1205.1799
Asymmetric velocity anisotropies in remnants of collisionless mergers
Sparre, Hansen
Typical analysis of DM haloes assume spherically symmetric velocity distributions, but has not been explicitly tested. Find: velocity anisotropy (differences in the radian and tangential velocity dispersion) has a strong dependence on direction; it depends on the merger history, explain why a large diversity is seen in the velocity anisotropy profiles in the outer parts of high-res simulations of haloes.
1205.1800
Deep silicate absorption features in Compton-thick AGN predominantly arise due to dust in the host galaxy
Goulding et al
As the title says. Use Spitzer IRS to measure Si absorption features; explore the origin of MIR dust extinction in all 20 nearby AGN with hard X-ray SED. Conclude that the dominant contribution to the observed MIR dust extinction is dust located in the host galaxy (disturbed morphologies, dust lanes, galaxy inclination angles), and not necessarily a compact obscuring torus surrounding the central engine.
1205.1801
Energetic galaxy-wide outflows in high-redshift ultra-luminous infrared galaxies hosting AGN activity
Harrison, et al
8 high-z ULIRGS with AGN activity, includes SMGs. Targets have moderate radio luminosities typical of high-z ULIRGs (not radio-loud AGNs). Decouple kinematic components due to the galaxy dynamics and mergers from outflows. Find evidence in the most luminous systems for the signatures of LS energetic outflows: broad OIII emission across 4-15 kpc, with high velocity offsets from systemic redshifts (850 km/s); likely to unbind gas from the host galaxies. The radiative power of the AGN, as opposed to SF or radio jets, is likely to dominate the driving outflows. Suggest that galaxies observed may represent a key stage in the evolution of massive galaxies.
1205.1803
Constraining tidal dissipation in stars from the destruction rates of exoplanets
Penev, Jackson, Spada, Thom
Use distribution of extrasolar planets in circular orbits around stars with surface convective zones detected by ground based transit searches to constrain how efficiently tides raised by the planet are dissipated on the parent star. Conclude that the population of currently knoon planets is inconsistent with Q*<1e7 at 3 sigma. Q* required for orbital circularization is 1e5 to 1e7; suggests different dissipation mechanisms between the two, most likely due to the different tidal forcing frequencies relative to stellar rotation frequency for star-star vs planet-star systems.
1205.1808
A population of dust-rich quasars at z~1.5
Dai et al
Herschel SPIRE (250, 350, and 500 um) detections of 32 quasars with 0.5<z<3.6 from Herschel Multi-tiered Extragalactic Survey (HerMES), from 326 quasars in the Lockman hole Field. Construct rest-frame SEDs from UV to MIR for all sources, and to the FIR for the 32 objects. Most quasars with FIR detection show dust temperatures in the range of 25K to 60K, with a mean of 34K. The FIR luminosities range from 1e11.3 to 1e13.5 Lsun (ULIRG or HLIRGs). These FIR-detected quasars may represent a dust-rich population, but with lower redshifts and fainter luminosities than quasars observed at ~1mm. Their FIR properties cannot be predicted from shorted wavelengths (0.3-20 um, rest-frame), and the bolometric luminosities derived using the 5100A index may be underestimated for these FIR-detected quasars. Regardless of redshift, observe a decline in the relative strength of FIR luminosities for quasars with higher NIR luminosities.
1205.1843
Photometric properties of void galaxies in the Sloan digital sky survey DR7 data release
Hoyle, Vogeley, Pan
Photometric properties of 88k void galaxies; compare them to galaxies in higher density environments. Find 1054 dynamically distinct voids with R>10 Mpc/h. Voids are under dense (<-0.9 in their centers). Color (u-r) as indicator of SF activity; inverse concentration index as indication of galaxy type. Void galaxies are statistically bluer than galaxies found in higher density environments with the same magnitude distribution. Little variation in void galaxy properties as function of distance from void center (though dwarf void galaxies may live loser to the center. All void galaxies live in very similar density environments.
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