Day 140

Monday.  No more.  Weekend, had lunch with Daniela.  Went to the Adventmarkt with Aaron.  Parents will come visit me over the weekend.


1111.4208
Non-thermal emissions from cool cores heated by cosmic-rays in galaxy clusters
Fujita, Ohira


Non-thermal emissions from CR proton streaming and ICM interaction, stably heating the cores, where CR prevail.  Comparison between model and radio observations show that overall CR spectra must be steep, and most of the CRs in the cores are low-energy CRs.  This indicates that the (AGN) shocks which produce CR travel in the hot ICM with fairly small Mach numbers.  Synchrotron emissions from secondary electrons should be observed as radio mini-halos in the cores (at low frequencies).  The steepness of the spectra makes it difficult to detect non-thermal X-ray and gamma-ray emissions from the cores.  The low-energy CRs may be heating optical filaments observed in the cores.


1111.4209
Observing turbulent fragmentation in simulations: predictions for CARMA and ALMA
Offner, Capodilupo, Schnee, Goodman


Synthetic observations of starless and protostellar cores undergoing fragmentation on scales of a few thousand AU to produce wide binary systems.


1111.4211
The spatial and velocity bias of linear density peaks and proto-haloes in the LCDM cosmology
Elia, Ludlow, Porciani


Lagrangian bias of CDM haloes within LCDM cosmology.  Analysis of proto-halos--the initial conditions with the subset of particles belonging to individual redshift-zero haloes.  Measure number density, velocity divergence fields, estimate auto spectral densities, measure cross spectral densities with linear matter distribution.  Test Lagrangian-bias model presented by Desjacques and Sheth---based on the assumption that haloes form out of local density maxima of a specific height.  Comparison validates the predicted functional form for the scale-dependence of the bias for both the density and velocity fields.  Also show that the bias coefficients are accurately predicted for the velocity divergence.  But the theoretical values for the density bias parameters do not match the numerical results as a function of halo mass.  Likely due to simplistic assumptions that relate virialized haloes to density peaks of a given height in the model.  Detect appreciable stochasticity for the Lagrangian density bias, even on very large scales; corresponds to higher order corrections.


1111.4212
Clustering of sub-millimeter galaxies in a self-regulated baryon collapse model
Xia, Negrello, Lapi, Zotti, Danese, Viel


CIB anisotropies in the framework of the physical evolutionary model for proto-spheroidal galaxies.  2 parameter fitting: minimum halo mass and power-law index of the mean occupation function of satellite galaxies.  Effective halo mass of 5e12 Msun of z~2 sub-millimeter galaxies is close to that estimated for the most efficient star formers at the same redshift.  ...


1111.4215
Evidence for DM contraction and a Salpeter IMF in a massive early-type galaxy
Sonnenfeld, Treu, Gavazzi, Marshall, Auger, Suyu, Koopmans, Bolton


Double Einstein ring system: combine lensing and dynamics, constrain mean slope of the total mass density profile rho \propto r^-gamma' within the outer ring to be gamma'=1.98.  Then obtain a bulge-halo decomposition, assuming a power law from the DM halo.  Analysis yields gamma_DM=1.7 for the inner slope of the DM profile (in agreement with DM distribution in ellipticals), and a stellar mass from lensing and dynamics M_*^LD=5.5e11 Msun.  Compare stellar mass inferred from stellar population synthesis, and find Salpeter IMF provides a good description of the stellar population of the lens, while a Chabrier IMF is ruled out at 95% confidence level.  Data suggest growth accretion of small systems from a compact red nugget is a plausible formation scenario for this object.


1111.4216
Multiwavelength constraints on pulsar populations in the galactic center
Wharton, et al


There can be as many as 1e3 active radio pulsars pointed towards Earth in the inner parcec of the Galaxy.


1111.4241
The Atlas 3D project --- XIII. Mass and morphology of HI in early-type galaxies as a function of environment
Serra ... Blitz ..., et al


Nearby early type galaxies (ETG) down to M(HI)~1e7Msun; outside of Virgo, HI in ~40% of ETG, ~10% inside Virgo cluster.  HI morphology: majority a disk/ring, some unsettled gas distributions.   Small disk <1e8Msun confined within the stellar body and sharing the same kinematics as stars, or large discs/rings extending to tens of kpc from the host galaxy and kinematically decoupled from the stars.  Galaxies with central HI exhibit signatures of SF in ~70% of the cases, ~5 times more frequently than galaxies without central HI.  Central ISM dominated by molecular gas---small disc ETGs the conversion of HI into H2 is as efficient as in spirals.  The ETG HI mass function has M*~2e9 Msun and slope=-0.7.  ETGs host much less HI than spirals as a family, but a significant fraction of them is as HI-rich as spirals, difference is that ETGs lack the high-column density HI typical of the bright stellar disk of the latter.  Find envelope of decreasing M(HI) with increasing environment density.  The gas-richest ETGs live in the poorest environments (where star-formation is more common), galaxies in the center of Virgo have the lowest IH content, and cluster outskirts are a transition region.  Find HI morphology-density relation: low environment density, HI is mostly distributed on large disks/rings.  More disturbed HI morphologies dominate environment densities typical of rich groups, confirming the importance of processes occuring on a galaxy-group scale for the evolution of ETGs.


1111.4243
SED fitting with MCMC: methodology and application to large galaxy surveys
Acquaviva, Gawiser, Guaita


GalMC: public MCMC algorithm for SED fitting, and show results for a stacked observation of LAE galaxies at z~3; discuss dependence of the inferred SED parameters on the assumptions maade in modeling the stellar populations.  SpeedyMC is a faster version that uses pre-computed template libraries, which runs a lot faster.


1111.4402
GMASS ultradeep spectroscopy of galaxies at z~2 -- VII. star formation, extinction and gas outflows from UV spectra
Talia et al


Dust extinction estimated from the rest-frame UV continuum stlope; used to obtain dust-corrected star-formation rates for the galaxies of the sample.  A positive correlation between sFR and stellar mass was observed.  Low-ionization absorption lines, associated with the interstellar medium, were found to be blueshifted, with respect to the rest frame of the system, which indicates that there is outflowing gas with typical velocities of the order of ~100 km/s.  Correlation between galaxy UV spectral characteristics and galaxy general properties: report a possible correlation between the equivalent width of the interstellar absorption lines and SFR, stellar mass, and colour excess similar to that seen to hold at different redshifts.  


1111.4434
CHFTLenS: improving the quality of photometric redshifts with precision photometry
Hildebrandt, Erben, ... et al


Correction of systematic effects in the photoz arising from the different PSF in the five optical bands.  Careful homogenization of PSF necessary, gain is particularly pronounced at fainter magnitudes.  ZP corrections are less important if PSF is properly homogenized.