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Dark radiation sterile neutrino candidates after Planck data
Di Valentino, Eleonora; Melchiorri, Alessandro; Mena, Olga
Recent Cosmic Microwave Background (CMB) results from the Planck satellite, combined with previous CMB data and Hubble constant measurements from the Hubble Space Telescope, provide a constraint on the effective number of relativistic degrees of freedom 3.62+0.50-0.48 at 95% CL. New Planck data provide a unique opportunity to…
General dissipative coefficient in warm intermediate and logamediate inflation
Videla, Nelson; Herrera, Ramón; Olivares, Marco
We study a general form for the dissipative coefficient Γ(T,ϕ)=CϕTm/ϕm-1 in the context of warm intermediate and logamediate inflationary universe models. We analyze these models in the weak and strong dissipative regimes. In the slow-roll approximation, we describe in great detail the characteristics of these mode…
Solar Drivers of 11-yr and Long-Term Cosmic Ray Modulation
Richardson, I. G.; Ling, A. G.; Cliver, E. W.
In the current paradigm for the modulation of galactic cosmic rays (GCRs), diffusion is taken to be the dominant process during solar maxima while drift dominates at minima. Observations during the recent solar minimum challenge the pre-eminence of drift at such times. In 2009, the ∼2 GV GCR intensity measured by the Newark neutron monitor increas…
The small scale power asymmetry in the cosmic microwave background
Flender, Samuel; Hotchkiss, Shaun
We investigate the hemispherical power asymmetry in the cosmic microwave background on small angular scales. We find an anomalously high asymmetry in the multipole range l = 601-2048, with a naive statistical significance of 6.5σ. However, we show that this extreme anomaly is simply a coincidence of three other effects, relativistic power modulati…
Hα Star Formation Rates of z > 1 Galaxy Clusters in the IRAC Shallow Cluster Survey
Moustakas, John; Dey, Arjun; Gonzalez, Anthony H. +7 more
We present Hubble Space Telescope near-IR spectroscopy for 18 galaxy clusters at 1.0 <z < 1.5 in the IRAC Shallow Cluster Survey. We use Wide Field Camera 3 grism data to spectroscopically identify Hα emitters in both the cores of galaxy clusters as well as in field galaxies. We find a large cluster-to-cluster scatter in the star formation r…
First X-ray evidence for a shock at the Coma relic
Brüggen, M.; Ogrean, G. A.
The Coma cluster is one of the nearest galaxy clusters, and the first one in which a peripheral radio relic was discovered. However, X-ray observations of the plasma near the relic have been scarce. Here, we present results from a re-analysis of a 22 ks archival XMM-Newton observation. Across the relic, we detect a temperature discontinuity indica…
A Rest-frame Optical View on z ~ 4 Galaxies. I. Color and Age Distributions from Deep IRAC Photometry of the IUDF10 and GOODS Surveys
Trenti, M.; Oesch, P. A.; Bouwens, R. J. +7 more
We present a study of rest-frame UV-to-optical color distributions for z ~ 4 galaxies based on the combination of deep HST/ACS+WFC3/IR data with Spitzer/IRAC imaging. In particular, we use new, ultra-deep data from the IRAC Ultradeep Field program (IUDF10), together with previous, public IRAC data over the GOODS fields. Our sample contains a total…
Herschel reveals the obscured star formation in HiZELS Hα emitters at z = 1.47
Smail, I.; Berta, S.; Magnelli, B. +28 more
We describe the far-infrared (far-IR; rest-frame 8-1000-µm) properties of a sample of 443 Hα-selected star-forming galaxies in the Cosmic Evolution Survey (COSMOS) and Ultra Deep Survey (UDS) fields detected by the High-redshift Emission Line Survey (HiZELS) imaging survey. Sources are identified using narrow-band filters in combination with…
C IV Line-width Anomalies: The Perils of Low Signal-to-noise Spectra
Kochanek, C. S.; Vestergaard, M.; Peterson, B. M. +3 more
Comparison of six high-redshift quasar spectra obtained with the Large Binocular Telescope with previous observations from the Sloan Digital Sky Survey shows that failure to correctly identify absorption and other problems with accurate characterization of the C IV λ1549 emission line profile in low signal-to-noise (S/N) data can severely limit th…
Faint Submillimeter Galaxy Counts at 450 µm
Chen, Chian-Chou; Lee, Nicholas; Williams, Jonathan P. +5 more
We present the results of SCUBA-2 observations at 450 µm and 850 µm of the field lensed by the massive cluster A370. With a total survey area >100 arcmin2 and 1σ sensitivities of 3.92 and 0.82 mJy beam-1 at 450 and 850 µm, respectively, we find a secure sample of 20 sources at 450 µm and 26 sources …