large urban area.
The blast would create effective damage.
They are unlikely to be attacked by August 1945. "Any small and strictly military objective should be located in a much larger area subject to blast damage in order to avoid undue risks of the weapon being lost due to bad placing of the bomb."
These cities were largely untouched during the nightly bombing raids and the Army Air Force agreed to leave them off the target list so accurate assessment of the weapon could be made. Hiroshima was described as "an important army depot and port of embarkation in the middle of an urban industrial area. It is a good radar target and it is such a size that a large part of the city could be extensively damaged. There are adjacent hills which are likely to produce a focussing effect which would considerably increase the blast damage. Due to rivers it is not a good incendiary target." The goal of the weapon was to convince Japan to surrender unconditionally in accordance with the terms of the Potsdam Declaration. The Target Committee stated that "It was agreed that psychological factors in the target selection were of great importance. Two aspects of this are (1) obtaining the greatest psychological effect against Japan and (2) making the initial use sufficiently spectacular for the importance of the weapon to be internationally recognized when publicity on it is released. In this respect Kyoto has the advantage of the people being more highly intelligent and hence better able to appreciate the significance of the weapon. Hiroshima has the advantage of being such a size and with possible focussing from nearby mountains that a large fraction of the city may be destroyed. The Emperor's palace in Tokyo has a greater fame than any other target but is of least strategic value."[11]
During World War II, Edwin O. Reischauer was the Japan expert for the US Army Intelligence Service, in which role he is incorrectly said to have prevented the bombing of Kyoto.[12] In his autobiography, Reischauer specifically refuted the validity of this broadly-accepted claim:
"...the only person deserving credit for saving Kyoto from destruction is Henry L. Stimson, the Secretary of War at the time, who had known and admired Kyoto ever since his honeymoon there several decades earlier."[13]
The Potsdam ultimatum
On July 26, Truman and other allied leaders issued The Potsdam Declaration outlining terms of surrender for Japan. It was presented as an ultimatum and stated that without a surrender, the Allies would attack Japan, resulting in "the inevitable and complete destruction of the Japanese armed forces and just as inevitably the utter devastation of the Japanese homeland" but the atomic bomb was not mentioned. On July 28, Japanese papers reported that the declaration had been rejected by the Japanese government. That afternoon, Prime Minister Kantaro Suzuki declared at a press conference that the Potsdam Declaration was no more than a rehash (yakinaoshi) of the Cairo Declaration and that the government intended to ignore it (mokusatsu lit. "kill by silence").[14] The statement was taken by both Japanese and foreign papers as a clear rejection of the declaration. Emperor Hirohito, who was waiting for a Soviet reply to noncommittal Japanese peace feelers made no move to change the government position.[15] On July 31, he made clear to his advisor Kōichi Kido that the Imperial Regalia of Japan had to be defended at all costs.[16]
In early July, on his way to Potsdam, Truman had re-examined the decision to use the bomb. In the end, Truman made the decision to drop the atomic bombs on Japan. His stated intention in ordering the bombings was to bring about a quick resolution of the war by inflicting destruction and instilling fear of further destruction in sufficient strength to cause Japan to surrender.[17
The United States, with assistance from the United Kingdom and Canada in their respective secret projects Tube Alloys and Chalk River Laboratories,[9] designed and built the first atomic bombs under what was called the Manhattan Project. The scientific research was directed by American physicist J. Robert Oppenheimer. The Hiroshima bomb, a gun-type bomb called "Little Boy", was made with uranium-235, a rare isotope of uranium. The atomic bomb was first tested at Trinity Site, on July 16, 1945, near Alamogordo, New Mexico. The test weapon, "the gadget," and the Nagasaki bomb, "Fat Man", were both implosion-type devices made primarily of plutonium-239, a synthetic element.[10]
Choice of targets
Map showing the locations of Hiroshima and Nagasaki, Japan where the two atomic weapons were employed
On May 10–11, 1945 The Target Committee at Los Alamos, led by J. Robert Oppenheimer, recommended Kyoto, Hiroshima, Yokohama, and the arsenal at Kokura as possible targets. The target selection was subject to the following criteria:
They are larger than three miles in diameter and are important targets in a large urban area.
The blast would create effective damage.
They are unlikely to be attacked by August 1945. "Any small and strictly military objective should be located in a much larger area subject to blast damage in order to avoid undue risks of the weapon being lost due to bad placing of the bomb."
These cities were largely untouched during the nightly bombing raids and the Army Air Force agreed to leave them off the target list so accurate assessment of the weapon could be made. Hiroshima was described as "an important army depot and port of embarkation in the middle of an urban industrial area. It is a good radar target and it is such a size that a large part of the city could be extensively damaged. There are adjacent hills which are likely to produce a focussing effect which would considerably increase the blast damage. Due to rivers it is not a good incendiary target." The goal of the weapon was to convince Japan to surrender unconditionally in accordance with the terms of the Potsdam Declaration. The Target Committee stated that "It was agreed that psychological factors in the target selection were of great importance. Two aspects of this are (1) obtaining the greatest psychological effect against Japan and (2) making the initial use sufficiently spectacular for the importance of the weapon to be internationally recognized when publicity on it is released. In this respect Kyoto has the advantage of the people being more highly intelligent and hence better able to appreciate the significance of the weapon. Hiroshima has the advantage of being such a size and with possible focussing from nearby mountains that a large fraction of the city may be destroyed. The Emperor's palace in Tokyo has a greater fame than any other target but is of least strategic value."[11]
During World War II, Edwin O. Reischauer was the Japan expert for the US Army Intelligence Service, in which role he is incorrectly said to have prevented the bombing of Kyoto.[12] In his autobiography, Reischauer specifically refuted the validity of this broadly-accepted claim:
"...the only person deserving credit for saving Kyoto from destruction is Henry L. Stimson, the Secretary of War at the time, who had known and admired Kyoto ever since his honeymoon there several decades earlier."[13]
The Potsdam ultimatum
On July 26, Truman and other allied leaders issued The Potsdam Declaration outlining terms of surrender for Japan. It was presented as an ultimatum and stated that without a surrender, the Allies would attack Japan, resulting in "the inevitable and complete destruction of the Japanese armed forces and just as inevitably the utter devastation of the Japanese homeland" but the atomic bomb was not mentioned. On July 28, Japanese papers reported that the declaration had been rejected by the Japanese government. That afternoon, Prime Minister Kantaro Suzuki declared at a press conference that the Potsdam Declaration was no more than a rehash (yakinaoshi) of the Cairo Declaration and that the government intended to ignore it (mokusatsu lit. "kill by silence").[14] The statement was taken by both Japanese and foreign papers as a clear rejection of the declaration. Emperor Hirohito, who was waiting for a Soviet reply to noncommittal Japanese peace feelers made no move to change the government position.[15] On July 31, he made clear to his advisor Kōichi Kido that the Imperial Regalia of Japan had to be defended at all costs.[16]
