Day 758

Monday.

1410.0681
The quenching of the ultra-faint dwarf galaxies in the reionization era
Brown,... Geha, et al

Study SFH of Bootes I, Canes Venatici II, Coma Berenices, Hercules, Leo IV, and Ursa Major I ultra-faint dwarf galaxies, with HST/ACS, DEIMOS medium-res spectroscopy, and updated Victoria-Regina isochrones tailors to the abundance patterns appropriate for these galaxies.  5/6 are best fit by SFH where at least 75% of the stars formed by z~10 (13.3 Gyr ago).  All of the galaxies are consistent with 80% of the stars forming by z~6 (12.8 Ghr ago) and 100% of the stars forming by z~3 (11.6 Gyr ago).  The similarly ancient populations of these galaxies support the hypothesis that SF in the smallest DM sub-haloes was suppressed by a global outside influence, such as the reionization of the universe.

1410.0691
Prospects for delensing the cosmic microwave background for studying inflation
Simar, Hanson, Holder

Present forecasts for how well the gravitational lensing B-modes can be removed, assuming that the lensing potential can be estimated either internally from CMB data, or using maps of the CIB as a tracer.  Find that maps of CIB are more effective for delousing at the noise levels of the current generation of CMB experiments, while the CMB maps themselves will ultimately be best for delousing when the experiments have sufficient sensitivity to measure the tensor spectra index to an accuracy of 0.02 or better.

1410.0714
Inferring host dark matter halo masses of individual galaxies from neighboring galaxy counts
Oguri, Lin

How well can one infer DM halo masses of individual galaxies?  Based on HOD framework, analytically compute the number of neighboring galaxies within a cylinder of some z interval and radius in transverse comoving distance.  The result is used to derive the conditional PDF of the host halo mass of a galaxy, given the neighboring galaxy counts.  Compare analytic results with those obtained using a realistic mock galaxy catalog, finding reasonable agreements.  Find the optimal cylinder radius to be ~0.5-1 Mpc/h for the inference of halo masses.  The PDF is generally broad, and sometimes has two peaks at low- and high-mass regimes, because of the effect of chance projection along the LoS.  Potential applications and extensions of the new theoretical framework developed herein are also discussed.

1410.0734
Galaxy halo masses from weak gravitational lensing
Mandelbaum

Review: GGLensing for galaxy halo mass measurements.  Other tracers: stellar mass or luminosity---find relation between DM halo mass.  Also review some of the factors that can complicate analysis, such as the choice of modeling procedure, and choices made when dividing up samples of lens galaxies.

1410.0791
Resolving the clumpy structure of the outflow winds in the gravitationally lensed quasar SDSS J1029+2623
Misawa, ... Oguri, et al

SL z~2.197 quasar image pair A,B with delay of ~744 days and separation 22".5.  Difference in absorption profiles in A and B unchanged from 2010 to 2013; implying the difference is not due to time variability of the absorption profiles over the time delay, but rather due to difference along the sight lines.  Time variation in C IV absorption in both A and B due to change of ionization condition.  If a typical absorber's size is smaller than its distance from the flux source by more than 5 orders of magnitude, it should be possible to detect sightline variations among images of other smaller separation, galaxy-scale gravitationally lensed quasars.