Office Location: 281 Physics
Office Phone: 919-660-2563
Email Address: kotwal@phy.duke.edu
Web Page: http://www.phy.duke.edu/~kotwal
Specialties:
Experimental high energy physics
Research Categories: Experimental High Energy Physics
Research Description:
Prof. Ashutosh Kotwal's research focusses on the physics of fundamental particles and forces at high energies. One of the outstanding mysteries is the mechanism by which particles acquire mass. The theory of gauge symmetry has been very successful in describing the known fundamental forces; however this theory is obviously incomplete because it requires all particles to be massless. Clearly we are missing a big piece of the puzzle. Prof. Kotwal is pursuing this question experimentally using two approaches - precision measurements of fundamental parameters, and direct searches for new particles and forces.
Prof. Kotwal leads the effort to measure very precisely the mass of the W boson, which is sensitive to the quantum mechanical effects of new particles or forces. Using the data from the CDF experiment, he has developed new experimental techniques for performing precise calibrations. He has published measurements of the W boson mass with increasing precision, most recently achieving a precision of 0.06%. He now leads the effort to improve on this precision by a factor of two, which will provide a stringent test of the standard model of particle physics. Prof. Kotwal and his post-doc Bodhitha Jayatilaka and collaborators have also recently published the most precise measurements of the top quark mass in the dilepton channel.
Prof. Kotwal also works with his students, post-doc and collaborators on searches of rare, exotic signatures of new interactions. He has published searches for charged and neutral gauge bosons mediating new weak forces, the Higgs boson in the standard model and in theories that extend the standard model, and excited states of standard model fermions. These particles are predicted in theories where the weak interaction has both left-handed and right-handed couplings (as is indicated by recent data on neutrino oscillations), in supersymmetric theories which impose a fermion-boson duality, and in grand unified theories. He is now pursuing improved techniques to search for the standard model Higgs boson.
Prof. Kotwal's research program spans both the CDF experiment at Fermilab and the ATLAS experiment at the LHC. Prof. Kotwal is performing detailed studies of the silicon and transition radiation trackers of the ATLAS detector. His students on ATLAS are working on searches for new particles and microscopic black holes decaying to top quarks as well as direct searches for Higgs bosons. He wrote the first ATLAS paper on searches for heavy resonances decaying to leptons and continues to lead this effort.
In addition to his experimental research, Prof. Kotwal has done theoretical work in the phenomenology of black holes in extra spatial dimensions. Extra spatial dimensions have been motivated by string theory and to explain why the gravitational force is so much weaker than the electromagnetic force at large distances. In this scenario it is possible for the gravitational force to be strong in the high energy regime of particle colliders, leading to the production of black holes. Prof. Kotwal has published a theoretical analysis of the production and decay of rotating black holes and their experimental signatures. Prof. Kotwal has also co-authored a paper on black hole relics.
Dr. Kotwal is the recipient of the Outstanding Junior Investigator Award and the Alfred P. Sloan Foundation Fellowship. He is a Fellow of the American Physical Society. He has served as project leader for analysis, software and computing on the CDF experiment, and now heads the experimental particle physics research group at Duke.
Teaching (Spring 2012):
Recent Publications (More Publications)