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FUSE Measurements of Far-Ultraviolet Extinction. I. Galactic Sight Lines
Gordon, Karl D.; Sofia, Ulysses J.; Snow, Theodore P. +8 more
We present extinction curves that include data down to far-ultraviolet wavelengths (FUV; 1050-1200 Å) for nine Galactic sight lines. The FUV extinction was measured using data from the Far Ultraviolet Spectroscopic Explorer. The sight lines were chosen for their unusual extinction properties in the infrared through the ultraviolet; that they probe…
Metal Abundances in a Damped Lyα System along Two Lines of Sight at z = 0.93
Wisotzki, Lutz; Gregg, Michael D.; Lopez, Sebastian +3 more
We study metal abundances in the z=0.9313 damped Lyα system observed along the two lines of sight, A and B, toward the gravitationally lensed double QSO HE 0512-3329. Spatially resolved Space Telescope Imaging Spectrograph spectra constrain the neutral-gas column density to be N(HI)=1020.5 cm-2 in both A and B. UV-visual Eche…
The INTEGRAL/IBIS Source AX J1838.0-0655: A Soft X-Ray-to-TeV γ-Ray Broadband Emitter
Walter, R.; Bird, A. J.; Ubertini, P. +8 more
We report on INTEGRAL observations of AX J1838.0-0655, one of the unidentified objects listed in the first IBIS/ISGRI survey catalog and located in the Scutum arm region. This object, detected in the 20-300 keV band at a confidence level of 15.3 σ (9 × 10-11 ergs cm-2 s-1), is the likely counterpart of the still un…
The XMM-Newton Detection of Diffuse Inverse Compton X-Rays from Lobes of the FR II Radio Galaxy 3C 98
Isobe, N.; Makishima, K.; Tashiro, M. +1 more
The XMM-Newton observation of the nearby FR II radio galaxy 3C 98 is reported. In two exposures on the target, faint diffuse X-ray emission associated with the radio lobes was significantly detected together with a bright X-ray active nucleus, of which the 2-10 keV intrinsic luminosity is (4-8)×1042 ergs s-1. The EPIC spectra…
INTEGRAL SPI Observation of the Galactic Central Radian: Contribution of Discrete Sources and Implication for the Diffuse Emission
Bouchet, L.; Terrier, R.; Diehl, R. +4 more
The INTEGRAL observatory has been performing a deep survey of the Galactic central radian since 2003, with the goal of both extracting a catalog of sources and gaining insight into the Galactic diffuse emission. This paper concentrates on the estimation of the total point-source emission contribution. It is now clear that unresolved point sources …
Disk-integrated Intensity Pseudomodes Measured by SOHO/VIRGO
Jiménez-Reyes, S. J.; García, R. A.; Jiménez, A.
The high-frequency spectrum above the acoustic cutoff frequency (νac) of the solar atmosphere has been observed in velocity measurements at low and high angular degrees and reveals significant evidence for the presence of pseudomodes characterized by their equally spaced signal. In this paper we study this region of the spectra using fo…
Central Blue Clumps in Elliptical Galaxies of the Hubble Ultra Deep Field
Elmegreen, Bruce G.; Elmegreen, Debra Meloy; Ferguson, Thomas E.
Elliptical galaxies larger than 10 pixels in the Hubble Ultra Deep Field (UDF) were surveyed for internal structure; 30 out of 100 in a sample of 884 morphologically classified galaxies exhibit large blue clumps near their centers. Unsharp-masked images of the clearest cases are presented. The distributions of the clumps on color-color and color-m…
Supernova Remnants in the Magellanic Clouds. V. The Complex Interior Structure of the N206 Supernova Remnant
Gruendl, R. A.; Chu, Y. -H.; Guerrero, M. A. +4 more
The N206 supernova remnant (SNR) in the Large Magellanic Cloud has long been considered a prototypical ``mixed morphology'' SNR. Recent observations, however, have added a new twist to this familiar plot: an elongated, radially oriented radio feature seen in projection against the SNR face. Utilizing the high resolution and sensitivity available w…
A Simultaneous RXTE and XMM-Newton Observation of the Broad-Line Radio Galaxy 3C 111
Eracleous, Michael; Gliozzi, Mario; Mushotzky, Richard F. +2 more
We present the results of simultaneous XMM-Newton and RXTE observations of the broad-line radio galaxy 3C 111. We find that the Compton reflection bump is extremely weak; however, broad residuals are clearly present in the spectrum near the Fe Kα emission line region. When fitted with a Gaussian emission line, the feature has an equivalent width o…
The Vela Pulsar in the Ultraviolet
Pavlov, George G.; Kargaltsev, Oleg; Romani, Roger W.
We describe time-tagged observations of the Vela pulsar (PSR B0833-45) with the HST STIS MAMA UV detectors. Using an optimal extraction technique, we obtain an NUV light curve and crude FUV phase-resolved spectra. The pulse is dominated by complex nonthermal emission at all phases. We obtain approximate spectral indices for the brightest pulse com…