Saturday. Good night of observation last night. Hope to continue with good observation tonight.
1202.2884
Joint Ly-a emitters: quasars reionization constraints
Baek, Ferrar, Semelin
Use of LAE as reionization probes is hampered by the fact that their Ly-a line is damped internally by dust. Novel method to overcome this degeneracy: joint spectral information from high-z LAE and QSOs. (1) Carefully calibrate a reionization simulation with QSO absorption line experiments. (2) Identify LAEs in two simulation boxes at z-5.7 and 6.6, and build synthetic images/spectra of a prototypical LAE. At z-5.7, find Ly-a transmissivity ~0.25, almost independent of the halo mass. Constancy arises from two effects: (1) the intrinsic Ly-a line width and (2) the infall peculiar velocity [faster infall for higher halo mass, I guess, but what does that have to do with transmissivity being constant?]. At z=6.6, transmissivity increases with halo mass from 0.15 to 0.3, because it is set by the local HI abundance. Although outflows are present, their are efficiently pressure-confined by infall in a small region around the LAE, hence they only marginally affect transmissivity. Finally, cast LOS originating from background QSOs passing through foreground LAEs at different impact parameters and compute the quasar transmissivity. At small impact parameters (d<1 Mpc), a positive correlation between transimissivity and halo mass is found at z=5.7, but tends to become flat at larger distances. By X-correlating LAE and QSO transmissivity, can obtain a HI density estimate unaffected by dust. At z=5.7, the cross-correlation is relatively weak, whereas at z=6.6 can find a clear positive correlation. Conclude by briefly discussing the perspectives for the application of the method to existing and forthcoming data.
1202.2889
Cosmological parameters constraints from galaxy cluster mass function measurements in combination with other cosmological data
Burenin, Vikhlinin
Cosmo parameter constraints obtained from the combination of galaxy cluster mass function measurements with new data: WMAP, SPT, H0, BAO and SNIa. New constraints on total neutrino mass and effective number of neutrino species are obtained. In models with free number of massive neutrinos, the constraints on these parameters are notably less strong, and all considered cosmological data are consistent with non-zero total neutrino mass Sigma m_nu~0.4 eV and larger than standard effective number of neutrino species, N_eff ~ 4. These constraints are compared to the results of neutrino oscillations searches at short baselines. The updated DE EoS parameters constraints are presented. Show that taking in account systematic uncertainties, current cluster mass function data provide similarly powerful constraints on DE EoS, as compared to the constraints from SNIa observations.
1202.2897
Internal stellar kinematics of M32 from the SPLASH survey: Dark halo constraints and the formation of compact elliptical galaxies
Howley, ... Geha, ... Kirby, et al
Imply that, in shaping of cE (compact elliptical, like M32), tidal stripping may not be as significant, from the kinematics of M32, measured out to ~1kpc. Rotation curve and velocity dispersion profile measured, statistically removing M31 effects. M32 kinematics are regular and symmetric and do not show obvious sharp gradients; models with constant M/L can fit the data remarkably well. Half a dozen stars are fast moving, but they may not be bound to M32.
1202.2899
Detailed abundances in stars belonging to ultra-faint dwarf spheroidal galaxies
Francois et al
Close UFdSph chemical composition abundance: slightly lower abundance ratio to what is measured in field halo star of the same metallicity. No extreme abundances in Hercules stars found; synthesis of the neutron capture elements Ba and Sr seem to originate from the same nucleosynthetic process in operation during the early stages of the galactic evolution.
1202.2902
Regularization techniques for PSF-Matching kernels. I. Choice of kernel basis
Becker, Homrighausen, Connolly, Genovese, Owen, Bickerton, Lupton
Review current methods for building PSF-matching kernels for the purposes of image subtraction or coaddition. Compare Gauss-Hermite polynomials vs. delta-function basis functions. Delta-functions are more versatile, but due to its many degrees of freedom, the basis tends to over fit the problem (noisy kernels, large variance). New technique to regularize the delta-function kernel solutions: able to create general kernel solutions that represent the intrinsic shape of the PSF-matching kernel with only one degree of freedom, the strength of the regularization lambda. Role of lambda: effectively to exchange variance in the resulting difference image with variance in the kernel itself.
