Martin Breidenbach

Professor Emeritus, Particle Physics and Astrophysics
Ph.D., MIT, Physics (1970)
B.S., MIT, Physics (1965)
I have worked for more than 45 years in experimental particle physics, often in developing new kinds of electronics and instruments critical to the detectors that enable the physics experiments of interest. In 1965 through 1971, I was involved in the electron scattering program at SLAC. The deep inelastic experiments that discovered the scaling and point like structure in the nucleon, later interpreted as quarks, was my Ph.D. thesis. I then spent a year at CERN, mostly doing an experiment on minimum bias behavior of proton-proton scattering at the newly operating Intersecting Storage Rings. Despite intentions to stay longer at CERN, I was persuaded by Professor Richter to return to SLAC and join his SPEAR storage ring group. In the 1974 “November Revolution”, we discovered the  and ’ particles, soon interpreted as bound states of charm-anti-charm quarks, which caused essentially complete acceptance of the quark model as real. Another critical discovery at SPEAR was the  lepton, leading to the third family of the Standard Model.

Subsequently Professor Charles Baltay and I were co-spokesmen of the SLD, a comprehensive large detector for the SLAC Linear Collider (SLC), where we did Z physics, particularly polarization asymmetries possible because of the SLC polarized electron beam which led to a (correct) prediction of the Higgs mass, and precision b physics with a 300 MPixel CCD vertex detector.

I am now involved in the design of a detector for the International Linear Collider which may be built in Japan, which has led to substantial involvement in Si detector sensors and associated readout ASIC’s. I believe we have developed the first wafer scale sensors with on sensor traces leading to a relative small area “readout system on a chip” that delivers processed digital signals to a DAQ.

I also work on a search for neutrinoless double beta decay (02) in 136 Xe. The 02 experiment utilizes a liquid xenon TPC requiring ultra-low background materials, techniques, and locations, which was an education into rather different experimental techniques from collider detectors.

I am working on a new concept for an e+e- linear collider called C^3 for the Cool Copper Collider. The Cool Copper Collider (C3) is an advanced concept for a high energy e+e- linear collider. It is based on a new SLAC technology that dramatically improves efficiency and breakdown rate. C3 uses distributed power to each cavity from a common RF manifold and operates at cryogenic temperatures (LN2, ~80K). This makes it robust at high gradient: 120~MeV/m.

C3 is a promising option for a next-generation e+e- collider. It has the potential to reach energies of up to 1 TeV, which would allow it to study the properties of particles that are difficult to access with current experiments. C3 is also relatively affordable, which makes it a more viable option than some of the other proposed linear colliders.

Finally, these recent experiences have led to exploratory collaborative efforts in neuroscience, where we believe our SLAC expertise in sensors and electronics could be rather synergistic with Stanford efforts in tACs and in neural recording probes.