In early July, on his way to Potsdam, Truman had re-examined the decision to use the bomb. In the end, Truman made the decision to drop the atomic bombs on Japan. His stated intention in ordering the bombings was to bring about a quick resolution of the war by inflicting destruction and instilling fear of further destruction in sufficient strength to cause Japan to surrender.[17
Atomic bombings of Hiroshima and Nagasaki
The atomic bombings of Hiroshima and Nagasaki were nuclear attacks near the end of World War II against the Empire of Japan by the United States at the executive order of U.S. President Harry S. Truman on August 6 and 9, 1945. After six months of intense fire-bombing of 67 other Japanese cities, the nuclear weapon "Little Boy" was dropped on the city of Hiroshima on Monday,[1] August 6, 1945, [2] followed on August 9 by the detonation of the "Fat Man" nuclear bomb over Nagasaki. These are to date the only attacks with nuclear weapons in the history of warfare.[3]
The bombs killed as many as 140,000 people in Hiroshima and 80,000 in Nagasaki by the end of 1945,[4] roughly half on the days of the bombings. Since then, thousands more have died from injuries or illness attributed to exposure to radiation released by the bombs.[1] In both cities, the overwhelming majority of the dead were civilians.[5][6][7]
Six days after the detonation over Nagasaki, on August 15, Japan announced its surrender to the Allied Powers, signing the Instrument of Surrender on September 2, officially ending the Pacific War and therefore World War II. (Germany had signed its unavoidable[2] Instrument of Surrender on May 7, ending the war in Europe.) The bombings led, in part, to post-war Japan adopting Three Non-Nuclear Principles, forbidding that nation from nuclear armament.[8]
The bombs killed as many as 140,000 people in Hiroshima and 80,000 in Nagasaki by the end of 1945,[4] roughly half on the days of the bombings. Since then, thousands more have died from injuries or illness attributed to exposure to radiation released by the bombs.[1] In both cities, the overwhelming majority of the dead were civilians.[5][6][7]
Six days after the detonation over Nagasaki, on August 15, Japan announced its surrender to the Allied Powers, signing the Instrument of Surrender on September 2, officially ending the Pacific War and therefore World War II. (Germany had signed its unavoidable[2] Instrument of Surrender on May 7, ending the war in Europe.) The bombings led, in part, to post-war Japan adopting Three Non-Nuclear Principles, forbidding that nation from nuclear armament.[8]
Monday, February 23, 2009
Military of Pakistan
The Pakistan Armed Forces (Urdu: پاک عسکری, Pāk Askarī) are the overall unified military forces of Pakistan. The Pakistani military was first formed when the nation achieved independence from the British Empire during the partition of India in 1947.
Its component branches are:
Pakistan Army
Pakistan Navy
Pakistan Air Force
Paramilitary forces of Pakistan
Pakistan Coast Guard
Pakistan Strategic Nuclear Command
The Army, Navy and Air Force were commissioned in 1947 in anticipation of a potential hostilities against India. From the time of its inception, the military played a decisive role in the History of Pakistan. A sense of national unity and identity was forged out of the wars of 1947 and 1965 against India.
Approximately 650,000 personnel are on active duty in the military which is the world's 7th largest armed force as of 2008.[2] Combined with the 302,000 strong Paramilitary forces and 520,000 in reserve, the Military of Pakistan has a total size of nearly 1,400,000 personnel. The Military draws its manpower from a large pool of volunteers and as such, conscription is not, and has never been needed.[citation needed]
Pakistan's military is led by an officer corps that is not restricted by social class or nobility and are appointed from a variety of sources such as service academies and direct appointment from both civilian status and the enlisted ranks. The armed forces are highly respected in civil society and the social ranks as an institution[citation needed]. September 6 known as Defence Day commemorates the military's role in defense of the nation.
The Pakistani armed forces are the largest contributors to United Nations peacekeeping efforts, with more than 10,000 personnel deployed in 2007.[3] Other foreign deployments have consisted of Pakistani military personnel as advisers in African and Arab countries. The Pakistani military maintained Division and brigade strength presences in some of the Arab countries during the past Arab-Israeli Wars, and the first Gulf War to help the Coalition, in Somalian & Kosovo conflicts.
Its component branches are:
Pakistan Army
Pakistan Navy
Pakistan Air Force
Paramilitary forces of Pakistan
Pakistan Coast Guard
Pakistan Strategic Nuclear Command
The Army, Navy and Air Force were commissioned in 1947 in anticipation of a potential hostilities against India. From the time of its inception, the military played a decisive role in the History of Pakistan. A sense of national unity and identity was forged out of the wars of 1947 and 1965 against India.
Approximately 650,000 personnel are on active duty in the military which is the world's 7th largest armed force as of 2008.[2] Combined with the 302,000 strong Paramilitary forces and 520,000 in reserve, the Military of Pakistan has a total size of nearly 1,400,000 personnel. The Military draws its manpower from a large pool of volunteers and as such, conscription is not, and has never been needed.[citation needed]
Pakistan's military is led by an officer corps that is not restricted by social class or nobility and are appointed from a variety of sources such as service academies and direct appointment from both civilian status and the enlisted ranks. The armed forces are highly respected in civil society and the social ranks as an institution[citation needed]. September 6 known as Defence Day commemorates the military's role in defense of the nation.
The Pakistani armed forces are the largest contributors to United Nations peacekeeping efforts, with more than 10,000 personnel deployed in 2007.[3] Other foreign deployments have consisted of Pakistani military personnel as advisers in African and Arab countries. The Pakistani military maintained Division and brigade strength presences in some of the Arab countries during the past Arab-Israeli Wars, and the first Gulf War to help the Coalition, in Somalian & Kosovo conflicts.
Notes
ttp://www.fas.org/nuke/guide/pakistan/nuke/index.html. Retrieved on 2007-02-22.
^ "Uranium Institute News Briefing 00.25 14 - 22 June 2000". Uranium Institute. 2000. http://www.world-nuclear.org/nb/nb00/nb0025.htm. Retrieved on 2006-05-07.
^ Key Issues: Nuclear Energy: Issues: IAEA: World Plutonium Inventories
^ BBC NEWS World South Asia Pakistan nuclear report disputed
^ Pakistan Expanding Nuclear Program - washingtonpost.com
^ BBC NEWS World South Asia Pakistan 'building new reactor'
^ U.S. Group Says Pakistan Is Building New Reactor - New York Times
^ Federation of American Scientists
^ Center for Defense Information
^ "US Navy Strategic Insights. Feb 2003". US Navy. 2003. http://www.ccc.nps.navy.mil/si/feb03/southAsia2.asp. Retrieved on 2006-10-28.
^ Pakistan's Nuclear Arsenal Underestimated, Reports Say
^ Impact of US wargames on Pakistan N-arms ‘negative’ -DAWN - Top Stories; December 03, 2007
^ Calculating the Risks in Pakistan - washingtonpost.com
^ China tested N-weapons for Pak: US insider The Times of India September 6, 2008
^ http://www.csis-scrs.gc.ca/pblctns/prspctvs/200110-eng.asp
^ "U.S. Secretly Aids Pakistan in Guarding Nuclear Arms". The New York Times. 2007-11-18. http://www.nytimes.com/2007/11/18/washington/18nuke.html?ref=us. Retrieved on 2007-11-18.
^ New York Times/18 November 2007
^ "Uranium Institute News Briefing 00.25 14 - 22 June 2000". Uranium Institute. 2000. http://www.world-nuclear.org/nb/nb00/nb0025.htm. Retrieved on 2006-05-07.
