Day 653

Sunday.

1401.7017
Calcium-rich gap transients: solving the Calcium Conundrum in the intracluster medium
Mulchaey, Kasliwal, Kollmeier

The abundance of Ca in ICM is higher than expected using models for core-collapse and Type Ia SNe alone, but can be alleviated by including a contribution from the recently discovered subclass of SNe known as Ca-rich gap transients.  These SNe type seem to be associated with intracluster stars, and not individual galaxies.

1401.7022
Inflationary freedom and cosmological neutrino constraints
de Putter, Linder, Mishra

Massive relic neutrinos affect the expansion history of the universe and lead to a suppression of matter clustering on scales smaller than the associated free streaming length, but the resulting effect on cosmological perturbations is relative to the primordial PS of density perturbations from inflation, so freedom in the primordial PS affects neutrino mass constraints.  Using measurements of the CMB, the galaxy PS and the Hubble constant, constrain neutrino mass and number of species for a model independent primordial PS.  Describing the primordial PS by a 20-node spline, find that the neutrino mass upper limit is a factor 3 weaker than when a power law form is imposed, if only CMB data are used.  The primordial PS itself is constrained to better than 10% in the wave vector range k~0.01-0.25 Mpc^-2.  Galaxy clustering data and a determination of the Hubble constant play a key role in reining in the effects of inflationary freedom on neutrino constraints.  The inclusion of both eliminates the inflationary freedom degradation of the neutrino mass bound, giving for the sum of neutrino masses Sum m_nu< 0.18 eV (at 95% CL, Planck+BOSS+H0), approximately independent of the assumed primordial PS model.  When allowing for a free effective number of species, N_eff, the joint constraints on Sum m_nu and N_eff are loosened by a factor 1.7 when the power law form of the primordial PS is abandoned in favor of the spline parameterization.

1401.7051
A CMB lensing-galaxy intrinsic alignment contaminant to gravitational lensing cross-correlated probes of the universe and a proposal for calibration
Troxel, Ishak

Introduce a cross-correlation term between CMB lensing and IA (phi I).  This effect acts as a contaminant to the cross-correlation between CMB lensing and galaxy lensing.  The latter cross-correlation has recently been detected for the first time, and measurements will greatly improve as the area of overlap between galaxy and CMB surveys increases and measurement of the CMB polarization become more significant.  This will constitute a powerful probe for studying the structure and evolution of the universe.  The magnitude of the phi I term is found to be about 15% of the pure CMB lensing-galaxy lensing component and acts to reduce the magnitude of its measured spectrum.  This offset in the spectrum will strongly impact its use for precision cosmological study if left unmitigated.  Also propose a method to calibrate this phi I contamination through use of a scaling relation that allows one to reduce the impact of phi I by a factor of 20 or more in all redshift bins, which would reduce its magnitude down to detection limits in almost all cases.  This will allow the full use of this probe for precision cosmology.

1401.7221
Tides, planetary companions, and habitability: Habitability in the habitable zone of low-mass stars
Van Laerhoven, Barnes, Greenberg

Earth-scale planets in the classical HZ are more likely to be habitable if they possess active geophysics [because O, N, S, P, gets replenished from the planet itself into the presumably existing liquid water; rotating Fe core in the molten earth generates B-fields that deflect harmful CRs; and stabilizes the temperature by C recycling into the crust].  Without a constant internal energy source, planets cool as they age, eventually terminating tectonic activity and rendering the planet sterile to life [in Earth, at least some of the heat is maintained from radioactive decay of elements in the molten core, though].  However, for planets orbiting low-mass stars, the presence of an outer companion could generate enough tidal heat in the HZ planet to prevent such cooling.  The range of mass and orbital parameters for the companion that give adequate long-term heating of the inner HZ planet, while avoiding very early total desiccation, is probably substantial.  Locate the ideal location for the outer of a pair of planets, under the assumption that they inner planet has the same incident flux as Earth, orbiting example stars: a generic late M dwarf (Teff=2670K) and the M9V/L0 dwarf DEN1048.  Thus discoveries of Earth-scale planets in the HZ zone of old small stars should be followed by searches for outer companion planets that might be essential for current habitability.