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The NICMOS Polarimetric Calibration
Axon, D.; Batcheldor, D.; Sparks, W. +3 more
An accurate knowledge of the absolute calibration of the polarizing elements in the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) becomes especially important when conducting studies that require measuring degrees of polarization of close to 1% in the near-infrared. We present a comprehensive study of all previously observed polarime…
Variable Unidentified Emission near 6307 Å in η Carinae
Weis, K.; Stahl, O.; Davidson, K. +2 more
We have discovered a conspicuous unidentified variable feature near 6307 Å in the spectrum of η Carinae that is spatially unresolved from the central star and its wind (r<~200-300 AU). It is significant for two reasons: first, such prominent unidentified lines are now rare in this object, and second, this feature varies strongly and systematica…
DDO 44 and UGC 4998: Distances, Metallicities, and Star Formation Histories
Mateo, Mario; Aparicio, Antonio; Alonso-García, Javier
We have obtained deep HST imaging of two candidate dwarf systems in the nearby M81 Group, DDO 44 and UGC 4998. Both are isolated, low surface brightness systems, but with likely very different star formation histories based on their mean colors and color fluctuations. The color-magnitude diagrams of these galaxies have been used to estimate their …
A High-Resolution Spectral Atlas of α Persei from 3810 to 8100 Å
Galazutdinov, G. A.; Lee, Byeong-Cheol; Park, Myeong-Gu +5 more
We present a high-resolution (λ/δλ=90,000) spectral atlas of the F5 Ib star α Per covering the 3810-8100 Å region. The atlas, based on data obtained with the aid of the echelle spectrograph BOES fed by the 1.8 m telescope at Bohyunsan Observatory (Korea), is the result of the co-addition of a few well-exposed spectra. The final signal-to-noise rat…
Exploring the Potential of Integral Field Spectroscopy for Observing Extrasolar Planet Transits: Ground-based Observations of the Atmospheric Na in HD 209458b
Arribas, Santiago; Sparks, William B.; Gilliland, Ronald L. +3 more
We explore the use of integral field spectroscopy (IFS) for observing extrasolar planet transits. Although this technique should find its full potential in space-based observations (e.g., James Webb Space Telescope, Terrestrial Planet Finder), we have tested its basics with ground-based time-series observations of HD 209458b obtained with the Will…
Theoretical Isochrones with Extinction in the K Band. II. J - K versus K
Lee, Myung Gyoon; Figer, Donald F.; Kim, Sungsoo S.
We calculate theoretical isochrones in a consistent way for five filter pairs near the J and K band atmospheric windows (J-K, J-K', J-Ks, F110W-F205W, and F110W-F222M) using the Padova stellar evolutionary models of Girardi et al. We present magnitude transformations between various K-band filters as a function of color. Isoc…
Productivity and Impact of Space-based Astronomical Facilities
Trimble, Virginia; Zaich, Paul; Bosler, Tammy
In 2001, 18 journals published about 1270 astronomical papers that reported and/or analyzed data gathered by space-based observatories and missions. These papers were cited 24,460 times in papers published in 2002-2004, an average of 19.26 citations per paper or 6.42 citations per paper per year (sometimes called impact or impact factor). About 60…
Cepheids in Multiple Systems: ADS 14859
Evans, Nancy Remage; Karovska, Margarita; Massa, Derck +3 more
We have attempted to resolve the system containing the Cepheid V1334 Cyg (=ADS 14859) using both the Faint Object Camera (FOC) and the Fine Guidance Sensor (FGS) on the Hubble Space Telescope, and also using ground-based speckle interferometry with 4 m class instruments. None of these approaches was successful, leading to upper limits of approxima…
Proper Motions of Faint Ultraviolet-bright Sources in the Sandage Two-Color Survey of the Galactic Plane
Lépine, Sébastien; Lanning, Howard H.
Proper motions with values >=10 or <=-10 mas yr-1 have been extracted from the USNO-B1.0 and Tycho-2 catalogs for all Lanning UV-bright sources identified in the Sandage Two-Color Survey of the Galactic Plane and presented in Papers I-VI. Of the 572 sources examined, we find at least 213 that exhibit a significantly large proper m…
Multiwavelength Analyses of Faint Infrared Galaxies
Berta, Stefano
The present work follows a chronological outline covering the development of infrared space facilities in recent decades. The Infrared Astronomical Satellite (launched in 1984), Infrared Space Observatory (1995), and Spitzer Space Telescope (2003 August) constitute a logical sequence in the study of galactic infrared properties, with a well-modula…