Wednesday. My luggage is supposed to arrive this afternoon, thank goodness.
1106.3194
The evolution of quiescent galaxies at high redshift (z>1.4)
Pozzi, ... Ilbert, Capak, Kneib, Le Fevre, ... et al.
Observe significant evolution of the quiescenet stellar mass function from 2.5<z<3.0 to 1.4<z, while the quiescent population increases from 10% to 50% at the same redshift and mass intervals. Compare models with evolution of fraction of quiescent galaxies, find best model. Find that there is already a significant number of quiescent galaxies at z>2.5.
1106.3328
Cluster Lensing and Supernova survey with Hubble (CLASH)
Postman, Coe, ... Broadhurst ... Graves, ... Moustakas, ... et al
524 multi-cycle treasury program. Gravitational properties of 25 galaxy cluster. Establish degree of concentration of dark matter in the cluster cores. 20 x-ray selected (mostly relaxed), with 5 lensing-selected clusters to check lensing bias. Total of 16 broadband filters from NUV to NIR, 20 orbits per cluster. Magnified z>7 candidates from cluster lenses.
* wow. This is the super-duper version of what we submitted to Hubble ~4 years ago.
1106.3079
Black hole growth in the early universe is self-regulated and largely hidden from view
Treister, Schawinski, Volonteri, Natarajan, Gawiser
Formation of first massive objects, initial conditions of BH seed properties are quickly erased. Deep X-ray observations measure amount of BH growth in z~6-8 galaxies. Early bursts, significant growth, but obscured and do not contribute to the re-ionization of the Universe with their UV emission.
1106.3072
SLUG - Stochastically lighting up galaxies I: Methods and validating tests
da Silva, Fumagalli, Krumholz
A new code to stochastically light up galaxies (SLUG), study the effects of stochasticity on the luminosities of stellar populations (important for understanding populations in the low mass or low star formation rate regime). Stochastic, but includes effects of clustering, stellar initial mass function, SF history, stellar evolution, cluster disruption. Output: catalogs of star clusters and their properties (IMF and photometry), 2D histograms of color-magnitude diagrams of every star in the simulation, photometric properties of field stars and integrated photometry of the entire simulated galaxy. Compare with other code and MW observations.
1106.3183
A Lya blob and zabs ~ zem damped Lya absorber in the DM halo of the binary quasar Q0151+048
Zafar, et al.
* Lya blob: a huge concentration of gas emitting the Lya emission line (recombination of ionized H) into ground state. Found in high z universe (because of redshifting into optical). Appears to be related to AGN jet activity.
Binary quasar (qA and qB) at z~1.929, 3.3" separation. DLA is observed at a higher redshift in qA. Host galaxies of both QSOs detected, as well as a Lya blob.
* a specific measurement on a specific system.
1105.3186
Scaling relations and overabundance of massive clusters at z>~1 from WL studies with HST
Jee, Dawson, Hoekstra, Perlmutter .. Suzuki, ... et al.
* scaling relations of... what?
* overabundant relative to LCDM prediction?
22 (+5) clusters at z>~1, WL studies from HST. Compare WL mass with other observables. Presence of the most massive clusters in our sample in tension with LCDM? Lensing mass tighly correlated with gas temperatures. M-T_X relation of M \propto T_X^alpha, alpha = 1.54 pm 0.23; consistent with self-similar prediction of alpha = 1.5 (3/2). Normalization is, however, lower than previous results by 20-30% at low z---evolution? Existence of massive clusters provide tension with current LCDM model.
* lensing mass-temperature relation at z>~1!
1106.4016
Complete WMAP constraints on bandlimited inflationary features
Dvorkin, Hu
* Cora!
* ..what is a bandlimited inflationary feature?
Test slow roll and single field inflation with WMAP7 data, with PCA which is sensitive, for a feature in the inflation potential or sound speed. Complete analysis for bandlimited features in the source function of generalized slow roll can be used to constraint parameters of specific models of inflaton potential.
* I don't understand this abstract, if that's not obvious.
1106.4018
Predicted constraints on cosmic string tension from Planck and future CMB polarization measurements.
Foreman, Moss, Scott
Fisher forecast on cosmic string tension Gmu. More general simulations that commonly used in the literature.
* whatever.
1106.4022
The emission by dust and stars of nearby galaxies in the Herschel KINGFISH survey
Skibba et al.
