1206.4904
Giant Molecular clouds: what are they made from, and how do they get there?
Dobbs, Pringle, Burkert
4 simulations of isolated galaxies: GMCs are not common, they start form and dissipate from/to the ISM with 50 Myr timescales. Gas density within an order of magnitude of GMC from 10 Myr before; dispersal due to stellar feedback; in come cases the gas is never fully recycled. In vertically-averaged velocity fields within the ISM, the shortest timescale can be understood in terms of the various cloud formation and dissipation mechanisms. Properties of the flow patterns can be used to distinguish the processes which drive converging flows (e.g. spiral shocks, SNe) and this molecular cloud formation, and such properties may be detectable with future observations of nearby galaxies.
1206.4905
Elemental nitrogen partitioning in dense interstellar clouds
Daranlot et al
From calculation at ISM conditions (56K and gas-grain model), show N2 formation is inefficient, and most of N reservoir are in the form of labile NH3.
1206.4915
Detection of spectral evolution in the bursts emitted during the 2008-2009 active episode of SGR J1550--5418
Kienlin et al
Series of bursts for soft gamma repeater. 2008 events best fit with single BB function, the 2009 bursts an optically thin thermal bremsstrahlung (OTTB) is clearly preferred. Changes in the B-field topology of the source.
1206.4919
Strong gravitational lens statistics using the Herschel-ATLAS
Short et al
Herschel-ATLAS demonstrate that lens can be identified efficiently at submm wavelengths using a simple flux criteria. Huge number of lenses has great potential for constraining cosmological parameters.
1206.4034
A novel approach to constrain the escape fraction and dust content and high redshift using the cosmic infrared background fractional anisotropy
Fernandez, Dole, Iliev
Use CIB to estimate the escape fraction (magnitude of the fluctuation depend on escape fraction, but the mean intensity does not). Lower values of escape fraction producing higher values of fractional anisotropy, especially at >10 um (this is harder to observe). Fractional anisotropy can also be used to separate dusty from dust-free population.
1206.4938
BD+48 740 - Li overabundant giant star with a planet. A case of recent engulfment?
Adamow et al
1.6 M_J companion with high ellipticity (e=0.67) at a=1.89 AU, P=771d; star has high Li abundance ([Li/H]+12=2.33). Ingestion by the star of a putative second planet in the system originally in a closer orbit could possibly allow for a single explanation of the two facts. First example of the remnant of a multiple planetary system possibly affected by stellar evolution.
1206.4948
Testing the dark energy with gravitational lensing statistics
Cao, Covone, Zhu
Test SCDM, DGP, and Ricci DE models under a spatially flat universe from z-distribuion of early-type gravitational lenses from a collection of 122 systems. Cosmological constant model preferred.
1206.4995
Multiple star formation to the bottom of the IMF
Kraus, Hillenbrand
Frequency and properties of multiple star systems offer powerful tests of SF models. Binary properties vary strongly with mass, but frequency and semi major axis interplay, as well as functional forms, largely unconstrained. Present results of a large-scale survey of multiplicity at the bottom of the IMF in several nearby young associations (78 very low mass binaries): lower-mass binary systems less frequent and more compact (null detection for separation >7AU). Binary frequency and binary separations decline smoothly between masses of 0.5 Msun and 0.02 Msun. Mass ratio concentrated at q~1 for lower masses, although some systems appear to have unusually wide separations and low mass ratios. Compare results to synthetic binary populations from SPH sims (discuss similarities and differences).
[Fri **/43] Jun 22
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