^ Key Issues: Nuclear Energy: Issues: IAEA: World Plutonium Inventories
^ BBC NEWS World South Asia Pakistan nuclear report disputed
^ Pakistan Expanding Nuclear Program - washingtonpost.com
^ BBC NEWS World South Asia Pakistan 'building new reactor'
^ U.S. Group Says Pakistan Is Building New Reactor - New York Times
^ Federation of American Scientists
^ Center for Defense Information
^ "US Navy Strategic Insights. Feb 2003". US Navy. 2003. http://www.ccc.nps.navy.mil/si/feb03/southAsia2.asp. Retrieved on 2006-10-28.
^ Pakistan's Nuclear Arsenal Underestimated, Reports Say
^ Impact of US wargames on Pakistan N-arms ‘negative’ -DAWN - Top Stories; December 03, 2007
^ Calculating the Risks in Pakistan - washingtonpost.com
^ China tested N-weapons for Pak: US insider The Times of India September 6, 2008
^ http://www.csis-scrs.gc.ca/pblctns/prspctvs/200110-eng.asp
^ "U.S. Secretly Aids Pakistan in Guarding Nuclear Arms". The New York Times. 2007-11-18. http://www.nytimes.com/2007/11/18/washington/18nuke.html?ref=us. Retrieved on 2007-11-18.
^ New York Times/18 November 2007
Naval Delivery
Naval Delivery: PNS Hamza has just been commissioned this year in August, This submarine is an Augosta 90B and, with a number of modifications, will be able to fire ballistic missiles. These modifications may be happening soon. It can also fire Babur Cruise Missiles and that is if the submarine uses larger tubes to fire this missile. Soon, other ships and submarines maybe retrofitted to fire ballistic and cruise missiles.
[edit] Aircraft delivery
There are two units operating the Chinese-built A-5 (No. 16 Sqn and No. 26 Sqn), an aircraft believed to be a leading candidate for the aerial delivery of Pakistan's nuclear weapons. The others are the Mirage IIIOs, Mirage IIIODs and Mirage IIIEs. The Pakistani Air Force, currently, operates some 156 Mirage (III & V) aircraft. The allocation of 90 of these aircraft is not, currently, known. Pakistan also has 74 F-16 Fighter aircraft—all block 15s. As of now, it recently received 2 block 15OCUs through Peace Gate 3/4 as a good-will gesture from the US Government in November 2006. All of these F-16s are capable of delivering nuclear warheads, they are split into 2 squadrons, both stationed at PAF Sargodha. It is rumoured that the 34 current PAF F-16s have been modified for nuclear weapons delivery by PAC, Kamra. Also, in the 1990s, the PAF F-16s have practised toss-bombing which is a method to deliver nuclear weapons. Pakistan prefers to use ballistic missiles and cruise missiles to deliver nuclear warheads because they have a much longer range than aircraft and do not need the airspace to be cleared of aircraft and SAMS.
In an attempt to modernize its Air Force, Pakistan has recently signed a deal for the purchase of 26 F-16 block 15OCUs that were under Peace Gate 3/4 and 60 MLU [2] kits for block 15s, AMRAAMs, LGBs, and various other missiles and bombs and other items, the purchase of 18 F-16 block 50/52+ [3] with an option of 18 more. If all options are exercised, this deal will cost US$5 billion. All of these F-16s will be capable of nuclear weapons delivery.
Also, by early 2007, the first 8 JF-17 Thunder aircraft [4] (FC-1s) will enter the PAF service. These are pre-production aircraft and more JF-17 Thunder aircraft will follow. These, too, will be capable of nuclear weapons delivery. Pakistan has also ordered 36 Chinese J-10s [5] for its airforce for a cost of $1.4 billion. Pakistan Air Force's desire to modernize its fleet is hampered by Pakistan's precarious economic condition.[6]
Pakistan has also recently tested its Babur cruise missile having a range of 500 km. Its design clearly appears to be influenced by the Tomahawk cruise missile of the US in terms of appearance and specifications. However Pakistan steadfastly stands by its claims of an indigenous design of the Babur. It is a ground-launched version and, according to the Pakistan Military sources, the submarine- and air-delivered versions are soon to follow.
In an attempt to modernize its Air Force, Pakistan has recently signed a deal for the purchase of 26 F-16 block 15OCUs that were under Peace Gate 3/4 and 60 MLU [2] kits for block 15s, AMRAAMs, LGBs, and various other missiles and bombs and other items, the purchase of 18 F-16 block 50/52+ [3] with an option of 18 more. If all options are exercised, this deal will cost US$5 billion. All of these F-16s will be capable of nuclear weapons delivery.
Also, by early 2007, the first 8 JF-17 Thunder aircraft [4] (FC-1s) will enter the PAF service. These are pre-production aircraft and more JF-17 Thunder aircraft will follow. These, too, will be capable of nuclear weapons delivery. Pakistan has also ordered 36 Chinese J-10s [5] for its airforce for a cost of $1.4 billion. Pakistan Air Force's desire to modernize its fleet is hampered by Pakistan's precarious economic condition.[6]
Pakistan has also recently tested its Babur cruise missile having a range of 500 km. Its design clearly appears to be influenced by the Tomahawk cruise missile of the US in terms of appearance and specifications. However Pakistan steadfastly stands by its claims of an indigenous design of the Babur. It is a ground-launched version and, according to the Pakistan Military sources, the submarine- and air-delivered versions are soon to follow.
Missiles
Below is the list of all the missiles currently in Pakistan's inventory or under development that can carry a non-conventional payload (Nuclear in Pakistan's case).
Pakistan's Nuclear Capable Missiles
Name/Designation
Class
Range: Max Range with Min Payload
Payload
Status
Hatf-I
SRBM
100 Km
500 Kg
Operational with Pakistan's Armed Forces
Abdali
SRBM
180 Km
500 Kg
Operational with Pakistan's Armed Forces
Ghaznavi
SRBM
290 Km
500 Kg
Operational with Pakistan's Armed Forces
M-11
SRBM
300 Km
500 Kg
Operational with Pakistan's Armed Forces
Shaheen-I
SRBM
750 Km
850 Kg
Operational with Pakistan's Armed Forces
Ghauri-I
MRBM
1500 Km
750 Kg
Operational with Pakistan's Armed Forces
Ghauri-II
MRBM
1800-2300 Km
750-1200 Kg
Operational with Pakistan's Armed Forces
Shaheen-II
MRBM
2000-3500 Km
500-2500 Kg
Operational with Pakistan's Armed Forces
Ghauri-III
IRBM
3600+ Km
1200+ Kg
Under Development
Shaheen-III
IRBM
4000+ Km
1200+ Kg
Under Development
Babur
Land Attack Cruise missile
700 Km
500 Kg
Operational with Pakistan's Armed Forces
Ra'ad
Air Launched Cruise Missile
350 Km
500 Kg
Operational with Pakistan's Armed Forces
Pakistan's Nuclear Capable Missiles
Name/Designation
Class
Range: Max Range with Min Payload
Payload
Status
Hatf-I
SRBM
100 Km
500 Kg
Operational with Pakistan's Armed Forces
Abdali
SRBM
180 Km
500 Kg
Operational with Pakistan's Armed Forces
Ghaznavi
SRBM
290 Km
500 Kg
Operational with Pakistan's Armed Forces
M-11
SRBM
300 Km
500 Kg
Operational with Pakistan's Armed Forces
Shaheen-I
SRBM
750 Km
850 Kg
Operational with Pakistan's Armed Forces
Ghauri-I
MRBM
1500 Km
750 Kg
Operational with Pakistan's Armed Forces
Ghauri-II
MRBM
1800-2300 Km
750-1200 Kg
Operational with Pakistan's Armed Forces
Shaheen-II
MRBM
2000-3500 Km
500-2500 Kg
Operational with Pakistan's Armed Forces
Ghauri-III
IRBM
3600+ Km
1200+ Kg
Under Development
Shaheen-III
IRBM
4000+ Km
1200+ Kg
Under Development
Babur
Land Attack Cruise missile
700 Km
500 Kg
Operational with Pakistan's Armed Forces
Ra'ad
Air Launched Cruise Missile
350 Km
500 Kg
Operational with Pakistan's Armed Forces
Nuclear weapon design
Nuclear weapon designs are physical, chemical, and engineering arrangements that cause the physics package[1] of a nuclear weapon to detonate. There are three basic design types. In all three, the explosive energy is derived primarily from nuclear fission, not fusion.
