1205.2395
Type 1b/c supernovae with and without gamma-ray bursts
Modjaz
Connection between long GRBs and SNe Ib/c from stripped stars has been well-established, one outstanding question is what conditions and factors lead to each kind of explosion in massive stripped stars---so, compare SNe Ib/c with and without GRBs. 70 SNe of types IIb, Ib, Ic and Ic-bl (x3 previously known) of well-observed Stripped SNe. Demonstrate that a meta-analysis of the 3 published SN Ib/c metallicity data sets indicates that SNe Ic erupt from more metal-rich environments than SNe Ib, while SNe Ic-bl with GRBs still prefer more metal-poor sites than those without GRBs.
1205.2422
Spatial urvature and cosmological tests of general relativity
Dossett, Ishak
Study the effect of curvature on constraints on parameters used to test General Relativity (GR) at cosmological scales (MG parameters). Constraints are (of course) weakened. Assumption of a spatially flat model on a (spatially) curved universe causes an artificial shift (bias) in the constraints of MG parameters, in some cases causing an apparent deviation from GR . When using future high precision data to perform tests, spatial curvature must be included in the parameter analysis along with other ore parameters and the MG parameters.
1205.2429
The habitable zone and extreme planetary orbits
Kane, Gelino
Describe the development of the Habitable Zone concept, application to the Solar System, and to exoplanetary systems. Apply to extreme eccentric orbits, and show how they may still retain life bearing properties depending upon the percentage of the total orbit which is spent within the Habitable Zone.
1205.2522
Astrophysical objects observed by the MESSENGER X-ray spectrometer during Mecury flybys
Bannister, Fraser, Lindsay Martindale, Talboys
Find: 2 X-ray peaks attributed in earlier work to the detection of supra thermal electrons from the Mercury magnetosphere are likely to contain a significant number of events that are of astrophysical origin. ... [??]
1205.2533
On galaxies and homology
Novak, Jonsson, Primack, Cox, Dekel
"A set of galaxies is homologous if they are the same in all respects up to a set of 3 scaling constants, which may differ from one galaxy to the next." Find: a set of hydrodynamic simulated galaxy merger remnants is significantly closer to homologous when the dimensional length constant is taken to be the radius containing equal amounts of DM and baryonic matter, rather than the usual baryonic half-mass radius. Once the correct dimensional scaling constants are used, the stellar velocity dispersion anisotropy is essentially the sole source of the variation in the kinematic structure of these simulated merger remnants.
1205.2537
Cosmic microwave and infrared backgrounds cross-correlation for ISW detection
Ilic
As the title says: The S/N can be up to 6 to 7 sigma in the ideal case (depending on the frequency). Realistically, 2-5 sigma.
1205.2693
The velocity dispersion and mass function of the outer halo globular cluster Palomar 4
Frank, Hilker, Baumgardt, Cote, Grebel, Haghi, Küpper, Djorgovski
...and the cluster's surface brightness profile based on WFPC2; broad-band imaging with low-res spectra at Keck II. Mean cluster velocity of 72.55pm0.22 km/s, velocity dispersion of 0.87pm0.18 km/s. The global mass function of the cluster, in the mass range 0.55<m<0.85 Msun, is shallower than a Kroupa mass function and the clutter is significantly depleted in low-mass stars in its center compared to its outskirts. Relaxation time of Pal4 is order Hubble time; so there must be mass segregation in this cluster. Total cluster mass of 29.8k Msun. Consistent with Newtonian, below prediction of MOND. Dynamics of star clusters in the outer Galactic halo can hardly be explained by MOND.
1205.2694
Shaping the galaxy stellar mass function with supernova- and AGN-driven winds
Puchwein, Springel
Show that an energy-driven outflow model in which the wind velocity decreases and the wind mass loading increases in low-mass galaxies, as suggested by observations, can produce a good match to the low-mass end of the observed galaxy stellar mass function. High-mass end can be recovered simultaneously if AGN feedback and correction for diffuse stellar light missed in observations are included. Good agreement with z=1 and z=2 stellar mass function, and observed z evolution of cosmic SFR density. Suggests that the mass flux in the real galactic winds should strongly increase towards low-mass galaxies. Without this assumption, an overproduction of galaxies at the faint-end of the galaxy luminosity function seems inevitable in these models. [Tsaliakovich & Hirata paper relevant here?]
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