Astrophysics Seminars

ABSTRACT: Herschel Space Observatory, a 3.5m far-infrared telescope, was launched 14 May 2009, and is now located at the Earth-Sun L2 point, carrying out imaging and spectroscopy at wavelengths from 70um to 500um with LHe-cooled detectors. For...

ABSTRACT: We take a fresh look at high energy radioactive nuclei data reported in the 90's and at the positron data recently reported by PAMELA. Our aim is to study the model independent implications of these data for the propagation time scales of...

ABSTRACT: Core-collapse supernovae are a puzzle that has taxed theorists and computational science for half a century. Such explosions, the source of much of the heavy elements in the Universe and the birthplace of neutron stars and stellar-mass...

ABSTRACT: I briefly review recent Auger results and the likely astrophysical sources responsible, such as gamma-ray bursts, active galactic nuclei, magnetars and hypernoave. I then discuss the secondary GeV-TeV gamma-ray and neutrino signatures of...

ABSTRACT: The cosmic rays (CRs) in star-forming galaxies dominate their emission at gamma-ray and radio wavelengths. The observed linear correlation between the nonthermal radio emission and the thermal infrared emission of galaxies, the far...

ABSTRACT: The discovery of the accelerating expansion of the Universe poses a profound challenge to our understanding of fundamental physics. I will describe our group's ongoing efforts to determine the nature of the Dark Energy, including next...

ABSTRACT: Cosmological hydrogen recombination has recently been the subject of renewed attention because of its importance for predicting the power spectrum of cosmic microwave background anisotropies. Correctly interpreting the upcoming data from...

In the first part of my talk, I discuss how precision measurements are transforming our understanding our universe, and the prospects of dramatically better measurements from mapping neutral hydrogen in a large fraction of our Hubble volume. I then...

ABSTRACT: In this talk I'll review recent results from the Atacama Cosmology Telescope. The results pertain to (1) millimeter galaxy populations, (2) galaxy clusters discovered through the Sunyaev Zel'dovich effect, (3) primary CMB anisotropies...

In applications as varied as the measurement of stellar proper motions, the determination of the Milky Way mass with maser kinematics, and the selection of quasar targets for SDSS-III BOSS, precise---and, more important, accurate---data analysis...