Search Publications
The Nature and Frequency of Outflows from Stars in the Central Orion Nebula Cluster
O'Dell, C. R.; Henney, W. J.; Ferland, G. J. +3 more
Recent Hubble Space Telescope images have allowed the determination with unprecedented accuracy of motions and changes of shocks within the inner Orion Nebula. These originate from collimated outflows from very young stars, some within the ionized portion of the nebula and others within the host molecular cloud. We have doubled the number of Herbi…
The Chandra Local Volume Survey. I. The X-Ray Point Source Populations of NGC 55, NGC 2403, and NGC 4214
Dalcanton, J. J.; Skillman, E. D.; Kong, A. K. H. +7 more
We present comprehensive X-ray point source catalogs of NGC 55, NGC 2403, and NGC 4214 as part of the Chandra Local Volume Survey. The combined archival observations have effective exposure times of 56.5 ks, 190 ks, and 79 ks for NGC 55, NGC 2403, and NGC 4214, respectively. When combined with our published catalogs for NGC 300 and NGC 404, our su…
LUT Reveals a New Mass-transferring Semi-detached Binary
Zhang, J.; Zejda, M.; Zhang, B. +6 more
GQ Dra is a short-period eclipsing binary in a double stellar system that was discovered by Hipparcos. Complete light curves in the UV band were obtained with the Lunar-based Ultraviolet Telescope in 2014 November and December. Photometric solutions are determined using the W-D (Wilson and Devinney) method. It is discovered that GQ Dra is a classi…
The Chemical Composition of ρ Puppis and the Signs of Accretion in the Atmospheres of B-F-Type Stars
Lee, Byeong-Cheol; Kim, Sungeun; Lee, Jae-Woo +10 more
We investigated the chemical composition of ρ Pup using high-resolution spectral observations taken from the Very Large Telescope and the IUE archives and also spectra obtained at the 1.8 m telescope of the Bohyunsan observatory in Korea. The abundances of 56 chemical elements and the upper limits of Li and Be abundances were determined. The abund…
A Stacked Search for Intermediate-mass Black Holes in 337 Extragalactic Star Clusters
Miller-Jones, J. C. A.; Wrobel, J. M.; Nyland, K. E.
Forbes et al. recently used the Hubble Space Telescope to localize hundreds of candidate star clusters in NGC 1023, an early-type galaxy at a distance of 11.1 Mpc. Old stars dominate the light of 92% of the clusters and intermediate-age stars dominate the light of the remaining 8%. Theory predicts that clusters with such ages can host intermediate…
Nucleus and Mass Loss from Active Asteroid 313P/Gibbs
Mutchler, Max; Jewitt, David; Agarwal, Jessica +3 more
We present Hubble Space Telescope observations of active asteroid 313P/Gibbs (formerly P/2014 S4) taken over the five month interval from 2014 October to 2015 March. This object has been recurrently active near perihelion (at 2.4 AU) in two different orbits, a property that is naturally explained by the sublimation of near surface ice but which is…
Hubble Space Telescope Snapshot Search for Planetary Nebulae in Globular Clusters of the Local Group
Bond, Howard E.
Single stars in ancient globular clusters (GCs) are believed incapable of producing planetary nebulae (PNs), because their post-asymptotic-giant-branch evolutionary timescales are slower than the dissipation timescales for PNs. Nevertheless, four PNs are known in Galactic GCs. Their existence likely requires more exotic evolutionary channels, incl…
Tracking the Geysers of Enceladus into Saturn’s E Ring
Porco, C. C.; Mitchell, C. J.; Weiss, J. W.
We examine Cassini Imaging Science Subsystem images of the E ring taken over a period of almost 7 yr, from 2006 September to 2013 July, in which long, sinuous structures dubbed tendrils are present. We model these structures by numerically integrating the trajectories of particles launched from the sources of the most active geysers recently locat…
HST Astrometry in the 30 Doradus Region: Measuring Proper Motions of Individual Stars in the Large Magellanic Cloud
Anderson, Jay; van der Marel, Roeland P.; Sana, Hugues +5 more
We present measurements of positions and relative proper motions in the 30 Doradus region of the LMC. We detail the construction of a single-epoch astrometric reference frame, based on specially designed observations obtained with the two main imaging instruments Advanced Camera for Surveys/Wide Field Channel and Wide Field Camera 3/UVIS on board …
Uncovering the Nucleus Candidate for NGC 253
Schirmer, M.; Díaz, R. J.; Günthardt, G. I. +4 more
NGC 253 is the nearest spiral galaxy with a nuclear starburst that becomes the best candidate for studying the relationship between starburst and active galactic nucleus activity. However, this central region is veiled by large amounts of dust, and it has been so far unclear which is the true dynamical nucleus to the point that there is no strong …