Seminar archive 2013

Raw date Event date Title Speakers Host Summary Links
20130916 Sept. 16, 2013, 2:30 pm CDMSlite: A Search for Light WIMPs The CDMS-low-ionization-threshold-experiment was designed to measure low-energy recoils from Weakly Interacting Massive Particles of mass < 10 GeV. This experiment uses voltage-assisted Luke-Neganov amplification of the ionization-energy deposited by particle interactions, which allows us to probe for light WIMP scatters. In this talk I will describe the physics behind CDMSlite and present science results from... More »
20130923 Sept. 23, 2013, 2:30 pm Searching for Satellite Galaxies of the Milky Way in the Dark Energy Survey During the past decade, wide-field optical surveys have brought to light a population of low-luminosity and highly dark-matter-dominated galaxies in the Local Group, which were discovered by their individually resolved stars. These systems have provided new targets to explore the processes which suppress star formation in low-mass dark matter halos, and to constrain the nature... More »
20130930 Sept. 30, 2013, 2:30 pm Dark matter and flavor I will discuss aspects of dark matter that dominantly couples to third generation quarks, including LHC signatures. I will also discuss one realization of a model of “top-flavored” dark matter that arises from supersymmetry with minimal flavor violation. Notes: 1405
20131002 Oct. 2, 2013, 2:30 pm Fermi Bubbles under Dark Matter Scrutiny The quest for Dark Matter signals in the gamma-ray sky is one of the most intriguing and exciting challenges in astrophysics. In this talk I will use Fermi Bubble photon spectrum to study the signal of Dark Matter. By exploring various setups for the full-sky analysis we achieve stable residual gamma ray spectrum, which can... More »
20131007 Oct. 7, 2013, 2:30 pm Applied Astronomy: Optical Studies of Space Debris at Geosynchronous Orbit The majority of artificial objects in Earth orbit are non-functional: inactive satellites, spent rocket boosters, and parts of spacecraft resulting from collisions and fragmentation events. This population of orbital debris is increasing with time, and represents a collision risk to active spacecraft. Studying the debris population at geosynchronous orbit (GEO, period = 23h56m) is a... More »
20131014 Oct. 14, 2013, 2:30 pm Constraining Dark Matter Models using Fermi-LAT Gamma Ray Observations of the Galactic Center Using Fermi Large Area Telescope (LAT) gamma ray observations, several independent groups have found excess extended gamma ray emission at the Galactic Center. It has been hypothesized that the excess emission may be due to dark matter. However, there are significant uncertainties in the diffuse Galactic background. We reevaluated the data accounting for the spectral... More »
20131021 Oct. 21, 2013, 2:30 pm Interferometers for Cosmic Microwave Background Polarization Measurements Measurement of B-type cosmic microwave background (CMB) polarization is a major goal in cosmology. Its achievement will require instruments with unprecedented control of systematic errors. I will discuss the development of QUBIC, a CMB polarization experiment combining aspects of classical imaging instruments and interferometers, which is currently under development. I will also present results of... More »
20131028 Oct. 28, 2013, 2:30 pm The Evolution of Galaxy Clustering as a Function of Luminosity and Color I present measurements of the luminosity and color-dependence of galaxy clustering over the past eight billion years in the PRIsm MUlti-object Survey (PRIMUS). I quantify how the scale-dependent clustering amplitude increases with increasing luminosity and redder color, with relatively small errors over large volumes (9 sq. deg. of sky). I find that red galaxies have... More »
20131104 Nov. 4, 2013, 2:30 pm Dark Matter in a Hidden Sector A new force connecting the standard model with a hidden sector can arise naturally in various theories of physics beyond the standard model. In particular, light extra U(1) gauge bosons, so called hidden photons, are a theoretically well motivated candidate and could act as mediator of the interaction with dark matter particles in the hidden... More »
20131111 Nov. 11, 2013, 2:00 pm Cosmic Sound, Near and Far The coupling of baryons and photons by Thomson scattering in the early universe leads to a rich structure in the power spectra of the cosmic microwave background photons and the matter. The study of the former has revolutionized cosmology and allowed precise measurement of a host of important cosmological parameters. The study of the latter... More »
20131118 Nov. 18, 2013, 2:30 pm The South Pole Telescope and the Millimeter Sky The South Pole Telescope along with, the Herschel Space Observatory, and the recently commissioned Atacama Large Millimeter Array (ALMA) have opened a window to the millimeter (mm) sky and revealed a unique and unprecedented view of the Universe. I will present an overview of the rich scientific questions which are currently being addressed by studying... More »
20131121 Nov. 21, 2013, 12:00 pm Inflationary Models after Planck An unprecedented opportunity to constrain the inflationary theory is provided by the current flow of high accuracy astrophysical data, among which are the Cosmic Microwave Background measurements by the Planck satellite. This is however a challenging project given the size of the inflationary landscape which contains hundreds of different scenarios. In this talk I will... More »
20131125 Nov. 25, 2013, 2:30 pm Challenges of Relic Neutrino Detection and the Status of the PTOLEMY Experiment A new experiment called PTOLEMY (Princeton Tritium Observatory for Light, Early-Universe, Massive-Neutrino Yield) is under development at the Princeton Plasma Physics Laboratory with the goal of challenging one of the most fundamental predictions of the Big Bang – the present-day existence of relic neutrinos produced less than one second after the Big Bang. With the... More »
20131202 Dec. 2, 2013, 2:30 pm The Quest for Primordial Non-Gaussianity Vanilla single-field, slow-roll inflationary theory predicts that primordial fluctuations in the universe were nearly Gaussian random, although some very well-motivated models specifically predict observably large non-Gaussianity. Measurements of primordial non-Gaussianity therefore represent a rare window into the physics moments after the Big Bang. I first review the history of measurements of non-Gaussianity from the cosmic... More »
20131209 Dec. 9, 2013, 2:30 pm Re-discovering the Radio Transient Sky The Astronomy & Astrophysics Decadal Survey identified time domain astronomy as one of the emerging frontier areas, potentially leading to transformational discoveries. Observations at radio wavelengths have illustrated the potential of the time domain (or “transients”), most notably with the discovery of neutron stars as radio pulsars, a discovery later awarded a Nobel Prize. Since... More »
20131216 Dec. 16, 2013, 2:30 pm News from the low-mass WIMP front I’ll discuss some recent developments in direct searches for dark matter focusing on low-mass WIMPs, including LUX, CoGeNT and COUPP/PICO. Notes: 1357