Search Publications
VII Zw 403: H I Structure in a Blue Compact Dwarf Galaxy
Östlin, Göran; Brinks, Elias; Elmegreen, Bruce G. +9 more
We present optical (UBVJ), ultraviolet (FUV, NUV), and high-resolution atomic hydrogen (H I) observations of the nearby blue compact dwarf (BCD), VII Zw 403. We find that VII Zw 403 has a relatively high H I mass-to-light ratio for a BCD. The rotation velocity is nominally 10-15 km s-1, but rises to ~20 km s-1 after correctio…
Variable Stars in Large Magellanic Cloud Globular Clusters. I. NGC 1466
Pritzl, Barton J.; Smith, Horace A.; De Lee, Nathan +3 more
This is the first in a series of papers studying the variable stars in Large Magellanic Cloud globular clusters. The primary goal of this series is to better understand how the RR Lyrae stars in Oosterhoff-intermediate systems compare to those in Oosterhoff I/II systems. In this paper, we present the results of our new time-series BV photometric s…
IRAS 17423-1755 (Hen 3-1475) Revisited: An O-rich High-mass Post-asymptotic Giant Branch Star
García-Lario, P.; Manteiga, M.; Ulla, A. +2 more
The high-resolution (R ~ 600) Spitzer/IRS spectrum of the bipolar protoplanetary nebula (PN) IRAS 17423-1755 is presented in order to clarify the dominant chemistry (C-rich versus O-rich) of its circumstellar envelope as well as to constrain its evolutionary stage. The high-quality Spitzer/IRS spectrum shows weak 9.7 µm absorption from amorp…
Pre-discovery Observations of Disrupting Asteroid P/2010 A2
Jewitt, David; Li, Jing; Stuart, Joseph S.
Solar system object P/2010 A2 is the first-noticed example of the aftermath of a recently disrupted asteroid, probably resulting from a collision. Nearly a year elapsed between its inferred initiation in early 2009 and its eventual detection in early 2010. Here, we use new observations to assess the factors underlying the visibility, especially to…
The Quasar/Galaxy Pair PKS 1327-206/ESO 1327-2041: Absorption Associated with a Recent Galaxy Merger
Danforth, Charles W.; Stocke, John T.; Keeney, Brian A. +1 more
We present HST/WFPC2 broadband and ground-based Hα images, H I 21 cm emission maps, and low-resolution optical spectra of the nearby galaxy ESO 1327-2041, which is located 38'' (14 h -1 70 kpc in projection) west of the quasar PKS 1327-206. Our Hubble Space Telescope (HST) images reveal that ESO 1327-2041 has a complex optica…
A Kinematic and Photometric Study of the Galactic Young Star Cluster NGC 7380
Chen, W. P.; Chen, Li; Sharma, Saurabh +6 more
We present proper motions, radial velocities, and a photometric study of the Galactic open cluster NGC 7380, which is associated with prominent emission nebulosity and dark molecular clouds. On the basis of the sample of highly probable member stars, the star cluster is found to be at a distance of 2.6 ± 0.4 kpc, has an age of around 4 Myr, and a …
Star Formation Properties in Barred Galaxies (SFB). I. Ultraviolet to Infrared Imaging and Spectroscopic Studies of NGC 7479
Wu, Hong; Cao, Chen; Meng, Xian-Min +1 more
Large-scale bars and minor mergers are important drivers for the secular evolution of galaxies. Based on ground-based optical images and spectra as well as ultraviolet data from the Galaxy Evolution Explorer and infrared data from the Spitzer Space Telescope, we present a multi-wavelength study of star formation properties in the barred galaxy NGC…
No Confirmed New Isolated Neutron Stars in the SDSS Data Release 4
Anderson, Scott F.; Haberl, Frank; Rosenfield, Philip +6 more
We report on follow-up observations of candidate X-ray-bright, radio-quiet isolated neutron stars (INSs) identified from correlations of the ROSAT All-Sky Survey (RASS) and the Sloan Digital Sky Survey (SDSS) Data Release 4 in Agüeros et al. We obtained Chandra X-ray Observatory exposures for 13 candidates in order to pinpoint the source of X-ray …
Close to the Dredge: Precise X-Ray C and N Abundances in λ Andromeda and Its Precocious Red Giant Branch Mixing Problem
Ness, J. -U.; Drake, Jeremy J.; Eldridge, John J. +2 more
Chandra LETG+HRC-S and XMM-Newton RGS spectra of H-like C and N lines formed in the corona of the primary star of the RS CVn-type binary λ And, a mildly metal-poor G8 III-IV first ascent giant that completed dredge-up ~50 Myr ago, have been used to make a precise measurement of its surface C/N ratio. We obtain the formal result [C/N] = 0.03 ± 0.07…
The Internal Proper Motions of Stars in the Open Cluster M35
Harrison, Thomas E.; Benedict, G. Fritz; McArthur, Barbara E. +1 more
Relative proper motions, based on 108 orbits of Hubble Space Telescope Fine Guidance Sensor data extending from 1992 to 2006, are reported for 74 stars in the open cluster M35 (NGC 2168). A subset of 22 of these objects are then used to compute the cluster's internal proper motion dispersions in both right ascension and declination. We find that t…