1207.0492
JVLA imaging of 12CO J=1-0 and free-free emission in lensed submillimetre galaxies
Thomson et al
z=2.5-2.9 galaxies with L(IR)=1e11-13 Lsun, compare ISM of LIRGs and ULIRGs at high z. Molecular gas mass in the range 2-40e9 Msun assuming maximal SF efficiency.Indicative of warm SF gas, possibly influenced by central AGN. Estimate SFR of 400-600 Msun/yr.
1207.0500
Testing gravity using large-scale redshift-space distortions
Raccanelli, ..., Dore, .. Percival et al
Compare SDSS DR7 z-space distortion with LCDM+GR, Unified Dark Matter, and normal branch DGP; derive parameterized formula for the growth factor. Estimate of growth rate is potentially degenerate with wide-angle effects.
1207.0502
Characterization of dark-matter-induced anisotropies in the diffuse gamma-ray background
Fornasa, ..., Frenk et al
Fermi-LAT diffuse gamma-ray BG between 1-50 GeV: constraint a possible contribution from DM-induced photons. Calculate angular power spectrum for both decaying and annihilating DM candidates (for emission produced in galactic halo and substructures, and extragalactic (sub) halos). Use Millennium-II and Aquarius for DM distribution (extra-galactic and galactic scale haloes). Theoretical error bands span more than two orders of magnitude, dominated by lack of knowledge of the abundance of low-mass (sub)halos.
1207.0503
Cosmological constraints from a combination of galaxy clustering and lensing -- III. Application to SDSS data
Cacciato, van den Bosch, More, Mo, Yang
Simultaneously constrain cosmology and galaxy bias using measurements of galaxy abundances, galaxy clustering and galaxy-galaxy lensing taken from SDSS. Halo model (non-linear matter field), conditional luminosity function (describes halo occupation statistics as a function of luminosity) used to describe halo-DM connection. Account for residual redshift space distortions and projected gg correlation functions; marginalize over uncertainties in the scale dependence of halo bias and the detailed structure of DM haloes. Constrain Omega_m and sigma_8; adopt WMAP7 priors for n, H0, and Omega_b. Omega_m = 0.278pm0.025, sigma_8=0.763pm0.05. Results robust to uncertainties in the radial number density distribution of satellite galaxies, while allowing for non-Poisson satellite occupation distributions results in a slightly lower value for sigma_8 (0.744pm0.05). Demonstrates that at the use of a realistic and accurate model for galaxy bias, down to the smallest NL scales, leads to results consistent with vanilla LCDM cosmology.
1207.0505
Emergent perspective of gravity and dark energy
Padmanabhan (T.)
* emergent: arising as an effect of complex causes and not analyzable simply as a sum of their effects.
Review: describe evidence which show that gravitational field equations are emergent; novel way of studying cosmology (expansion of universe == emergence of space). Dynamics evolves towards a state of holographic equipartition. Correctly reproduces the standard evolution of a Friedmann universe; existence of early inflationary phase and late time acceleration; link value of Lambda to e-folding.
1207.0506
The Swift BAT perspective on non-thermal emission in HIFLUGCS galaxy clusters
Wik et al
Non-clear (marginally significant) detection of inverse Compton emission from galaxy clusters at hard X-ray energies in 6 clusters. No significant excess emission above thermal model predicted at soft energies.
1207.0508
CMB lensing reconstruction in the presence of diffuse polarized foregrounds
Fantaye, Baccigalupi, Leach, Yadav
Case study of 3-channel balloon-borne CMB observing with 5.25 muK-arcmin, 8' angular resolution at 150 GHz to assess the effect of polarized Galactic dust for contamination of CMB lensing signal. For the assumed dust model, polarization fractions as low as a few percent may lead to a significant dust bias to the lensing convergence power spectrum. Investigate parametric component separation method; find a dust contrast regime in which the accuracy of this method breaks down, and in which external information on the dust frequency scaling is needed. Requirement on the accuracy with which the dust spectral index must be estimated or constrained specified.
