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A Multiwavelength Catalog of Seyfert 2 Galaxies Observed in the 2--10 keV Energy Band
Malaguti, G.; Bassani, L.; Polletta, M. +2 more
This paper is a catalog of Seyfert 2 galaxies observed in the 2-10 keV band (339 flux entries). In total, it contains data on 150 objects; for 76 objects, a positive detection is reported, while for the remaining sources, 2 σ upper limits to the X-ray emission are given. Most of the data have been collected from the literature over a period starti…
Galaxy Dark Matter: Galaxy-Galaxy Lensing in the Hubble Deep Field
Tyson, J. Anthony; dell'Antonio, Ian P.
In this Letter we present calibrated observations of the average mass of galaxies with 22 < I < 25 in the Hubble Deep Field. We measure the mean mass profile using the statistical gravitational lens distortion of faint blue background galaxies, based on 2221 foreground-background pairs. The observed weak lensing distortion is calibrated via …
The Leo II Dwarf Spheroidal - an Old Galaxy With a Large Intermediate-age Population
Rich, R. Michael; Mighell, Kenneth J.
Deep F555W (broadband V) and F814W (broadband I) observations have been obtained of the Leo II dwarf spheroidal galaxy with the Hubble Space Telescope Wide Field Planetary Camera 2 instrument. The resulting color- magnitude diagrams reach V = 27.4 mag and I = 26.6 mag, and the fiducial sequence has a main-sequence turnoff at V = 25.1 mag. A metall…
Redshift Z approximately 1 Field Galaxies Observed with the Keck Telescope and the Hubble Space Telescope
Illingworth, Garth D.; Forbes, Duncan A.; Davis, Marc +10 more
We report results based on 35 new spectroscopic redshifts obtained with the Keck Telescope for field galaxies that also have photometry and morphology from survey images taken by the refurbished Hubble Space Telescope. A sample of 24 redshifts for galaxies fainter than I = 22 has a median redshift of z ~ 0.81. This result is inconsistent with the …
A detached dust shell surrounding the J-type carbon star Y Canum Venaticorum.
Waters, L. B. F. M.; Kawara, K.; Izumiura, H. +2 more
This paper reports the first clear detection of a detached dust shell surrounding the prototypical J-type carbon star Y CVn in 90µm and 160µm maps taken with the ISO/ISOPHOT. The projected inner radius of the shell is 180"-190", corresponding to (6.4-7.1)x10^17^cm at a distance of 250pc. The shell thickness is obtained to be (2-5)x10^1…
The photometric calibration of the ISO Short Wavelength Spectrometer.
Lutz, D.; Heras, A. M.; Waters, L. B. F. M. +29 more
We give an overview of the photometric calibration of the Short Wavelength Spectrometer (SWS) through the Performance Verification phase. The basic strategy for deriving absolute flux densities from detector output for the grating and Fabry-Perot sections of SWS is reviewed, and the results are demonstrated with 2.4 - 45µm spectra of represe…
Planetary nebulae in the Magellanic Clouds. I. Carbon abundances and TypeI PNe.
Dennefeld, M.; Leisy, P.
We present optical and ultraviolet spectroscopic observations of planetary nebulae (PNe) in the Large (LMC) and the Small Magellanic Clouds (SMC). For the visible spectra with highest S/N, line intensities have been measured to a few tenths of a percent of Hbeta_. UV spectra are used for the determination of carbon abundances. This pape…
Goddard High-Resolution Spectrograph Observations of Procyon and HR 1099
Harper, Graham M.; Wood, Brian E.; Linsky, Jeffrey L. +1 more
Goddard High Resolution Spectrograph (GHRS) observations have revealed the presence of broad wings in the transition-region lines of AU Mic and Capella. It has been proposed that these wings are signatures of microflares in the transition regions of these stars and that the solar analog for this phenomenon might be the "transition region explosive…
Constraints on high-speed solar wind structure near its coronal base: a ULYSSES perspective.
Phillips, J. L.; Wang, Y. -M.; Feldman, W. C. +1 more
Ulysses plasma data at high heliographic latitudes were studied to develop constraints on the structure of the corona at the base of the high-speed solar wind. Salient features of the flow poleward of +/-60° revealed: 1) low variances of all bulk flow parameters, 2) parameter values that agree with those measured during high-speed conditions in th…
Solar Wind Magnetic Field Bending of Jovian Dust Trajectories
Forsyth, R.; Hamilton, D. P.; Phillips, J. L. +5 more
From September 1991 to October 1992, the cosmic dust detector on the Ulysses spacecraft recorded 11 short bursts, or streams, of dust. These dust grains emanated from the jovian system, and their trajectories were strongly affected by solar wind magnetic field forces. Analyses of the on-board measurements of these fields, and of stream approach di…