Search Publications
X-Ray and Optical Observations of A 0535+26
Guiriec, S.; Coe, M. J.; McBride, V. A. +13 more
We present recent contemporaneous X-ray and optical observations of the Be/X-ray binary system A 0535+26 with the Fermi/Gamma-ray Burst Monitor (GBM) and several ground-based observatories. These new observations are put into the context of the rich historical data (since ~1978) and discussed in terms of the neutron-star-Be-disk interaction. The B…
On the Link between Associated Mg II Absorbers and Star Formation in Quasar Hosts
Shen, Yue; Ménard, Brice
A few percent of quasars show strong associated Mg II absorption, with velocities (v off) lying within a few thousand km s-1 from the quasar systemic redshift. These associated absorption line (AAL) systems are usually interpreted as absorbers that are either intrinsic to the quasar and its host, or arising from external gala…
Suzaku Observation of the Black Hole Candidate Maxi J1836-194 in a Hard/Intermediate Spectral State
Fabian, A. C.; Miller, J. M.; Reis, R. C. +2 more
We report on a Suzaku observation of the newly discovered X-ray binary MAXI J1836-194. The source is found to be in the hard/intermediate spectral state and displays a clear and strong relativistically broadened iron emission line. We fit the spectra with a variety of phenomenological, as well as physically motivated disk reflection models, and fi…
High-contrast Near-infrared Polarization Imaging of MWC480
Kuzuhara, M.; Tamura, M.; Ishii, M. +52 more
One of the key predictions of modeling from the IR excess of Herbig Ae stars is that for protoplanetary disks, where significant grain growth and settling has occurred, the dust disk has flattened to the point that it can be partially or largely shadowed by the innermost material at or near the dust sublimation radius. When the self-shadowing has …
Detection of the Second r-process Peak Element Tellurium in Metal-poor Stars
Beers, Timothy C.; Roederer, Ian U.; Frebel, Anna +6 more
Using near-ultraviolet spectra obtained with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope, we detect neutral tellurium in three metal-poor stars enriched by products of r-process nucleosynthesis, BD +17 3248, HD 108317, and HD 128279. Tellurium (Te, Z = 52) is found at the second r-process peak (A ≈ 130) associated …
The Herschel and IRAM CHESS Spectral Surveys of the Protostellar Shock L1157-B1: Fossil Deuteration
Codella, C.; Ceccarelli, C.; Caselli, P. +9 more
We present the first study of deuteration toward the protostellar shock L1157-B1, based on spectral surveys performed with the Herschel-HIFI and IRAM 30 m telescopes. The L1157 outflow is driven by a low-mass Class 0 protostar and is considered the prototype of the so-called chemically active outflows. The young (2000 yr), bright blueshifted bow s…
The Spatial Distribution of Dust and Stellar Emission of the Magellanic Clouds
Bot, Caroline; Lebouteiller, Vianney; Bernard, Jean-Philippe +24 more
We study the emission by dust and stars in the Large and Small Magellanic Clouds, a pair of low-metallicity nearby galaxies, as traced by their spatially resolved spectral energy distributions. This project combines Herschel Space Observatory PACS and SPIRE far-infrared photometry with other data at infrared and optical wavelengths (the data were …
Spectroscopic Detection of Carbon Monoxide in the Young Supernova Remnant Cassiopeia A
Reach, W. T.; Rho, J.; Onaka, T. +1 more
We report the detection of carbon monoxide (CO) emission from the young supernova remnant Cassiopeia A (Cas A) at wavelengths corresponding to the fundamental vibrational mode at 4.65 µm. We obtained AKARI Infrared Camera spectra toward four positions which unambiguously reveal the broad characteristic CO ro-vibrational band profile. The obs…
Herschel Detection of Dust Emission from UV-luminous Star-forming Galaxies at 3.3 <~ z <~ 4.3
Reddy, Naveen; Dey, Arjun; Alberts, Stacey +5 more
We report the Herschel/SPIRE detection of dust emission arising from UV-luminous (L >~ L*) star-forming galaxies at 3.3 <~ z <~ 4.3. Our sample of 1913 Lyman break galaxy (LBG) candidates is selected over an area of 5.3 deg2 in the Boötes field of the NOAO Deep Wide-Field Survey. This is one of the largest samples of UV-luminou…
Coronal Heating by Surface Alfvén Wave Damping: Implementation in a Global Magnetohydrodynamics Model of the Solar Wind
Gombosi, T. I.; Frazin, R.; Sokolov, I. V. +5 more
The heating and acceleration of the solar wind is an active area of research. Alfvén waves, because of their ability to accelerate and heat the plasma, are a likely candidate in both processes. Many models have explored wave dissipation mechanisms which act either in closed or open magnetic field regions. In this work, we emphasize the boundary be…