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All five atomic devices were spherical-implosion-type nuclear weapons
|Test site||Ras Koh Hills, Chagai, Balochistan, Pakistan|
|Number of tests||5|
|Test type||Underground tests|
|Max. yield||40 kilotons of TNT (170 TJ)
Chagai-I is the code name of five simultaneous underground nuclear tests conducted by Pakistan at 15:15 hrs PST on 28 May 1998. The tests were performed at Ras Koh Hills in the Chagai District of Balochistan Province in Pakistan.
Chagai-I, Pakistan's first public nuclear test, was a direct response to India's second nuclear tests, Operation Shakti, on 11 and 13 May 1998. These nuclear weapon tests by Pakistan and India resulted in United Nations Security Council Resolution 1172 and economic sanctions on both states by a number of major powers, particularly the United States and Japan. With the testing of the five nuclear devices, Pakistan became the seventh nuclear power in the world to successfully develop and publicly test nuclear weapons, despite international outcry.
- 1 Origin
- 2 Planning and preparation
- 3 Development teams
- 4 Reaction in Pakistan
- 5 International reaction
- 6 See also
- 7 References
- 8 Further information
- 9 External links
After the Partition of India in 1947, India and Pakistan have been in conflict over the disputed territory of Azad Jammu and Kashmir, including two openly declared wars, the Indo-Pakistani War of 1947 and the Indo-Pakistani War of 1965.
After the Indo-Pakistan war in 1965, the military embargo by the United States and the Central Treaty Organization (CENTO) alliance with the West through NATO endangered Pakistan's national security, eventually leading to the offset of their conventional weapon shortcomings against India, while countering India's nuclear program that started in 1967. Slow efforts for developing nuclear power in the country were put forward by Dr. I. H. Usmani who kept the program strictly directed towards anti-nuclear weapons development. In 1969, the Pakistan Atomic Energy Commission (PAEC) successfully negotiated with the United Kingdom Atomic Energy Authority (AEA) for the supply of a nuclear reprocessing site capable of extracting 360 grams (13 oz) of weapons-grade plutonium annually. A five-member delegation led by geophysicist, Dr. Ahsan Mubarak, received training to gain expertise in the nuclear fuel cycle as they secretively learned about weapons-grade and reactor-grade plutonium. Agreements were made with Atomic Energy of Canada Limited (AECL), Commissariat à l'énergie atomique (CEA) and British Nuclear Fuels (BNFL) to expand Pakistan's nuclear power infrastructure as part of their peaceful nuclear policy. During this time, Pakistan had built a very strong background in theoretical physics and key research on the field was being directed by the universities in Pakistan.
The 1971 war and atomic bomb projects
The main impetus for Pakistan's development of nuclear weapons was a need to prevent a repetition of the effects of the Indo-Pakistani war of 1971, which led to the loss of East Pakistan (now Bangladesh) in the Bangladesh Liberation War, and the surrender of the Pakistan Eastern Command of approximately 93,000 as prisoners of war (POWs) to India. Eventually, these POWs were repatriated to Pakistan under the provisions of the Simla Agreement but the decisive defeat left deep scars in Pakistan's civil society. Given the failure of the country's foreign policy to gather support from long-standing allies, such as the United States, Turkey, and China, Pakistan's physical existence seemed to depend upon its own initiative.
The war played a groundbreaking role in the hearts of the scientists of the country who witnessed it and they dedicated themselves to developing the potential nuclear deterrent. The concurrent rise of anti-Pakistan governments in South Asia and India led to a fear of India's nuclear program, which started in 1967. On 20 January 1972, the President of Pakistan Zulfikar Ali Bhutto chaired a winter seminar, the "Multan meeting", and supported the all-out efforts for building a nuclear deterrent. This crash program came as a direct consequences of India's nuclear program and President Bhutto's obsession towards it.
As Abdus Salam consolidated his position in the government and Munir Ahmad Khan returning to Pakistan from the International Atomic Energy Agency (IAEA) to lead the crash program, the efforts were transferred to the authority of the PAEC. The weapons development portion for this project was located at 20 special weapons' labs overseen by the PAEC. Development and designing took place with the foundation of the Theoretical Physics Group (TPG) led by Abdus Salam and Mathematics division led by Razi Siddiqui at PAEC; all engaging in the fast-neutron calculations. Physical developments were eventually carried out by "Wah Group Scientists" led by Hafeez Qureshi and Dr. Zaman Sheikh (a chemical engineer) at the Metallurgical Laboratory located in Wah in March 1974. Logistics and coordination between each secret site were overseen by the Directorate of Technical Development (DTD) under Zaman Sheikh.
