Wednesday. Saw Uros & Petra's house yesterday. They bought all the furnitures and decorations themselves (sounds like Petra mostly did it), while in Europe, and had it shipped over. It was beautiful. Nika and Sebastian, their kids, were very cute too. ... Must generate NFW fit today, but astro-ph first. Then read Melchior paper, Eric Huff's, and maybe Bhuv's.
* plasma wakefield acceleration: technique for accelerating charged particles (e-, e+, ions) using E-field associated with electron plasma wave. Wave created either using e- pulses, or through the passage of very brief laser pulses (laser plasma acceleration). This technique can build high performance particle accelerators of much smaller size than conventional devices, at the expense of coherency. LBL has an experimental device that accelerates electrons to 1GeV over about 3.3 cm; SLAC conventional accelerator requires 64m to reach the same energy. The technology could replace many of the traditional RF accelerators currently found in hospitals and research facilities. Basic concept: Plasma is a fluid of e- and ions, but ions are much heavier. Can accelerate an injected charged ion with a "plasma with an external E- or EB field applied, such that the plasma electron will spatially separate from the massive ions, creating a charge imbalance, and hence generating a strong field". The plasma medium acts as the most efficient transformer of the transverse field of an EM wave into longitudinal fields of a plasma wave. In existing accelerator technology, various appropriately designed materials are used to convert from transverse propagating extremely intense fields in to longitudinal fields that the particles can get a kick from. Two approaches: standing wave structures (resonant cavities) or traveling-wave structures (disc-loaded waveguides). Limitation of materials interacting with higher and higher fields: eventually they get destroyed through ionization and breakdown (which forms a plasma). Most non-DM universe is plasma; such plasma-processes are common in astrophysical plasma.
1204.6117
Scatter and bias in weak lensing selected clusters
Hamana, Oguri, Shirasaki, Sato
Scatter and bias in WL selected clusters, employing both analytic models of DM haloes and numerical mock data of WL cluster surveys; effects of diversity of DM distributions within clusters. Dependence of the halo shape on the peak heights, find rms scatter caused by halo diversity scales linearly with the peak heights (proportionality factor 0.1-0.2). Noise originates from the halo shape is comparable to the source galaxy shape noise and the cosmic shear noise. Find significant halo orientation bias (WL selected clusters on average have their major axis aligned with the LoS direction, and this bias is stronger for higher SN ratio peaks. Compute orientation bias using analytic triaxial halo model; results consistent with ray-tracing results. Develop prescription to analytically compute the number count of WL peaks, taking into account all the main sources of scatters in peak heights. Find: improved analytic predictions agree well with the simulation results for high peaks of SN>5. Also compare the expected number count with the WL analysis results for 4 sq deg of Subaru/Suprime-cam observations and find good agreement.
1204.6122
VLTI/AMBER observations of the Seyfert nucleus of NGC 3783
Weigelt, .. Kishimoto, et al
Tori surrounding accretion disks of AGNs play a fundamental role in the unification scheme of AGNs. IR long-baseline interferometry can study the dust distribution in the inner tori. Find ring-fit torus radius of 0.16 pm 0.05 pc. Model near and mid IR visibilities and the SED with a temperature/density-gradient model including an additional inner hot 1400K ring component.
1204.6197
SDSS quasars in the WISE preliminary data release and quasar candidate selection with the optical/infrared colors
Wu, Hao, Jia, Zhang, Peng
Catalog of 37842 quasars in SDSS DR7 that have counterparts within 6" of the WISE preliminary data release. WISE detection rate is 86.7%, but drops to <50% when quasar magnitude is fainter than i=20.5. Estimate photo-z of SDSS-WISE quasars, increase reliability with IR data (very roughly). Criteria from color-color diagrams.
1204.6212
Ionised gas abundances in barred spiral galaxies
Florido, Perez, Zurita, Sanchez-Blazquez
Bar/disk nebular metallicities are higher than the central ones might indicate that the gas could be accreted via cooling flows instead of radial accretion from gas sitting in the outer parts of the disk.
