Search Publications
Galaxy Structure and Mode of Star Formation in the SFR-Mass Plane from z ~ 2.5 to z ~ 0.1
Barro, Guillermo; Hathi, Nimish P.; Kocevski, Dale D. +23 more
We analyze the dependence of galaxy structure (size and Sérsic index) and mode of star formation (ΣSFR and SFRIR/SFRUV) on the position of galaxies in the star formation rate (SFR) versus mass diagram. Our sample comprises roughly 640,000 galaxies at z ~ 0.1, 130,000 galaxies at z ~ 1, and 36,000 galaxies at z ~ 2.…
Coronal Mass Ejections: Models and Their Observational Basis
Chen, P. F.
Coronal mass ejections (CMEs) are the largest-scale eruptive phenomenon in the solar system, expanding from active region-sized nonpotential magnetic structure to a much larger size. The bulk of plasma with a mass of ∼ 1011,1013 kg is hauled up all the way out to the interplanetary space with a typical velocity of several hun…
Characterizing interstellar filaments with Herschel in IC 5146
Hill, T.; André, Ph.; Arzoumanian, D. +21 more
We provide a first look at the results of the Herschel Gould Belt survey toward the IC 5146 molecular cloud and present a preliminary analysis of the filamentary structure in this region. The column density map, derived from our 70-500 µm Herschel data, reveals a complex network of filaments and confirms that these filaments are the main bir…
The Second Catalog of Active Galactic Nuclei Detected by the Fermi Large Area Telescope
Ozaki, M.; Troja, E.; Caraveo, P. A. +174 more
The second catalog of active galactic nuclei (AGNs) detected by the Fermi Large Area Telescope (LAT) in two years of scientific operation is presented. The second LAT AGN catalog (2LAC) includes 1017 γ-ray sources located at high Galactic latitudes (|b| > 10°) that are detected with a test statistic (TS) greater than 25 and associated statistic…
Subsurface water and clay mineral formation during the early history of Mars
Murchie, Scott L.; Ehlmann, Bethany L.; Mustard, John F. +4 more
Clay minerals, recently discovered to be widespread in Mars's Noachian terrains, indicate long-duration interaction between water and rock over 3.7 billion years ago. Analysis of how they formed should indicate what environmental conditions prevailed on early Mars. If clays formed near the surface by weathering, as is common on Earth, their presen…
The Sins Survey of z ~ 2 Galaxy Kinematics: Properties of the Giant Star-forming Clumps
Lutz, D.; Förster Schreiber, N. M.; Genzel, R. +24 more
We have studied the properties of giant star-forming clumps in five z ~ 2 star-forming disks with deep SINFONI AO spectroscopy at the ESO VLT. The clumps reside in disk regions where the Toomre Q-parameter is below unity, consistent with their being bound and having formed from gravitational instability. Broad Hα/[N II] line wings demonstrate that…
Ultraviolet Luminosity Functions from 132 z ~ 7 and z ~ 8 Lyman-break Galaxies in the Ultra-deep HUDF09 and Wide-area Early Release Science WFC3/IR Observations
Trenti, M.; Oesch, P. A.; Carollo, C. M. +8 more
We identify 73 z ~ 7 and 59 z ~ 8 candidate galaxies in the reionization epoch, and use this large 26-29.4 AB mag sample of galaxies to derive very deep luminosity functions to < - 18 AB mag and the star formation rate (SFR) density at z ~ 7 and z ~ 8 (just 800 Myr and 650 Myr after recombination, respectively). The galaxy sample is derived usi…
The Chandra Deep Field-South Survey: 4 Ms Source Catalogs
Smail, I.; Lehmer, B. D.; Hornschemeier, A. E. +22 more
We present source catalogs for the 4 Ms Chandra Deep Field-South (CDF-S), which is the deepest Chandra survey to date and covers an area of 464.5 arcmin2. We provide a main Chandra source catalog, which contains 740 X-ray sources that are detected with WAVDETECT at a false-positive probability threshold of 10-5 in at least on…
A new, lower value of total solar irradiance: Evidence and climate significance
Lean, Judith L.; Kopp, Greg
The most accurate value of total solar irradiance during the 2008 solar minimum period is 1360.8 ± 0.5 W m-2 according to measurements from the Total Irradiance Monitor (TIM) on NASA's Solar Radiation and Climate Experiment (SORCE) and a series of new radiometric laboratory tests. This value is significantly lower than the canonical val…
Relativistic jet activity from the tidal disruption of a star by a massive black hole
Troja, E.; Im, M.; Sakamoto, T. +55 more
Supermassive black holes have powerful gravitational fields with strong gradients that can destroy stars that get too close, producing a bright flare in ultraviolet and X-ray spectral regions from stellar debris that forms an accretion disk around the black hole. The aftermath of this process may have been seen several times over the past two deca…