1203.3801
Unidentified gamma-ray sources: hunting gamma-ray blazars
Massaro, D'Abrusco, Tosti, Ajello, Gasparrini
UGS: about 1/3 of Fermi-objects still not associated to low energy counterparts. Use IR (blazars have a specific IR color) to associate gamma-ray sources; of the 313 UGSs, 156 blazar candidates found.
1203.3802
The interaction between feedback from active galactic nuclei and supernovae
Booth, Schaye
Both AGN and SNe are processes that are thought to control how much gas is able to condense into galaxies and form stars. Show that both suppress star formation, but they mutually weaken one another's effect by up to an order of magnitude in haloes in the mass range for which both feedback processes are efficient (log(M_200/M_sun) of 11.25 ~ 12.5). [Why?] Cannot expect two effects to be independent, which most SAMs assume.
1203.3803
Line transfer through clumpy, large-scale outflows: Lyman alpha absorption and haloes around starforming galaxies
Dijkstra, Kramer
Can the Lya halos observed around Lyman break galaxies be quantitatively explained (with constrained radiative transfer calculations of Lya photons propagating through clumpy, dusty, large scale outflows)? Use large scale outflows of cold clumps in pressure equilibrium with hot wind; first consider cold clumps are symmetrical around galaxy, in circumgalactic medium (CGM). Constrain cold clump properties (radius, velocity, HI column density, number density) from Lya strength, then insert Lya source in the center of clumpy outflow (1e5-6 clumps); compute observable properties of scattered Lya photons. This forms scattered radiation that are more concentrated than observed. To reproduce observed Lya absorption line strengths and Lya haloes, (bipolar) outflows required, in which the clumps decelerate after their initial acceleration. Consistent with 'momentum-driven' wind models of clumpy outflows. Predict linear polarization 30-40% at a surface brightness contour of 1e-18 erg/s/cm^2/arcsec^2. Work illustrates the Lya emission line halos around star forming galaxies provide valuable constraints on the cold gas distribution & kinematics in their circumgalactic medium; complement absorption line studies.
1203.3806
Detectable seismic consequences of the interaction of a primordial black hole with Earth
Luo, Hanasoge, Tromp, Pretorius
Primordial BHs passing nearby Earth will cause simultaneous Earthquakes (magnitude 4 for 1e15g BH) on Earth, although the expected collision rate is 1e-7/yr (very unlikely), even if PBHs are DM.
1203.3809
Foreground predictions for the cosmic microwave background power spectrum from measurements of faint inverted radio sources at 5 GHz
Schneider, Becker, de Vries, White
Measurements of a population of matched radio sources at 1.4 and 5 GHz down to flux limit (1.5 mJy) in 7 sq. deg. of NOAO DFS. Large fraction of sources have inverted spectral indices; many undetected in previous radio source counts. Update number counts of 5 GHz differential number counts and distribution of spectral indices. Modified number counts yield at most 10% change in the predicted Poisson contribution to the Planck temperature power spectrum.
1203.3823
Shapes and probabilities of galaxy clusters II: comparisons with observations
Yang, Saslaw
Estimate kinetic and correlation potential energies [?] of low-z clusters and groups in SDSS. Energy distribution agrees with their prediction from another paper.
1203.3824
The first stars and galaxies -- Basic principles
Bromm
[Summer School lecture notes]: Understanding the formation of the first stars and galaxies. Cosmological context, cooling and chemistry in primordial gas, physics of gravitational instability, main properties of the first stars. Observational signature of the first sources of light.
1203.3827
Where will Einstein fail? Lessons for gravity and cosmology
Afshordi
Review observational cosmology in the past three decades; summarize pathologies in Einstein's GR; addressing pathologies via mathematical elegance, or empirical falsifiability (violates Lorentz symmetry). Deviation from Einstein's gravity expected in: 1) cosmological matter-radiation transition, 2) neutron stars, 3) gravitomagnetic effect, 4) astrophysical black holes (and DE), 5) early universe.
1203.3830
Variability of Mini-BAL and BAL outflows in quasars
Hidalgo, Hamann, Eracleous, Capellupo, Charlton, Shields
Study high velocity BAL to better characterize the structural and physical properties of outflows. Compare SDSS spectra and monitoring campaign spectra; 57% of quasars with mini-BALs and BALs varied between two observations; all variable lines vary in intensity and not in velocity (no evidence for acceleration/deceleration in outflows).
1203.3881
Synchrotron and inverse-Compton emission from blazar jets I: a uniform conical jet model
Potter, Cotter
Revisit class of models where the jet has uniform conical ballistic structure. Consider synchrotron and synchrotron-self-Compton emission from the jet, modeling the recent simultaneous multi-wavelength observations of BL Lac. Find no requirement for significant re-acceleration within the jet to explain the observed spectrum.
