Day 590

Sunday.  Monday.

1402.0037
Formation of the Moon: a new mechanism
Gupta

Understanding the Moon's formation mechanism is necessary for studying not only the Moon itself, but also the evolution, formation, habitability, and structure of other planets and the moons in the Solar system and in extrasolar planetary systems.  In this paper, suggest a mechanism of the Moon formation: form at the time of planet formation in a parallel and simultaneous process, and the new moons cannot form in a grown up Solar system.  [This is different from the current theory of Moon formation…]

1402.0075
Galaxy luminosity function and its cosmological evolution: testing a new feedback model depending n galaxy-scale dust opacity
Makiya, Totani, et al

New SAM incorporating a SF law with a feedback depending on the galaxy-scale mean dust opacity and metallicity, motivated by recent observations of SF in nearby galaxies and theoretical considerations.  This new model is used to investigate the effect of such a feedback on shaping the galaxy LF and its evolution.  SF activity is significantly suppressed in dwarf galaxies by the new feedback effect, and the faint-end slope of local LFs can be reproduced with a reasonable strength of SN feedback, which is in contrast to the previous models that require a rather extreme strength of SN feedback.  Model can also reproduce the early appearance of massive galaxy manifested in the bright-end of high z K-band LFs.  Though some of the previous models also succeeded in reproducing this, they assumed a SF law depending on the galaxy-scale dynamical time, which is not supported by observations.  Argue that the feedback depending on dust opacity (or metal column density) is essential, rather than that simply depending on gas column density, to get these results.

1402.0466
Molecular excitations: a new way to detect Dark matter
Va'vra

Possibility that DAMA observes the WIMP via molecular excitations of OH-molecules, left in the NaI(TI) material as an impurity.  Independently of the outcome of this particular investigation, think that the DM shear should be expanded into a domain of detectors sensitive to molecular excitations, and therefore make searches more sensitive.  In this paper, investigate the fused silica material with large content of OH-molecules, which are intentionally loaded into this material to improve the radiation hardness and to reduce the UV sensitivity.  Also looked at a possibility to use simple pure water to detect vibrations of water molecule and conclude that it is worthwhile to pursue further.  Presently, we do not have suitable IR detectors to observe long wavelengths, however, some OH-molecular excitations extend to visible and UV wavelengths, and can be measured by Bialkali photocathodes.  There are many other chemical substances with diatomic molecules, which could be investigated along these lines as well.

1402.3293
Testing the equal-time angular-averaged consistency relation of the gravitational dynamics in N-body simulations
Nishimichi, Valegeas

Test the equal-time consistency relation [?] between the angular-averaged bispectrum and the PS of the matter density field, employing a large suite of cosmological N-body simulations.  This is the lowest-order version of the relations between (ell+n)-point and n-point polyspectra, where one averages over the angles of ell soft modes.  This relation depends on two wave numbers, k' in the soft domain and k in the hard domain [what's a soft and hard domain?].  Show that it holds up to a good accuracy, when k'/k << 1 and k' is in the linear regime, while the hard mode k goes from linear (0.1 h/Mpc) to nonlinear (1.0 h/Mpc) scales.  On scales k<0.4 h/Mpc, conform the relation within a ~5% accuracy, even though the bispectrm can already deviate from leading-order perturbation theory by more than 30 %.  Further show that the relation extends up to NL scales, k~1.0 h/Mpc, within an accuracy of ~10%.

1402.3302
Detection of stacked filament lensing between SDSS luminous red galaxies
Clampitt, Jain, Takada

Search for the lensing signal of massive filaments between 220,000 pairs of LRGs from the SDSS.  Use a nulling technique to remove the contribution of the LRG halos, resulting in a 10 sigma detection of the filament lensing signal.  Compare the measurements with halo model predictions based on a calculation of 3pt halo-halo-mass correlations.  Comparing the "thick" halo model filament to a "thin" string of halos, thick filaments larger than a Mpc in width are clearly preferred by the data.

1402.3394
The connection between galaxy structure and quenching efficiency
Omand, Balogh, Poggianti

From SDSS DR7 with structural measurements from GIM2D, show how the fraction of quiescent galaxies depends on galaxy stellar mass M*, effective radius R_e, fraction of r-band light in the bulge, B/T, and their status as a central or satellite galaxy at 0.01<z<0.2.  For central galaxies, confirm that the quiescent fraction depends not only on stellar mass, but also on R_e.  The dependence is particularly strong as a function of M*/R_e^alpha, with alpha ~ 1.5.  This appears to be driven by a simple dependence on B/T per the mass range 9<log(M*/Msun)<11.5, and is qualitatively similar even if galaxies with B/T>0.3 are excluded. For satellite galaxies, the quiescent fraction is always larger than that of central galaxies, for any combination of M*, R_e and B/T.  The quenching efficiency is not constant, but reaches a maximum of ~0.7 for galaxies with 9<log(M*/Msun)<9.5 and R_e<1 kpc.  This is the same region of parameter space in which the satellite fraction itself reaches its maximum value, suggesting that the transformation from an active central galaxy to a quiescent satellite is associated with a reduction in R_e due to an increase in dominance of a bulge component.