Nuclear and Particle Physics Colloquium
Refreshments @ 4:00pm
Jocelyn Monroe, MIT
"Dark Matter Direct Detection: the Road to Discovery"
Brian Odom, University of Chicago
"Dark Matter in Bubble Chambers and Changing Fundamental Constants in Ion Traps"
Bubble chambers can be made stable enough for use in rare event searches. I will discuss recent results from the COUPP collaboration, which has used a bubble chamber to obtain the best sensitivity to spin-dependent coupling between protons and intermediate-mass WIMPs (Weakly Interacting Massive Particles). I will also discuss a proposal to search for time-variation of the electron-proton mass ratio by performing high-precision spectroscopy on trapped molecular ions. Time-dependence of this fundamental "constant" is predicted by several extensions of the standard model.
PAPPALARDO ROOM, 4-349
Ernie Moniz, MIT
"The Energy-Environment Challenge and MIT's Energy Initiative"
Kevin Lesko, LBL
"Deep Underground Science and Engineering Laboratory at Homestake"
NSF has recently sited its efforts to establish The Deep Underground
Science and Engineering Laboratory (DUSEL) at the former Homestake Mine
in Lead South Dakota following a three year examination of possible
sites. I will review the status of the progress and process to
establish DUSEL and highlight the physics experiments we anticipate to
be constructed contemporaneously with the multidisciplinary research
facility. Independently of the NSF DUSEL Process, the State of South
Dakota is pursuing the creation of an interim laboratory, the Sanford
Laboratory, in Homestake. This facility will become operational as
early as next year. I will present these efforts and highlight the
science program that is being prepared for installation in the Sanford
Gilad Perez, Stonybrook
"Top Physics & the Large Hadron Collider (LHC)"
Pavlos Vranas, LLNL
"The Quark and the Supercomputer"
The transition of the quark gluon plasma to stable nuclear matter is
Matthias Burkardt, New Mexico State University
TUESDAY, APRIL 15th - talk begins at 4PM
JOINT ASTRO-LNS COLLOQUIUM - Marlar Lounge, 37-252
Paul Sommers, Penn State
"The astroparticle frontier: recent results from the Pierre Auger Cosmic Ray Observatory"
Arrival directions of the highest energy cosmic rays are correlated with positions of nearby Active Galactic Nuclei. Potential implications may include the following: (1) High energy cosmic rays are accelerated in discrete extragalactic sources. (2) Pion photoproduction causes the observed drop in the cosmic ray energy spectrum near 10 Joules/particle. (3) Intergalactic magnetic fields are not strong, nor are the fields in the halo of our Galaxy. (4) With a bigger collecting area, the Auger Observatory will open a new window of charged particle astronomy. (5) The primary particles are protons, not larger nuclei. (6) Measured properties of the air showers produced by these protons challenge the extrapolation of hadronic interaction models to 300 TeV center-of-mass energy.
TUESDAY, April 29th - talk begins at 4PM
JOINT ASTRO-LNS COLLOQUIUM - Marlar Lounge, 37-252
Gary Steigman, OHIO STATE UNIVERSITY
Bang Nucleosynthesis (BBN) is a key pillar of modern cosmology,
providing a probe of the particle content and expansion rate of the
Universe a mere few minutes after the beginning. The observationally
inferred primordial abundances of Deuterium and Helium-4, when compared
to the BBN predictions, provide an excellent baryometer and
chronometer, respectively. Helium-4 is sensitive to the neutrino
content of the Universe and is a window onto any asymmetry between
neutrinos and antineutrinos and, a probe of the early Universe
expansion rate. On the other hand, the spectrum of temperature
fluctuations imprinted on the Cosmic Microwave Background radiation
(CMB), is sensitive to the baryon density and to the expansion rate
some 400 thousand years later in the evolution of the Universe. The
complementary constraints imposed by BBN and the CMB are reviewed,
revealing a consistent picture of the Universe at two very widely
separated epochs, leading to new, tighter constraints on the baryon
density at present and on possible new physics beyond the standard
models of particle physics and cosmology.
Dima Kharzeev, BNL
"Quantum anomalies and bulk properties of hot QCD matter"
Frank Calaprice, Princeton University
"First Results from the Borexino Solar Neutrino Experiment"
Borexino is a large liquid scintillation detector designed to observe solar neutrinos with energies below 1 MeV. It is located in the Gran Sasso underground laboratory in Italy and has a shielded sensitive mass of 100 ton. The main goal of the experiment is to measure the rate of 0.862 MeV 7Be neutrinos, expected to be ~ 75 events per day without neutrino oscillations. Neutrino oscillations are expected to reduce the rate to about 50% of this value. The detector became operational in May 2007 and first data, published in October 2007, revealed a remarkably low background. The detector has been acquiring data for a year and results based the first full year will be published soon. I will discuss the first results and the potential scientific reach of the experiment, as well as summarize methods developed to overcome the most serious background problems due to natural radioactivity. I will conclude by commenting on other applications of the low background methods that were developed for Borexino.
Gabriella Sciolla (Chair)