Estimate the total emission from dust and stars of 62 nearby galaxies in the KINGFISH survey, from Herschel and ancillary UV and submm data. Interception and re-radiation of radiation by dust. Dust/stellar flux ratio has a range of 3 decades; varies with morphology and total IR luminosity; also related to gas-phase metallicity (not so dust/stellar mass). Substantial scatter between dust/stellar mass and dust/stellar flux. Compare dust/flux and dust temperatures; early-types have slightly warmer temperatures than spirals, probably due to more intense interstellar radiation fields, or different dust grain compositions. Early-types and early-type spirals have strong correlation between dust/stellar flux ratio and sSFR; suggests that the bright far-IR emission on some of these galaxies is due to ongoing star formation and the radiation field from older stars.
* cool. Dust in ellipticals are warmer than in spirals. Didn't quite understand why from the abstract.
1106.4034
Joint QSO-CMB constrains on reionization history
Mitra, Choudhury, Ferrara
* QSO absorption lines, I guess, with CMB.
Decompose the function N_ion(z) [# photons intering per baryon in collapsed objects] into its principal components. Include CMB which seem to contain more info than just the single number tau. Using MCMC, find z<6 ionization is highly constrained, but for z>6 broad range of histories are still permitted. Reionization 50% complete at 9.0<z<11.8 (2sig). With PLANCK, the z>6 reionization will be much better constrained, but need data sets other than CMB.
1106.4264
Enhancements to velocity-dependent DM interactions from tidal streams and shells in the Andromeda galaxy
Sanderson, Mohayaee, Silk
* Joe Silk!
* velocity dependent DM interactions? Shells in Andromeda?
Calculate detection over smooth DM distribution from tidal structure in M31, assuming cross-section is inversely proportional to the relative velocities of the DM particles (Sommerfeld effect; I guess they assume DM has zero angular momenta). More gamma-ray emission compared to the BG (wait, how? "the low velocity in the structure"--the stream has less signal?), calculate expected signal from Fermi.
* Sommerfeld effect:
* sommerfeld enhancement: rate of DM self annihilation, resulting in gamma rays or e-e+ pairs. Rate of this process is the product of the cross section times the incident flux. The estimated rate seems to be too low, from astroparticle observations. But if two particles attract each other, the rate is enhanced (classically: focuses, and increases velocity). Increased velocity changes rate depending on angular momentum; in general it increases the rate, but for zero angular momentum it goes like the inverse of the velocity.
* I don't understand whether the stream should be generating more gamma rays or not. confusing abstract.
1106.4301
The water vapor spectrum of APM 08279+5255
Bradford, et al.
* water vapor?
z=3.91 quasar spectra at Caltech Submillimeter Observatory; 12 CO rotational transitions (dominates CO cooling), and 6 transitions of H2O at energy levels ranging up to 643K (more cooling!). First detections at high z. Assume gas distributed over a 550pc size scale for calculations. H2O cooling comparable to CO cooling. Emission in H2O is similar to low z, but ~x50 higher in luminosity (wow). H2O abundance in good agreement with expectations. Dust continuum in this system pumps the massive reservoir of warm water vapor.
0212216
Neutrino Mass and dark energy from weak lensing
Abazajian, Dodelson
Matter distribution evolution sensitive to DE and neutrino mass. Lensing experiments to measure both features simultaneously. Tight constraint of 0.1eV uncertainty for neutrino mass (as well as DE); most of the restrictive power comes from constraints in distance relations, not matter growth.
Introduction:
The energy density in massive neutrinos and the equation of state of the DE are clearly needed. Both leave similar signatures in the matter distribution in the universe: neutrino inhibit growth of structure (still somewhat relativistic), and DE slows growth of structure. Concentrate on radial tomography (change in shear field of source galaxies in different redshift bins).
Lensing of galaxies at fixed redshift:
Lensing tomography: lensing convergence in different angular pixels. dz = 0.1, angular bin size = 1 deg^2. Comoving distance depends on cosmology (energy density). Growth function depends on neutrino masses (roughly, a fractional decrease in the power on scales probed by lensing surveys equal to 12 f_nu, where f_nu = Omega_nu / Omega_m). For every 1eV of m_mu, the growth is suppressed by ~0.1. The growth rate is affected by both Omega_DE and w, while WL kernel is sensitive mostly to Omega_DE and not to w.
