1207.1721
First measurement of the bulk flow of nearby galaxies using the cosmic microwave background
Lavaux, Afshordi, Hudson
Use kSZ to measure local peculiar velocity from WMAP7. Marginalize over thermal SZ contribution, possible unresolved point source contamination, and galactic foregrounds (dust, synchrotron and free-free emission); report kSZ bulk flow at 90% confidence level. Using <50 Mpc/h galaxies, find kSZ bulk flow of V=533 pm 263 km/s, in the direction consistent with bulk flow measurements on a similar scale (l=324, b=-7). Comparison constrains the ionized baryonic budget in the local universe. Over 500 Mpc/h scales, velocity is 470 km/s (upper limit), inconsistent with bulk flow of clusters from kSZ. Planck will do a better job.
1207.1722
A sampling strategy for high-dimensional spaces applied to free-form gravitational lensing
Lubini, Coles
* polytope: a geometric object with flat sides, which exists in any general number of dimensions (e.g., polygon is a polytope in 2d).
Metropolis-Hastings algorithm designed to efficiently sample general convex prolytopes in 100 or more dimensions. Improves sampling strategies used for free-form reconstruction of gravitational lenses. Parallel implementation within GLASS lens modeling framework. Able to produce uniform uncorrelated random samples necessary for exploring the degeneracies inherent in lens reconstruction.
1207.1723
Semi-analytic galaxy formation in early dark energy cosmologies
Fontanot, Springel, Angulo, Henriques
Study EDE cosmologies on galaxy properties with high-res num sims with SAM of galaxy formation and evolution. EDE produces an earlier growth of structures and a modification of LSS evolution. WIth EDE, more galaxies, corresponding SFH and stellar mass increased at high-z. Modifications from EDE cosmology are of the same order of magnitude as intra-SAM variations for standard LCDM, suggesting that it is difficult to use such predictions alone to distinguish different cosmological scenarios. But with independent info on host DM haloes included, SAM prediction on galaxy bias may provide important clues on the expansion history and EoS evolution.
1207.1736
2FGL J1311.7-3429 joins the black widow club
Romani
* Black Widow pulsar: class of eclipsing binary millisecond pulsars with an ablating companion (destroyed by gravitational environment caused by the neutron star).
As the title says. Shorted orbital period of any known spin-powered pulsar; flares may be magnetic events on the rapidly rotating companion or shocks in the companion stripping wind. A radio-quiet millisecond pulsar; a small subset of the gamma-ray pulsar population.
1207.1739
A Chandra proper motion for PSR J1809-2332
Van Etten, Romani, Ng
Measure a significant proper motion of the pulsar point source over 11 yr baseline. 0.30 pm 0.06" shirt, association with proposed SNR parent.
1207.1750
Ultra deep X-ray survey of the large Magellanic cloud
Grebenev, Lutovinov, Tsygankov, Mereminskiy
INTEGRAL observatory survey, 7Ms, 20 sources, 10 belonging to LMC (7HMXBs, 2 PSRs, 1 LMXB), six of extragalactic origin, and others from local group (MW and SMC). 4 new hard x-ray sources, 2 are AGNs.
1207.1774
Pulse spectral evolution of GRBs: implication as standard candle
Basak, Rao
Demonstrate that E_peak,0 bears a very strong correlation with the isotropic energy of the individual pulses, and hence, each pulse can be used as a luminosity indicator. Find that the peak energy/temperature always decreases exponentially with fluence in the later part of a pulse. Multiple spectral components in they initial rising part provide a comprehensive empirical description of the spectral and timing behavior of prompt GRB pulses. Use GRB as standard candles (spectral parameters as proxy for redshift).
1207.1815
A search for low-mass WIMPs with EDELWEISS-II heat-and-ionization detectors
EDELWEISS Collaboration, et al
Find no evidence for an exponential distribution of low-energy nuclear recoils that could be attributed to WIMP elastic scattering. WIMPs of mass 10 GeV, one event, 90% CL limit of 1e-5 pb on spin-independent WIMP-nucleon scattering cross-section.
1207.1816
AKARI Near-Infrared spectroscopy of luminous infrared galaxies
Lee, Hwang, Lee, Kim, Lee
36 (U)LIRG at z=0.01-0.4, find half of ULIRGs optically classified as non-Seyferts show AGN signatures. Measure contribution of buried AGN to the IR luminosity from SED-fitting to IRAS photometry, about 5-10%, smaller than AGN contribution of ULIRGS including Seyferts (10-40%).
1207.1853
On the anisotropic density distribution on large scales
Papai, Sheth
Derive formula for anisotropic density distribution around haloes and voids on large scales. Assume orientation of NL structures strongly correlated with the Lagrangian shear, and gives a qualitative understanding of enhanced clustering signal along the major axis of haloes. Measured amplitude inconsistent with a model in which the alignment is produced by the initial inertia rather than shear tensor.
1207.1870
Modelling non-dust fluids in cosmology
Christopherson, Hidalgo, Malik
Give relativistic corrections in Newtonian physics for matter with pressure, for dynamics of matter inhomogeneities. Example: scalar field DM model which has non-zero pressure perturbations. Discuss problems which may arise when modeling theory with numerical simulations.
