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Kinematics of the Orion Trapezium Based on Diffracto-Astrometry and Historical Data
Olivares, J.; Sánchez, L. J.; Ruelas-Mayorga, A. +3 more
Using the novel Diffracto-Astrometry technique, we analyze 44 Hubble Space Telescope Wide Field Planetary Camera 2 images of the Orion Trapezium (OT) taken over a span of 12 yr (1995-2007). We measure the relative positions of the six brighter OT components (A-F) and supplement these results with measurements of the relative separations and positi…
Analysis of Detached Eclipsing Binaries near the Turnoff of the Open Cluster NGC 7142
Orosz, Jerome; Shetrone, Matthew; Sandquist, Eric L. +1 more
We analyze extensive BVRCIC photometry and radial velocity measurements for three double-lined deeply eclipsing binary stars in the field of the old open cluster NGC 7142. The short period (P = 1.9096825 days) detached binary V375 Cep is a high probability cluster member, and has a total eclipse of the secondary star. The cha…
Companions to nearby Stars with Astrometric Acceleration. II
Tokovinin, Andrei; Hayward, Thomas L.; Hartung, Markus
Hipparcos astrometric binaries were observed with the NICI adaptive optics system at Gemini-S, completing the work of Paper I. Among the 65 F, G, and K dwarfs within 67 pc of the Sun studied here, we resolve 18 new subarcsecond companions, remeasure 7 known astrometric pairs, and establish the physical nature of yet another 3 wider companions. The…
Structural Parameters for Globular Clusters in M31
Ma, Jun; Wang, Song
In this paper, we present surface brightness profiles for 79 globular clusters in M31, using images observed with the Hubble Space Telescope, some of which are from new observations. The structural and dynamical parameters are derived from fitting the profiles to several different models for the first time. The results show that in the majority of…
On the Density Profile of the Globular Cluster M92
Walker, A. R.; Stetson, P. B.; Bono, G. +10 more
We present new number density and surface brightness profiles for the globular cluster M92 (NGC 6341). These profiles are calculated from optical images collected with the CCD mosaic camera MegaCam at the Canada-France-Hawaii Telescope and with the Advanced Camera for Surveys on the Hubble Space Telescope. The ground-based data were supplemented w…
Astrometry and Orbits of Nix, Kerberos, and Hydra
Buie, Marc W.; Grundy, William M.; Tholen, David J.
We present new Hubble Space Telescope observations of three of Pluto's outer moons, Nix, Kerberos, and Hydra. This work revises previously published astrometry of Nix and Hydra from 2002 to 2003. New data from a four-month span during 2007 include observations designed to better measure the positions of Nix and Hydra. A third data set from 2010 al…
AKARI Infrared Camera Survey of the Large Magellanic Cloud. II. The Near-infrared Spectroscopic Catalog
Onaka, Takashi; Ita, Yoshifusa; Sakon, Itsuki +4 more
We performed a near-infrared spectroscopic survey toward an area of ~10 deg2 of the Large Magellanic Cloud (LMC) with the infrared satellite AKARI. Observations were carried out as part of the AKARI Large-area Survey of the Large Magellanic Cloud (LSLMC). The slitless multi-object spectroscopic capability of the AKARI/IRC enabled us to …
Spectroscopy along Multiple, Lensed Sight Lines through Outflowing Winds in the Quasar SDSS J1029+2623
Gandhi, Poshak; Oguri, Masamune; Misawa, Toru +3 more
We study the origin of absorption features on the blue side of the C IV broad emission line of the large-separation lensed quasar SDSS J1029+2623 at z em ~ 2.197. The quasar images, produced by a foreground cluster of galaxies, have a maximum separation angle of θ ~ 22.''5. The large angular separation suggests that the sight lines to t…
The Massive Star Population in M101. I. The Identification and Spatial Distribution of the Visually Luminous Stars
Humphreys, Roberta M.; Grammer, Skyler
An increasing number of non-terminal giant eruptions are being observed by modern supernova and transient surveys. But very little is known about the origin of these giant eruptions and their progenitors, many of which are presumably very massive, evolved stars. Motivated by the small number of progenitors positively associated with these giant er…
Enigmatic Recurrent Pulsational Variability of the Accreting White Dwarf EQ Lyn (SDSS J074531.92+453829.6)
Drake, A. J.; Hermes, J. J.; Montgomery, M. H. +19 more
Photometric observations of the cataclysmic variable EQ Lyn (SDSS J074531.92+453829.6), acquired from 2005 October to 2006 January, revealed high-amplitude variability in the range 1166-1290 s. This accreting white dwarf underwent an outburst in 2006 October, during which its brightness increased by at least five magnitudes, and it started exhibit…