Pure fission weapons were the first nuclear weapons built and have so far been the only type ever used in warfare. The active material is fissile uranium (U-235) or plutonium (Pu-239), explosively assembled into a chain-reacting critical mass by one of two methods:
Gun assembly, in which one piece of fissile uranium is fired at a fissile uranium target at the end of the weapon, similar to firing a bullet down a gun barrel (plutonium can be used in this design, but it has proven to be impractical), or
Implosion, in which a fissile mass of either material (U-235, Pu-239, or a combination) is surrounded by high explosives that compress the mass, resulting in criticality.
Fusion-boosted fission weapons improve on the implosion design. The high temperature and pressure environment at the center of an exploding fission weapon compresses and heats a mixture of tritium and deuterium gas (heavy isotopes of hydrogen). The hydrogen fuses to form helium and free neutrons. The energy release from fusion reactions is relatively negligible, but each neutron starts a new fission chain reaction, greatly reducing the amount of fissile material that would otherwise be wasted. Boosting can more than double the weapon's fission energy release.
Two-stage thermonuclear weapons are essentially a daisy chain of fusion-boosted fission weapons, with only two daisies, or stages, in the chain. The second stage, called the "secondary," is imploded by x-ray energy from the first stage, called the "primary." This radiation implosion is much more effective than the high-explosive implosion of the primary. Consequently, the secondary can be many times more powerful than the primary, without being bigger. The secondary could be designed to maximize fusion energy release, but in most designs fusion is employed only to drive or enhance fission, as it is in the primary. More stages could be added, but the result would be a multi-megaton weapon too powerful to be useful. (The United States briefly deployed a three-stage 25-megaton bomb, the B41, starting in 1961. Also in 1961, the Soviet Union tested, but did not deploy, a three-stage 50-megaton device, Tsar Bomba.)
Pure fission weapons historically have been the first type to be built by a nation state. Large industrial states with well-developed nuclear arsenals have two-stage thermonuclear weapons, which are the most compact, scalable, and cost effective option once the necessary industrial infrastructure is built.
All innovations in nuclear weapon design originated in the United States, although some were later developed independently by other states;[2] the following descriptions feature U.S. designs.
In early news accounts, pure fission weapons were called atomic bombs or A-bombs, a misnomer since the energy comes only from the nucleus of the atom. Weapons involving fusion were called hydrogen bombs or H-bombs, also a misnomer since their destructive energy comes mostly from fission. Insiders favored the terms nuclear and thermonuclear, respectively.
The term thermonuclear refers to the high temperatures required to initiate fusion. It ignores the equally important factor of pressure, which was considered secret at the time the term became current. Many nuclear weapon terms are similarly inaccurate because of their origin in a classified environment. Some are nonsense code words such as "alarm clock" (see below).
Pure fission weapons were the first nuclear weapons built and have so far been the only type ever used in warfare. The active material is fissile uranium (U-235) or plutonium (Pu-239), explosively assembled into a chain-reacting critical mass by one of two methods:
Gun assembly, in which one piece of fissile uranium is fired at a fissile uranium target at the end of the weapon, similar to firing a bullet down a gun barrel (plutonium can be used in this design, but it has proven to be impractical), or
Implosion, in which a fissile mass of either material (U-235, Pu-239, or a combination) is surrounded by high explosives that compress the mass, resulting in criticality.
Fusion-boosted fission weapons improve on the implosion design. The high temperature and pressure environment at the center of an exploding fission weapon compresses and heats a mixture of tritium and deuterium gas (heavy isotopes of hydrogen). The hydrogen fuses to form helium and free neutrons. The energy release from fusion reactions is relatively negligible, but each neutron starts a new fission chain reaction, greatly reducing the amount of fissile material that would otherwise be wasted. Boosting can more than double the weapon's fission energy release.
Two-stage thermonuclear weapons are essentially a daisy chain of fusion-boosted fission weapons, with only two daisies, or stages, in the chain. The second stage, called the "secondary," is imploded by x-ray energy from the first stage, called the "primary." This radiation implosion is much more effective than the high-explosive implosion of the primary. Consequently, the secondary can be many times more powerful than the primary, without being bigger. The secondary could be designed to maximize fusion energy release, but in most designs fusion is employed only to drive or enhance fission, as it is in the primary. More stages could be added, but the result would be a multi-megaton weapon too powerful to be useful. (The United States briefly deployed a three-stage 25-megaton bomb, the B41, starting in 1961. Also in 1961, the Soviet Union tested, but did not deploy, a three-stage 50-megaton device, Tsar Bomba.)
Pure fission weapons historically have been the first type to be built by a nation state. Large industrial states with well-developed nuclear arsenals have two-stage thermonuclear weapons, which are the most compact, scalable, and cost effective option once the necessary industrial infrastructure is built.
All innovations in nuclear weapon design originated in the United States, although some were later developed independently by other states;[2] the following descriptions feature U.S. designs.
In early news accounts, pure fission weapons were called atomic bombs or A-bombs, a misnomer since the energy comes only from the nucleus of the atom. Weapons involving fusion were called hydrogen bombs or H-bombs, also a misnomer since their destructive energy comes mostly from fission. Insiders favored the terms nuclear and thermonuclear, respectively.
The term thermonuclear refers to the high temperatures required to initiate fusion. It ignores the equally important factor of pressure, which was considered secret at the time the term became current. Many nuclear weapon terms are similarly inaccurate because of their origin in a classified environment. Some are nonsense code words such as "alarm clock" (see below).
