NPAC (Nuclear/Particle/Astro/Cosmo) Forum

Over the years we have accumulated a large number of indications for physics beyond the standard model. This new physics is often sought-after at high masses and energies. However, over recent years it has become increasingly clear that new physics can also appear at low energy, but extremely weak coupling. Experiments and observations at this `low energy frontier' therefore provide a powerful tool to gain insight into fundamental physics, which is complementary to accelerators.

Host: 
Sonny Mantry
Speaker: Joerg Jaeckel Durham University

 

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Room and Building: 
4274 Chamberlin
Host: 
Michael Ramsey-Musolf
Speaker: Sonny Mantry University of Wisconsin at Madison

 

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Room and Building: 
4274 Chamberlin

Gravitational waves are predicted by general theory of relativity to be produced by accelerating mass systems with quadrupole moment. The amplitude of gravitational waves is expected to be very small, so the best chance of their direct detection lies with some of the most energetic events in the universe, such as mergers of two neutron stars or black holes, Supernova explosions, or the Big-Bang itself. I will review the status of current gravitational-wave detectors, such as the Laser Interferometer Gravitational-wave Observatory (LIGO), as well as some of the most recent results obtained using LIGO data. I will also discuss plans and expectations for the future generations of gravitational-wave detectors.

Host: 
Peter Timbie
Speaker: Vuk Mandic University of Minnesota

 

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Room and Building: 
4274 Chamberlin Hall
2 years worth of archival FERMI-LAT data was used to search forgamma-ray
emission from the Andromeda galaxy; the data show no noticeabla gamma-ray image.On-off source aperture photometry using a CO image template shows a 7 sigma excess in the on-source apertures in comparison to the off-source apertures. yielding a flux of (4.95 +/- 0.71`)x10^(-8) photonscm^-2 s^-1 at energies E>100 MeV. The likely origin of this flux will be discussed in terms of the cosmic-ray content and the interstellar gas at Andromeda.
Host: 
Daniel Chung
Speaker: Hakki Ogelman University of Wisconsin at Madison

 

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Room and Building: 
4274 Chamberlin

The effective field theory description yields a systematic treatment of gravitational bound states such as binary systems. Gravitational waves emitted from binaries are one of the prime event candidates at direct detection experiments such as LIGO, VIRGO etc. Due to the multiple scales involved in the binary problem, an effective field theory treatment yields many advantages in perturbative calculations. My talk will review the setup of the effective field theory framework and report on recent progress in gravitational wave phenomenology.

Host: 
Michael Ramsey-Musolf
Speaker: Andreas Ross University of Wisconsin at Madison/Argonne National Laboratory

 

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Room and Building: 
4274 Chamberlin

In this talk I argue that compactified string theories with broken supersymmetry and with stabilized moduli generically have one or more moduli with masses of order the gravitino mass or less. Then cosmological constraints imply the gravitino and moduli masses are of order 30 TeV or heavier, which implies the universe has a non-thermal cosmological history. This in turn suggests that the LSP is wino-like, predicting in particular a signal for galactic positrons and antiprotons consistent with that seen by the PAMELA satellite, and interesting LHC signals. Although the above results hold very generally in string theories, we were led to them from our earlier compactification of M-theory on a G2 manifold, so I will begin the talk with a review of the G2 results.

Host: 
Michael Ramsey-Musolf
Speaker: Gordy Kane U. Michigan

 

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Room and Building: 
5280 Chamberlin Hall

Simulation of a nuclear reactor is extremely important for Double Chooz, an antineutrino experiment whose goal is to extract theta_{13}, and for noninvasive nuclear nonproliferation. An overview of Double Chooz and reactor physics will be given, along with a summary of reactor simulation efforts and code validation. The seminar will conclude with a discussion about the role of simulations in nonproliferation scenarios

Host: 
Stefan Westerhoff
Speaker: Christopher Jones MIT

 

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Room and Building: 
4274 Chamberlin
Cosmic rays with energy greater than about 1020 eV are expected to lose energy through interactions with the cosmic microwave background in what is known as the GZK process. Although the GZK process makes the universe opaque to the highest energy cosmic rays, it also results in the production of neutrinos that can travel nearly unattenuated from even the farthest galaxies. Because neutrinos have no electric charge, their direction of travel is not affected by intergalactic magnetic fields and they can point back to their sources. The Antarctic Impulsive Transient Antenna (ANITA) experiment is designed to detect GZK neutrinos with energy greater than 1018 eV. Antennas hanging from a balloon 35 km over Antarctica search for radio signals from neutrino-induced particle showers in the ice. ANITA did not discover neutrinos in this energy range, and it set a new upper limit on the neutrino flux above 1019 eV. The 2006-2007 flight also detected 16 signals that were consistent with radio emission from air showers above the ice.
Host: 
Peter Timbie
Speaker: Dr. Brian Mercurio The Ohio State University

 

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Room and Building: 
4274 Chamberlin Hall

When a massive star collapses at the end of its life, nearly all of the gravitational binding energy of the resulting remnant is released in the form of neutrinos. I will discuss the nature of the core collapse neutrino burst and what we can learn from its detection. I will cover supernova neutrino detection techniques, and prospects for future supernova-neutrino-sensitive experiments.

Host: 
Albrecht Karle
Speaker: Kate Scholberg Duke University

 

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Room and Building: 
4274 Chamberlin
IceCube's DeepCore is a compact Cherenkov detector located at the bottom-centre of the neutrino observatory. It's purpose is to enhance the sensitivity of IceCube to low neutrino energies (< ~300GeV) and lower the detection threshold of the observatory by an order of magnitude to ~10 GeV. The improved sensitivity in this low-energy window enhances the ability of the observatory to perform dark matter searches via the products of WIMP annihilations, and thus probe an extensive range of the allowable SUSY parameter space for spin-dependent interactions. It also opens new possibilities for atmospheric neutrino oscillation measurements, muon neutrino disappearance and tau neutrino appearance, in an energy region not well tested by previous experiments. Finally, utilizing the IceCube array as an active veto, DeepCore enlarges the field of view of the observatory to the full sky when searching for potential neutrino sources. In this talk I will discuss the current status of the detector, fully deployed as of January 2010, and the development of the DeepCore analyses.
Host: 
Albrecht Karle
Speaker: Darren Grant University of Alberta

 

Available Downloads:

Room and Building: 
4274 Chamberlin

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