1207.1907
Dust could lightning in extraterrestrial atmospheres
Helling, Jardine, Diver, Witte
Expect thunderstorms in atmospheres of brown dwarfs and giant gas planets with mineral clouds, through ionization by CRs.
1207.1962
Very-high-energy gamma-ray emission from high-redshift blazers
Neronov, Semikoz, Taylor, Vovk
Study the possibility of detecting VHE gamma-ray emission (>100 GeV) from high-z sources (z>0.5). Currently ground-based gamma-ray telescope would be challenging, but possible with proposed high-altitude Cherenkov telesopce 5@5.
1207.2035
Newtonian versus relativistic cosmology
Flender, Schwarz
Show how the relativistic matter and velocity power spectra behave in different gauges. Find that Newtonian theory is wrong on scales > 10 Mpc. [???]
1207.2042
Microlensing of quasar broad emission lines: constraints on broad line region size
Guerras, .. Kochanek, Falco, ... et al
Differential microlensing of broad emission lines between 18 quasar image pairs in 16 gravitational lenses. Find: high ionization lines such as CIV are more strongly micro lensed than low ionization lines, indicating that the high ionization line emission regions are more compact. Estimate broad-line region radius of 24 and 55 light days (with large margin of error) for the high and low ionization lines, respectively. Estimates agree with local reverberation mapping studies. Emission line regions of more luminous quasars are larger.
1207.2044
Short-term variability of 10 trans-Neptunian objects
Thirouin et al
Bias towards objects with small amplitude light curve (usually <0.15mag variation) and second one against objects with log rotational period.
1207.2048
The initial conditions of star formation: cosmic rays as the fundamental regulators
Papadopoulos, Thi
CRs control the thermal, ionization and chemical state of dense H2 gas regions that otherwise remain shielded from far UV and optical stellar radiation; they dramatically alter the initial conditions of SF. In extreme CR dominated region H2 cloud fragmentation will produce far fewer low mass (<8Msun) stars, yielding a top-heavy stellar IMF. Integrated galactic IMF expected to be strong functions of SFH.
1207.2059
Do all stars in the solar neighborhood form in clusters? A cautionary note on the use of the distribution of surface densities
Gieles, Moeckel, Clarke
Bressert et al show surface density distribution of low-mass, young stellar objects in solar neighborhood is approximately lognormal, concluded SF process is hierarchical, only a small fraction of stars form in dense star clusters. Peak and width of density distribution is also what follows if all stars form in bound clusters which are not significantly affected by the presence of gas and expand by two-body relaxation. ... Conclude that degeneracy of YSO surface density distribution complicates its use as diagnostic of the stellar formation environment.
1207.2109
Nonlinear general relativistic corrections to redshift space distortions, gravitational lensing magnification and cosmological distances
Umeh, Clarkson, Maartens
Range of subtle relativistic effects explored theoretically, and offer the potential to probing GR in this new regime. Distance-redshift relation to 2nd order, with magnification and NL z-space distortions. A range of new lensing effects: double--integrated and NL ISW, transfers Doppler effects in z-space distortions, lensing from the induced vector mode and GW BGs, in addition to lensing from the second-order potential. ID a new double-coupling between the density fluctuations integrated along the LoS, and gradients in the density fluctuations coupled to transverse velocities along the LoS. ...
1207.2115
Photometry of the stellar tidal stream in the halo of Messier 63
Chonis et al
Stream originates from the accretion of a 1e8 Msun satellite in the last few Gyr, color consistent with Local Group dwarfs and similar to outer region of M63's disk and stellar halo. Describe possible effects of such an accretion event in the larger picture of the parent galaxy.
1207.2124
Updating quasar bolometric luminosity corrections. II. infrared bolometric corrections
Runnoe, Brotherton, Shang
Present IR corrections from 62 bright quasars of low to moderate-redshift. (0.03<z<1.4). Bolometric luminosities estimated using these corrections are typically smaller than those derived from a few in the literature.
1207.2138
Constructing mock catalogues for the REFLEX II galaxy cluster sample
Balaguera-Anotlinez, Sanchez, Böhringer, Collins
Construct a suite of galaxy cluster mock catalogues from N-body sims, based on cluster abundance measurements from REFLEX II. Requires mass-X-ray luminosity relation deviating fro ma simple power law. Set of mock catalogues provide samples with self-calibrated scaling relations of galaxy clusters. useful tool to explore different systematic effects and statistical methods involved in constraining astrophysical and cosmological info from cluster surveys.
1207.2139
Weak lensing by line-of-sight halos as the origin of flux-ratio anomalies in quadruply lensed QSOs
Inoue, Takahashi
Explore WL effect by LOS haloes and sub halos with M<1e7 Msun in QSO-galaxy SL systems with quadruple images in LCDM universe. Find ratio of magnification perturbation due to intervening haloes to that of a primary lens is typically 10%, and the predicted values agree well with the estimated values for 6 observed QSO-galaxy lens systems with quadruple images in the mid-IR w/o considering the effects of substructures inside a primary lens. Also find estimated amplitudes of convergence perturbation for the 6 lenses increase with the source redshift as predicted by theoretical models. Flux ratio anomalies in QSO-galaxy SL systems offer a unique probe into clustering property of mini-haloes with a mass of M<1e6 stars.
[Tue **/64]
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