Weapons delivery
Main article: Nuclear weapons delivery
The first nuclear weapons were gravity bombs, such as the "Fat Man" weapon dropped on Nagasaki, Japan. These weapons were very large and could only be delivered by a bomber aircraft
Nuclear weapons delivery—the technology and systems used to bring a nuclear weapon to its target—is an important aspect of nuclear weapons relating both to nuclear weapon design and nuclear strategy. Additionally, developing and maintaining delivery options is among the most resource-intensive aspects of nuclear weapons: according to one estimate, deployment of nuclear weapons accounted for 57% of the total financial resources spent by the United States in relation to nuclear weapons since 1940.[6]
Historically the first method of delivery, and the method used in the two nuclear weapons actually used in warfare, is as a gravity bomb, dropped from bomber aircraft. This method is usually the first developed by countries as it does not place many restrictions on the size of the weapon, and weapon miniaturization is something which requires considerable weapons design knowledge. It does, however, limit the range of attack, the response time to an impending attack, and the number of weapons which can be fielded at any given time. Additionally, specialized delivery systems are usually not necessary; especially with the advent of miniaturization, nuclear bombs can be delivered by both strategic bombers and tactical fighter-bombers, allowing an air force to use its current fleet with little or no modification. This method may still be considered the primary means of nuclear weapons delivery; the majority of U.S. nuclear warheads, for example, are represented in free-fall gravity bombs, namely the B61.[2]
More preferable from a strategic point of view are nuclear weapons mounted onto a missile, which can use a ballistic trajectory to deliver a warhead over the horizon. While even short range missiles allow for a faster and less vulnerable attack, the development of intercontinental ballistic missiles (ICBMs) and submarine-launched ballistic missiles (SLBMs) has allowed some nations to plausibly deliver missiles anywhere on the globe with a high likelihood of success. More advanced systems, such as multiple independently targetable reentry vehicles (MIRVs) allow multiple warheads to be launched at several targets from any one missile, reducing the chance of any successful missile defense. Today, missiles are most common among systems designed for delivery of nuclear weapons. Making a warhead small enough to fit onto a missile, though, can be a difficult task.[2]
Tactical weapons (see above) have involved the most variety of delivery types, including not only gravity bombs and missiles but also artillery shells, land mines, and nuclear depth charges and torpedoes for anti-submarine warfare. An atomic mortar was also tested at one time by the United States. Small, two-man portable tactical weapons (somewhat misleadingly referred to as suitcase bombs), such as the Special Atomic Demolition Munition, have been developed, although the difficulty to combine sufficient yield with portability limits their military utility.[2]
Types of nuclear weapons Of Pakistan
Main article: Nuclear weapon design
The two basic fission weapon designs
There are two basic types of nuclear weapon. The first type produces its explosive energy through nuclear fission reactions alone. Such fission weapons also commonly referred to as atomic bombs or atom bombs (abbreviated as A-bombs), though their energy comes specifically from the nucleus of the atom.
In fission weapons, a mass of fissile material (enriched uranium or plutonium) is assembled into a supercritical mass—the amount of material needed to start an exponentially growing nuclear chain reaction—either by shooting one piece of sub-critical material into another (the "gun" method), or by compressing a sub-critical sphere of material using chemical explosives to many times its original density (the "implosion" method). The latter approach is considered more sophisticated than the former, and only the latter approach can be used if plutonium is the fissile material.
A major challenge in all nuclear weapon designs is to ensure that a significant fraction of the fuel is consumed before the weapon destroys itself. The amount of energy released by fission bombs can range between the equivalent of less than a ton of TNT upwards to around 500,000 tons (500 kilotons) of TNT.[2]
The second basic type of nuclear weapon produces a large amount of its energy through nuclear fusion reactions. Such fusion weapons are generally referred to as thermonuclear weapons or more colloquially as hydrogen bombs (abbreviated as H-bombs), as they rely on fusion reactions between isotopes of hydrogen (deuterium and tritium). However, all such weapons derive a significant portion – and sometimes a majority – of their energy from fission (including fission induced by neutrons from fusion reactions). Unlike fission weapons, there are no inherent limits on the energy released by thermonuclear weapons. Only six countries—United States, Russia, United Kingdom, People's Republic of China, France and India—have conducted thermonuclear weapon tests. (Whether India has detonated a "true," multi-staged thermonuclear weapon is controversial.)[3]
The basics of the Teller–Ulam design for a hydrogen bomb: a fission bomb uses radiation to compress and heat a separate section of fusion fuel.
Thermonuclear bombs work by using the energy of a fission bomb in order to compress and heat fusion fuel. In the Teller-Ulam design, which accounts for all multi-megaton yield hydrogen bombs, this is accomplished by placing a fission bomb and fusion fuel (tritium, deuterium, or lithium deuteride) in proximity within a special, radiation-reflecting container. When the fission bomb is detonated, gamma and X-rays emitted first compress the fusion fuel, then heat it to thermonuclear temperatures. The ensuing fusion reaction creates enormous numbers of high-speed neutrons, which then can induce fission in materials which normally are not prone to it, such as depleted uranium. Each of these components is known as a "stage," with the fission bomb as the "primary" and the fusion capsule as the "secondary." In large hydrogen bombs, about half of the yield, and much of the resulting nuclear fallout, comes from the final fissioning of depleted uranium.[2] By chaining together numerous stages with increasing amounts of fusion fuel, thermonuclear weapons can be made to an almost arbitrary yield; the largest ever detonated (the Tsar Bomba of the USSR) released an energy equivalent to over 50 million tons (50 megatons) of TNT. Most thermonuclear weapons are considerably smaller than this, due for instance to practical constraints in fitting them into the space and weight requirements of missile warheads.[4]
There are other types of nuclear weapons as well. For example, a boosted fission weapon is a fission bomb which increases its explosive yield through a small amount of fusion reactions, but it is not a fusion bomb. In the boosted bomb, the neutrons produced by the fusion reactions serve primarily to increase the efficiency of the fission bomb. Some weapons are designed for special purposes; a neutron bomb is a thermonuclear weapon that yields a relatively small explosion but a relatively large amount of neutron radiation; such a device could theoretically be used to cause massive casualties while leaving infrastructure mostly intact and creating a minimal amount of fallout. The detonation of a nuclear weapon is accompanied by a blast of neutron radiation. Surrounding a nuclear weapon with suitable materials (such as cobalt or gold) creates a weapon known as a salted bomb. This device can produce exceptionally large quantities of radioactive contamination. Most variety in nuclear weapon design is in different yields of nuclear weapons for different types of purposes, and in manipulating design elements to attempt to make weapons extremely small.[2]
Sunday, February 22, 2009
Nuclear weapon Of Pakistan
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"Atom bomb" redirects here. For the 1996 song by Fluke, see Atom Bomb (Fluke song).
The mushroom cloud of the atomic bombing of Nagasaki, Japan in 1945 rose some 18 kilometers (11 miles) above the bomb's hypocenter.
A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission or a combination of fission and fusion. Both reactions release vast quantities of energy from relatively small amounts of matter; a modern thermonuclear weapon weighing little more than a thousand kilograms can produce an explosion comparable to the detonation of more than a billion kilograms of conventional high explosive.[1] Even small nuclear devices can devastate a city. Nuclear weapons are considered weapons of mass destruction, and their use and control has been a major aspect of international policy since their debut.
In the history of warfare only two nuclear weapons have been detonated offensively, both near the end of World War II. The first was detonated on the morning of 6 August 1945, when the United States dropped a uranium gun-type device code-named "Little Boy" on the Japanese city of Hiroshima. The second was detonated three days later when the United States dropped a plutonium implosion-type device code-named "Fat Man" on the city of Nagasaki, Japan. These bombings resulted in the immediate deaths of around 120,000 people (mostly civilians) from injuries sustained from the explosion and acute radiation sickness, and even more deaths from long-term effects of (ionizing) radiation. The use of these weapons was and remains controversial. (See Atomic bombings of Hiroshima and Nagasaki for a full discussion.)