1207.0509
Complex gas kinematics in compact, rapidly assembling star-forming galaxies
Amorin et al
High-res spec observations for 6 Green Peas at 0.1<z<0.3, showing complex emission-line profiles of Halpha, NII, SII, consisting of the superposition of different kinematical components of spatial extent of a few kpc: a very broad line emission underlying more than one narrower component. Broad underlying Halpha indicate large expansion velocities (>1000 km/s) and very high luminosities (imprint of SNe outflow?). Narrow Halpha show high intrinsic velocity dispersion, suggesting SF proceeds in an ensemble of several compact and turbulent clumps (relative velocity 500 km/s).
1207.0512
The viscous evolution of white dwarf merger remnants
Schwab, Shen, Quataert, Dan, Rosswog
Merger of 2 WDs creates a differentially rotating remnant which is unstable to MHD instabilities, which can lead to viscous evolution on a time-scale short compared to the thermal evolution of the remnant. Present multi-dimensional hydrodynamic simulations of the evolution of WD merger remnants. Generically find that merger remnants evolve towards spherical states on time-scales of hours, even though a significant fraction of the mass is initially rotationally supported. Viscous evolution unbinds only a very small amount of mass (<1e-5 Msun). Viscous heating causes some of the systems with He WD secondaries to reach conditions of nearly dynamical burning: possible that post-merger viscous phase triggers detonation of He envelope in some WD mergers, potentially producing a type Ia SNe via a double detonation scenario.
1207.0523
The Arecibo Legacy Fast ALFA Survey: the galaxy population detected by ALFALFA
Huang, Haynes, Giovanelli, Brinchmann
HI 21 cm line from ALPHALPHA, and photometry from SDSS and GALEX, investigate the global scaling relations and fundamental planes linking stars and gas for a sample of 9417 common galaxies (alpha.40-SDSS-GALEX sample). 96% of the sample belong to the blue cloud, with average gas fraction f_HI=M_HI/M*~1.5. Transition in SF properties at M*~1e9.5 Msun; dispersion of sSFR and SFE mildly increases with M*. Evolution linked to HI content; below transition mass, SF regulated strongly by HI.
1207.0548
Gravitational microlensing of AGN dusty tori
Stalevski, Jovanovic, Popovic, Baes
IR domain microlensing of AGN dusty tori. Torus modeled as clumpy two-phase medium. Influence of geometrical and physical properties of dusty tori on light curves in the IR domain.
1207.0588
Full bispectra from primordial scalar and tensor perturbations in the most general singel-field inflation model
Gao, Kobayashi, ... et al
Compute the full bispectra (incl. X bispectra) of primordial curvature and tensor perturbations in the most general single-field inflation model whose scalar and gravitational equations of motion are of second order. For CMB T and polarization anisotropies.
1207.0642
Quadruple-peaked spectral line profiles as a tool to constrain gravitational potential of shell galaxies
Ebrova et al
As the title says. Stationary shells resulting from a nearly radial minor merger is expected o give a double-peaked line (los velocity distributions of the shell), but each peak splits into two, giving a quadruple-peaked line profile (due to non-zero phase velocity of the shells). Shell kinematics can become an independent tool to determine the content and distribution of the DM in shell galaxies, up to 100kpc from the center of the host galaxy.
1207.0801
The strongest gravitational lenses: II. Is the large Einstein radius of MACS J0717.5+3745 in conflict with LCDM?
Waizmann, Redlich, Bartelmann
Model the distribution function of the single largest ER in a given cosmological volume and to study which underlying assumptions and effects have the strongest impact on the results. Find: distribution of maximum ER is sensitive to the choice of halo mass function, lens triviality, the inner slope, and mass-concentration relation. System not in tension with LCDM.