1204.6223
Background, foreground and nearby matter influence on strong gravitational lenses
Jaroszynski, Kostrzewa-Rutkowska
SL by non-singular finite isothermal ellipsoids (LoS and nearby matter included). Compare: (i) full approach with all matter inhomogeneities, (ii) single plane approach (neglect foreground and background but include neighbors), (iii) single lens approach. Simulate SL configurations with a point source at the same redshift but in different locations inside the region surrounded by caustics. For every simulation, attempt to fit a single isothermal ellipsoid or single isothermal ellipsoid with external shear. Fits are rejected in (i), less rejection for single plane approach. Matter close to the lens and matter along the rays do have important influence on lens modeling. Estimate the typical value of external shear.
1204.6301
A comparative study of local galaxy clusters: I. derived X-ray observables
Rozo, Rykoff, Bartlett, Evrard
Examine systematic differences in the derived X-ray properties of galaxy clusters in 3 different groups (Vikhlinin+ 2009a, Mantz+2010b, and Planck Collab 2011b). 16 to 28 clusters in common. Find systematic differences in most reported properties, including the total cluster mass M500, up to 45% pm 5% difference in cluster mass between Planck and Mantz for z>0.13 clusters (over 16 clusters). Account for aperture differences, and find good agreement in gas mass estimates between the different groups. The soft-band X-ray luminosity LX, core-excised spectroscopic temperature TX and gas thermal energy YX display mean differences at the 5-15% level. The low and high z galaxy cluster (z=0.13 threshold) appear to be systematically different: the YSZ/YZ ratio differ.
1204.6292
A comparative study of local galaxy clusters: II: X-ray and SZ scaling relations
Rozo, Evrard, Rykoff, Bartlett
Compare cluster scaling relations published for X-ray and SZ samples. Tensions due to 2 factors: (i) systematic differences in the x-ray cluster observables used to drive the scaling relations, and (ii) uncertainty in the modeling of how the gas mass of galaxy clusters scales with total mass. All scaling relations are in agreement after accounting for these two effects. Describe a multivariate scaling model that enables a fully self-consistent treatment of multiple observational catalogs in the presence of property covariance, and apply this formalism when interpreting published results. The corrections due to scatter and observable covariance can be significant. Example: The predicted YSZ-LX scaling relation differs from the derived "plug in" method by ~25%. Test the mass normalization for each of the X-ray data sets by applying a space density consistence test: compare the observed REFLEX luminosity function to expectations from published LX-M relations convolved with the mass function for a WMAP7 flat LCDM model. Not all of the LX-M scaling relations considered satisfy this consistency test.
1204.6305
Closing the loop: a self-consistent model of optical, X-ray, and SZ scaling relations for clusters of galaxies
Demonstrate the optical data from SDSS, X-ray from ROSAT and Chandra, and SZ from Planck, can be modeled in a fully self-consistent manner. Account for systematic errors and allowing for property covariance, find that scaling relations derived from optical and X-ray selected cluster are consistent with one another. These clusters scaling relations satisfy several non-trivial spatial abundance constraints and closure relations. Good agreement between optical and x-ray samples--combine the two and derive a joint set of LX-M and YSZ-M relations. Best fit YSZ-M relation is in good agreement with the observed amplitude of the thermal SZ power spectrum for a WMAP7 cosmology, and is consistent with the masses for the two CLASH galaxy cluster published thus far. Predict the halo masses of the remaining z<=0.4 CLASH clusters, and use scaling relations to compare results with a variety of X-ray and WL cluster masses from the literature.
1204.6312
Electron accelerations at high mach number shocks: two-dimensional particle-in-cell simulations in various parameter regimes
Matsumoto, Amano, Hoshino
2d EM particle-in-cell simulations of e- accelerations at high Mach number collision-less shocks. Electrons are effectively accelerated at a super-high Mach number shock at certain numbers. The e- shock surfing acceleration is an effective mechanism for accelerating the particles toward the relativistic regime even in 2 dimensions with large mass ratio. ... e- shock surfing acceleration is an effective mechanism for producing relativistic particles in extremely-high Mach number shocks in SNe remnants, provided that the upstream e- temperature is reasonably low.
