1202.5033
Polar ring galaxies in the galaxy zoo
Finkelman, Funes, Brosch
Study 16 polar ring galaxies found in SDSS Galaxy Zoo project. These guys look like a "cross", and the rings are faint. The centrals are typically S0, with a polar ring.
1202.5035
Probing the local velocity distribution of WIMP DM with directional detectors
Lee, Peter
Explore directional nuclear-recoil detectors to constrain local velocity distribution of WIMP DM. Directional information combined with recoil-energy spectrum helps break degeneracies in the velocity-distribuiton parameters.
1202.5036
Wave-wriven mass loss in the last year of stellar evolution: setting the stage for the most luminous core-collapse SNe
Quataert, Shiode
During the late stages of stellar evolution in massive stars (C fusion and later), the fusion luminosity in the core of the star exceeds the Eddington luminosity. This can drive vigorous convective motions which in turn excite internal gravity waves. The local energy flux excited by convection is itself well above Eddington during the last few years in the life of the star. An interesting fraction of the energy in gravity waves can convert into sound waves as it tunnel towards the stellar surface. This can unbind up to several Msun of the stellar envelope. This wave-driven mass loss can explain the existence of extremely large stellar mass loss rates just prior to core-collapse, which are inferred via circumstellar interaction in some core-collpase SNe. The stellar parameters (mass, rotation, metallicity, age) susceptible to wave-driven mass loss depends on the precise internal structure of massive stars and the power-spectrum of internal gravity waves excited by stellar convection.
1202.5037
Spatial curvature falsifies eternal inflation
Kleban, Schillo
Negative curvature is consistent with false-vacuum eternal inflation but not with slow-roll eternal inflation, and positive curvature falsifies both. Need Omega_k measurements that do better than 1e-4. (Inflation creates large-scale density perturbations... The low l multipole moments in the CMB temperature map predict the value of the measured Omega_k. [??? I guess inflation methods give different large-scale fluctuations??? no, that doesn't sound right....]
1202.5079
A Y-band look of the sky with 1-m class telescopes
Choi, Im, Jeon, Ibrahimov
Constrain the bright end of the galaxy and stellar number counts in Y-band. Also test the high-z (z>6) quasar selection via i-z-Y color diagram, which is found to be effective.
1202.5090
Quantifying the biases of spectroscopically selected gravitational lenses
Arneson, Brownstein, Bolton
For SLACS and BELLS (spectroscopically selected galaxy-scale SL), find (1) no mass axis ratio detection bias of lenses relative to parent galaxies, (2) probably negligible bias toward shallow mass density profiles, (3) A detection bias towards smaller Einstein radius for systems drawn from group and cluster-scale lensing masses, and (4) a lens-modeling bias towards larger velocity dispersions for systems drawn from parent samples with sub-arcsecond mean Einstein radii. Completeness is quite uniform in the region, up to a sharp drop in the region of large Einstein radius and steep mass density profile, and hence that such surveys are ideally suited to the study of massive field galaxies.
* Holographic principle: A property of quantum gravity and string theories which states that the description of a volume of space can be thought of as encoded on a boundary of the region, preferably a light-like boundary like a gravitational horizon. String theory admits a lower dimensional description in which gravity emerges from it in what would be called a holographic way. In a more speculative sense, the theory suggests that the entire universe can be seen as a 2-d information structure "painted" on the cosmological horizon, such that the 3d that we observe are only an effective description at macroscopic scales and at low energies. Inspired by BH thermodynamics.
1202.5163
Generalized holographic dark energy
Zhang, Li, Li, Wang, Zhang
In the original holographic dark energy model, DE is proposed to be rho = 3 c^2 M^2_pl L^-2, where ci is a dimensionless constant characterizing the properties of the HDE. Generalize HDE so that c = c(z). This fits better to data.
1202.5178
CMB lensing and giant rings
Rathaus, Itzhaki
Study the CMB lensing signature of pre-inflationary particle (PIP), assuming it is responsible for the giant ring anomaly found in WMAP. Difficult to measure, but if PIP is also responsible for the bulk flow that happens to point roughly at the same direction as the giant rings, then the CMB lensing signal to noise ratio is >2sigma.
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