Microlensing Event MOA-2007-BLG-400: Exhuming the Buried Signature of a Cool, Jovian-Mass PlanetWe report the detection of the cool, Jovian-mass planet MOA-2007-BLG-400Lb. The planet was detected in a high-magnification microlensing event (with peak magnification Amax = 628) in which the…Subo Dong, I. A. Bond, A. Gould et al.·Sep 18, 2008SaveLearn
Chemical evolution with radial mixingModels of the chemical evolution of our Galaxy are extended to include radial migration of stars and flow of gas through the disc. The models track the production of both iron and alpha elements. A…Ralph Schoenrich, James Binney·Sep 17, 2008SaveLearn
Forecasting the Dark Energy Measurement with Baryon Acoustic Oscillations: Prospects for the LAMOST surveysThe Large Area Multi-Object Spectroscopic Telescope (LAMOST) is a dedicated spectroscopic survey telescope being built in China, with an effective aperture of 4 meters and equiped with 4000 fibers.…Xin Wang, Xuelei Chen, Zheng Zheng et al.·Sep 17, 2008SaveLearn
Binary frequency of very young brown dwarfs at separations smaller than 3 AUSearches for companions of brown dwarfs by direct imaging mainly probe orbital separations > 3-10 AU. On the other hand, previous radial velocity surveys of brown dwarfs are mainly sensitive to…V. Joergens·Sep 17, 2008SaveLearn
Observation of Pulsed Gamma-rays Above 25 GeV from the Crab Pulsar with MAGICOne fundamental question about pulsars concerns the mechanism of their pulsed electromagnetic emission. Measuring the high-end region of a pulsar's spectrum would shed light on this question. By…The MAGIC Collaboration, E. Aliu·Sep 17, 2008SaveLearn
Curvature Spectra and Nongaussianities in the Roulette Inflation ModelUsing the gradient expansion method of Rigopoulos, Shellard and van Tent which treats cosmological perturbations as gradients on top of a homogeneous and isotropic FRW background, we study the…Aaron C. Vincent, James M. Cline·Sep 17, 2008SaveLearn
A sharp look at the gravitationally lensed quasar SDSS J0806+2006 with Laser Guide Star Adaptive OpticsWe present the first VLT near-IR observations of a gravitationally lensed quasar, using adaptive optics and laser guide star. These observations can be considered as a test bench for future…D. Sluse, F. Courbin, A. Eigenbrod et al.·Sep 17, 2008SaveLearn
Effects of mirror dark matter on neutron starsIf dark matter is made of mirror baryons, they are present in all gravitationally bound structures. Here we investigate some effects of mirror dark matter on neutron stars and discuss possible…Fredrik Sandin, Paolo Ciarcelluti·Sep 17, 2008SaveLearn
Astrophysical Tests of Lorentz and CPT Violation with PhotonsA general framework for tests of Lorentz invariance with electromagnetic waves is presented, allowing for operators of arbitrary mass dimension. Signatures of Lorentz violations include vacuum…Alan Kostelecky, Matthew Mewes·Sep 17, 2008SaveLearn
Cosmological constraints on general, single field inflationInflation is now an accepted paradigm in standard cosmology, with its predictions consistent with observations of the cosmic microwave background. It lacks, however, a firm physical theory, with many…Nishant Agarwal, Rachel Bean·Sep 17, 2008SaveLearn
A Simple Model for Solar Isorotational ContoursThe solar convective zone, or SCZ, is nearly adiabatic and marginally convectively unstable. But the SCZ is also in a state of differential rotation, and its dynamical stability properties are those…Steven Balbus·Sep 17, 2008SaveLearn
Cosmology With Non-Minimally Coupled K-FieldWe consider non-minimally coupled (with gravity) scalar field with non-canonical kinetic energy. The form of the kinetic term is of Dirac-Born-Infeld (DBI) form.We study the early evolution of the…A. A. Sen, N. Chandrachani Devi·Sep 17, 2008SaveLearn
Observing Strategies for the NICI Campaign to Directly Image Extrasolar PlanetsWe discuss observing strategy for the Near Infrared Coronagraphic Imager (NICI) on the 8-m Gemini South telescope. NICI combines a number of techniques to attenuate starlight and suppress…Beth Biller, Etienne Artigau, Zahed Wahhaj et al.·Sep 17, 2008SaveLearn