1202.2932
The origin of dust in galaxies revisited: the mechanism determining dust content
Inoue
Cosmic dust: to get solar neighborhood values, there must be dust mass growth by material accretion in molecular clouds (if dust destruction by SNe is as theory says). Dust content is independent of the uncertainty of the stellar dust yield after the growth activation.
1202.2933
Large-angle non-Gaussianity in simulated high-resolution CMB maps
Bernui, Reboucas, Teixeira
Perform non-G analysis of CMB temperature maps of the local type.
1202.2969
CMB as a possible new tool to study the dark baryons in galaxies
De Paolis, et al
Detecting "dark baryons" in CMB signature around M31: Detect temperature asymmetry in the M31 halo along the rotation direction, up to about 120 kpc.
* no figures, doesn't seem quantitative in terms of the amount of baryons (yet).
1202.2970
Testing a DBI model for the unification of DM and DE with gamma-ray bursts
Montiel, Breton
* nothing is explained well anywhere in this paper/abstract.
1202.2972
COLD GASS, an IRAM Legacy survey of molecular gas in massive galaxies: III. Comparison with semi-analytic models of galaxy formation
Kaufmann, Li, Fu, Saintonge, Catinella, Tacconi, Kramer, Genzel, Moran, Schiminovich
Compare SAM which track the evolution of radial profiles of atomic and molecular gas in galaxies, and compare with gas fraction scaling relation from COLD GASS observations. For disk galaxies, model does not reproduce the tight relation between stellar surface density and bulge-to-disk ratio. For the "quenched" population w/o detectable cold gas: in the model, gas cooling shuts down for all haloes above 1e12 Msun; but observed data show quenching is independent of stellar mass [that's because there are other factors that quench, like small galaxies falling into a larger cluster halo!]. Instead, (observation show that) there are clear thresholds in bulge-to-disk ratio and in stellar surface density that demarcate the location of quenched galaxies. Propose: processes associated with bulge formation play a key role in depleting the neutral gas in galaxies, and that further gas accretion is suppressed following the formation of the bulge, even in dark matter haloes of low mass.
1202.3005
A new MC generator for UHECRs from the local and distance universe
Dolag, Erdmann, Müller, Walz, Winchen
Three-step MC technique for simulating UHECRs: (1) For distant sources, apply commonly accepted parameterizations. (2) For local sources, use forward tracking through realistic matter distributions and B-fields resulting from explicit simulations of LSS. (3) Generate probability maps from (1) and (2) to observe a particle with a given energy from a discrete direction. Deflections in galactic field: transform by matrices "from backtracking of antiparticles through field parameterizations". [?] Based on the combined probability maps, MC production of individual UHECR data is compared to UHECR measurements. MC can both constrain parameter space of underlying source and B-field models, as well as optimize the analysis techniques in UHECR measurements.
1202.2889
Cosmological parameters constraints from galaxy cluster mass function measurements in combination with other cosmological data
Burenin, Vikhlinin
Cosmo parameter constraints obtained from the combination of galaxy cluster mass function measurements with new data: WMAP, SPT, H0, BAO and SNIa. New constraints on total neutrino mass and effective number of neutrino species are obtained. In models with free number of massive neutrinos, the constraints on these parameters are notably less strong, and all considered cosmological data are consistent with non-zero total neutrino mass Sigma m_nu~0.4 eV and larger than standard effective number of neutrino species, N_eff ~ 4. These constraints are compared to the results of neutrino oscillations searches at short baselines. The updated DE EoS parameters constraints are presented. Show that taking in account systematic uncertainties, current cluster mass function data provide similarly powerful constraints on DE EoS, as compared to the constraints from SNIa observations.
1202.2897
Internal stellar kinematics of M32 from the SPLASH survey: Dark halo constraints and the formation of compact elliptical galaxies
Howley, ... Geha, ... Kirby, et al
Imply that, in shaping of cE (compact elliptical, like M32), tidal stripping may not be as significant, from the kinematics of M32, measured out to ~1kpc. Rotation curve and velocity dispersion profile measured, statistically removing M31 effects. M32 kinematics are regular and symmetric and do not show obvious sharp gradients; models with constant M/L can fit the data remarkably well. Half a dozen stars are fast moving, but they may not be bound to M32.
