1210.2391
Evidence for grain growth in molecular clouds: a Bayesian examination of the extinction law in Perseus
Foster, et al
Find strong correlation between the extinction (Av) and the slope of the extinction law (parameterized by Rv). Most extinction comes from Perseus molecular cloud. Interpret results as grain growth at moderate optical depths. For increasing column density from Av=2mag to 10 mag, the extinction law changes from Rv=3 (diffuse) to 5 (dense). Relationship similar for two regions in the study--dust grain growth must be a fairly universal process.
1210.2392
The behaviour of shape and velocity anisotropy in dark matter haloes
Sparre, Hansen
DM haloes are triaxial, and the velocity anisotropy beta is largest along the major axis, and smallest along the minor axis. For each simulated halo, 48 different cones, and compute the velocity anisotropy profiles. Find: elongated haloes can have very distinct velocity anisotropies. 3 different categories in behavior, in beta profiles. Spherically averaged profiles often obey a linear relation between beta and the logarithmic density slope in the inner part of the haloes, but this relation not necessarily obeyed when properties are calculated in cones.
1210.2405
Extended photometry for the DEEP2 galaxy redshift survey: a testbed for photometric redshift experiments
Matthews, Newman, Coil, Cooper, Gwyn
DEEP2 with ugriz photometry (CFHTLS and SDSS) cross-matched, used to predict DEEP2 BRI photometry. Included improved astrometry tied to SDSS (not USNO-A2.0). 27k objects, 64% which have r>23. Generate catalog used for testbed for future photo-z studies for LSST and DES.
1210.2413
The Baryon acoustic oscillation broadband and broad-beam array: design overview and sensitivity forecasts
Pober, Parsons, ... McDonald, McQuinn, Aguirre, et al
21 cm power spectrum for 0.5<z<1.5: BAOBAB array. Will fully correlate dual-polarization antenna tiles over 600-900 MHz with a frequency resolution of 300 kHz and system temperature of 50K. Present calculations of the power spectrum sensitivity for various array sizes, with 35-element array measuring the cosmic neutral hydrogen fraction as a function of z, and a 132-element system detecting the BAO features in the power spectrum, yielding a 1.8% error on the z~1 distance scale; constraining DE EoS over 0.5<z<1.5 (unprecedented).
1210.2432
The challenge of large and empty voids in SDSS DR7 redshift survey
Tavasoli, Vasei, Mohayaee
Generate catalogues of voids from Millennium I Simulation mock data, representing SDSS DR7. Find: voids tend to be spherical, both in sims and observation. Void number and total volume slightly larger in the simulation than in observation. Large voids are less abundant in the simulation, and the total luminosity of the galaxies contained in a void with a given radius is on average higher than observed by SDSS DR7 survey. Expect actual discrepancy to be larger, because sigma_8 < 0.9, the value used in Millennium I sim. Discrepancy probably due to failure of SAM, which fails to reduce the small-scale power of LCDM and fails to produce sufficient power in large scales [i think that's what they're saying].
1210.2446
The weight of emptiness: the gravitational lensing signal of stacked voids
Krause, Chang, Dore, Umetsu
As the title says. With shear and magnification. Stacking helps with statistical precision, even with miscentering and projection effects. DETF stage IV surveys (Euclid, LSST) can detect void lensing signal with sufficient precision from stacking abundant medium-sized voids, thus providing direct constraints on the matter density profile of voids independent of assumptions on galaxy bias.
1210.2471
Exoplanet detection methods
Wright, Gaudi
Review of various methods of detecting exoplanets: radial velocities, astrometry, direct imaging, transits, and gravitational microlensing. Basic observable phenomena, physical properties of planets and host stars that can be derived. General experimental requirements. Compare methods, stress complementarity. History of exoplanet detections (briefly).
