Search Publications
Teasing bits of information out of the CMB energy spectrum
Jeong, Donghui; Chluba, Jens
Departures of the cosmic microwave background (CMB) frequency spectrum from a blackbody - commonly referred to as spectral distortions - encode information about the thermal history of the early Universe (redshift z ≲ few × 106). While the signal is usually characterized as µ- and y-type distortion, a smaller residual (non-y/non-&…
A Guide to Designing Future Ground-based Cosmic Microwave Background Experiments
Lee, A. T.; Zahn, O.; Errard, J. +5 more
In this follow-up work to the high energy physics Community Summer Study 2013 (aka SNOWMASS), we explore the scientific capabilities of a future Stage IV cosmic microwave background polarization experiment under various assumptions on detector count, resolution, and sky coverage. We use the Fisher matrix technique to calculate the expected uncerta…
Formation of a Double-decker Magnetic Flux Rope in the Sigmoidal Solar Active Region 11520
Cheng, X.; Ding, M. D.; Zhang, J. +5 more
In this paper, we address the formation of a magnetic flux rope (MFR) that erupted on 2012 July 12 and caused a strong geomagnetic storm event on July 15. Through analyzing the long-term evolution of the associated active region observed by the Atmospheric Imaging Assembly and the Helioseismic and Magnetic Imager on board the Solar Dynamics Observ…
Relic neutrinos, thermal axions, and cosmology in early 2014
Di Valentino, Eleonora; Melchiorri, Alessandro; Mena, Olga +2 more
We present up-to-date cosmological bounds on the sum of active neutrino masses as well as on extended cosmological scenarios with additional thermal relics, as thermal axions or sterile neutrino species. Our analyses consider all the current available cosmological data in the beginning of year 2014, including the very recent and most precise baryo…
Cosmological Constraints on Brans-Dicke Theory
Avilez, A.; Skordis, C.
We report strong cosmological constraints on the Brans-Dicke (BD) theory of gravity using cosmic microwave background data from Planck. We consider two types of models. First, the initial condition of the scalar field is fixed to give the same effective gravitational strength Geff today as the one measured on Earth, GN. In th…
CLASH-X: A Comparison of Lensing and X-Ray Techniques for Measuring the Mass Profiles of Galaxy Clusters
Donahue, Megan; Voit, G. Mark; Broadhurst, Tom +35 more
We present profiles of temperature, gas mass, and hydrostatic mass estimated from new and archival X-ray observations of CLASH clusters. We compare measurements derived from XMM and Chandra observations with one another and compare both to gravitational lensing mass profiles derived with CLASH Hubble Space Telescope and Subaru Telescope lensing da…
The Redshift Evolution of the Mean Temperature, Pressure, and Entropy Profiles in 80 SPT-Selected Galaxy Clusters
Gladders, M. D.; Rest, A.; Foley, R. J. +63 more
We present the results of an X-ray analysis of 80 galaxy clusters selected in the 2500 deg2 South Pole Telescope survey and observed with the Chandra X-ray Observatory. We divide the full sample into subsamples of ~20 clusters based on redshift and central density, performing a joint X-ray spectral fit to all clusters in a subsample sim…
The observational status of Galileon gravity after Planck
Baugh, Carlton M.; Barreira, Alexandre; Li, Baojiu +1 more
We use the latest CMB data from Planck, together with BAO measurements, to constrain the full parameter space of Galileon gravity. We constrain separately the three main branches of the theory known as the Cubic, Quartic and Quintic models, and find that all yield a very good fit to these data. Unlike in ΛCDM, the Galileon model constraints are co…
ALMA resolves turbulent, rotating [CII] emission in a young starburst galaxy at z = 4.8
Smail, Ian; Maiolino, Roberto; Caselli, Paola +9 more
We present spatially resolved Atacama Large Millimeter/submillimeter Array (ALMA) [Cii] observations of the z = 4.7555 submillimetre galaxy, ALESS 73.1. Our 0.̋5 FWHM map resolves the [Cii] emitting gas which is centred close to the active galactic nucleus (AGN). The gas kinematics are dominated by rotation but with high turbulence, vrot…
A multiwavelength consensus on the main sequence of star-forming galaxies at z ∼ 2
Berta, S.; Magnelli, B.; Lutz, D. +18 more
We compare various star formation rate (SFR) indicators for star-forming galaxies at 1.4 < z < 2.5 in the COSMOS field. The main focus is on the SFRs from the far-IR (PACS-Herschel data) with those from the ultraviolet, for galaxies selected according to the BzK criterion. FIR-selected samples lead to a vastly different slope of the SFR-stel…