(*) 1204.6316
Warm gas in the Virgo cluster: I. distribution of Lya absorbers
Yoon, Putman, Thom, Chen, Bryan
Present warm gas (T=1e4-5K) distribution across galaxy cluster; use BG QSO to Virgo Cluster. Detect 25 Lya absorbers in the Virgo range toward 9/12 QSO sight lines with impact parameter range of 0.25-1.15 Mpc (0.25 to 1 Rvir). Find: 1) warm gas is predominantly in the outskirts of the cluster and avoids the X-ray detected hot ICM; Lya absorption strength increases with impact parameter. 2) Lya absorbing warm gas traces cold HI emitting gas in the substructures of the Virgo Cluster. 3) Including surrounding substructures, the warm gas covering fraction is in an agreement with cosmological simulations. Speculate that observed warm gas is part of large-scale gas flows feeding the cluster ICM and galaxies.
1204.6318
Effects and detectability of quasi-single field inflation in the large-scale structure and cosmic microwave background
Sefusatti, Fergusson, Chen, Shellard
Quasi-single-field inflation predicts a peculiar momentum dependence in the squeezed limit of the primordial bispectrum which smoothly interpolates between the local and equilateral models; dependence directly related to the mass of the isocurvatons in the theory which is determined by the supersymmetry. If non-zero primordial bispectrum found, then additional constraints from the squeezed limit becomes important. Effects of these non-Gaussian initial conditions on large-scale structure and CMB, esp to galaxy power spectrum at large scales. ...
1204.6324
Prospects for constraining the shape of non-Gaussianity with the scale-dependent bias
Norena, Verde, Barenboim, Bosch
Find: proposed LSS surveys (stage IV equivalents) have the potential to distinguish among the squeezed limit behavior of different bispectrum shapes for a wide range of fiducial model parameters. Thus the halo bias can help discriminate between different models of inflation.
1204.6359
Hubble constant, lensing, and time delay in TeVeS
Tian, Ko, Chiu
Time delay in SL systems can determine H0. We now have more time delay observations. Use TeVeS instead of DM.
1204.6489
Strong scale dependent bispectrum in the Starobinsky model of inflation
Arroja, Sasaki
* Hey, Uncle. Gramps.
Compute analytically the dominant contribution to the tree-level bispectrum in the Starobinsky model of inflation. ...
1204.6586
UltraVISTA: a new ultra-deep near-infrared survey in COSMOS
McCracken, ...Mellier, et al
DR1 of UltraVISTA NIR imaging survey of the COSMOS field (YJHKs bands); key goals described [but not in the abstract!].
(*) 1204.6630
Application of GPUs for the calculation of two point correlation functions in cosmology
Ponce, et al
Explore te advantages and drawbacks of GPUs in the calculation of standard 2pt correlation function--useful for the analysis of LSS. GPUs offer a 100-fold increase in speed wrt a single CPU w/o significant deviation in the results. MPI version developed for comparison. Code implementation discussed.
1204.6666
Complexity reduction of astrochemical networks
Grassi, et al
New computational scheme aimed at reducing the complexity of the chemical networks in astrophysical models.
1204.6716
Fully digital: policy and process implications for the AAS
Biemesderfer
Migration of mechanical aspects of journal publishing to digital means. AAS thinks that bringing publish program to the point of being fully digital by establishing procedures and policies that regard the digital objects of publication. Electronic journals as databases of digital articles. Must develop practices that are consistent with the realities of article at a time publication online [???]. Want publishers to evolve fully digital.
1204.6739
Cosmology with the lights off: standard sirens in the Einstein telescope era
Taylor, Gair
Constraining cosmology using GW observations of NS binaries with ET, exploiting the narrowness of the NS mass function. Double NS binaries are expected to be one of the first sources detected after "first-light" of Advanced LIGO, and expected to be detected at a rate of a few tens per year in the advanced era. [!!] Combine measured source redshift distributions with GW-network distance determinations will permit not only the precision measurement of BG cosmological parameters, but will provide insight into the astrophysical properties of these DNS systems.
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