0908.3468
Precision astrometry of a sample of speckle binaries and multiples with the adaptive optics facilities at the Hale and Keck II telescopes
Helminiak, Konacki, Kulkarni, Eisner
AO facility at 200-in Hale and 10-m Keck; use near-diffraction limited images; correct for the influence of differential chromatic refraction and chip distortions in relative astrometric measurements. Get precision down to well below 1 milli arc second, good enough to detect planetary mass objects of nearby binary and multiple stars.
1206.2640
A model of the anisotropic correlation function xi(rp, pi) in redshift space including redshift errors
Schlagenhaufer, Phelps, Sanchez
Study influence of redshift inaccuracies on photo-z + galaxy distribution surveys. Simulate the influence of a gaussian redshift error distribution with an absolute rms of sigma_z = 0.015, 0.03, 0.06, and 0.12. Objects of the full shape of xi(rp, pi) is modeled accurately enough to constrain w_DE and linear bias b, even for sigma_z=0.06.
1206.2641
The intense starburst HDF850.1 in a galaxy overdensity at z=5.2 in the Hubble Deep Field
Walter et al
Found the redshift of a galaxy (millimeter wave molecular line) only detected in 850nm to be z=5.2; its SFR is 850 Msun/yr, extremely high for its redshift. Implied dynamical mass of 1.3e11 Msun (significant fraction molecular gas). No starlight counterpart found yet.
1206.2642
Bolometric luminosities and Eddington ratios of X-ray selected active galactic nuclei in the XMM-COSMOS survey
Lusso et al
Find (on average) Eddington ratio increases with redshift for all types of AGN at any given Mbh, while no clear evolution with redshift is seen at any given Lbol.
1206.2643
A spectroscopic study of type Ibc supernova host galaxies from untargeted surveys
Sanders et al
Targeted SN Ibc host environment studies have been biased towards high-mass, high-metallicity galaxies by focusing on SNe discovered in galaxy-targed SN searches. This doubles the total number of spectroscopic stellar population age and metallicity measurements for untargeted SN Ibc host environments. Demonstrates that galaxy-targeted SN searches introduce significant bias for metallicity distribution of SN progenitors [doesn't say which way, but presumable higher metallicity], discuss other systematic effects.
1206.2644
First direct direction limits on sub-GeV dark matter from XENON10
Essig et al
DM scatter with electrons, which cause ionization of atoms leading to single- or few-electron events. Strongest bound obtained at 100 MeV at sigma_e<3e-38 cm^2 at 90% CL, larger for 20 MeV or 1GeV.
1206.2645
Halpha equivalent widths from the 3D-HST survey: evolution with redshift and dependence on stellar mass
Fumagalli, et al
Consistently determine the evolution of EW(Halpha) distribution from z=0 to z=2.2. Find: at all masses the characteristic EW(Halpha) is decreasing towards the current epoch, and at each z, the EW is lower for high-mass galaxies. [is the EW indicator of SFR? seems that way.] Find (with some dependence on the model) that the sSFR evolves as (1+z)^3.2, nearly independent of mass, and consistent with previous reddening insensitive estimates.
1206.2653
Constraining the variation of fundamental constants at z~1.3 using 21-cm absorbers
Rahmani et al
Delta_x/x consistent with 0 to 1e-6, where x = g_p * alpha^2/mu, where g_p is the proton gyromagnetic factor, alpha is the fine structure constant, and mu is the proton-to-electron mass ratio. Use 21-cm absorption line.
1206.2659
Gamma-ray burst host galaxies as probes of galaxy formation and evolution
Levesque
As the title says. The abstract gives little details. Conference proceedings.
1206.2661
Black Hole -- galaxy co-evolution
Schawinski
Review co-evolution motivation, current state of observational picture, and some challenges by BH feed back. Conference proceedings.
1206.2680
Extended and filametary Lyman alpha emission from the formation of a protogalactic halo at z=2.63
Rauch, et al
Report observation of extended LyA emitting halo at z=2.63, spatially coincident with a concentration of faint (and hence no spec-z) galaxies, which probably form a MW halo-mass group at that redshift. A filamentary structure, possibly consisting of LyA emission at very high equivalent width, and evidence for disturbed stellar populations, suggest that the properties of the emitting region reflect ongoing galaxy assembly. LyA powered by cooling radiation or spatially extended SF in the halo, but unlikely powered by AGN or galaxy-source fluorescence. Spatial profile different from typical LyA emitters or Ly-break galaxies: consistent with extended emission of this kind represents a different stage in the galaxy formation process, but rather a faint, extended version of LyA blobs. Halos of interacting galaxies may e significant sources for ionizing photons during EoR.
1206.2693
Quantifying astrophysical uncertainties on dark matter direct detection results
Fairbairn, Douce, Swift
Estimate the uncertainty in the constraints on the spin independent dark matter-nucleon cross section due to the lack of knowledge of the DM phase space in the galaxy. Uncertainty in the interpretation of direct detection experiments of high (>100 GeV) mass DM candidates is less than an order of magnitude in cross section.
1206.2732
Predictions for the intrinsic UV continuum properties of star forming galaxies and the implications for inferring dust extinction
Wilkins, et al
UV continuum slope is potentially a powerful diagnostic of dust obscuration in SF galaxies, but the slope is also sensitive to the form of the IMF and to the recent SF and metal enrichment histories of a galaxy. Use galform SAM galaxy formation model, investigate the intrinsic distribution of UVC slopes. Find sigma_beta=0.30 (slope), and also that the intrinsic UVC slope correlates with SFR, UV luminosity, stellar mass and redshift, which affects interpretation of trends from UVC slope. Past dust attenuation estimates possibly incorrect.
1206.2759
Lithium destruction and production observed in red giant stars
Uttenthaler, et al
As the title says. Proceedings from a workshop.
1206.2832
Forecasting isocurvature models with CMB lensing information: axion and curvaton scenarios
Santos, Cabella, Balbi, Vittorio
CMB lensing can improve the best parameter error estimation for all cosmo params. For isocurvature amplitude, improvement is model dependent. CMB lensing enables degeneracy break between isocurvature amplitude and correlation phase in one of the models.
1206.2838
DEUS full observable (\Lambda}CDM universe simulation: the numerical challenge
Alimi et al
N-body sim of full observable universe: 550 billion particles on AMR grid with >2 trillion computing points along the entire evolutionary history of the universe and across 6 order of magnitudes length scales, from MW size scale to the whole observable universe. >300TB of memory for 10 million hours of computing time. 50PB of data generated throughout the run. Amount of useful data stored reduced to 500 TB.
1206.2851
The interplay of CMB temperature lensing power reconstruction with primordial non-Gaussianity of local type
Merkel, Schaefer
CMB lensing potential power spectrum reconstruction is biased if CMB has primoridal non-Gaussianity, considerably larger than previous analytical calculations, but this bias is completely negligible on all but the largest angular scales.
1206.2887
GRB 090618: the first example of a neutron star gravitational collapse to a black hole induced by a type Ib/c supernova
Izzo, Rueda, Ruffini
Evidence of a SNe ~10 days after the GRB occurence: shown that the NS reaches in a few seconds the critical mass and undergoes gravitational collapse leading to the emission of a GRB. [wait, what about the SNe collapse?]
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