College of Arts and Sciences

While KamLAND apparently rules out Resonant-Spin-Flavor-Precession (RSFP) as an explanation of the solar neutrino deficit, the solar neutrino fluxes in the Cl and Ga experiments appear to vary with solar rotation. Added to this evidence, summarized here, a power spectrum analysis of the Super-Kamiokande (SK) data reveals significant variation in the flux matching a dominant rotation rate observed in the solar magnetic field in the same time period. Four frequency peaks, all related to this rotation rate, can be explained quantitatively. A recent SK paper reported no time variation of the flux, but showed the same peaks with statistically insignificant sensitivity,

Continue reading… Solar Evidence for Neutrino Transition Magnetic Moments and Sterile Neutrinos – David Caldwell

The Atacama Cosmology Telescope (ACT) is a custom-designed 6-meter microwave telescope employing superconducting bolometer array detectors, which will be located in the Atacama Desert of the Chilean Andes in 2006. It will provide maps of the cosmic microwave background at arcminute resolution and micro-Kelvin sensitivity over a hundred square degrees of sky. I will review the scientific motivation for building this instrument, explain some of the technologies which are necessary, and discuss plans for complementary astronomical observations. We aim to compile a catalog of 1000 galaxy clusters and redshifts, selected by their distortions of the microwave background. ACT will provide insights into a wide range of topics including the primordial spectrum of density fluctuations,

Continue reading… The Atacama Cosmology Telescope Project – Arthur Kosowsky

The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory is currently completing run 5. We discuss some of the remarkable and unexpected results emerging from experiments on Gold-Gold collisions at the ultrarelativistic energies of RHIC as well as results from Deuteron-Gold and Proton-Proton collisions at the same energies. Together, they provide a compelling (if not completely understood) picture of

a) the quark-gluon matter produced at RHIC and, unexpectedly,b) a description of the matter constituting the wavefunction of a high energy hadron as a Color Glass Condensate.

Continue reading… Terrestrial Mini-Bang: Transmuting a Color Glass Condensate into Quark Gluon Plasma at RHIC – Raju Venugopalan

Ten dimensional supersymmetric theories of physics such as superstring theory are at heart just higher dimensional generalizations of the Dirac equation. An enduring problem with these theories is how to reduce the spacetime dimension to the four we live in. I will describe a mechanism for reducing 10 spacetime dimensions to 4 without compactification, based on a generalization of the complex numbers known as the octonions. Applying this mechanism to the 10-dimensional Dirac equation leads to a treatment of both massive and massless particles on an equal footing. The resulting unified description has the correct particle spectrum to describe precisely 3 generations of leptons,

Continue reading… Octonions and Fermions – Corinne A. Manogue

As we learn more about the Milky Way Galaxy, extrasolar planets and the evolution of life on Earth, qualitative discussions of the prerequisites for life in a Galactic context can become more quantitative. We model the evolution of the Milky Way Galaxy to trace the distribution in space and time of four prerequisites for complex life: the presence of a host star, enough heavy elements to form terrestrial planets, sufficient time for biological evolution and an environment free of life-extinguishing supernovae. We identify the Galactic habitable zone (GHZ) as an annular region between 7 and 9 kiloparsecs from the Galactic center that widens with time and is composed of stars that formed between 8 and 4 billion years ago.

Continue reading… Exoplanets, The Galactic Habitable Zone and the Age Distribution of Complex Life in the Milky Way – Charley Lineweaver

The cosmological perturbations induced by primordial magnetic fields and its influence on cosmic microwave background (CMB) radiation will be discussed. In particular, CMB temperature anisotropies, polarization, and temperature-polarization cross correlations, as well as Faraday rotation effect will be presented. The possible observational CMB tests to detect primordial magnetic fields will be discussed.

Continue reading… Cosmological magnetic fields vs. CMB – Tina Kahniashvili

We present measurements of the angular cross-correlation between luminous red galaxies from the Sloan Digital Sky Survey and the cosmic microwave background temperature maps from the Wilkinson Microwave Anisotropy Probe. Looking at a number of redshift slices and CMB bands, we find a statistically significant achromatic positive correlation between these data sets, consistent with the expected signal from the late Integrated Sachs-Wolfe effect. We do not detect any anti-correlation on small angular scales as would be produced by a large Sunyaev-Zel’dovich effect, although we do see evidence for some SZ effect in our highest redshift samples. Assuming the flat universe found by the WMAP survey,

Continue reading… Looking for Dark Energy with the SDSS and WMAP – Ryan Scranton

We are apparently at a unique moment in the history of cosmic ray physics. The origin of Ultra-High Energy Cosmic Rays (UCECR) has persisted as a profound astrophysical mystery for decades. But recently, the two premiere experiments for the detection of UHECR (AGASA and HiRes Fly’s Eye) have reported their best results — the culmination of many years of observations and analysis. These results might have been expected to provide key insight into to a new determination of the origin of cosmic rays, except for one fact: the two experiments, AGASA and HiRes have presented results that apparently contradict each other in several ways.

Continue reading… The Pierre Auger Observatory: A New Era Dawning in for Cosmic Rays – Corbin Covault

TransitionsMy coworkers and I have shown that if the QCD phase transition, at about T=150 MeV, is first order, the bubble nucleation and collisions would produce magnetic effects, which would give polarization correlations of the Cosmic Microwave Background Radiation distinct from those predicted by other theoretical cosmological studies. The Electroweak phase transition at T=Higgs Mass is first order in the minimal supersymmetric model, with the mass of the stop (partner of the top quark) being of the order of the Higgs. Applying this theory we are studying magnetic fields generated during the EW phase transition as seeds for galactic magnetic fields.

Continue reading… Cosmological Observatiions of the QCD and Electroweak Early Universe Phase Transitions – Leonard Kisslinger