1. Finn Larson


    from UK College of Arts & Sciences Added 3 0 0

    Finn Larson presenting at Great Lakes String 2013

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    • Ufek Aydemir


      from UK College of Arts & Sciences Added 0 0 0

      Ufek Aydemir presenting at Great Lakes String 2013

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      • Sergei Khlebnikov


        from UK College of Arts & Sciences Added 5 0 0

        Sergei Khlebnikov presenting at Great Lakes String 2013

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        • Alex Buchel


          from UK College of Arts & Sciences Added 5 0 0

          Alex Buchel presenting at Great Lakes String 2013

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          • TITLE


            from UK College of Arts & Sciences Added 10 0 0

            Dr. Geoff Greene University of Tennessee, Knoxville While neutrons within nuclei may be stable, the free neutron is unstable against beta decay and has a mean lifetime of ~15min. Free neutron beta decay is, perhaps, the simplest weak nuclear process as it is uncomplicated by many body effects that are present in the decay of nuclei. As a result, it can be directly understood in terms of rather simple fundamental weak interaction theory. Additionally, because free neutron decay is the "prototype" for all nuclear beta decays, the neutron lifetime is a fundamental parameter whose value is important not only in nuclear physics, but also in astrophysics, cosmology, and particle physics. I will give an introduction to the theory of weak nuclear decay and briefly discuss the importance of the neutron lifetime as a parameter in the Big Bang. A review of the experimental strategies for the measurement of the neutron lifetime will be given as well as a discussion of the puzzling discrepancy among the measurements with the lowest quoted uncertainty. Finally, I present a very new result recently obtained at the NIST Cold Neutron Research Facility in Gaithersburg Md.

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            • Dam Son


              from UK College of Arts & Sciences Added 8 0 0

              Dam Son presenting at Great Lakes String 2013

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              • K Narayan


                from UK College of Arts & Sciences Added 8 0 0

                K. Narayan presenting at Great Lakes Strings 2013.

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                • Galaxy Build-up at Cosmic Dawn: New Insights from Ultra-Deep Hubble and Spitzer Observations


                  from UK College of Arts & Sciences Added 25 0 0

                  Dr. Pascal Oesch Space Telescope Science Institute Thanks to ultra-deep observations with the WFC3/IR camera on Hubble the frontier of galaxies has recently been pushed out to z~9-12, only ~450 Myr from the Big Bang. From several large Hubble programs such as the HUDF09, CANDELS, or CLASH, we were able to identify large samples of more than 200 galaxies at z~7-8, and we are now starting to build up the sample sizes of z~9-11 galaxy candidates. In particular, the recent HUDF12 campaign further increased the depth of the WFC3/IR dataset over the Hubble Ultra-Deep Field (HUDF), and enabled us to detect a sample of nine very faint z>8 galaxy candidates in the HUDF. Additionally, the newly completed CANDELS data over GOODS-North now revealed four relatively bright z~9-10 sources, which are in tension with the previous UV LF determination from the GOODS-South field, indicating that star-formation in the early universe might have been very stochastic. Using all z>8 candidates in and around both GOODS fields, we infer that the cosmic star-formation rate density in galaxies with SFR>0.7Msol/yr decreases rapidly at z>8, dropping by an order of magnitude from z~8 to z~10. With complementing, ultra-deep Spitzer IRAC data, we are additionally able to infer the stellar mass densities out to z~8-10. In this talk I will highlight recent progress in exploring the high redshift frontier and in understanding the growth of galaxies in the first two billion years. In particular, I will present current constraints on the UV luminosity function of galaxies at z>8, and I will demonstrate the power of combining deep Hubble and Spitzer data to directly track the star-formation and mass build-up of z>=4 galaxies.

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                  • Higgs Discovery: Implications for Particle Physics - 2 Nov. 2012


                    from UK College of Arts & Sciences Added 55 0 0

                    The LHC has recently discovered a Higgs-like resonance with a mass of about 125 GeV. It may be the missing element of the so-called Standard Model of particle physics. This model was proposed a few decades ago, and, after the inclusion of neutrino masses, describes in an accurate way all measured observables not involving gravity. We shall discuss what are the possible implications of the Higgs Discovery for particle physics and, in particular, for theoretical and experimental physics High Energy Physics in the coming years.

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                    • Picking Up Pieces of the Puzzle


                      from Penn Arts & Sciences Added 14 0 0

                      Cosmologist Mark Devlin builds a telescope that floats to the edge of space.

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