Search Publications
Galaxy Structure in the Ultraviolet: The Dependence of Morphological Parameters on Rest-frame Wavelength
Conselice, Christopher J.; Madore, Barry F.; Windhorst, Rogier A. +5 more
Evolutionary studies that compare galaxy structure as a function of redshift are complicated by the fact that any particular galaxy’s appearance depends in part on the rest-frame wavelength of the observation. This leads to the necessity for a “morphological k-correction” between different passbands, especially when comparing the rest-frame optica…
Centre-excised X-ray luminosity as an efficient mass proxy for future galaxy cluster surveys
Allen, Steven W.; Mantz, Adam B.; von der Linden, Anja +1 more
The cosmological constraining power of modern galaxy cluster catalogues can be improved by obtaining low-scatter mass proxy measurements for even a small fraction of sources. In the context of large upcoming surveys that will reveal the cluster population down to the group scale and out to high redshifts, efficient strategies for obtaining such ma…
Cloud morphology and dynamics in Saturn's northern polar region
del Río-Gaztelurrutia, Teresa; Sánchez-Lavega, Agustín; Antuñano, Arrate +1 more
We present a study of the cloud morphology and motions in the north polar region of Saturn, from latitude ∼ 70°N to the pole based on Cassini ISS images obtained between January 2009 and November 2014. This region shows a variety of dynamical structures: the permanent hexagon wave and its intense eastward jet, a large field of permanent ;puffy; cl…
The Nucleus of Active Asteroid 311P/(2013 P5) PANSTARRS
Mutchler, Max; Jewitt, David; Agarwal, Jessica +3 more
The unique inner-belt asteroid 311P/PANSTARRS (formerly P/2013 P5) is notable for its sporadic, comet-like ejection of dust in nine distinct epochs spread over ∼250 days in 2013. This curious behavior has been interpreted as the product of localized, equatorward landsliding from the surface of an asteroid rotating at the brink of instability. We o…
Where are Compton-thick radio galaxies? A hard X-ray view of three candidates
Bird, A. J.; Ubertini, P.; Malizia, A. +4 more
We present a broad-band X-ray spectral analysis of the radio-loud active galactic nuclei NGC 612, 4C 73.08 and 3C 452, exploiting archival data from NuSTAR, XMM-Newton, Swift and INTEGRAL. These Compton-thick candidates are the most absorbed sources among the hard X-ray selected radio galaxies studied in Panessa et al. We find an X-ray absorbing c…
Spitzer Observations of the North Ecliptic Pole
Im, M.; Lee, H. M.; Clements, D. L. +19 more
We present a photometric catalog for Spitzer Space Telescope warm mission observations of the North Ecliptic Pole (NEP; centered at R.A. = 18h00m00s, decl. = 66d33m38.ˢ552). The observations are conducted with IRAC in the 3.6 and 4.5 µm bands over an area of 7.04 deg2, reachin…
Field-Aligned Currents in Saturn's Nightside Magnetosphere: Subcorotation and Planetary Period Oscillation Components During Northern Spring
Dougherty, M. K.; Alexeev, I. I.; Belenkaya, E. S. +7 more
We newly analyze Cassini magnetic field data from the 2012/2013 Saturn northern spring interval of highly inclined orbits and compare them with similar data from late southern summer in 2008, thus providing unique information on the seasonality of the currents that couple momentum between Saturn's ionosphere and magnetosphere. Inferred meridional …
Supergiant fast X-ray transients versus classical supergiant high mass X-ray binaries: Does the difference lie in the companion wind?
Bozzo, E.; Paul, B.; Pradhan, P.
We present a comparative study of stellar winds in classical supergiant high mass X-ray binaries (SgXBs) and supergiant fast X-ray transients (SFXTs) based on the analysis of publicly available out-of-eclipse observations performed with Suzaku and XMM-Newton. Our data set includes 55 observations of classical SgXBs and 21 observations of SFXTs. We…
Abundances and Depletions of Neutron-capture Elements in the Interstellar Medium
Lambert, D. L.; Federman, S. R.; Ritchey, A. M.
We present an extensive analysis of the gas-phase abundances and depletion behaviors of neutron-capture elements in the interstellar medium (ISM). Column densities (or upper limits to the column densities) of Ga II, Ge II, As II, Kr I, Cd II, Sn II, and Pb II are determined for a sample of 69 sight lines with high- and/or medium-resolution archiva…
The UV Emission of Stars in the LAMOST Survey. I. Catalogs
Zhang, Yong; Bai, Yu; Wang, Song +11 more
We present the ultraviolet magnitudes for over three million stars in the LAMOST survey, in which 2,202,116 stars are detected by GALEX. For 889,235 undetected stars, we develop a method to estimate their upper limit magnitudes. The distribution of (FUV - NUV) shows that the color declines with increasing effective temperature for stars hotter tha…