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From Seminarcommittee
KICP Friday Seminars 2007-2008
========= Fall Quarter =========
September 28, 2007
Speaker: Grant Wilson (UMass)
Millimeter Wavelength Exploration of Submillimeter Galaxies
Abstract: Submillimeter galaxies, first detected by the SCUBA instrument in 1998, are thought to be host to some of the most prolific bursts of star formation in the early universe. Notoriously difficult detect at mm-wavelengths and even more difficult to follow-up with other facilities, a comprehensive understanding of this population has remained elusive over the past decade. In this talk I will describe an ongoing program to create and exploit new catalogs of SMGs to provide a new accounting of the star formation history of the early universe. Our work is centered on imaging made with the AzTEC mm-wavelength camera on three telescopes: the JCMT, the ASTE telescope, and the future Large Millimeter Telescope (LMT). I will describe a collection of survey results from the JCMT and ASTE telescopes and conclude with the exciting prospects of first light with AzTEC on the LMT in 2009.
October 5, 2007
Speaker: Shirley Ho (Princeton)
Abstract: The Cosmic Microwave Background has been providing us with a wealth of information for cosmology. Here, we are going to present the next frontiers of the CMB: the Integrated Sachs-Wolfe Effect, Weak Lensing of CMB and Kinetic Sunyaev-Zeldovich effect.
In order to understand the gravitational potential of the universe, we make use of the ISW effect and Weak Lensing of CMB via the following datasets: WMAP, 2MASS (only for ISW), SDSS photometric LRGs and Quasars and NVSS. We then combine the results from ISW and Weak Lensing of CMB and explore various models of the Universe using Markov Chain Monte-Carlos. We will present methodologies, discussions of various systematics and results on cosmological parameters using ISW and WL of CMB.
To understand the evolution of electron density of the universe, we utilize the kinetic SZ signature of the CMB alongside with a large-scale momentum field. This method is very promising with the upcoming surveys such as ACT and SPT. We will present our method and prediction for upcoming surveys.
October 12, 2007
Speaker: Mike Kesden (CITA)
Abstract: TBD
October 19, 2007
Speaker: Kai Noeske (UCO/Lick & Harvard/CfA)
Abstract: TBD
October 26, 2007
Speaker: David Rapetti (KIPAC, Stanford)
Abstract: Most of the energy density of the Universe is in the form of dark matter and dark energy, and yet these two components are the most intriguing mysteries in current cosmology. Using two complementary X-ray galaxy clusters studies we present new constraints on the mean matter density of the Universe, dark energy density, normalization of the density fluctuation power spectrum, and dark energy equation of state parameter. First, using Chandra measurements of the X-ray gas mass fraction in 42 hot, X-ray luminous, dynamically relaxed galaxy clusters spanning the redshift range 0.05<z<1.1, and employing standard priors on the Hubble constant and the mean baryon density, we obtain tight constraint on the mean matter density and a detection of the effects of dark energy on the distances to the clusters comparable in significance to recent type Ia supernovae (SNIa) studies. Secondly, using the X-ray luminosity function of the Massive Cluster Survey (MACS) in combination with the local BCS and REFLEX galaxy cluster samples, the mass function predictions of Jenkins et al. (2001), a mass-luminosity relation calibrated using the data of Reiprich and Bohringer (2002), and standard priors on the Hubble constant and mean baryon density, we obtain the first precise determination of the dark energy equation of state from measurements of the growth of cosmic structure in galaxy clusters. Combining our results with independent constraints from cosmic microwave background and SNIa studies removes the need for priors on the Hubble constant and mean baryon density and leads to tighter constraints. Both of our results represent strong, independent evidence for cosmic acceleration.