Since the Hiroshima and Nagasaki bombings, nuclear weapons have been detonated on over two thousand occasions for testing purposes and demonstration purposes. The only countries known to have detonated nuclear weapons – and that acknowledge possessing such weapons – are (chronologically) the United States, the Soviet Union (succeeded as a nuclear power by Russia), the United Kingdom, France, the People's Republic of China, India, Pakistan, and North Korea. Israel is also widely believed to possess nuclear weapons, though it does not acknowledge having them. For more information on these states' nuclear programs, as well as other states that formerly possessed nuclear weapons or are suspected of seeking nuclear weapons, see List of states with nuclear weapons.
Arsenal
The U.S.-based Natural Resources Defense Council (NRDC) estimates that Pakistan has built 24–48 HEU-based nuclear warheads with HEU reserves for 30-52 additional warheads.[9][10] The US Navy Center for Contemporary Conflict estimates that Pakistan possesses between a low of 35 and a high of 95 nuclear warheads, with a median of 60.[11] But these are outdated sources.
The NRDC's and the Carnegie Foundation's estimates of approximately 50 weapons are from 2002–03 estimations. In 2000, US Military intelligence estimated that Pakistan's nuclear arsenal may be as large as 100 warheads.[12] The actual size is hard for experts to gauge owing to the secrecy which surrounds the program in Pakistan. In recent developments, retired Brig. General Feroz Khan, previously second in command at the Strategic Arms Division of Pakistans' Military told a Pakistani newspaper the nation has "about 80 to 120 genuine warheads," and also revealed that Pakistan has decoy or dummy warheads to complicate any designs by aggressors.[13][14]
Pakistan tested plutonium capability in the sixth nuclear test of May 30, 1998 at Kharan. In this test, the latest and most sophisticated bomb design made to be carried by missiles was tested. And it was a very compact, yet powerful device.[citation needed] Compactness is also an issue with F-16s and other fighter-bomber aircraft of the same class, unless the platform happens to be a dedicated strategic bomber. F-16s have limits to the size and weight of the bombs they can carry.
The critical mass of a bare mass sphere of 90% enriched uranium-235 is 52 kg. Correspondingly, the critical mass of a bare mass sphere of Plutonium-239 is 8-10 kg. The bomb that destroyed Hiroshima used 60 kg of U-235 while the Nagasaki Pu bomb used only 6 kg of Pu-239. Since all Pakistani bomb designs are implosion-type weapons, they will typically use between 15-25 kg of U-235 for their cores. Reducing the amount of U-235 in cores from 60 kg in gun-type devices to 25 kg in implosion devices is only possible by using good neutron reflector/ tamper material such as beryllium metal, which increases the weight of the bomb. And the uranium like plutonium is only usable in the core of a bomb in metallic form. Add about 50 or so chemical high-explosive lenses, triggering circuits, and outer aluminum casing, all this adds to the overall weight of the device. Therefore if a bomb has to use only U-235, it will impose serious restrictions on the amount of U-235 that can be used, and the size of the bomb itself, thus restricting its explosive yield. True PAEC did develop bomb designs that could be carried by all PAF aircraft, but after years of effort and R&D, and then too, there were serious limitations on the further extent of miniaturization of the bombs. If Uranium is used as bomb fuel, it cannot be miniaturized beyond a certain point.
However, only 2–4 kg of plutonium is needed for the same device that would need 20–25 kg of U-235. Additionally, a few grams of tritium (a by-product of plutonium production reactors and thermonuclear fuel) can increase the overall yield of the bombs by a factor of three to four.
A whole range and variety of weapons using Pu-239 can be easily built, both for aircraft delivery and especially for missiles (in which U-235 cannot be used). So if Pakistan wants to be a nuclear power with an operational deterrent capability, both first and second strike, based on assured strike platforms like ballistic and cruise missiles (unlike aircraft), the only solution is with plutonium, which has been the first choice of every country that built a nuclear arsenal.
As for Pakistan's plutonium capability, it has always been there, from the early 1980s onwards. There were only two problems. One was that Pakistan did not want to be an irresponsible state and so did not divert spent fuel from the safeguarded KANUPP for reprocessing at New Labs. This was enough to build a whole arsenal of nuclear weapons straight away. So PAEC built its own plutonium and tritium production reactor at Khushab, beginning in 1985. The second one was allocation of resources.
Ultra-centrifugation for obtaining U-235 cannot be done simply by putting natural uranium through the centrifuges. It requires the complete mastery over the front end of the nuclear fuel cycle, beginning at uranium mining and refining, production of uranium ore or yellow cake, conversion of ore into uranium dioxide UO2 (which is used to make nuclear fuel for natural uranium reactors like Khushab and KANUPP), conversion of UO2 into uranium tetrafluoride UF4 and then into the feedstock for enrichment (UF6).
The complete mastery over fluorine chemistry and production of highly toxic and corrosive hydrofluoric acid and other fluorine compounds is required. The UF6 is pumped into the centrifuges for enrichment. The process is then repeated in reverse until UF4 is produced, leading to the production of uranium metal, the form in which U-235 is used in a bomb.
It is estimated that there are approximately 10,000 centrifuges in Kahuta. This means that with P2 machines, they would be producing between 75–100 kg of HEU since 1986, when full production of weapons-grade HEU began. Also the production of HEU was voluntarily capped by Pakistan between 1991 and 1997, and the five nuclear tests of May 28, 1998 also consumed HEU. So it is safe to assume that between 1986 and 2005 (prior to the 2005 earthquake), KRL produced 1500 kg of HEU. Accounting for losses in the production of weapons, it can be assumed that each weapon would need 20 kg of HEU; sufficient for 75 bombs.
Pakistan's first nuclear tests were made in May 1998, when six warheads were tested. It is reported that the yields from these tests were 12 kt of TNT, 30 to 35 kt of TNT and four low-yield (below 1 kt of TNT) tests. From these tests Pakistan can be estimated to have developed operational warheads of 20 to 25 kt and 150 kt of TNT in the shape of low weight compact designs and may have 300–500 kt of TNT large-size warheads. The low-yield weapons are probably in nuclear bombs carried on F-16 Fighting Falcon aircraft and fitted to Pakistan's short-range ballistic missiles, while the higher-yield warheads are probably fitted to the Shaheen and Ghauri ballistic missiles.
The NRDC's and the Carnegie Foundation's estimates of approximately 50 weapons are from 2002–03 estimations. In 2000, US Military intelligence estimated that Pakistan's nuclear arsenal may be as large as 100 warheads.[12] The actual size is hard for experts to gauge owing to the secrecy which surrounds the program in Pakistan. In recent developments, retired Brig. General Feroz Khan, previously second in command at the Strategic Arms Division of Pakistans' Military told a Pakistani newspaper the nation has "about 80 to 120 genuine warheads," and also revealed that Pakistan has decoy or dummy warheads to complicate any designs by aggressors.[13][14]
Pakistan tested plutonium capability in the sixth nuclear test of May 30, 1998 at Kharan. In this test, the latest and most sophisticated bomb design made to be carried by missiles was tested. And it was a very compact, yet powerful device.[citation needed] Compactness is also an issue with F-16s and other fighter-bomber aircraft of the same class, unless the platform happens to be a dedicated strategic bomber. F-16s have limits to the size and weight of the bombs they can carry.
