Current projects

Neutrino physics with MINERvA

The MINERvA experiment at the Fermi National Accelerator Center (Fermilab) studies the details of neutrino interactions on nuclei. MINERvA is located underground in the intense NuMI neutrino beam in front of the MINOS near detector. The primary aim of MINERvA is to provide a rich set of neutrino cross section measurments that can be used to improve our understanding and modeling of nuclear effects in neutrino interactions. These data and improved models are being used to reduce systematic errors in neutrino oscillation experiments. MINERvA started taking data in 2010 and is likely to continue taking data until ~2019. The Rochester neutrino group is led by Profs. Bodek, McFarland, and Manly. Past and present members of the group include Aaron Bercellie, Dr. Howard Budd, Tejin Cai, Jesse Chvojka (Ph.D. 2012), Brian Coopersmith, Gonzalo Diaz, Robert Fine, Robert Flight, Alicia Gomez, Jeffrey Kleykamp, Dr. Laura Lioacono, Dr. Aaron McGowan, Chris Marshall, Aaron Mislivec, Jaewon Park (Ph.D. 2013, now at Va. Tech), Dr. Gabe Perdue (now at Fermilab), Dr. Phil Rodrigues, Dr. Dan Ruterbories, Mehreen Sultana, Jeremy Wolcott (Ph.D. 2015, now at Tufts U.)

Neutrino physics with T2K

T2K stands for "Tokai to Kamiokande". This is an experiment that detects neutrinos created in a beam at J-PARC Laboratory in Tokai, Japan (on the eastern coast of Japan, about midway between Tokyo and Fukishima). An intense neutrino beam is sent through a detector sited in Tokai and then travels 295 km to the Super-Kamiokande detector, which is a 50-kiloton water cerenkov detector a mile underground in the mountains of western Japan. T2K measures the probability that neutrinos of one type (say muon neutrinos) oscillate to a different type of neutrino (such as an electron neutrino) as they propagate from Tokai to Kamiokande. Precise measurements of these probabilities may lead to a deeper understanding of the orgin of the matter in our universe. T2K was awarded a share of the 2016 Breakthrough Prize in Fundamenal Physics. The Rochester T2K group is led by Kevin McFarland and SM. Current and previous members of the Rochester T2K group include Dr. Howard Budd, Dr. Phil Rodrigues, Dr. Melanie Day (Ph.D. 2012, now at Wisconsin), Aaron Bercellie, and Konosuke Iwamoto.

Neutrino physics with DUNE

Much of the Rochester neutrino group (Manly, McFarland) is part of the DUNE neutrino experiment. In this experiment an intense neutrino beam will be sent from Fermilab(near Chicago) over 800 miles to a detector sited a mile underground in the Sanford Underground Research Facilty at the northern edge of the Black Hills in South Dakota. The detector in South Dakota will consist of four huge liquid argon time projection chambers filled with over 40 kilotons of liquid argon. The primary part of the physics program will be to make precise measurements of neutrino oscillation parameters. Among other things this may show whether or not CP violation exists in the lepton sector. If so, this deeper understanding of neutrinos may hold the key to understanding the fact that our universe has an excess of matter (that stuff that became the stars and planets and people and dogs) rather than antimatter or essentially no matter. This experiment will also be sensitive to neutrinos from supernovae and search for proton decay. Currently, the Rochester group is heavily involved in the engineering design of the prototype of the large, liquid argon DUNE far detectors which is being constructed and will take data in a beam at the CERN Laboratory near Geneva, Switzerland.

eA scattering with CLAS for neutrinos

Electrons and neutrinos are fairly similar as things go in the particle world. Neither particle interacts via the strong nuclear force. Both particles interact via the weak nuclear force. The main difference between the two particles is that electrons have an electric charge and can interact via the electromagnetic force, whereas neutrinos do not. Historically, electron beams have been used to probe the structure of nucleons and nuclei. They offer a level of control over the initial state and intensity that is very useful for experiments. Modern, intense neutrino beams provide a complementary probe of nuclear and nucleon structure. In the current neutrino physics program, nuclear effects during and after the neutrino interaction on a nucleon inside a nucleus are a significant source of uncertainty. SM and Hyup Woo Lee are studying electron scattering data on different nuclei to measure some of those nuclear effects and provide a constraint on the modeling of those effects, hopefully contributing to a lessening of the systematic errors on neutrino oscillation parameter measurements. Specifically, we are making differential cross section measurments of single charged pion production from 5 GeV electrons scattering off deuterium, carbon, iron, and lead targets using data from the eg2 experiment using the CLAS detector at Jefferson National Laboratory.

Variable time dependent nuclear decay

Interesting periodic changes in long-term studies of nuclear decay rates have been reported. Some ludicrous claims have been made about these results. It is very likely that the obvserved variations are due to seasonal systematic effects. Is that true of all the measurments? Not clear. It's something fun to think about.

Past projects
Heavy ion physics with PHOBOS

PHOBOS was one of four experiments that took data in the early years of operation of the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. RHIC was a major step forward in the field of ultrarelativistic heavy ion physics. The aim of this field is to study the nature of matter at an extremely high energy density, not so different from what may have been present in the first microsecond after the big bang. PHOBOS took data from June 2000 to June 2005. Our group included SM and Dr. Inkyu Park (now at Seoul University). Joshua Hamblen (now at UTenn, Chattanooga) and Peter Walters (now in NYC) got Ph.D.'s with our group working on PHOBOS. We collaborated closely Prof. Wolfs and his PHOBOS group at Rochester, as well as PHOBOS research groups at a number of other places. Our group's main work on PHOBOS was the study of collective flow, i.e. the study of patterns in the transverse production of particles.

e+e- collisions at the Z with SLD

The Stanford Large Detector (SLD) experiment at the Stanford Linear Accelerator Center (SLAC) ran at the collision point of the Stanford Linear Collider (SLC) between 1992 and 1998. The SLC created collisions of electrons and positrons at a center-of-mass energy of 91 GeV, at the peak of the Z boson resonance. SLD, along with the MARK II experiment at SLAC and four large experiments at CERN, made detailed studies of the decay of the Z particle. SLD made substantial contributions to our knowledge of electroweak, heavy quark, and QCD physics. The experiment made the single most precise measurement of the electroweak mixing angle. A review of highlights of the SLD physics program can be found here.

Neutrino Physics with E53 at Fermilab

SM's Ph.D. thesis work involved the analysis of a large data set collected in a wideband neutrino beam at Fermi National Accelerator Center (Fermilab). The data was recorded by the 15-foot bubble chamber filled with a helium-neon mix. For his thesis project, SM compared the then-largest (by a factor of 10) identified electron neutrino sample to a sample of muon neutrino interactions. The work was the best test of neutrino universality made at that time.

Gravitational effects in optical fibers

SM and then graduate student Eric Page (Ph.D. 2001) evaluated the possibility of using the interplay of the gravitationally-induced frequency shift of light along with dispersion in optical fibers to make a very high precision measurment of the gravitational redsfhit of light as a route to test the theory of general relativity. This work formed the basis for Eric Page's Ph.D. and was published in Physical Review D. Get your copy of the paper here!

The primary source of support for most of the research shown on this page is the U.S. Department of Energy Office of Science.