Obituary of Vladislav Mokhov (1931-2011)

Professor Vladislav Nikolaevich Mokhov, who played a key role in the development of Soviet nuclear charges for peaceful applications and who played a key role in establishing post-Cold-War scientific relations with the United States, died in Sarov, Russia, on December 27, 2011 after suffering a stroke. Prior to a 2009 stroke, Slava was a Deputy Scientific Leader and former theoretical division leader at the All-Russian Scientific Research Institute of Experimental Physics (VNIIEF) at Sarov (formerly Arzamas-16), “the Russian Los Alamos” where the first nuclear weapons of the Soviet Union were developed.

Slava was born on April 12, 1931 in Atkarsk, Saratov region, Russia. He graduated from the Moscow Engineering and Physics Institute in 1955 and was selected by Ya. B. Zeldovich and A. D. Sakharov to join the Soviet Union’s nuclear weapons program at VNIIEF. Although Slava was reluctant to go to a “box” (a cynical shortening of “P. O. Box” used as the address for “closed” institutes, including the US’ Los Alamos), Zeldovich insisted that Slava’s talents were absolutely needed. Recognizing that resistance was futile, Slava’s advisor, Prof. Migdal, told him “then go there … at least you will know for what theoretical physics is needed.”

At VNIIEF, Slava quickly made a number of major contributions to the development of Soviet thermonuclear weapons. In 1963 he received his Candidate’s degree in physics and mathematics for work carried out in the early 1960’s on the development of the theory of turbulent mixing in layered structures under intense compression. After analyzing several failed experimental efforts, Slava theoretically identified the criteria for thermonuclear fuel ignition. In 1963, Slava was also awarded the Lenin prize for his work focused on the development of a novel thermonuclear secondary.

Slava was a VNIIEF leader in development of low-fission-yield thermonuclear explosives for peaceful applications. In 1965, a VNIIEF-developed nuclear explosive was used to build a water-storage basin on the Chagan river in Kazakhstan. For these works, Slava was awarded the Doctor of Science degree in physics and mathematics in 1968. He continued to work on peaceful applications into the 1970’s and developed innovative applications of nuclear explosives technology.

Slava’s work on ignition of fusion fuel without fissionable materials stimulated his interest in controlled thermonuclear fusion and he recognized that the Disk Explosive Magnetic Generators (DEMG) being developed by his VNIIEF experimental counterpart, Vladimir K. Chernyshev (obituary, Physics Today, vol. 59, pp. 78-79, 2006), could potentially be used to implode a fusion target with an intense magnetic field. A 1979 publication on the topic by Mokhov, Chernyshev, and several others caught the eye of US observers because it displayed a computational capability far exceeding what was thought to be the Soviet capability at the time. Although most US observers doubted the fusion concept (and even doubted that a real V. N. Mokhov existed), a 1988 study by a Los Alamos National Laboratory (LANL) team of R. C. Kirkpatrick, R. S. Thurston, and two of us (IRL, RER) concluded that the concept made physical sense. The DEMG performance reported by the Chernyshev-Mokhov team at the Megagauss-V conference (Novosibirsk, 1989) made the concept very credible.

US scientists did not meet Slava until September 1991, when the Chernyshev-Mokhov team, including one of us (SFG), having recognized through publications and personal contact a common interest with LANL in fusion and pulsed power technology applications, met with one of us (IRL) in Moscow and presented a bold proposal to collaborate with LANL on the VNIIEF fusion concept known as MAGO. The proposal had been signed by VNIIEF’s director and approved by the Russian Ministry of Atomic Energy. However, this was a troubled time in Russia, and the outcome of this meeting could not be predicted, especially its impact on Mokhov and Chernyshev, personally. The possible results ranged from no effect at all to a complete end of the careers of both men.

In fact, the outcome of the meeting led to something far beyond what any of the participants could have dreamed, a formal VNIIEF/LANL collaboration in the area of high-energy-density physics, a collaboration that has conducted more than thirty experimental campaigns and has resulted in more than 300 technical presentations and publications. Much of the present worldwide interest in the fusion approach known as Magnetized Target Fusion (MTF, sometimes referred to as Magneto-Inertial Fusion) can be traced back, at least in part, to joint VNIIEF/LANL publications on joint fusion- related projects.

The international collaboration in the area of high-energy-density physics also renewed Slava’s interest in investigations of EMG performance and using EMGs to study physical properties of materials at high energy densities, topics that were always a focus of his attention. In 1998, he and some of his colleagues were awarded the Russian Federation Government Prize for the development of EMGs and their application for scientific investigations.

Slava’s American colleagues were to learn that his contributions to the Soviet weapons program also lead to him being assigned the house in Sarov that had originally been built for Academician Yuli B. Khariton, the first leader of the Soviet weapons program. The Americans were to spend many evenings at this house, where Slava would always declare “you do not have to drink at my home, but your glasses must always be filled.” Refusal of Slava’s homemade cherry wine was nearly impossible when served along with Slava’s homemade shashlik. The Americans also had many philosophical discussions with Slava in his home office once occupied by Khariton. Slava stated on several occasions that even at the height of the Cold War, many Soviet scientists did not consider the United States to be an enemy but believed that nuclear parity was absolutely essential for world peace.

We believe that Vladislav Mokhov would agree that Prof. Migdal’s advice to “go there” was very fortunate for him and for the world as his talents were especially challenged at VNIIEF. Slava was a prolific scientist, a skilled organizer who was inspired by projects requiring teamwork, and a true patriot. A desire to work for the benefit of mankind and resolve global problems was his most notable characteristic. Colleagues of Vladislav Nikolaevich and numerous people who met him during their life journey will keep his ideas, work, assistance and support in their memory for a long time.