November 2, 2007
Speaker: Beth Willman (Harvard/CfA)
Abstract: TBD
November 9, 2007
Speaker: Brian Gerke (UC Berkeley/ KIPAC, Stanford)
Abstract: TBD
November 16, 2007
Speaker: Brian O'Shea (LANL)
Abstract: I use the cosmological adaptive mesh refinement code Enzo to do a suite of high-resolution numerical simulations of Population III protostellar clouds in a cosmological context. These calculations examine the formation of primordial protostellar clouds at a range of redshifts and in differing cosmic "neighborhoods." I find that these cores have a wide variety of accretion rates - varying by over two orders of magnitude - which may have significant implications for the IMF of Population III stars. I then simulate supernovae from the inferred stellar mass range and follow the evolution of the ensuing supernova remnant until the deposition of metal-enriched gas in the next generation of halos, which generally occurs ~50 million years after the original supernova. The dense gas in the core of these "child" halos is typically enriched to metallicities of ~10^-3 solar, which is above the "critical metallicity" at which metal line cooling dominates over molecular cooling, and suggests that the stars in these halos will have a significantly lower mass range than their Population III parents. This metal enrichment is a local phenomenon, and the transition of the universe from primordial to metal-enriched gas will be quite extended.
November 30, 2007
Speaker: Katie Mack (Princeton)
Abstract: TBD
========= Winter Quarter =========
January 4, 2008
Speaker: Stefan Hilbert (MPA)
Abstract:
Ray-tracing through the Millennium Simulation
Gravitational lensing is playing an increasingly important role in astrophysics and cosmology. In collaboration with people from MPA and Bonn, I investigate gravitational lensing by carrying out ray-tracing through the Millennium Simulation, one of the largest simulations of cosmic structure formation.
In this talk, I will present results for the statistics of strong lensing. Furthermore, I will talk about our efforts towards realistic simulations of weak galaxy-galaxy lensing and cosmic shear surveys. Finally, I will discuss the potential capabilities of future radio telescopes for imaging the cosmic matter distribution.
January 11, 2008
Speaker: Tony Wong (UIUC)
Abstract: TBD
January 18, 2008
Speaker: Martin Pohl (Iowa State)
Abstract: TBD
January 25, 2008
Speaker: Joe Silk (Oxford)
Abstract: TBD
Febuary 1, 2008
Speaker: Mark Wyman (Perimeter Institute)
Abstract: TBD
Febuary 8, 2008
Speaker: Christian Reichardt (Berkeley)
Host: Dan
Recent Results from ACBAR
Abstract: TBD
Febuary 15, 2008
Speaker: Justin Khoury (Perimiter Institute)
Host: Jeff
Abstract: TBD
Febuary 22, 2008
Speaker: Greg Bryan (Columbia)
Abstract: TBD
Febuary 29, 2008
Speaker: Steven Furlanetto
Host: Brant + Dan
Abstract: TBD
March 7, 2008
Speaker: RESERVED
Abstract: TBD
March 14, 2008
Speaker: Mark Krumholz (Princeton)
Abstract: TBD
========= Spring Quarter =========
April 4, 2008
Speaker: Sunil Golwala (Caltech)
Host: Dan
Abstract: TBD
April 11, 2008
Speaker: Mike Niemack
Abstract: TBD
April 18, 2008
Speaker: CAPMAP TALK
Host: TBD
Abstract: TBD
April 25, 2008
Speaker: Ellen Zweibel (University of Wisconsin, Madison)
Abstract: TBD
May 2, 2008
Speaker: TBD
Abstract: TBD
May 9, 2008
Speaker: TBD-- Jo Dunblkey
Abstract: TBD -- New WMAP results!
Host: Jeff McMahon
May 16, 2008
Speaker: Jenny Greene (Princeton)
Host: Dan+Brant
Abstract: TBD
May 23, 2008
Speaker: Greg Bryan (Columbia)
Abstract: The new X-ray observatories have unleashed an explosion of data about the hot gas in galaxy clusters, in the process overturning cherished theories and posing new puzzles, particularly about the impact of AGN on the thermal state of the cluster gas. I review what can be understood from observations, simple theory and high-resolution numerical simulations, showing that in some areas the latest observational results are in surprisingly good agreement with theory. On the other hand, the impact of cooling and heating on cluster cores and -- to a lesser extent -- on global scaling relations, is still not well understood. This uncertainty is important when using clusters for constraining cosmological parameters and I will talk about some ways to improve both our understanding of AGN feedback, and our cosmological constraints.
May 30, 2008
Speaker: Rick Kessler (Local Speaker)
Abstract: TBD (SDSS Supernova Survey)
June 6, 2008
Speaker: TBD
Abstract: TBD
Host: TBD