The critical mass of a bare mass sphere of 90% enriched uranium-235 is 52 kg. Correspondingly, the critical mass of a bare mass sphere of Plutonium-239 is 8-10 kg. The bomb that destroyed Hiroshima used 60 kg of U-235 while the Nagasaki Pu bomb used only 6 kg of Pu-239. Since all Pakistani bomb designs are implosion-type weapons, they will typically use between 15-25 kg of U-235 for their cores. Reducing the amount of U-235 in cores from 60 kg in gun-type devices to 25 kg in implosion devices is only possible by using good neutron reflector/ tamper material such as beryllium metal, which increases the weight of the bomb. And the uranium like plutonium is only usable in the core of a bomb in metallic form. Add about 50 or so chemical high-explosive lenses, triggering circuits, and outer aluminum casing, all this adds to the overall weight of the device. Therefore if a bomb has to use only U-235, it will impose serious restrictions on the amount of U-235 that can be used, and the size of the bomb itself, thus restricting its explosive yield. True PAEC did develop bomb designs that could be carried by all PAF aircraft, but after years of effort and R&D, and then too, there were serious limitations on the further extent of miniaturization of the bombs. If Uranium is used as bomb fuel, it cannot be miniaturized beyond a certain point.
However, only 2–4 kg of plutonium is needed for the same device that would need 20–25 kg of U-235. Additionally, a few grams of tritium (a by-product of plutonium production reactors and thermonuclear fuel) can increase the overall yield of the bombs by a factor of three to four.
A whole range and variety of weapons using Pu-239 can be easily built, both for aircraft delivery and especially for missiles (in which U-235 cannot be used). So if Pakistan wants to be a nuclear power with an operational deterrent capability, both first and second strike, based on assured strike platforms like ballistic and cruise missiles (unlike aircraft), the only solution is with plutonium, which has been the first choice of every country that built a nuclear arsenal.
As for Pakistan's plutonium capability, it has always been there, from the early 1980s onwards. There were only two problems. One was that Pakistan did not want to be an irresponsible state and so did not divert spent fuel from the safeguarded KANUPP for reprocessing at New Labs. This was enough to build a whole arsenal of nuclear weapons straight away. So PAEC built its own plutonium and tritium production reactor at Khushab, beginning in 1985. The second one was allocation of resources.
Ultra-centrifugation for obtaining U-235 cannot be done simply by putting natural uranium through the centrifuges. It requires the complete mastery over the front end of the nuclear fuel cycle, beginning at uranium mining and refining, production of uranium ore or yellow cake, conversion of ore into uranium dioxide UO2 (which is used to make nuclear fuel for natural uranium reactors like Khushab and KANUPP), conversion of UO2 into uranium tetrafluoride UF4 and then into the feedstock for enrichment (UF6).
The complete mastery over fluorine chemistry and production of highly toxic and corrosive hydrofluoric acid and other fluorine compounds is required. The UF6 is pumped into the centrifuges for enrichment. The process is then repeated in reverse until UF4 is produced, leading to the production of uranium metal, the form in which U-235 is used in a bomb.
It is estimated that there are approximately 10,000 centrifuges in Kahuta. This means that with P2 machines, they would be producing between 75–100 kg of HEU since 1986, when full production of weapons-grade HEU began. Also the production of HEU was voluntarily capped by Pakistan between 1991 and 1997, and the five nuclear tests of May 28, 1998 also consumed HEU. So it is safe to assume that between 1986 and 2005 (prior to the 2005 earthquake), KRL produced 1500 kg of HEU. Accounting for losses in the production of weapons, it can be assumed that each weapon would need 20 kg of HEU; sufficient for 75 bombs.
Pakistan's first nuclear tests were made in May 1998, when six warheads were tested. It is reported that the yields from these tests were 12 kt of TNT, 30 to 35 kt of TNT and four low-yield (below 1 kt of TNT) tests. From these tests Pakistan can be estimated to have developed operational warheads of 20 to 25 kt and 150 kt of TNT in the shape of low weight compact designs and may have 300–500 kt of TNT large-size warheads. The low-yield weapons are probably in nuclear bombs carried on F-16 Fighting Falcon aircraft and fitted to Pakistan's short-range ballistic missiles, while the higher-yield warheads are probably fitted to the Shaheen and Ghauri ballistic missiles.
Nuclear weapons
Policy
Pakistan acceded to the Geneva Protocol on April 15, 1960, the Biological Weapons Convention in 1974 and the Chemical Weapons Convention on October 28, 1997.In 1999 Pakistan signed the Lahore Accords with India, agreeing on a bilateral moratorium on nuclear testing. However, Pakistan, like India and Israel, is not a signatory of the Non-Proliferation Treaty and, consequently, not bound by any of its provisions. Some Pakistani nuclear scientists have been reported by the CIA to be involved in the proliferation of nuclear weapons technology. In particular, one of Pakistan's chief nuclear scientists, Dr. A.Q. Khan, has admitted his role in nuclear proliferation, but since Pakistan is not a signatory of NPT, there is no breakage of International laws.
Infrastructure
Pakistan's nuclear weapons development program is based, primarily, on highly-enriched uranium (HEU), which is produced at the Kahuta Research Laboratories at Kahuta, a Zippe centrifuge-based uranium-enrichment facility. The Kahuta facility has been in use since the early 1980s. By the early 1990s, Kahuta had an estimated 3,000 centrifuges in operation, and Pakistan has continued its pursuit of expanded uranium-enrichment capabilities.
In the mid 1980s, Pakistan Atomic Energy Commission began to pursue Plutonium production capabilities. Consequently Pakistan built the 40-50 MW (megawatt, thermal) Khushab Research Reactor at Joharabad, and in April 1998, Pakistan announced that the nuclear reactor was operational. The Khushab reactor project was initiated in 1986 by PAEC chairman Munir Ahmad Khan, who insisted that the reactor was totally indigenous, i.e. that it was designed and built by Pakistani scientists and engineers. Pakistani industry contributed in 82% of the reactor's construction. The Project-Director for this project was Sultan Bashiruddin Mahmood. According to public statements made by the US Government officials, this heavy-water reactor can produce up to 8 to 10 kg of plutonium per year,[3] sufficient for at least one nuclear weapon.[4] The reactor could also produce tritium if it were loaded with lithium-6, although this is unnecessary for the purposes of nuclear weapons, because modern nuclear weapon designs use 6Li directly. According to J. Cirincione of Carnegie Endowment for International Peace, Khushab's Plutonium production capacity could allow Pakistan to develop lighter nuclear warheads that would be easier to deliver through ballistic missiles.[citation needed]
Plutonium separation, reportedly, takes place at the New Labs Reprocessing Plant, which was completed by 1981 by PAEC and is next to the Pakistan Institute of Nuclear Science and Technology (PINSTECH) near Islamabad, which is not subject to IAEA inspections and safeguards.
Television screenshot of the first known Pakistani Nuclear Test, 28 May 1998.
