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M31 Globular Cluster Structures and the Presence of X-Ray Binaries
Barmby, P.; Agar, J. R. R.
The Andromeda galaxy, M31, has several times the number of globular clusters found in the Milky Way. It contains a correspondingly larger number of low-mass X-ray binaries (LMXBs) associated with globular clusters, and as such can be used to investigate the cluster properties that lead to X-ray binary formation. The best tracer of the spatial stru…
Local Variability in the Orbit of Saturn's F Ring
Cooper, N. J.; Murray, C. D.; Williams, G. A.
We present an analysis of the orbit of Saturn's F ring using images recorded by the Imaging Science Subsystem of the Cassini spacecraft. A total of 9805 observations have been made from 10 image sequences obtained between 2006 November 23 and 2009 July 28. Each sequence of up to 240 images spans a single orbit of the F ring, allowing 10 independen…
Statistical Study of 2XMMi-DR3/SDSS-DR8 Cross-correlation Sample
Zhao, Yong-Heng; Wu, Xue-Bing; Zhou, Xin-Lin +1 more
Cross-correlating the XMM-Newton 2XMMi-DR3 catalog with the Sloan Digital Sky Survey (SDSS) Data Release 8, we obtain one of the largest X-ray/optical catalogs and explore the distribution of various classes of X-ray emitters in the multidimensional photometric parameter space. Quasars and galaxies occupy different zones while stars scatter in the…
Binary Star Synthetic Photometry and Distance Determination Using BINSYN
Linnell, Albert P.; Hubeny, Ivan; DeStefano, Paul
This paper extends synthetic photometry to components of binary star systems. The paper demonstrates accurate recovery of single star photometric properties for four photometric standards, Vega, Sirius, GD153, and HD209458, ranging over the HR diagram, when their model synthetic spectra are placed in fictitious binary systems and subjected to synt…
XMM-Newton Observations of Luminous Sources in Nearby Galaxies NGC 4395, NGC 4736, and NGC 4258
Balman, S.; Akyuz, A.; Sonbas, E. +3 more
We present the results of a study of non-nuclear discrete sources in a sample of three nearby spiral galaxies (NGC 4395, NGC 4736, and NGC 4258) based on XMM-Newton archival data supplemented with Chandra data for spectral and timing analyses. A total of 75 X-ray sources have been detected within the D 25 regions of the target galaxies.…
Investigating the Core Morphology-Seyfert Class Relationship with Hubble Space Telescope Archival Images of Local Seyfert Galaxies
Kim, Hwihyun; Rutkowski, M. J.; Windhorst, R. A. +2 more
The unified model of active galactic nuclei (AGNs) has provided a successful explanation for the observed diversity of AGNs in the local universe. However, recent analysis of multi-wavelength spectral and image data suggests that the unified model is only a partial theory of AGNs, and may need to be augmented to remain consistent with all observat…
Far-ultraviolet Spectroscopy of the Nova-like Variable KQ Monocerotis: A New SW Sextantis Star?
Bond, Howard E.; Sion, Edward M.; Wolfe, Aaron
New optical spectra obtained with the SMARTS 1.5 m telescope and archival International Ultraviolet Explorer (IUE) far-ultraviolet (FUV) spectra of the nova-like variable KQ Mon are discussed. The optical spectra reveal Balmer lines in absorption as well as He I absorption superposed on a blue continuum. The 2011 optical spectrum is similar to the…
Relative Photometry of HAT-P-1b Occultations
Winn, Joshua N.; Gilliland, Ronald L.; Bakos, Gáspár Á. +4 more
We present Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph observations of two occultations of the transiting exoplanet HAT-P-1b. By measuring the planet to star flux ratio near opposition, we constrain the geometric albedo of the planet, which is strongly linked to its atmospheric temperature gradient. An advantage of HAT-P-1 as…
Efficient Selection and Classification of Infrared Excess Emission Stars Based on AKARI and 2MASS Data
Zeng Li, Jin; Rector, Travis A.; Huang, Ya Fang +1 more
The selection of young stellar objects (YSOs) based on excess emission in the infrared is easily contaminated by post-main-sequence stars and various types of emission line stars with similar properties. We define in this paper stringent criteria for an efficient selection and classification of stellar sources with infrared excess emission based o…
Twenty-five Subarcsecond Binaries Discovered by Lunar Occultations
Cusano, F.; Richichi, A.; Fors, O. +1 more
We report on 25 subarcsecond binaries, detected for the first time by means of lunar occultations in the near-infrared (near-IR) as part of a long-term program using the ISAAC instrument at the ESO Very Large Telescope. The primaries have magnitudes in the range K = 3.8-10.4, and the companions in the range K = 6.4-12.1. The magnitude differences …