1210.2480
Constraining the substructure of dark matter haloes with galaxy-galaxy lensing
Li, Mo, Yang, van den Bosch
GG lensing signal around satellite galaxies in different host haloes, and located at different halo-centric distances. Use MCMC to explore the potential constraints on the mass and density profile of subhaloes associated with satellite galaxies (SDSS and LSST-like). Results: SDSS can only set a loose constraint on the mean mass of sub haloes. With LSST-like surveys, both the mean mass and the density profile of subhaloes can be well constrained.
1210.2496
GENJI programme: Gamma-ray emitting notable AGN monitoring by Japanese VLBI
Nagai et al
Monitoring program of gamma-ray bright AGNs with VERA, at 22 GHz (radio). Investigate the radio time variation of the core and possible ejection of new radio component, motion of jest, and the relation with the emission at other wavelengths especially in gamma-rays. Currently 8 AGNs monitored, once every 2 weeks. Trace trend of radio time variation on shorter timescale than conventional VLBI monitoring program me, and to provide complimentary data with them (eg MOJAVE). Quick followups.
1210.2518
Probing the early universe with the CMB scalar, vector and tensor bispectrum
Shiraichi
PhD thesis.
1210.2521
GOODS-Herschel: radio-excess signature of hidden AGN activity in distant star-forming galaxies
Del Moro et al
As the title says.
1210.2532
Simulated histories of reionization with merger tree of HII regions
Chardin, Aubert
As the title says. From the merger tree of ionized patches, one can track the individual evolution of the regions (size), or properties of the percolation process (look at formation rate, frequency of mergers, and number of individual HII regions).
1210.2578
Galaxies going MAD: the galaxy-finder comparison project
Knebe, .. Behroozi, ... et al
Object finders for simulations: comparison pojrect for DM field haloes, and DM subhaloes previously reported. Baryonic physics in sims also. Report: comparison codes as applied to CLUES (constrained local universe simulation) of the formation of the Local Group which has most of the formation physics. Compare properties of 3 main galaxies in simulation (MW, M31, M33 representation) and their satellite populations for a variety of halo finders ranging from phase-space to velocity-space to spherical over density-based codes. Better agreement amongst codes than the other comparison projects, for total, dark and stellar components of objects. But for diffuse gas content, there is great disparity, specially for low-mass satellite galaxies, due to differences in the treatment of the thermal energy during the unbinding procedure. Handling of gas in halo finders must be carefully dealt with, treatment may depend on the problem being studied.
1210.2649
Clustering of far-infrared galaxies in the AKARI All-sky survey
Pollo, et al
Preliminary study, systematics (difference between north and south hemisphere) found.
1210.2692
A close-pair analysis of damp mergers at intermediate redshifts
Chou, Bridge, Abraham
Study kinematics of ~2800 0.1<z<1.2 galaxy pairs from CFHTLS field. Find: 1/5 likely to share DM halo. Red-red pairs almost absent, suggesting that damp mergers are rare at z~0.5. Support models with a short merging timescale (<0.5 Gyr) in which SF is enhanced in the early phase of mergers, but quenched in the late phase. Hot halo models may explain this behaviour, but only if virial shocks that heat gas are inefficient until major mergers are nearly complete.
1210.2696
Interpolating point spread function anisotropy
Gentile, Courbin, Meylan
Modeling of the PSF shape and its spatial variation across the instrument crucial. Reliable interpolation scheme mandatory, typically use low-order bivariate polynomials. Study 4 other classical spatial interpolation methods based on splines (B-splines), inverse distance weighting (IDW), radial basis functions (RBF) and ordinary Kriging (OK). Tested on GREAT10 star challenge, compared with PolyFit. RBF is the clear winner, followed by IDW and OK. PolyFit and B-splines are largely behind, especially in fields with (ground-based) turbulent PSFs. In fields with non-turbulent PSFs, all interpolators reach a variance on PSF systematics better than 1e-7 upper bound expected by future space-based surveys, with the local interpolators performing better than the global (PolyFit & spline) ones.
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