In late 2006, the US Institute for Science and International Security released intelligence reports and imagery showing the construction of a new plutonium reactor at the Khushab nuclear site. The reactor is deemed to be large enough to produce enough plutonium to facilitate the creation of as much as "40 to 50 nuclear weapons a year."[5][6][7] The New York Times carried the story with the insight that this would be Pakistan's third plutonium reactor[8], signalling a shift to dual-stream development, with Plutonium-based devices supplementing the nation's existing HEU stream to atomic warheads.
In the mid 1980s, Pakistan Atomic Energy Commission began to pursue Plutonium production capabilities. Consequently Pakistan built the 40-50 MW (megawatt, thermal) Khushab Research Reactor at Joharabad, and in April 1998, Pakistan announced that the nuclear reactor was operational. The Khushab reactor project was initiated in 1986 by PAEC chairman Munir Ahmad Khan, who insisted that the reactor was totally indigenous, i.e. that it was designed and built by Pakistani scientists and engineers. Pakistani industry contributed in 82% of the reactor's construction. The Project-Director for this project was Sultan Bashiruddin Mahmood. According to public statements made by the US Government officials, this heavy-water reactor can produce up to 8 to 10 kg of plutonium per year,[3] sufficient for at least one nuclear weapon.[4] The reactor could also produce tritium if it were loaded with lithium-6, although this is unnecessary for the purposes of nuclear weapons, because modern nuclear weapon designs use 6Li directly. According to J. Cirincione of Carnegie Endowment for International Peace, Khushab's Plutonium production capacity could allow Pakistan to develop lighter nuclear warheads that would be easier to deliver through ballistic missiles.[citation needed]
Plutonium separation, reportedly, takes place at the New Labs Reprocessing Plant, which was completed by 1981 by PAEC and is next to the Pakistan Institute of Nuclear Science and Technology (PINSTECH) near Islamabad, which is not subject to IAEA inspections and safeguards.
Television screenshot of the first known Pakistani Nuclear Test, 28 May 1998.
In late 2006, the US Institute for Science and International Security released intelligence reports and imagery showing the construction of a new plutonium reactor at the Khushab nuclear site. The reactor is deemed to be large enough to produce enough plutonium to facilitate the creation of as much as "40 to 50 nuclear weapons a year."[5][6][7] The New York Times carried the story with the insight that this would be Pakistan's third plutonium reactor[8], signalling a shift to dual-stream development, with Plutonium-based devices supplementing the nation's existing HEU stream to atomic warheads.
Pakistan and weapons of mass destruction
The Islamic Republic of Pakistan began focusing on nuclear development in January 1972 under the leadership of Prime Minister Zulfiqar Ali Bhutto (father of Benazir Bhutto). Pakistan's nuclear weapons development program was in response to neighboring India's development of nuclear weapons. Prime minister Bhutto called a meeting of senior scientists and engineers on January 20, 1972, in Multan. It was here that Prime Minister Bhutto rallied Pakistan's scientists to build the atomic bomb for national survival. At the Multan meeting, Prime Minister Bhutto also appointed a Pakistani nuclear Scientist, Munir Ahmad Khan, as chairman of Pakistan Atomic Energy Commission (PAEC), who till then had been working as Director of Nuclear Power and Reactor Division at the International Atomic Energy Agency (IAEA), in Vienna, Austria. This marked the beginning of Pakistan's pursuit of nuclear capability. Following India's surprise nuclear test, codenamed Smiling Buddha in 1974, the first confirmed nuclear test by a nation outside the permanent five members of the United Nations Security Council, the goal to develop nuclear weapons received considerable impetus.
Consequently, Dr. Abdul Qadeer Khan, a metallurgical engineer, working at the Dutch research firm URENCO, also joined Pakistan's nuclear weapons-grade Uranium enrichment program, using stolen URENCO designs. The uranium enrichment program had been launched in 1974 by PAEC chairman Munir Ahmad Khan as Project-706. AQ Khan joined the project in the spring of 1976 and was made Project-Director in July 1976 after taking over from another Nuclear Scientist Sultan Bashiruddin Mahmood. In 1983, Khan was convicted of the theft of the blueprints, though the conviction was overturned on a legal technicality.[1]
A few weeks after India's second nuclear test (Operation Shakti) on 28 May 1998, Pakistan detonated five nuclear devices in the Chagai Hills in the Chaghai district, Balochistan. This operation was named Chagai-I by Pakistan, the base having been long-constructed by provincial martial law administrator Rahimuddin Khan during the 1980s. Pakistan's fissile material production takes place at Kahuta and Khushab/Jauharabad, where weapons-grade plutonium is made, allegedly with using Chinese-supplied technology.[2]
Pakistan's Nuclear Weapons Program was established in 1974 when the Directorate of Technical Development (DTD) was set up in PAEC by chairman Munir Ahmad Khan, who was credited as the one of the pioneer of Pakistan's atomic bomb by a recent IISS, London's Dossier on Pakistan's nuclear program. DTD was assigned the task of developing the implosion design, trigger mechanism, physics calculations, high-speed electronics, high-precision chemical and mechanical components, high explosive lenses for Pakistan's nuclear weapons. The DTD had come up with its first implosion design of a nuclear weapon by 1978 which was then improved and later tested on March 11, 1983 when PAEC carried out Pakistan's first successful cold test of a nuclear device. Between 1983 and 1990, PAEC carried out 24 more cold tests of various nuclear weapon designs. DTD had also developed a miniaturized weapon design by 1987 that could be delivered by all Pakistan Air Force Aircraft
Consequently, Dr. Abdul Qadeer Khan, a metallurgical engineer, working at the Dutch research firm URENCO, also joined Pakistan's nuclear weapons-grade Uranium enrichment program, using stolen URENCO designs. The uranium enrichment program had been launched in 1974 by PAEC chairman Munir Ahmad Khan as Project-706. AQ Khan joined the project in the spring of 1976 and was made Project-Director in July 1976 after taking over from another Nuclear Scientist Sultan Bashiruddin Mahmood. In 1983, Khan was convicted of the theft of the blueprints, though the conviction was overturned on a legal technicality.[1]
A few weeks after India's second nuclear test (Operation Shakti) on 28 May 1998, Pakistan detonated five nuclear devices in the Chagai Hills in the Chaghai district, Balochistan. This operation was named Chagai-I by Pakistan, the base having been long-constructed by provincial martial law administrator Rahimuddin Khan during the 1980s. Pakistan's fissile material production takes place at Kahuta and Khushab/Jauharabad, where weapons-grade plutonium is made, allegedly with using Chinese-supplied technology.[2]
Pakistan's Nuclear Weapons Program was established in 1974 when the Directorate of Technical Development (DTD) was set up in PAEC by chairman Munir Ahmad Khan, who was credited as the one of the pioneer of Pakistan's atomic bomb by a recent IISS, London's Dossier on Pakistan's nuclear program. DTD was assigned the task of developing the implosion design, trigger mechanism, physics calculations, high-speed electronics, high-precision chemical and mechanical components, high explosive lenses for Pakistan's nuclear weapons. The DTD had come up with its first implosion design of a nuclear weapon by 1978 which was then improved and later tested on March 11, 1983 when PAEC carried out Pakistan's first successful cold test of a nuclear device. Between 1983 and 1990, PAEC carried out 24 more cold tests of various nuclear weapon designs. DTD had also developed a miniaturized weapon design by 1987 that could be delivered by all Pakistan Air Force Aircraft
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