Enormous production of weapons-grade plutonium and uranium was undertaken by the PAEC that accounted for more focus towards weapon-grade plutonium. Plutonium is a synthetic element with complicated physio-chemical and metallurgical properties; it is not found in nature in appreciable quantities. The program accelerated when India eventually surprising the world with its first nuclear test in 1974; the development of the atomic bombs became impetus. The uranium enrichment program was eventually separated from the PAEC when Abdul Qadeer Khan founded the Engineering Research Laboratories (ERL) and authority transferred from the PAEC to the military. The enrichment of uranium is a difficult and enduring approach to scale to industrial levels to military-grade; only 0.71 percent of natural uranium (Unat) was uranium-235 (U235), and it was estimated that it would take 27,000 years to produce 1 gram (0.035 ounce) of uranium with mass spectrometers, but kilogram (2.2 pound-35 oz) amounts were required.
The program turned to an alternative, albeit more technically difficult design– an implosion-type method compared to the relatively simple gun-type method. In 1977, the TPG concluded its fast-neutron calculations and the first implosion-type design was completed in 1978 by MPG. With electromagnetic isotope separation starting 1976, military-grade highly enriched uranium (HEU) was successfully achieved by ERL in 1981.
On 11 March 1983, a milestone was achieved when PAEC, led by Munir Ahmad Khan, carried out the first cold test of a working nuclear device, codename Kirana-I, which continued by having 24 more cold tests from 1983–94. After decades of covertly developing their atomic weapons program, the Pokhran-II nuclear tests by India, their second, provided an opportunity for Pakistan to reciprocate with its own tests in Chagai Hills.
Planning and preparation
Plans to conduct an atomic test started in 1974 when PAEC's research scientists frequently visiting the area to find a suitable location for an underground nuclear test, preferably a granite mountain located in Balochistan. This was done due to the country being party to the Partial Nuclear Test Ban Treaty; an exoatmospheric or atmospheric test was not an option.
After a long survey, the PAEC scientists chose the mountain in Koh Kambaran located in the Ras Koh Hills in the Chagai Division of Balochistan in 1978. Its highest point rises to a height of 3,009 metres (sources vary). Safety and security required a remote, isolated and unpopulated mountainous area. The PAEC's requirement was that the mountain should be "bone dry" and capable of withstanding a 20–40 kilotonne (kt) detonation from the inside. The scientists also wanted dry weather, and very little wind to spread radioactive fallout.
For this purpose, the Geological Survey of Pakistan (GSP) conducted tests to measure the water content of the mountains in the surrounding area and to measure the capability of the mountain's rock to withstand the force of a nuclear test. The Governor of Balochistan, General Rahimuddin Khan, spearheaded the civil engineering of the potential test sites throughout the 1980s.
In 2005 Benazir Bhutto testified that "Pakistan may have had an atomic device long before, and her father had told her from his prison cell that preparations for a nuclear test had been made in 1977, and he expected to have an atomic test of a nuclear device in August 1977." However, the plan was moved on to December 1977 and later it was delayed indefinitely to avoid international reaction; thus obtaining deliberate ambiguity. In an interview with Hamid Mir in Capital Talk which aired on Geo News in 2005, Dr. Samar Mubarakmand confirmed Bhutto's testimony and maintained that PAEC developed the design of an atomic bomb in 1978 and had successfully conducted a cold test after building the first atomic bomb in 1983.
On 13–15 May 1998, Indian Prime Minister Atal Bihari Vajpayee announced the Pokhran-II nuclear tests conducted in Rajasthan while celebrating the event. It was a time of tense atmosphere with the statements of Indian politicians further escalating the situation in South Asia. Prime Minister Nawaz Sharif curtailed his state visit to Kazakhstan to meet with the President Nursultan Nazarbayev and returned to Pakistan. Decision to conduct tests took place when Sharif convened meeting with Chairman joint chiefs, General Jehangir Karamat, Dr. Abdul Qadeer Khan, Ishfaq Ahmad, and Munir Ahmad Khan and other members of his Cabinet. In talks with Sharif, U.S. President Bill Clinton offered a lucrative aid package in an attempt to get Pakistan to refrain from nuclear testing, and sent high level civic-military delegations led by Strobe Talbott and General Anthony Zinni to Pakistan to lobby against the tests. Popular public opinion in Pakistan was in favor of nuclear blasts. Information minister Mushahid Hussain was the first who argued for the tests in reply to the Indian nuclear tests. Opposition leader Benazir Bhutto immediately called for Pakistani atomic tests and publicly lobbied in favor of them; thus putting more political pressure on Prime Minister Nawaz Sharif.
