Day 397

Thursday.

1102.4349
Integral field spectroscopy of massive, kiloparsec-scale outflows in the infrared-luminous QSO Mrk 231
Rupke, Veilleux

Unambiguous detection of a wide-angle, kpc scale outflow from this QSO, using neutral gas absorption.  how that the nuclear region hosts an outflow with blueshifted velocities reaching 110 km/s, extending 2-3 kpc from the nucleus in all directions in the plane of the sky [wow].  A radio jet impacts the outflow north of the nucleus, accelerating it to even higher velocities (up to 1400 km/s).  3.5 kpc south of the nucleus, SF is simultaneously powering an outflow that reaches more modest velocities of only 570 km/s.  Blueshifted ionized gas is also detected around the nucleus at lower velocities and smaller scales.  The mass and energy flux from the outflow are >2.5x the SFR and >~0.7% of the AGN luminosity, consistent with feedback models of QSOs.

1303.6629
Early-type galaxy archeology: ages, abundance ratios, and effective temperatures from full-spectrum fitting
Conroy, Graves, van Dokkum

Model stacked spectra of early-type galaxies from SDSS as a function of sigma (dispersion velocity) from 90 to 300 km/s.  High quality spectra used (S/N~1000/A), covering 4000A-8800A.  Population synthesis model includes variation in 16 elements from C to Ba, the shift in effective temperature of the stars wrt a solar metallicity isochrone, and other params.  Fit the full optical spectra, measure the abundances of the elements V, Cr, Mn, Co and Ni from the integrated light of distance galaxies.  Main results: (1) light-weighted stellar ages range from 6-12 Gyr from low to high sigma, (2) [Fe/H] varies by less than 0.1 dex across the entire sample, (3) Mg closely tracks O, and both increase from 0.0 at log sigma to 0.25 at high sigma; Si and Ti show a shallower rise with sigma, and Ca tracks Fe rather than O; (4) The iron peak elements V, Cr, Mn, and Ni track Fe, while Co tracks O, suggesting that Co forms primarily in massive stars, (5) C and N track O over the full sample, and [C/Fe] and [N/Fe] exceed 0.2 at high sigma; and (6) the variation in Delta (T_eff) with total metallicity follows theoretical predictions based on stellar evolution theory.  Derived [Mg/Fe] and [O/Fe] abundance ratios are 0.05-0.1 dex lower than most previous determinations.  Under the conventional interpretation that the variation in these ratios is due to star formation timescale variations, results suggest longer SF timescales for massive early-type galaxies than previous studies.

1303.6631
Insights into the content and spatial distribution of dust from the integrated spectral properties of galaxies
Chevallard, Charlot, Wandelt, Wild

Content and spatial distribution of dust in structurally unresolved SF galaxies from the observed dependence of the integrated spectral properties on galaxy inclination.  Combine radiative transfer (RT) model in dusty media with prescription for the spectral evolution of galaxies, via the association of different geometric components of galaxies with stars in different age ranges.  Show that a wide range of RT models all predict a quasi-universal relation between slope of the attenuation curve at any wavelength and V-band attenuation optical depth in the diffuse ISM, at all galaxy inclinations.  The relation predicts steeper (shallower) dust attenuation curves than both the Calzetti and MW curves at small (large) attenuation optical depths, which implies that geometry and orientation effects havae a stronger influence on the shape of the attenuation curve than changes in the optical properties of dust grains.  Interpret 23k SF galaxy attenuation curves.  Measure the face-on B-band optical depth of this sample to be tau_B perp ~1.8pm0.2.  Quantify the enhanced optical depth towards newly formed stars in birth clouds, find it to be significantly larger in galaxies with bulges than in disc-dominated galaxies, while tau_Bperp is roughly similar in both cases.  Show that neglecting the effect of geometry and orientation on attenuation can severely bias the interpretation of galaxy spectral energy distributions, ad the impact of broadband colors can reach up to 0.3-0.4 mag at optical wavelengths and 0.1 mag at NIR ones.

1303.6644
The WiggleZ dark energy survey: constraining galaxy bias and cosmic growth with 3-point correlation functions
Marin, Blake, et al

3pt corroation function for 187k galaxies; scale and shape dependence at z=0.35, 0.55, and 0.68, the highest redshifts where these measurements have been made to date.  Compare with N-body sim results, constrain linear and NL bias of galaxies wrt DM, marginalise over them to obtain sigma_8(z).  Consistent with LCDM predictions.

1303.6689
Evolution of galaxies and their environments at z=0.1 to 3 in COSMOS
Scoville et al

The galaxy properties (M*, SEDs and SFRs) are strongly correlated with environmental density and redshift, particularly at z<1.0-1.2.  Classifying the spectral type of each galaxy using the rest-frame b-i color (from the photoz SED fitting), find a strong correlation of early type galaxies (E-Sa) with high density environments, while the degree of environmental segregation varies systematically with redshift out to z~1.3.  In the highest density regions, 80% of the galaxies are early types at z=0.2 compared to only 20% at z=1.5.  The SFRs and the SF timescales exhibit clear environmental correlations.  At z>0.8, the SFR density is uniformly distributed over all environmental density percentiles, while at lower z the dominant contribution is shifted to galaxies in lower density environments.
1303.6725
HerMES: a deficit in the surface brightness of the cosmic infrared background due to galaxy cluster gravitational lensing
Zemcov, Blain, Coorey, ... Haltern, Jullo, Kneib, ... et al

Observation of 4 massive clusters with Herschel SPIRE: measure a deficit of surface brightness within their central region, after subtracting sources.  Simulate the effects of instrumental sensitivity and resolution, the source population, and the lensing effect of the clusters to estimate the shape and amplitude of the deficit.  The amplitude of the central deficit is a strong function of the surface density and flux distribution of the background sources.  Find that for the current best fitting faint end number counts, and excellent lensing models, the most likely amplitude of the central deficit is the full intensity of the CIB.  Integrated total intensity of CIB of L(250 um)>0.69 pm 0.1ish MJy/sr, with more CIB possible from both low-z sources and from sources within the target clusters.  Should be possible to observe this effect in existing high angular resolution data at other wavelengths where the CIB is bright, which would allow tests of models of the faint source component of the CIB.