Proton-proton collisions at √ s = 7 TeV and heavy ion collisions at √ s NN = 2.76 TeV were produced by the LHC and recorded using the ATLAS experiment's trigger system in 2010. The LHC is designed with a maximum bunch crossing rate of 40 MHz and the ATLAS trigger system is designed to record approximately 200 of these per second. The trigger system selects events by rapidly identifying signatures of muon, electron, photon, tau lepton, jet, and B meson candidates, as well as using global event signatures, such as missing transverse energy. An overview of the ATLAS trigger system, the evolution of the system during 2010 and the performance of the trigger system components and selections based on the 2010 collision data are shown. A brief outline of plans for the trigger system in 2011 is presented.

These lectures survey the present situation and future prospects in selected areas of particle physics phenomenology: (1) the top quark, (2) the Higgs boson in the Standard Model, (3) strong W W scattering, (4) supersymmetry, (5) the Higgs sector in minimal supersymmetry, (6) low-energy constraints on supersymmetry.

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Published B and V fluxes from nearby Type Ia supernovae are fitted to light-curve templates with 4-6 adjustable parameters. Separately, B magnitudes from the same sample are fitted to a linear dependence on B −V color within a post-maximum time window prescribed by the cmagic method. These fits yield two independent SN magnitude estimates B max and B BV . Their difference varies systematically with decline rate ∆m 15 in a form that is compatible with a bilinear but not a linear dependence; a nonlinear form likely describes the decline-rate dependence of B max itself. A Hubble fit to the average of B max and B BV requires a systematic correction for observed B −V color that can be described by a linear coefficient R = 2.59 ± 0.24, well below the coefficient R B ≈ 4.1 commonly used to characterize the effects of Milky Way dust. At 99.9% confidence the data reject a simple model in which no color correction is required for SNe that are clustered at the blue end of their observed color distribution. After systematic corrections are performed, B max and B BV exhibit mutual rms intrinsic variation equal to 0.074 ± 0.019 mag, of which at least an equal share likely belongs to B BV . SN magnitudes measured using maximum-luminosity or cmagic methods show comparable rms deviations of order ≈0.14 mag from the Hubble line. The same fit also establishes a 95% confidence upper limit of 486 km s −1 on the rms peculiar velocity of nearby SNe relative to the Hubble flow.

We present ultraviolet (UV) spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2004ef, 2005M, and 2005cf) obtained with the UV prism of the Advanced Camera for Surveys on the Hubble Space Telescope. This dataset provides unique spectral time series down to 2000 Å. Significant diversity is seen in the near-maximum-light spectra (∼ 2000-3500 Å) for this small sample. The corresponding photometric data, together with archival data from Swift Ultraviolet/Optical Telescope observations, provide further evidence of increased dispersion in the UV emission with respect to the optical. The peak luminosities measured in the uvw1/F250W filter are found to correlate with the B-band light-curve shape parameter ∆m 15 (B), but with much larger scatter relative to the correlation in the broad-band B band (e.g., ∼ 0.4 mag versus ∼ 0.2 mag for those with 0.8 < ∆m 15 (B) < 1.7 mag). SN 2004dt is found as an outlier of this correlation (at > 3σ), being brighter than normal SNe Ia such as SN 2005cf by ∼ 0.9 mag and ∼ 2.0 mag in the uvw1/F250W and uvm2/F220W filters, respectively. We show that different progenitor metallicity or line-expansion velocities alone cannot explain such a large discrepancy. Viewing-angle effects, such as due to an asymmetric explosion, may have a significant influence on the flux emitted in the UV region. Detailed modeling is needed to disentangle and quantify the above effects.

The Nearby Supernova Factory (SNfactory) is an ambitious project to find and study in detail approximately 300 nearby Type Ia supernovae (SNe Ia) at redshifts 0.03 < z < 0.08. This program will provide an exceptional data set of well-studied SNe in the nearby smooth Hubble flow that can be used as calibration for the current and future programs designed to use SNe to measure the cosmological parameters. The first key ingredient for this program is a reliable supply of Hubble-flow SNe systematically discovered in unprecedented numbers using the same techniques as those used in distant SNe searches. In 2002, 35 SNe were found using our test-bed pipeline for automated SN search and discovery. The pipeline uses images from the asteroid search conducted by the Near Earth Asteroid Tracking group at JPL. Improvements in our subtraction techniques and analysis have allowed us to increase our effective SN discovery rate to ∼12 SNe/month in 2003.