Day 109

Monday.  Forgot my phone at home!  No phone calls today, I guess.


1110.3045
Clustering and redshift-space distortions in interacting DE cosmologies
Maruli, Baldi, Moscardini


LSS in coupled dark energy (cDE) cosmologies.  Use CoDECS simulations, public halo catalogs, estimate clustering and bias functions of CDM haloes, both in real- and redshift-space.  Effects of cDE on geometric and dynamic redshift-space distortions, quantifying the difference with LCDM.  At z~0, spatial properties of CDM haloes in cDE models appear very similar to LCDM (after normalizing to CMB data).  At higher z, cDE produces scale-dependent suppression of halo clustering and bias function.  Effect depends strongly on the coupling strength; not degenerate with sigma8 at scales r<5-10 Mpc/h.  Find cDE strongly affects both the linear distortion parameter, beta, and pairwise peculiar velocity dispersion, sigma12.  Models considered in this work found to be all in agreement with presently available observational data--next generation of galaxy surveys will be able to put strong constraints on the level of coupling between DE and CDM exploiting the shape of z-space clustering anisotropies.


1110.3050
Non-Gaussianity from step features in the inflationary potential
Adshead, Dvorkin, Hu, Lim


Analytic solutions for the power spectrum and bispectrum of curvature fluctuations produced by a step features in the inflation potential (valid in the limit that the step is short and sharp.  Bispectrum is strongly scale dependent; its effective non-linearty attains a large oscillatory amplitude.  Perturbations to the curvature power spectrum remain a small component on top of the usual spectrum of fluctuations generated by slow roll.  Utilize analytic solutions to assess the observability of the predicted non-Gaussian signatures and show that, if present, only very shapr steps on scales larger than ~2Gpc are likely to be able to be detected by Planck.  Such features are not only consistent with WMAP7 data, but can also improve its likelihood by 2 Delta ln L ~12 for two extra parameters, the step location and height.  If this improvement were due to a slow roll violating step considered here, a bispectrum or corresponding polarization power spectrum detections would provide definitive checks as to its primordial origin.


1110.3193
Euclid definition study report
Editorial team: Laureijs, ... Hoekstra, Kitching, Mellier, Percival, Rhodes, ... et al.


Euclid:  space-based survey mission from ESA designed to understand the origin of the Universe's accelerating expansion.  Probe nature of DE, DM and gravity, by probing signatures on geometry of the universe and the cosmic history of structure formation.  Two independent primary cosmological probes: WL and BAO.  1.2m Korsch telescope for large FOV; two instruments with a common FOV or 0.54 deg^2: visual imager (VIS) and near infrared instrument (NISP) which contains a slitles spectrometer and three band photometer.  Euclid wide survey will cover 15k deg^2 of the sky, copmlemented by two 20 deg^2 deep fields.  For WL, Euclid measures shapes of 30-40 resolved galaxies per arcmin^2 in one broad visible R+I+Z band (550-920 nm).  The photometric redshifts for these galaxies reach a precision of dz/(1+z) = 0.001.  The slitless spectrometer, with spectral resolution ~250, predominantly detects Ha emission line galaxies.  Euclid is a Medium Class mission of the ESA cosmic vision 2015-2025 programme, with a foreseen launch date in 2019.  This report (aka Euclid Red Book) describes the outcome of the Phase A study.


1110.3230
First evidence of pep solar neutrinos by direct detection in Borexino
Borexino Collaboration


* pep reaction: Deuterium produced by this rare reaction: H + e- + H => 2D + nu_e.  Frequency ratio of the pep reaction versus the pp reaction is 1:400.  The neutrinos release by the pep reaction are far more energetic (0.42MeV vs. 1.44 MeV)
* pp reaction: H + H => 2D + (e+) + nu_e


Solar neutrinos in the 1.0-1.5 MeV energy range observed (for the first time).  Rate of pep solar neutrino interactions measured to be 3.1pm0.9 counts/(day x 100 ton), provide constraint on the CNO solar neutrino interaction rate of <7.9 counts/(day 100ton) (95% CL).  Absence of solar neutrino signal disfavored at 99.97% CL, while absence of pep signal is disfavored at 98% CL in the 1-2 MeV region.  Novel data analysis techniques for the rejection of cosmogenic 11C (dominant BG in the 1-2 MeV region).  Assuming MSW-LMA solution [??] to solar neutrino oscillations, these values correspond to solar neutrino fluxes of (1.6 pm 0.3)e8 /cm2/s and 7.7e8 /cm2/s, respectively [??], in agreement with the Standard Solar Model.  Results represent the first measurement of the pep neutrino flux and the strongest constraint of the CNO solar neutrino flux to date.