[Wed **/49] Jul 4
1206.6889
An HST/WFC3-IR morphological survey of galaxies at z=1.5-3.6: II. the relation between morphology and gas-phase kinematics
Law, Steidel, Shapley, Nagy, Reddy, Erb
Rest-fram optical morphologies and gas-phase kinematics from spectra for 204 SF galaxies at 2<z<3. Spectro and gas-phase kinematics closely linked to morphology: compact galaxies with semi-major axis radii r < 2kpc are substantially more likely than their larger counterparts to exhibit LyA in emission. Outflows traced by blue wing of interstellar absorption line features; outflows of larger galaxies less highly ionized and exhibit larger optical depth at the systemic z (may correspond to a decreasing efficiency of feedback in evacuating gas from the galaxy). No evidence for a correlation between outflow velocity and inclination.
1206.6890
Cosmological constraints from a combination of galaxy clustering and lensing -- I. Theoretical framework
van den Bosch, More, Cacciato, Mo, Yang
Present new method that simultaneously solves for cosmology and galaxy bias on non-linear scales. Use Halo model to describe the NL matter distribution, and CLF to specify HOD statistics. Can predict galaxy luminosity function (given cosmology); 2-pt correlation function of galaxies, and gg lensing signal (function of scale and luminosity). Present the analytical model; test against mocks from high-res N-body sims. Model include scale dependence of halo bias; reproduces the 3d gg correlation and galaxy-matter cross-correlation with accuracy better than 10% (in most cases 5%). Ignoring scale dependence and halo exclusion effects causes >40% errors at 1 Mpc/h scales, where the data is most accurate. Projected correlation functions still affected by residual redshift space distortions; ignoring them causes >20% error on large scales. Correct RRSDs to an accuracy of 2% possible with Kaiser formalism.
1206.6923
The Millennium run observatory: first light
Overzier, ... Bertin, Blaizot, ... White, et al
Developed the MRObs, a theoretical virtual observatory which uses virtual telescopes to 'observe' semi-analytic galaxy formation models based on Millennium Run DM simulations. 40 filters from rest-frame UV to IR for 2 SPS models, 3 IGM absorption models, and 2 cosmologies (WMAP1/7). Galaxy distributions for a large number of mock light cones can be 'observed' using models of major ground- and space-based telescopes. First public release of simulated observations for SDSS, CFHT-LS Wide/Deep, GOODS, ERS, CANDELS, and HUDF, and an online MRObs browser that facilitates exploration of simulated data. Number of example applications.
1206.6947
Ram pressure stripping in elliptical galaxies: I. the impact of the interstellar medium turbulence
Shin, Ruszkowski
Gas in ellpticals is not in perfect hydrostatic equilibrium. SNe, stellar winds, or AGN feedback can perturb ISM. Use hydrosims to investigate effect of subsonic turbulence in hot ISM on ram pressure stripping process in ellpiticals. Galaxies with stronger turbulent ISM produce longer, wider and more smoothly distributed tails of the stripped ISM. Even very weak turbulence can accelerate the gas removal from the galaxy via ram pressure stripping.
1206.6981
Can residuals of the solar system foreground explain low multipole anomalies of the CMB?
Hansen, et al
Investigate the contributions from KBO to the WMAP ILC 7 map. Test KBO de-correlated CMB signal; analyze its validity, and find that incorporation of KBO emission can resolve the quadrupole-octupole alignment and parity asymmetry problems, provided that the KBO signals have a non-cosmoogical dipole modulations associated with the statistical anisotropy of the ILC 7 map. Amplitude of the dipole modulation is in agreement with corresponding amplitudes [?].
1206.6995
Gas accretion as the dominant formation mode in massive galaxies from the GOODS NICMOS survey
Conselice et al
Present indirect evidence for the accretion of gas into massive galaxies (>1e11 Msun at 1.5<z<3) using GOODS NICMOS survey (GNS). Observed SFR vs. amount of stellar and gas mass added due to observed major and minor mergers; calculate evolution of stellar mass. Show: observed gas mass fractions are inconsistent with observed SFH for the same galaxy population; this additional gas mass cannot be accounted for by cold gas delivers through minor and major mergers. To sustain star formation at the observed rates there must be additional methods for increasing the cold gas mass; likeliest method is by accretion from IGM. Calculate average gas mass accretion rate is 83 pm 36 Msun/yr. 2/3 of SF from gas accretion, 1/3 from mergers.
[Mon **/42] Jul 2
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