Performance of the Near-infrared coronagraphic imager on Gemini-SouthWe present the coronagraphic and adaptive optics performance of the Gemini-South Near-Infrared Coronagraphic Imager (NICI). NICI includes a dual-channel imager for simultaneous spectral difference…Mark Chun, Doug Toomey, Zahed Wahhaj et al.·Sep 17, 2008SaveLearn
NICI: combining coronagraphy, ADI, and SDIThe Near-Infrared Coronagraphic Imager (NICI) is a high-contrast AO imager at the Gemini South telescope. The camera includes a coronagraphic mask and dual channel imaging for Spectral Differential…Etienne Artigau, Beth A. Biller, Zahed Wahhaj et al.·Sep 17, 2008SaveLearn
The Brown Dwarf Kinematics Project (BDKP) I. Proper Motions and Tangential Velocities for a Large Sample of Late-type M, L and T DwarfsWe report proper motion measurements for 427 late-type M, L and T dwarfs, 332 of which have been measured for the first time. Combining these new proper motions with previously published measurements…Jacqueline K. Faherty, Adam J. Burgasser, Kelle L. Cruz et al.·Sep 17, 2008SaveLearn
Disk Dominated States of 4U 1957+11: Chandra, XMM, and RXTE Observations of Ostensibly the Most Rapidly Spinning Galactic Black HoleWe present simultaneous Chandra-HETG and RXTE observations of a moderate flux `soft state' of the black hole candidate 4U1957+11. These spectra, having a minimally discernible hard X-ray excess,…Michael A. Nowak, Adrienne Juett, Jeroen Homan et al.·Sep 17, 2008SaveLearn
Are the red halos of galaxies made of low-mass stars? Constraints from subdwarf star counts in the Milky Way haloSurface photometry detections of red and exceedingly faint halos around galaxies have resurrected the old question of whether some non-negligible fraction of the missing baryons of the Universe could…E. Zackrisson, C. Flynn·Sep 17, 2008SaveLearn
Weak localization of electromagnetic waves and radar polarimetry of Saturn's ringsWe use a state-of-the-art physics-based model of electromagnetic scattering to analyze average circular polarization ratios measured for the A and B rings of Saturn at a wavelength of 12.6 cm. This…Michael I. Mishchenko, Janna M. Dlugach·Sep 17, 2008SaveLearn
Microlensing to probe the quasar structure: spectrophotometry of Q2237+0305 and of J1131-1231We present the main results of the first long-term spectrophotometric monitoring of the ``Einstein cross'' Q2237+0305 and of the single-epoch spectra of the lensed quasar J1131-1231. From…D. Sluse, A. Eigenbrod, F. Courbin et al.·Sep 17, 2008SaveLearn
Log-Poisson Hierarchical Clustering of Cosmic Neutral Hydrogen and Ly-alpha Transmitted Flux of QSO Absorption Spectrumwe study, in this paper, the non-Gaussian features of the mass density field of neutral hydrogen fluid and the Ly-alpha transmitted flux of QSO absorption spectrum from the point-of-view of…Yi Lu, Yao-Quan Chu, Li-Zhi Fang·Sep 17, 2008SaveLearn
Diagnosing space telescope misalignment and jitter using stellar imagesAccurate knowledge of the telescope's point spread function (PSF) is essential for the weak gravitational lensing measurements that hold great promise for cosmological constraints. For space…Zhaoming Ma, Gary Bernstein, Alan Weinstein et al.·Sep 17, 2008SaveLearn
Extremely metal-poor stars from the SDSSWe give a progress report about the activities within the CIFIST Team related to the search for extremely metal-poor stars in the Sloan Digital Sky Survey's spectroscopic catalog. So far the…H. -G. Ludwig, P. Bonifacio, E. Caffau et al.·Sep 17, 2008SaveLearn
Large-amplitude intraday variability in QSO 1156+295 observed during a VLBI experimentWe present here the discovery of rapid, large amplitude intraday variability in the compact flat-spectrum radio quasar 1156+295. The detection of 40% flux density variations at 15 GHz on a timescale…T. Savolainen, Y. Y. Kovalev·Sep 17, 2008SaveLearn
Radiation-hydrodynamics simulations of surface convection in low-mass stars: connections to stellar structure and asteroseismologyRadiation-hydrodynamical simulations of surface convection in low-mass stars can be exploited to derive estimates of i) the efficiency of the convective energy transport in the stellar surface…Hans-G. Ludwig, Elisabetta Caffau, Arunas Kucinskas·Sep 17, 2008SaveLearn