More Information about Professor John P. Schiffer

Among the many honors Professor Schiffer has accumulated:

Fellow              APS (1968); AAAS (1984);
                       National Academy of Sciences (1987);
                       American Academy of Arts and Sciences (1998);
                       Royal Danish Academy of Arts and Sciences (1996)

Other              Guggenheim Fellow (1959); Humboldt Award (1973); 
                      Bonner Prize
(APS) (1975); Wilbur Cross Medal (Yale) (1985);
                      Dr. Sc. (hon) University of Notre Dame (1999)

Professor Schiffer is involved with a variety of research endeavors:

My primary interests have been in trying to understand the single-particle structure and effective interactions that underlie the structure of structure of atomic nuclei.  This entails calibrating reaction mechanisms to best extract the relevant information.  Some of this work was done a long time ago – and some recently – particularly with a focus on how these nuclear properties might change as nuclei move further away from stability.

 

An additional interest of mine has been to investigate ‘exotic’ phenomena that are associated with nuclear physics.  Among these (and the only one that turned out to be real) was the Mössbauer effect.  When I first heard of it (a small effect in 191Ir) we were incredulous but then Argonne was were the first to repeat this successfully.  Shortly after this I came across 57Fe, and from this a whole industry emerged; I worked on relativistic red-shift measurements.  After quarks were first proposed by Gell-Mann, I spent a fair amount of effort in looking for stable fractional charges in Nature – including sea water, the atmosphere, meteorites, and moon dust, and on trying to reproduce some positive experiments in this regard – we found none.  After that came the ‘GSI positron lines’ reported from the collisions between very heavy nuclei, and our work with APEX could not confirm the reported phenomena.  I did some work on cold fusion.  Recently the reported ‘triggered decay’ of an isomer in Hf by x-rays, lead to speculations about new method of airplane propulsion and of other uses.  We found no such effect. We also set a limit on helium-like strangelets in nature.

 

I am currently involved with a number of measurements with unstable light nuclei that are of interest both for nuclear structure and related to microscopic ab origine theoretical predictions of nuclear properties and for astrophysical interests.  I have proposed a new scheme for charged-particle detection from reactions in inverse kinematics (that is required with radioactive beams) a technique that could overcome many of the current difficulties encountered in such measurements.  The scheme requires a large super-conducting solenoid and methods of obtaining such a solenoid and detector array are being pursued.

 

There is great interest at present in observing neutrinoless double beta decay (0n2b) in nuclei. If this process is observed, that will be of interest, not only because it would show that neutrinos are their own antiparticles, but because the rate for the process will be a direct measure of the neutrino mass – probably the only handle on this quantity, but only if the nuclear matrix element is known.  Current theoretical predictions for the nuclear matrix elements are spread over almost two orders of magnitude.  I am carrying out a program of measurements to help narrow down the uncertainties in our knowledge of those specific aspects of nuclear structure that are relevant to this rate, especially in the most promising candidate for an early experiment, 76Ge.