Search Publications
Solar Occultation by Titan Measured by Cassini/UVIS
Koskinen, Tommi T.; Yelle, Roger V.; McClintock, William E. +4 more
We present the first published analysis of a solar occultation by Titan's atmosphere measured by the Ultraviolet Imaging Spectrograph on board Cassini. The data were measured during flyby T53 in 2009 April and correspond to latitudes between 21° and 28° south. The analysis utilizes the absorption of two solar emission lines (584 Å and 630 Å) in th…
The Production Rate of SN Ia Events in Globular Clusters
Bregman, Joel N.; Washabaugh, Pearce C.
In globular clusters, dynamical evolution produces luminous X-ray emitting binaries at a rate about 200 times greater than in the field. If globular clusters also produce SN Ia at a high rate, it would account for many of the SN Ia production in early-type galaxies and provide insight into their formation. Here we use archival Hubble Space Telesco…
Direct Observations of Plasma Upflows and Condensation in a Catastrophically Cooling Solar Transition Region Loop
Patel, M.; Champey, P.; Orange, N. B. +3 more
Minimal observational evidence exists for fast transition region (TR) upflows in the presence of cool loops. Observations of such occurrences challenge notions of standard solar atmospheric heating models as well as their description of bright TR emission. Using the EUV Imaging Spectrometer on board Hinode, we observe fast upflows (v λ …
Enhanced Nitrogen in Morphologically Disturbed Blue Compact Galaxies at 0.20 < z < 0.35: Probing Galaxy Merging Features
Rey, Soo-Chang; Kyeong, Jaemann; Sung, Eon-Chang +4 more
We present a study of correlations between the elemental abundances and galaxy morphologies of 91 blue compact galaxies (BCGs) at z = 0.20-0.35 with Sloan Digital Sky Survey (SDSS) DR7 data. We classify the morphologies of the galaxies as either "disturbed" or "undisturbed" by visual inspection of the SDSS images, and using the Gini coefficient an…
Stacking Star Clusters in M51: Searching for Faint X-Ray Binaries
Barmby, P.; Vulic, N.; Gallagher, S. C.
The population of low-luminosity (<1035 erg s-1) X-ray binaries (XRBs) has been investigated in our Galaxy and M31 but not further. To address this problem, we have used data from the Chandra X-Ray Observatory and the Hubble Space Telescope to investigate the faint population of XRBs in the grand-design spiral galaxy M51. …
Mid-infrared Spectral Properties of Post-starburst Quasars
Hines, Dean C.; Dale, Daniel A.; Canalizo, Gabriela +5 more
We present Spitzer InfraRed Spectrograph low-resolution spectra of 16 spectroscopically selected post-starburst quasars (PSQs) at z ~ 0.3. The optical spectra of these broad-lined active galactic nuclei (AGNs) simultaneously show spectral signatures of massive intermediate-aged stellar populations making them good candidates for studying the conne…
Photometric Redshifts of Submillimeter Galaxies
Berta, Stefano; Pozzi, Francesca; Chakrabarti, Sukanya +4 more
We use the photometric redshift method of Chakrabarti & McKee to infer photometric redshifts of submillimeter galaxies with far-IR (FIR) Herschel data obtained as part of the PACS Evolutionary Probe program. For the sample with spectroscopic redshifts, we demonstrate the validity of this method over a large range of redshifts (4 >~ z >~ …
Cross-field Diffusion of Energetic (100 keV to 2 MeV) Protons in Interplanetary Space
Tsurutani, Bruce T.; Echer, Ezequiel; Lakhina, Gurbax S. +2 more
Magnetic field magnitude decreases (MDs) are observed in several regions of the interplanetary medium. In this paper, we characterize MDs observed by the Ulysses spacecraft instrumentation over the solar south pole by using magnetic field data to obtain the empirical size, magnetic field MD, and frequency of occurrence distribution functions. The …
Herschel/HIFI Search for H_2^{17}O and H_2^{18}O in IRC+10216: Constraints on Models for the Origin of Water Vapor
Cernicharo, José; Agúndez, Marcelino; Szczerba, Ryszard +7 more
We report the results of a sensitive search for the minor isotopologues of water, H_2^{17}O and H_2^{18}O, toward the carbon-rich asymptotic giant branch star IRC+10216 (a.k.a. CW Leonis) using the HIFI instrument on the Herschel Space Observatory. This search was motivated by the fact that any detection of isotopic enhancement in the H_2^{17}O an…
The Broad Line Region in NGC 4051: An Inflow Illuminated by a 105 K Accretion Disk
Devereux, Nick; Heaton, Emily
Adopting a spherically symmetric steady-state ballistic inflow as the kinematic model for the gas distribution responsible for producing the Hα emission line, and a central black hole (BH) mass of 1.7 × 106 M ⊙ determined from prior reverberation mapping, leads to the following dimensions for the size of the broad line region…