Search Publications
Subsurface Radar Sounding of the South Polar Layered Deposits of Mars
Gurnett, Donald A.; Stofan, Ellen R.; Frigeri, Alessandro +21 more
The ice-rich south polar layered deposits of Mars were probed with the Mars Advanced Radar for Subsurface and Ionospheric Sounding on the Mars Express orbiter. The radar signals penetrate deep into the deposits (more than 3.7 kilometers). For most of the area, a reflection is detected at a time delay that is consistent with an interface between th…
Modeling the emission processes in blazars
Böttcher, Markus
Blazars are the most violent steady/recurrent sources of high-energy gamma-ray emission in the known Universe. They are prominent emitters of electromagnetic radiation throughout the entire electromagnetic spectrum. The observable radiation most likely originates in a relativistic jet oriented at a small angle with respect to the line of sight. Th…
On the Progenitor of SN 2005gl and the Nature of Type IIn Supernovae
Cenko, S. B.; Filippenko, Alexei V.; Aldering, G. +9 more
We present a study of the Type IIn supernova (SN) 2005gl, in the relatively nearby (d~66 Mpc) galaxy NGC 266. Photometry and spectroscopy of the SN indicate that it is a typical member of its class. Pre-explosion Hubble Space Telescope (HST) imaging of the location of the SN, along with a precise localization of this event using the laser guide st…
Dark matter maps reveal cosmic scaffolding
Refregier, Alexandre; Ellis, Richard; Mobasher, Bahram +17 more
Ordinary baryonic particles (such as protons and neutrons) account for only one-sixth of the total matter in the Universe. The remainder is a mysterious `dark matter' component, which does not interact via electromagnetism and thus neither emits nor reflects light. As dark matter cannot be seen directly using traditional observations, very little …
CRISM multispectral summary products: Parameterizing mineral diversity on Mars from reflectance
Bibring, J. -P.; Gendrin, A.; Gondet, B. +9 more
The Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) aboard the Mars Reconnaissance Orbiter (MRO) is the most recent spectrometer to arrive at Mars. The instrument is a hyperspectral imager covering visible to near-infrared wavelengths (0.37-3.92 µm at 6.55 nm/channel). Summary products based on multispectral parameters will be d…
The ACS Survey of Galactic Globular Clusters. II. Stellar Evolution Tracks, Isochrones, Luminosity Functions, and Synthetic Horizontal-Branch Models
Anderson, Jay; Dotter, Aaron; Baron, E. +4 more
The ACS Survey of Galactic Globular Clusters, an HST Treasury Project, will deliver high-quality, homogeneous photometry of 65 globular clusters. This paper introduces a new collection of stellar evolution tracks and isochrones suitable for analyzing the ACS survey data. Stellar evolution models were computed at [Fe/H]=-2.5, -2.0, -1.5, -1.0, -0.5…
The XMM-Newton Wide-Field Survey in the COSMOS Field: Statistical Properties of Clusters of Galaxies
Finoguenov, A.; Böhringer, H.; Kneib, J. -P. +30 more
We present the results of a search for galaxy clusters in the first 36 XMM-Newton pointings on the Cosmic Evolution Survey (COSMOS) field. We reach a depth for a total cluster flux in the 0.5-2 keV band of 3×10-15 ergs cm-2 s-1, having one of the widest XMM-Newton contiguous raster surveys, covering an area of 2.1 …
A kinematical approach to dark energy studies
Allen, Steven W.; Rapetti, David; Blandford, Roger D. +1 more
We present and employ a new kinematical approach to cosmological `dark energy' studies. We construct models in terms of the dimensionless second and third derivatives of the scalefactor a(t) with respect to cosmic time t, namely the present-day value of the deceleration parameter q0 and the cosmic jerk parameter, j(t). An elegant featur…
A Complete Sample of 12 Very X-Ray Luminous Galaxy Clusters at z > 0.5
Edge, A. C.; Ebeling, H.; Ma, C. -J. +3 more
We present the statistically complete and cosmologically most relevant subset of the 12 most distant galaxy clusters detected at z>0.5 by the Massive Cluster Survey (MACS). Ten of these systems are new discoveries; only two (MACS J0018.5+1626, aka Cl 0016+1609, and MACS J0454.1-0300, aka MS 0451.6-0305) were previously known. We provide fundame…
On the Magnetic Flux Budget in Low-Corona Magnetic Reconnection and Interplanetary Coronal Mass Ejections
Qiu, Jiong; Hu, Qiang; Howard, Timothy A. +1 more
We present the first quantitative comparison between the total magnetic reconnection flux in the low corona in the wake of coronal mass ejections (CMEs) and the magnetic flux in magnetic clouds (MCs) that reach 1 AU 2-3 days after CME onset. The total reconnection flux is measured from flare ribbons, and the MC flux is computed using in situ obser…