China tested nukes for Pakistan, gave design - Times of India
US News: The US and the West were aware of Chinese nuclear weapons proliferation to Pak, including conducting a proxy test for it, as far back as 1990, an ex-U
timesofindia.indiatimes.com
Pakistan’s nuclear forces, 2011 - Hans M. Kristensen, Robert S. Norris, 2011
The US raid that killed Osama bin Laden has raised concerns about the security of Pakistan’s nuclear arsenal. In the process of building two new plutonium produ...
journals.sagepub.com
Why don't Iran ask China for nukes?
How much plutonium or uranium is needed for a Pakistani nuclear warhead depends upon many variables, but three are particularly important: the technical capabilities of the scientists and engineers, the warhead design, and the desired yield (see Table 2). Skilled technicians need less fissile material to achieve a given yield. Though we do not know the skill level at which the Pakistani bomb designers are working, they have been at it since the 1970s, have had help from China, and have conducted several nuclear tests; these factors suggest that low- to medium-level technical skills are plausible.
Precise details about Pakistan’s nuclear warheads are not publicly known, but its initial warhead design was most likely an HEU fission implosion configuration. There is general consensus that China provided Pakistani nuclear scientist A. Q. Khan with the blueprints to the uranium implosion device that China detonated on October 27, 1966 (the so-called CHIC-4 test/design). It is also generally accepted that on May 26, 1990, China tested a Pakistani derivative of the CHIC-4 at its Lop Nor test site, with a yield in the 10–12 kiloton (kt) range.3 That range accords with estimates of Pakistan’s 1998 nuclear tests, which had yields somewhere between 5 and 12 kt. Refinements in boosting and plutonium use are the normal next steps in weapon improvements, along with miniaturization of the warheads to fit into smaller delivery vehicles. Pakistan is probably undertaking all of these improvements to arm its cruise and ballistic missiles, or both, with smaller payloads.
Pakistan may be producing 120–180 kg of HEU per year, an amount sufficient for 7–15 warheads. The uranium ore is mined at several locations throughout Pakistan, with more mines scheduled to open in the future. Uranium is extracted from the ore and processed into uranium hexafluoride and uranium metal at the Dera Ghazi Khan uranium processing facility in southern Punjab. Enrichment takes place at the Kahuta and Gadwal plants southeast and northwest of Islamabad, respectively (International Panel on Fissile Materials, 2010; Landay, 2009; US Department of Commerce, 1998).