At the NSC's cabinet meeting, the Pakistani government, military, scientific, and civilian officials were participating in a debate, broadening, and complicating the decision-making process. Chairman joint chiefs, General Karamat and Air chief ACM Parvaiz Mehdi Qureshi supported the matter and left the decision on the government. Naval chief Admiral Fasih Bokhari and Finance Minister Sartaj Aziz argued against the tests on financial grounds; though Aziz later staunchly backed the decision to test calling it as "right decision." Dr. Abdul Qadeer Khan argued in favor of tests and was supported by Samar Mubarakmand and Munir Ahmad Khan while Dr. Ishfaq Ahmad argued that "the decision to test or not to test was that of the Government of Pakistan despite the say of the scientific community." Concluding the final arguments, Ishfaq Ahmad said: "Mr. Prime Minister, take a decision and, Insha'Allah, I give you the guarantee of success".
With the G8 group's sanctions having very little effect on India and skepticism towards U.S. commitment, the Pakistani government economists built up the final consensus hardening around the idea that "there is no economic price for security". Despite being under pressure by U.S. President Bill Clinton, Prime Minister Sharif authorized the nuclear tests by ordering the PAEC in Urdu: "Dhamaka kar dein" (lit. "Conduct the explosion!")
In 1999, in an interview given to Pakistani and Indian journalists in Islamabad, Sharif had said: If India had not exploded the bomb, Pakistan would not have done so. Once New Delhi did so, We [Sharif Government] had no choice because of public pressure.
Predicted yield and blast measurement
The observation post was established about 10 km (≈6.21 miles) from the test vicinity, with members of Mathematics Group and Theoretical Physics Group (TPG) led by Dr. Masud Ahmad and Asghar Qadir charged with calculating the yields. Determining the accurate and precise blast yields and shock waves are very hard to calculate even in a control environmental system, with many different possible ways the yields can be determined. The questions of politics also further disputed the exact figures. The TPG predicted the total maximum test yields with an energy equivalent to be ~40 kilotons of TNT equivalent, with the largest (boosted) device yielding 30–36 kilotons. The American scientists, however, contested the yield results by approximating the yields at 6–13 kilotons. American physicists, based on the seismic wave data they received from their computers, claimed that the possible yield ranged from 12–20 kt as opposed to approximately 40 kt determined by physicists of the Pakistan Government.
The PAEC's mathematics division placed the scientific data in the public domain and published seismic activities, mathematical graphs, and mathematical formulas used to calculate the yield; though the scientific information remains classified. After the tests, Prime Minister Nawaz Sharif addressed the nation via the Pakistani government's state owned channel Pakistan Television (PTV), congratulated the entire nation and days of celebration followed throughout Pakistan.
From scientific data received by PAEC, it appears that Pakistan did not test a thermonuclear device, as opposed to India. According to Ishfaq Ahmad, the PAEC had no plans to develop a hydrogen device for economic reasons, even though back in 1974, Riazuddin did propose such a plan to Abdus Salam, Director of Theoretical Physics Group that time. From the outset, PAEC concentrated on developing smaller tactical nuclear weapons easily installed on Pakistan Air Force (PAF) aircraft, Pakistan Navy combatant vessels, and missiles.
Shortly after the tests, former chairman and technical director Munir Ahmad Khan famously quoted: "These boosted devices are like a half way stage towards a thermonuclear bomb. They use elements of the thermonuclear process, and are effectively stronger atom bombs..... Pakistan has had a nuclear capability since 1984 and all the Pakistani devices were made with enriched uranium."
On the other hand, Abdul Qadeer Khan further provided technical details on fission devices while addressing the local media as he puts it: "All boosted fission devices using Uranium 235 on 28 May. None of these explosions were thermonuclear, we are doing research and can do a fusion test if asked. But it depends on the circumstances, political situation and the decision of the government. As opposed to India's thermonuclear approach, Dr. N. M. Butt, senior scientist, stated that "PAEC built a sufficient number of neutron bombs— a battlefield weapon that is essentially a low yield device".
Pakistan Atomic Energy Commission (PAEC)
- Ishfaq Ahmad, Chairman of the PAEC.
- Samar Mubarakmand, Member (Technical), PAEC
- Anwar Ali, Directorate of Technical Equipment (DTE).
- Hafeez Qureshi, Head of Directorate of Technical Development (DTD)
- N. A. Javed, Director of Directorate of Quality Assurance (DQA).
- Irfan Burney, Director of Directorate of Technical Procurement (DTP).
- I. A. Bhatty, Director of Directorate of Industrial Liaison (DIL)
- Tariq Salija, Director of the Radiation and Isotope Applications Division (RIAD).
- Muhammad Jameel, Director of Directorate of Science and Engineering Services (DSES)
- Muhammad Arshad, the Chief Scientific Officer (CSO).
