Sunday. Couldn't finish everything yesterday. Try to finish it today? (seems impossible) At least get the MNRAS referee review response written and sent out...
1110.4389
A ray-tracing algorithm for spinning compact object spacetimes with arbitrary quadrupole moments. II. Neutron stars
Baubock, Psaltis, Ozel, Johannsen
A moderately spinning neutron star acquires an oblate shape and a spacetime with a significant quadrupole moment; affects surface area for an observer at infinity, as well as the lightcurve arising from a hot spot on its surface. Develop a ray-tracing algorithm to calculate the apparent surface areas of moderately spinning neutron stars making use of the Hartle-Thorne metric; allows calculation of NS observables that only depends only on its macroscopic properties (and not on details of its equation of state. Calculate changes in the apparent surface area which could play a role in measurements of NS radii (and hence in constraining their equation of state). Find: for NS with r~10 km, corrections to the Schwarzschild spacetime case the apparent surface area to increase with spin frequency. In contrast, for neutron stars with radii ~15 km, the oblateness of star dominates the spacetime corrections and causes the apparent surface area to decrease with increasing spin frequency. In all cases, the change in the apparent geometric surface area for the range of observed spin frequencies is <5% and hence only a small source of error in the measurement of neutron star radii.
* I like the way this abstract was constructed.
1110.4402
Clustering of primordial black holes. II. Evolution of bound systems
Chisholm
Primordial black holes (PBHs) are more clustered than the underlying density field; have shown constraints on prospects of PBH dark matter; show formation of bound systems of PBHs before Hawking evaporation.
* Hawking radiation: solar mass BH has 60 nK, lunar mass BH has 2.7K (same as CMB today), and primordial black holes would emit more Hawking (BB) radiation than they absorb, and thereby lose mass.
1110.4408
Metallicity properties of zCOSMOS galaxies at 0.2<z<0.8
Cresci, Mannucci, Sommariva, Maiolino, Marconi, Brusa
Dependence of metallicity on stellar mass and SFR (the Fundamental Metallicity Relation) at z<0.46; extend this relation to higher redshift, 0.49<z<0.8 where the R23 metallicity index can be measured in data. Find no evidence for evolution, metallicity scatter around the relation of about 0.16 dex. Result confirms (at high significance) the absence of evolution of the FMR during the last half of cosmic history.
1110.4413
Radial migration in disk galaxies I: Transient spiral structure and dynamics
Roskar, Debattista, Quinn, Wadsley
Seek to understand the origin of radial migration [of stars] in spiral galaxies, by analyzing the structure and evolution of an idealized, isolated galactic disk. Characterze the time-evolution of properties of sprials that spontaneously form in the disk; single spirals unlikely, but number of transient patterns can coexist. At any given time the disk favors patterns of certain patter speeds. The corotation scattering mechanism by Selwood and Binney (2002) is responsible for the largest angular momentum changes in the simulations.
1110.4422
High resolution XMM-Newton Spectroscopy of the cooling flow cluster A3112
Bulbul, Smith, Foster, COttam, Loewenstein, Mushotzky, Shafer
Fe and Si abundance gradients show significant increase towards the center of the cluster, while oxygen abundance profile is centrally peaked but with shallower distribution than Fe. X-ray mass modeling based on temperature and deprojected density distributions of ICM. Total mass of A3112 obeys the M-T scaling relation of massive clusters at R500. The gas mass fraction at R500 is also consistent with WMAP7. Comparisons of line fluxes and flux limits on the Fe XVII and XVIII lines indicate there is no spectral evidence for cooler gas with temperature below 1keV in the central <38" (~52 kpc) region. [no cool core?] Find upper limit to turbulent motions in the compact core; energy contribution of turbulence to total energy is <5%. Upper limit consistent with recent high-resolution simulation of relaxed galaxy clusters.
* what is the temperature of the cool core of cool-core clusters?
1110.4431
A grand rotation curve and DM halo in the MW
Sofue-san
* this one is not clear *from which data* the numbers were constructed from. Observations? Speculations?
Rotation curve from Galactic center to 1Mpc constructed, with bulge, disk, and halo components. M_bulge=1.7e10 Msun, a_bulge=0.5kpc, M_disk=3e10Msun, a_disk=3kpc. Dark halo fitted by NFW, where the fit gave r_c=16kpc and rho_0=7e-3 Msun pc^-3. Local DM density near the Sun at R_0=8kpc is estimated to be rho_0_@sun=6e-2Msun pc^-3 = 0.26 GeV cm^-3. Total mass inside the gravitational boundary of the galaxy at R~385 kpc (halfway to M31) is estimated to be M_h~1e12 Msun. Stellar baryon fraction of 5%. Deduce baryons in the form of gas are filling the DH with with a temperature of 1e6K and emission measure 1e-4 pc cm^2. Such hot halo gas may share a small fraction of the observed X-ray BG emission.
* better if they calculated what they estimate the x-ray fraction to be.
1110.4465
The chemical evolution of the galactic bulge seen through micro-lensing events
Feltzing, Bensby, Melendez, Aden, Asplund, Gould Johnson, Lucatello, Gal-Yam
From microlensing events, obtain spectra of high resolution and moderately high S/N of dwarf stars in the galactic bulge.
* can't tell if they're talking about a possibility, or if they have the measurements. I guess they're trying for these measurements.
1110.4463
Near-IR polarimetry around 30 Doradus:
* 30 Doradus == Tarantula nebula == NGC2070. Resides in LMC. Most active starburst region (and largest at diameter of ~200pc) known in the local group. At leading edge of the LMC (ram pressure stripping, compression of ISM at maximum). Center contains compact star cluster R136 (35 ly diameter). Mass of cluster ~4.5e5 M_sun, likely to become a globular cluster in the future. Also contains an older star cluster (Hodge 301) of age 20-25 Myr. Supernova 1987A occurred in the outskirts of the Tarantula nebula.
the abstract itself wasn't too interesting (to me).
1110.4557
The First observations of low-z DLA systems with COS: Chemical abundances and affliliated galaxies
Battisti, et al
DLA systems always have lower metallicity than sub-DLA systems at all z, but do show increase in metallicity over time. DLA show large range in metallicities (-1.1<[Z/H]<0.31), similarly found at high z. DLAs have variety of origins, and low-z studies are crucial for understanding absorber-galaxy connections.
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