1608.03074
The Venus Hypothesis
Cartwright
Current models indicate that Venus may have been habitable. Complex life may have evolved on the highly irradiated Venus, and transferred to Earth on asteroids. This model files the pattern of pulses of highly developed life appearing, diversifying and going extinct with astonishing rapidity through the Cambrian and Ordovician periods, and also explains the extraordinary genetic variety which appeared over this period.
1608.03169
CMB Lensing beyond the power spectrum: cosmological constraints from the one-point PDF and peak counts
Liu, Hill, Sherwin, Petri, Böhm, Haiman
Unprecedentedly precies CMB data are expected from ongoing and near-future CMB Stage-III and IV surveys, which will yield reconstructed CMB lensing maps with effective resolution approaching several arc minutes. The small-scale CMB lensing fluctuations receive non-negligible contributions from nonlinear structure in the late-time density field. These fluctuations are not fully characterized by traditional 2pt statistics, such as the power spectrum. Here, use N-body ray-tracing simulations of CMB lensing maps to examine two higher-order statistics: the lensing convergence one-point PDF and peak counts. Show that these statistics contain significant information not captured by the 2pt function, and provide specific forecasts for the ongoing Stage-III AdvACT experiment. Considering only the temperature-based reconstruction estimator, forecast 30 sigma (PDF) and 10 sigma (peaks) detentions of these statistics with AdvACT. The simulation pipeline fully accounts for the non-Gaussianity of the lensing reconstruction noise, which is significant and cannot be neglected. Combining the power spectrum PDF, and peak counts for AdvACT will tighten cosmo constraints in the Omega_m-sigma8 plane by ~30%, compared to using the power spectrum alone.
1608.03279
The Pan-STARRS1 distant z>5.6 quasar survey: more than 100 quasars within the first Gyr of the universe
Bañados, et al
Luminous quasars at z>5.6 can be studied in detail with the current generation of telescopes and provide us with unique information on the first gigayear of the universe. Thus far these studies have been statistically limited by the number of quasars known at these redshifts. Such quasars are rare and therefore wide-field surveys are required to identify them and multi wavelength data are needed to separate them efficiently from their main contaminants, the far more numerous cool dwarfs. In this paper, update and extend the selection for z~6 quasars presented in Banados+2014 using the PS1 survey. Present the PS1 distant quasar sample, which currently consists of 124 quasars in 5.6<z<6.7 that satisfy the selection criteria. 77 of these quasars have been discovered with PS1, and 63 of them are newly identified in this paper. Present composite spectra of the PS1 distant quasar sample. This sample spans a factor of ~20 in luminosity and shows a variety of emission line properties. The number of quasars at z>5.6 presented in this work almost double the quasars previously known at these redshifts, marking a transition phase from studies of individual sources to statistical studies of the high-z quasar population, which was impossible with earlier, smaller samples.
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