1203.3899
The DEEP2 galaxy redshift survey: The Voronoi-Delaunay method catalog of galaxy groups
Gerke, Newman, Davis, Coil, Cooper, Dutton, Faber, Guhathakurta, Konidaris, Koo, Lin, Noeske, Phillps, Rosario, Weiner, Willmer, Yan
Catalog contains 1165 groups with two or more members in the EGS over 0<z<1.5 and 1295 groups at z>0.6 in the rest of DEEP2. 25% of EGS galaxies and 14% of high-z DEEP2 galaxies are assigned to galaxy groups, detected from VD method. Group catalog is 72% complete and 61% pure (74% and 67% for EGS) and that the group-finder correctly classifies 70% of galaxies that truly belong to groups, with an additional 46% of interloper galaxies contaminating the catalog (66% and 43% for EGS).
1203.3986
A large group of asymptotic giant branch stars in the disk of M31: a missing piece of the puzzle?
Davidge
Clump of 1kpc size near the center of M31 (~3.5 kpc away): low surface brightness, round, integrated brightness of M_K=6.5; populated by stars with ages >100 Myr and J-K colors bluer than stars in surrounding disk. Similar profile to dwarf galaxies at this brightness. A satellite seen against M31? fossil star-forming region?
1203.4097
The missing massive satellites of the Milky Way
Wang, Frenk, Navarro, Gao
Only three of the twelve brightest satellites of the NW inhabit DM haloes with maximum circular velocity, V_max, exceeding ~30 km/s; in apparent contradiction with the LCDM simulations of the Aquarius Project, which says a minimum of 8 sub halos with V_max>30 km/s should exist. But number of massive sub haloes depends strongly on (poorly-known) virial mass of the MW; uncertainty in simulations. Invariance of the scaled sub halo velocity function (relation of number of sub halos as a function of ratio of Vmax to V200) used to secure improved estimates of the abundance of rare massive subsystems. In the range 0.1<nu<0.5, N_sub(>nu) is Piosson-distributed about an average given by <Nsub>=10.2(nu/0.15)^-3.11; slightly lower than in Aquarius halos, but consistent with Phoenix Project results. Probability for 3 or less sub halos above a certain Vmax computed: ~40% of 1e12 Msun halos pass the test; <5% do so for M200>2e12Msun.
1203.4143
Multi-scale harmonic model for solar and climate cyclical variation throughout the Holocene based on Jupiter-Saturn tidal frequencies plus the 11-year solar dynamo cycle
Scafetta
Sunspot record of 3 major cycles (9.98, 10.9 and 11.86 years), corresponds to spring tidal period of Jupiter and Saturn (9.93) and the tidal sidereal period of Jupiter (11.86). They generate a beat pattern. The Oort, Wolf, Sporer, Maunder and Dalton minima "hindcasted"; can hindcast for the past 12k years. Solar and climate oscillations are linked to planetary motion, and their timing can be reasonably hind cast and forecast for millennia. Next grand minima: 2020-2045.
1203.4184
The initial conditions of the universe from constrained simulations
Kitaura
New approach to recover the initial conditions and the cosmic web structure underlying a galaxy distribution. First step: Gaussianization, transform distribution of point sources at Lagrangian positions into linear alias-free Gaussian field. Second step: matching procedure in which the set of matter tracers at the initial conditions is constrained on the galaxy distribution and the structure formation model assumed. Demonstrate: take SAM mock catalog that the recovered initial conditions are closely unbiased with respect to the actual ones from the corresponding N-body simulation, down to scales of few Mpc/h. Cross-correlation show a substantial gain of information, doubles info at k~0.3 h/Mpc. Initial conditions well distributed in Gaussian; power spectra follow the shape of the linear power-spectrum being very close to the actual one down to k~1 Mpc/h.
1203.4197
Is the cosmological coincidence a problem?
Sivanandam
Matching DE and DM densities is not a fine-tuning problem ("coincidence problem"), but an artifact of anthropic selection.
1203.4208
The Astro-WISE
McFarland, Helmich, Valentijn
Novel approach to quality control in processing of astronomical data. Quality control integral to all aspects of data handling and provides transparent access to quality estimators for all stages of data reduction from the raw image to the final catalog. The implementation of quality control mechanisms relies on the core features of this Astro-WISE Environment (AWE): an object-oriented framework, full data lineage, and both forward and backward chaining. Quality control information can be accessed via the command-line awe-prompt and the web-based Quality-WISE service. The quality control system is described and qualified using archive data from the 8 CCD Wide Field Imager (WFI) instrument on the 2.2m MPG/ESO telescope at La Silla and (pre-)survey data from the 32 CD OmegaCAM instrument on the VST telescope at Paranal.
1203.4219
Detection of galaxy cluster motions with the kinematic Sunyaev-Zel'dovich Effect
Hand, ...Das, Dawson, Devlin, Dunkley, ..Eisenstein, .. Halpern, et al
With ACT, detect motions of galaxy clusters and groups in CMB due to kSZ effect. Clusters identified via BOSS (part of SDSS III). The mean pairwise momentum of clusters measured at a statistical significance of 2.8 sigma, and the signal is consistent with the growth of cosmic structure in the standard model of cosmology.
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