1202.2899
Detailed abundances in stars belonging to ultra-faint dwarf spheroidal galaxies
Francois et al
Close UFdSph chemical composition abundance: slightly lower abundance ratio to what is measured in field halo star of the same metallicity. No extreme abundances in Hercules stars found; synthesis of the neutron capture elements Ba and Sr seem to originate from the same nucleosynthetic process in operation during the early stages of the galactic evolution.
1202.2902
Regularization techniques for PSF-Matching kernels. I. Choice of kernel basis
Becker, Homrighausen, Connolly, Genovese, Owen, Bickerton, Lupton
Review current methods for building PSF-matching kernels for the purposes of image subtraction or coaddition. Compare Gauss-Hermite polynomials vs. delta-function basis functions. Delta-functions are more versatile, but due to its many degrees of freedom, the basis tends to over fit the problem (noisy kernels, large variance). New technique to regularize the delta-function kernel solutions: able to create general kernel solutions that represent the intrinsic shape of the PSF-matching kernel with only one degree of freedom, the strength of the regularization lambda. Role of lambda: effectively to exchange variance in the resulting difference image with variance in the kernel itself.
1202.2932
The origin of dust in galaxies revisited: the mechanism determining dust content
Inoue
Cosmic dust: to get solar neighborhood values, there must be dust mass growth by material accretion in molecular clouds (if dust destruction by SNe is as theory says). Dust content is independent of the uncertainty of the stellar dust yield after the growth activation.
1202.2933
Large-angle non-Gaussianity in simulated high-resolution CMB maps
Bernui, Reboucas, Teixeira
Perform non-G analysis of CMB temperature maps of the local type.
1202.2969
CMB as a possible new tool to study the dark baryons in galaxies
De Paolis, et al
Detecting "dark baryons" in CMB signature around M31: Detect temperature asymmetry in the M31 halo along the rotation direction, up to about 120 kpc.
* no figures, doesn't seem quantitative in terms of the amount of baryons (yet).
1202.2970
Testing a DBI model for the unification of DM and DE with gamma-ray bursts
Montiel, Breton
* nothing is explained well anywhere in this paper/abstract.
1202.2972
COLD GASS, an IRAM Legacy survey of molecular gas in massive galaxies: III. Comparison with semi-analytic models of galaxy formation
Kaufmann, Li, Fu, Saintonge, Catinella, Tacconi, Kramer, Genzel, Moran, Schiminovich
Compare SAM which track the evolution of radial profiles of atomic and molecular gas in galaxies, and compare with gas fraction scaling relation from COLD GASS observations. For disk galaxies, model does not reproduce the tight relation between stellar surface density and bulge-to-disk ratio. For the "quenched" population w/o detectable cold gas: in the model, gas cooling shuts down for all haloes above 1e12 Msun; but observed data show quenching is independent of stellar mass [that's because there are other factors that quench, like small galaxies falling into a larger cluster halo!]. Instead, (observation show that) there are clear thresholds in bulge-to-disk ratio and in stellar surface density that demarcate the location of quenched galaxies. Propose: processes associated with bulge formation play a key role in depleting the neutral gas in galaxies, and that further gas accretion is suppressed following the formation of the bulge, even in dark matter haloes of low mass.
1202.3005
A new MC generator for UHECRs from the local and distance universe
Dolag, Erdmann, Müller, Walz, Winchen
Three-step MC technique for simulating UHECRs: (1) For distant sources, apply commonly accepted parameterizations. (2) For local sources, use forward tracking through realistic matter distributions and B-fields resulting from explicit simulations of LSS. (3) Generate probability maps from (1) and (2) to observe a particle with a given energy from a discrete direction. Deflections in galactic field: transform by matrices "from backtracking of antiparticles through field parameterizations". [?] Based on the combined probability maps, MC production of individual UHECR data is compared to UHECR measurements. MC can both constrain parameter space of underlying source and B-field models, as well as optimize the analysis techniques in UHECR measurements.
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