Results:
Two effects measured, (1) evolution of the power spectrum (growth function) and (2) projection of physical distances onto redshift space. Tomography breaks degeneracy between w and Omega_DE (projection more sensitive to Omega_DE than w). Projection is completely independent of neutrino mass; neutrino mass very correlated with w. Future measurements of neutrino mass will contribute to DE param. estimates. Constraints on neutrino from WL alone is not small enough if w and Omega_DE allowed to vary. But cosmo measurements still put limits on neutrino mass--they are not degenerate (i.e., have a mass hierarchy), for example. Uncertainties in the power spectrum from ambiguity in the other parameters (Omega_m h^2, Omega_b h^2, n, A) are projected to be smaller than one percent after Planck.
* to be summarized on Monday.
1106.3327
Cosmic Mach Number as a sensitive test of the growth of structure
Ma, Ostriker, Zhao
CMN: the ratio between the mean velocity and the velocity dispersion of galaxies as a function of cosmic scales. Data consistent with WMAP7 LCDM. CMN is highly sensitive to the growth of structure on scakes 0.01<k<0.1 h/Mpc. Modified gravity and massive neutrino models can be probed with CMN data.
1106.3331
The morphology of galaxies in BOSS
Masters et al
240 COSMOS objects to check morphology of luminous and massive objects at 0.3<z<0.7. Majority posses early type morphology (3/4). Remainder are late-types. (g-i)>2.35 selects 90% early type subset, comparable to the LRG samples; remaining 10% are likely passive spirals. ~25% of early-type galaxies are unresolved multiple systems in SDSS imaging, of which 50% are real associations of "dry mergers". SDSS size systematically larger (by 40%) than HST images, and provide statistical correction for the difference.
1106.3366
The 6dF galaxy survey: BAO and the local hubble constant
Beutler, Blake, et al
Large scale correlation function of the 6dFGS show BAO signal at z=0.106. Find local Hubble constant of H_0 = 67pm3.2 km/s/Mpc that depends only on WMAP7 calibration of the sound horizon and 6dFGS clustering---find w=-0.97pm0.13 from WMAP7 and 6dFGS only. WALLABY (radio) and TAIPAN (optical) are both likely to yield BAO peak detections.
1106.3565
The relationship between black hole growth and star formation in Seyfert galaxies
Diamond-Stanic, Rieke
Estimates of BH accretion rates and SFR of nuclear, extended, and total region of Seyferts. Use Spitzer. BH accretion rate are correlated with nuclear SFR, but completely uncorrelated to the total SFR. AGN duty cycle of 5-10% maintains the ratio between BG and bulge masses seen in the local universe.
* cool.
1106.3766
SZ observations with a statistically complete sample of galaxy clusters with ORCA-p
Lancsaster et al.
* Very weak detection of individual clusters.
30 GHz SZ observations; 18 most x-ray luminous clusters at x>0.2 in ROSAT BCS. All 17 samples (one removed) have y_0 param > 1.9e-4, and 13 are detected at >3 sigma. X-ray/SZ scaling relation (T_X, L_X, M_X proxi Y_X) and find good agreement with predictions from self-similar models. Intrinsic scatter in y_0 is about 25%.
1106.3823
Probability distribution functions of cosmological lensing: convergence, shear, and magnification
Takahashi, Oguri, Sato, Hamana
* 1pt functions of kappa, gamma, mu.
Ray tracing simulations. Convergence and magnification PDFs are closely related to each other via mu = (1-kappa)^{-2} up to the high magnification tail. Mean convergence is negative (over the whole sky), and is correlated with the convergence variance. Simple analytical formulae for the PDFs. Examine SL probability and magnification effects on the luminosity functions.
* nice, useful.
1106.3875
The case for primordial BH as dark matter
Hawkins
* only if PBH's are formed before BBN.
Stellar mass primordial black holes = DM? Then most LOS will be microlensed. Microlens: achromataic and symmetric variations and absence of time dilation. Evidence of stellar mass PBH weakest in MC microlensing--rate too small.
1106.3987
Matter power spectra in dynamical DE cosmologies
Fedeli, Dolag, Moscardini
* ugh.
Use cosmo simulations to investigate gas cooling and SF in LSS. Formation of structures in five different DE models: LCDM + 4 Omega_Lambda(z). DM only run for comparison with +baryon. Dynamical DE introduce a specific signature on the power spectra of matter components, independent of cosmologies considered. Generic shape well capturesed by the halo model. Finder details of the DM power spectrum can be precisely captured only at the cost of a few slight modifications to the model ingredients. Backreaction of baryons onto DM works the same as in ordinary LCDM. Increment in avg concentration is less pronounced than in the fiducial model (~10%). SF less efficient with DE displays dynamical evolution.
* that last line was interesting.
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