1203.1612
The missing cavities in the SEEDS polarized scattered light images of transitional protoplanetary disks: a generic disk model
Dong et al
Transitional circumstellar disks around young stellar objects have 10um IR deficit in their SED, suggesting dust depletion in the inner regions; giant cavities confirmed by sub-mm imaging. But the polarized NIR scattered light images for most objects show no evidence for the cavity. Radiative transfer modeling indicates that many of these scattered light images are consistent with a smooth spatial distribution for um-sized grains, with little discontinuity in the surface density of the um-sized grains at the cavity edge. Present a generic disk model that can simultaneously account for the general features of all observations. Decoupling between the spatial distributions of the um-sized dust and mm-sized dust inside the cavity is suggested by the model: necessitates a dust filtration mechanism in the cavity clearing process. [I guess the sub-mm data indicates lack of mm-sized grains in the inner region?] Model also suggests an inwardly increasing gas-to-dust-ratio in the inner disk, and different spatial distributions for the small dust inside and outside the cavity, echoing the predictions in grain coagulation and growth models.
1203.1613
Extreme star formation in the host galaxies of the fastest growing suer-massive black holes at z=4.8
Mor, Netzer, Trakhtenbrot, Shemmer, Lira
25 optically selected AGNs at z=4.8, observe with Herschel, find 5 to have 2.8-5.6k Msun/yr SFR, the rest aver to 700 Msun/yr, in any case, very high SFR. Suggest that they (at their peak AGN activity) are in large mergers. AGN feedback responsible for diminishing SF activity in the 20, but not in the 5.
1203.1614
Strong evolution of X-ray absorption in the Type IIn SN SN2010jl
Chandra, et al
Most of x-ray emission characterize high temperature (>10keV), likely to be from forward shocked region resulting from circumstellar interaction. Absorption column density is high 1e24 cm^-2, more than 3 orders of magnitude higher than the Galactic absorption column. In the second epoch, column density decreased by a factor of 3 (expected for shock propagation in the circmstellar medium). Unabsorbed luminosity in both epochs: 7e41 erg/s. Fe line at 6.4 keV present in first but not second epoch. There is a BG ultra luminous x-ray source.
1203.1620
Dynamical measurements of BH masses in four brightest cluster galaxies at 100 Mpc
McConnell, Ma, .. Lauer, Graham, Wright, et al
Report BH masses from stellar kinematics and orbit superposition models of the central regions of four BGCs; integral-field spectroscopy from <100pc to 1e4.x kpc. BH masses of 1e9~10 Msun. Stellar orbits near the center of each galaxy tangentially biased [?]. Find possible evidence for an eccentric torus of stars in NGC 4889, with a radius of nearly 1kpc. Compare measurements of M_BH to the predicted BH masses from M_BH and stellar velocity dispersion (or luminosity, stellar mass) relations. These BHs are significantly more massive than all dispersion-based predictions, and most luminosity based-predictions.
1203.1623
Formation and hardening of SMBH binaries in minor mergers of disk galaxies
Khan, et al
[what is a hard binary?] Look at shrinking of the SMBH binary due to 3-bod encounters with the stars. Constant hardening rates, develop high eccentricity. Coalescence time is 2.9 Gyr (an upper limit).
1203.1625
Dependence of quenching of central and satellite galaxies at z=0 and z=1 on halo mass and distance from its center
Woo, Dekel, Faber, Noeske, Koo, Gerke, Cooper, Salim, Dutton, Newman, Weiner, Bundy, Willmer, Davis, Yan
Use SDSS (z~0.1) and AEGIS (z~1) to study the dependence of SF quenching on galaxy masses and environment. Stellar mass M*, halo mass Mh, density to Nth nearest neighbor deltaN, distance to halo center D addressed. Quenching defined by low SFR (not color; 1/3 of red galaxies are star forming). Fraction of quenched galaxies mostly depends on Mh; for satellites it also depends on D; for centrals the quenched fraction depends only weakly on deltaN and M* at low z, but somewhat more at z~1, when the quenched fraction and Mh are lower. For satellites, M*-dependent quenching noticeable at high D, reflecting quenching dependence on sub-halo mass for recently captured satellites. At small D, quenching depends on Mh, and not on M*. The Mh-depencence of quenching consistent with theoretical wisdom where virial shock heating in massive haloes shuts down accretion and triggers ram-pressure stripping, causing quenching. Interpretation of deltaN depends on the number of observed group members compared to N, motivating the use of D as a better measure of local environment.
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