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An XMM-Newton Observation of the Drifting Pulsar B0943+10
Pavlov, George G.; Zhang, Bing; Sanwal, Divas
Radio pulsar subpulse drifting has been interpreted as rotation of subbeams (sparks) of pair plasma produced by intermittent breakdowns of an inner vacuum gap above the pulsar polar cap. This model also predicts strong thermal X-ray emission from the polar cap caused by inflowing particles created in spark discharges. We have observed the best-stu…
Space Telescope Imaging Spectrograph Ultraviolet Spectra of Large Magellanic Cloud Planetary Nebulae: A Study of Carbon Abundances and Stellar Evolution
Gilmore, Diane; Shaw, Richard A.; Stanghellini, Letizia
We acquired spectra of 24 LMC planetary nebulae (PNs) in the 1150-3000 Å range in order to determine carbon and other ionic abundances. The sample more than doubles the number of LMC PNs with high-quality UV spectra in this wavelength range and whose optical images are available in the Hubble Space Telescope archive. The Space Telescope Imaging Sp…
Rapid Dissipation of Primordial Gas from the AU Microscopii Debris Disk
Weinberger, Alycia J.; Redfield, Seth; Roberge, Aki +1 more
The disk around AU Microscopii, an M1 star in the β Pictoris moving group, is extraordinarily well suited for comparison with the β Pic debris disk (type A5 V). We use far-UV absorption spectroscopy of AU Mic to probe its edge-on disk for small amounts of H2, the primary constituent of gas giant planets. Our conservative upper limit on …
Rotating Molecular Gas Associated with a Silhouette Disk at the Center of the Radio Galaxy 3C 31
Kohno, K.; Nakanishi, K.; Okuda, T. +1 more
Aperture synthesis observations of 12CO(J=1-0) emissions of the radio galaxy 3C 31 (NGC 383) have been made using the Nobeyama Millimeter Array (NMA) and the RAINBOW interferometer (NMA plus the Nobeyama 45 m radio telescope). Our high-resolution (1.9"×1.4", or 640pc×470pc, at D=70 Mpc) 12CO image shows a circularly rotating …
Comparison of Interplanetary CME Charge State Composition with CME-associated Flare Magnitude
Reinard, A.
This paper describes a study of the charge state composition of interplanetary coronal mass ejection (ICME) ejecta in the heliosphere within the context of remote-sensing CME observations at the Sun. First, CME-ICME pairs are examined to determine if a given CME is associated with a flare event. Then, for each ICME, the charge states, O+7
Halos of Spiral Galaxies. II. Halo Metallicity-Luminosity Relation
Ferguson, H. C.; Rich, R. M.; Mouhcine, M. +2 more
Using the Hubble Space Telescope, we have resolved individual red giant branch stars in the halos of eight nearby spiral galaxies. The fields lie at projected distances between 2 and 13 kpc along the galaxies' minor axes. The data set allows a first look at the systematic trends in halo stellar populations. We have found that bright galaxies tend …
The Magnetic Structure of Filament Barbs
Moon, Yong-Jae; Chae, Jongchul; Park, Young-Deuk
There is a controversy about how features protruding laterally from filaments, called barbs, are magnetically structured. On 2004 August 3, we observed a filament that had well-developed barbs. The observations were performed using the 10 inch refractor of the Big Bear Solar Observatory. A fast camera was employed to capture images at five differe…
Hubble Space Telescope ACS Weak-Lensing Analysis of the Galaxy Cluster RDCS 1252.9-2927 at z = 1.24
Ford, H. C.; Demarco, R.; Rosati, P. +12 more
We present a weak-lensing analysis of one of the most distant massive galaxy clusters known, RDCS 1252.9-2927, at z=1.24, using deep images from the Advanced Camera for Surveys (ACS) on board the Hubble Space Telescope (HST). By taking advantage of the depth and angular resolution of the ACS images, we detect for the first time at z>1 a clear w…
Halos of Spiral Galaxies. III. Metallicity Distributions
Ferguson, H. C.; Rich, R. M.; Mouhcine, M. +2 more
We report results of a campaign to image the stellar populations in the halos of highly inclined spiral galaxies, with the fields roughly 10 kpc (projected) from the nuclei. We use the F814W (I) and F606W (V) filters in the Wide Field Planetary Camera 2 on board the Hubble Space Telescope. We unambiguously resolve the stellar halos 1 to 2 mag fain…
Space Telescope Imaging Spectrograph Ultraviolet/Optical Spectroscopy of ``Warm'' Ultraluminous Infrared Galaxies
Veilleux, S.; Sanders, D. B.; Surace, J. A. +2 more
We present high spatial resolution ultraviolet and optical spectroscopy, obtained using the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope, of nuclear structures within four ``warm'' ultraluminous infrared galaxies (ULIRGs). We find an active galactic nucleus (AGN) in at least three and probably all four in our sample, ho…