- Masud Ahmad, Theoretical Physics Group
Kahuta Research Laboratories (KRL)
- Abdul Qadeer Khan, Director General of Khan Research Laboratories (KRL).
- M. Nasim Khan, Director of Material Science and Engineering Division (MSE).
- S. Mansoor Ahmed, Director of Uranium Enrichment Technology Division (UET).
- Fakhr Hashmi, Director of Molecular-Laser Enrichment Technology Division (MLET).
- Javed Ashraf Mirza, Director of Control and Guidance Division (CGD).
- Tasneem M. Shah, Director of Computational Fluid Dynamics Division (CFD).
Pakistan Army Corps of Engineers (PACE)
- Lieutenant-General Zulfikar Ali Khan — Engineer-in-Chief of the Pakistan Army Corps of Electrical and Mechanical Engineering and the System and Combat Engineering Division of the Pakistan Army Corps of Engineers
Reaction in Pakistan
The Directorate of Technical Development of PAEC which carried out the Chagai tests issued the following statement soon after the tests:
|“||The mission has, on the one hand, boosted the morale of the Pakistani nation by giving it an honorable position in the nuclear world, while on the other hand it validated scientific theory, design and previous results from cold tests. This has more than justified the creation and establishment of DTD more than 20 years back.
These gifted scientists and engineers along with a highly dedicated team worked logically and economically to design, produce and test an extremely rugged device for the nation which enable the Islamic Republic of Pakistan from strength to strength.
Effects on science
After the test, the national media in Pakistan posted biographies of the involved scientists. Senior scientists and engineers were invited by a number of academic institutes and universities to deliver lectures on mathematical, theoretical, nuclear and particle physics. The institutes bestowed hundreds of silver and gold medallions and honorary doctorates to the scientists and engineers in 1998.
Abdus Salam (1926–1996) was awarded the Nobel Prize in Physics in 1979 for the discovery of electroweak interaction. In 1998, the Government of Pakistan issued a commemorative stamp in his honour. In 1999, the government established a museum at the National Center for Physics, where Salam's contribution to scientific programs and efforts were recorded and televised.
Signed into law by Prime Minister Nawaz Sharif, 28 May is officially declared as Youm-e-Takbeer (lit. Day of Greatness), as well as National Science Day, to commemorate the date of the first five tests and honour the scientific efforts to develop the program. The day is celebrated by giving awards (such as Chagai-Medal) to various individuals and industries in the field of science and industries. The Pakistani government established the Chagai-I Medal, first awarded in 1998 to the scientists who witnessed the tests. The graphite mountains are visibly shown in the gold medallion and equal ribbon stripes of yellow, red and white.
The Chagai-I tests were condemned by the European Union, the United States, Japan, Iraq, and by the many non-Organisation of Islamic Cooperation (OIC) nations. The United Nations Security Council adopted "Resolution 1172", condemning the tests by both India and Pakistan. From 1998–99, the U.S. held a series of talks with Pakistan to persuade them to become party to the Comprehensive Nuclear-Test-Ban Treaty (CTBT) and the Non-Proliferation Treaty (NPT), with Pakistan refusing amid a fear of lack of security commitment by the U.S. and the growing ties between India and the United States.
The U.S., Japan, Australia, Sweden, Canada, and International Monetary Fund (IMF) imposed economic sanctions on Pakistan. The Japanese government recalled its ambassador from Pakistan, and suspended its relations with Pakistan. On the other hand, Saudi Arabia, Turkey, and Iran congratulated Pakistan where the major celebration took place.
All new U.S. economic assistance to Pakistan was suspended in May 1998 though the humanitarian aid continued. The composition of assistance to Pakistan shifted from monetary grants toward loans repayable in foreign exchange.
In the long term, the sanctions were eventually permanently lifted by the U.S. after Pakistan became a front line ally in the war against terror in 2001. Having improved its finances, the Pakistani government ended its IMF program in 2004.
- Zulfikar Ali Bhutto, Prime minister and colloquially known as the father of Pakistan nuclear weapons program.
- Nawaz Sharif, Pakistan's Prime Minister at that time,
- Abdus Salam, embarked the nuclear weapons program and director of Theoretical Physics Division
- Riazuddin, designer of Pakistan's thermo-nuclear devices.
- Asghar Qadir, led mathematical calculations involved in the nuclear devices.
- Munir Ahmad Khan, technical director and developed Pakistan's nuclear fuel cycle, nuclear weapons and energy programs.
- Ishfaq Ahmad, nuclear weapon designer and the Chairman of PAEC at that time.
- Abdul Qadeer Khan, developed the centrifuge technology used in enriching uranium hexafluoride gas for Pakistan.
- Samar Mubarakmand, Director of Fast-Neutron Physics Group and supervised the atomic tests at Chagai
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