Day 340

Monday.

1211.5140
Extended hot halos around isolated galaxies observed in the ROSAT All-sky survey
Anderson, Bregman, Dai

Stack 2k galaxies from the 2MASS very isolated galaxy catalog (2MVIG), as well as subsets of this sample based on galaxy morphology and K-band luminosity.  Detect X-ray emission at ~10 sigma for each subsample; average L_X within 50 kpc is 1e40 erg/s, although the early-type galaxies are more than twice as luminous as the late-type galaxies.  Use spatial analysis to find evidence for extended emission in 5 of the 7 subsamples (full, luminous, early-type, luminous late-type and luminous early-type).  About 1/2 of the total emission is extended, and about 1/3 of the extended emission comes from hot gas.  The average of hot gas mass is 4e9Msun in luminous galaxies, within 50 kpc, and the implied accretion rate is 0.4 Msun/yr.

1211.5146
The BOSS lyman-alpha forest sample from SDSS data release 9
Lee (KG), Bailey, et al

BOSS Lya from 54k quasar spectra with z_qso>2.15 suitable for Lya forest analysis.  This data set probes the IGM with absorption at 2.0<z<5.7 over an area of 3275 sq deg, and encompasses an approximate comoving voume of 20 (Gpc/h)^3.  Each spectrum flagged for bad pixels; correction for known biases in the pipeline estimated noise, masks for cores of damped Lya systems and corrections for their wings, and estimates of the unabsorbed continua so that the observed flux can be converted to a fractional transmission.  The continua are derived using a principal component fit to the quasar spectrum redwards of restframe Lya extrapolated into the forest region and normalized by a linear function to fit the expected evolution of the Lya forest mean-flux.  Estimated continuum errors are ~5% rms.  Discuss possible systematics arising from uncertain spectrophotometry and artifacts in the flux calibration; global corrections for the latter are provided.  Sample provides a convenient starting point for users to analyze clustering in BOSS Lya forest data; fiducial dataset that can be used to compare results from different analysis of BAO in Lya forest.  Full data available from DR9 website.

1211.5213
A robust measure of cosmic structure beyond the power-spectrum: cosmic filaments and the temperature of dark matter
Obreschkow et al

Use DM distribution phase info to get DM particle mass.

1211.5275
Excess ellipticity of hot and cold spots in the WMAP data?
Berntsen, Hansen

The ellipticity of hot and cold spots are perfectly consistent with simulated CMB maps based on concordance cosmology [seems like detector systematics would come into this?], unlike in the WMAP3 analysis.  

1211.5377
Gravitational waves and stalled satellites from massive galaxy mergers at z<1
McWilliams, Ostriker, Pretorius

Model for merger-driven evolution of the mass function for massive galaxies and their central SMBH at late times. . .. Calculate the stochastic GW signal from the resulting BH-binary mergers in the z<1 universe, and find that this population has a signal-to-noise ratio as much as 5x larger than previous estimates.  ...

1211.5589
Probing the bias of radio sources at high redshift
Passmoor ... Hoyle, et al

New methods to probe the bias of intermediate to high-z radio continuum sources for which no z information is available.  Obtain photo-z for matched radio sources from SDSS, then use the publicly available semi-empirical simulation of extragalactic radio continuum sources to infer the z distribution for all FIRST sources, and estimate the z distribution of unmatched sources by subtracting the matched distribution from the distribution of all sources.  Infer that the majority of unmatched sources are at higher redshifts than the optically matched sources and demonstrate how the angular scales of the angular two-point correlation function can be used to probe different z ranges.  Compare the angular clustering of radio sources with that expected for DM and estimate the bias of different samples.