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H i 21 Centimeter Absorption in Two Low-Redshift Damped Lyalpha Systems
Turnshek, D.; Meylan, G.; Smette, A. +3 more
We report the discovery of two low-redshift H i 21 cm absorbers, one at z = 0.2212 toward the z_em = 0.630 quasar OI 363 (B0738+313), and the other at z = 0.3127 toward PKS B1127-145 (z_em = 1.187). Both were found during a survey of Mg ii-selected systems at redshifts 0.2 < z < 1 using the new UHF-high system at the Westerbork Synthesis Rad…
Molecular Gas and Star Formation in the Host Galaxy of the QSO I ZW 1
Tacconi, L. J.; Schinnerer, E.; Eckart, A.
We have investigated the ISM of the I Zw 1 QSO host galaxy with Plateau de Bure millimeter interferometry and high angular resolution near-infrared imaging spectroscopy. We have detected a circumnuclear gas ring of diameter ~1.5" (1.8 kpc) in its millimetric CO line emission and have mapped the disk and the spiral arms of the host galaxy in the
A sample of planetary nebulae observed by HIPPARCOS
Pottasch, S. R.; Jasniewicz, G.; Acker, A. +1 more
By using HIPPARCOS data (magnitudes, parallaxes, proper motions), (1) we determine new values of the apparent luminosity of the central stars of 19 planetary nebulae, (2) we discuss their distance and position on the T/L diagram. By comparison with the distances determined by individual or statistical methods, we see that most of these ``ground" d…
Red Clump Morphology as Evidence against a New Intervening Stellar Population as the Primary Source of Microlensing toward the Large Magellanic Cloud
Beaulieu, Jean-Philippe; Sackett, Penny D.
We examine the morphology of the color-magnitude diagram (CMD) for core helium burning (red clump) stars to test the recent suggestion by Zaritsky & Lin that an extension of the red clump in the Large Magellanic Cloud (LMC) toward brighter magnitudes is the result of an intervening population of stars that is responsible for a significant frac…
FIP Effect in the Solar Upper Atmosphere: Spectroscopic Results
Feldman, U.
Recent spectroscopic measurements from instruments on the Solar and Heliospheric Observatory (SOHO) find that the coronal composition above a polar coronal hole is nearly photospheric. However, similar SOHO observations show that in coronal plasmas above quiet equatorial regions low-FIP elements are enhanced by a factor of ≈ 4. In addition, the pr…
The Mass Distribution in the Elliptical Galaxy NGC 3377: Evidence for a 2 X 10^8 M_⊙ Black Hole
Richstone, Douglas; Kormendy, John; Bender, Ralf +1 more
This paper is a study of the mass distribution in the central 35" ~= 1.7 kpc of the E5 galaxy NGC 3377. Stellar rotation velocity and velocity dispersion profiles (seeing sigma_* = 0.20"-0.56") and V-band surface photometry (sigma_* = 0.20"-0.26") have been obtained with the Canada-France-Hawaii Telescope. NGC 3377 is kinematically similar to M32:…
Oscillations of sunspot magnetic fields
Solanki, S. K.; Scherrer, P. H.; Stenflo, J. O. +2 more
We report on velocity and magnetic field oscillations observed in sunspots using the MDI instrument onboard SOHO. In addition to the well-known velocity oscillations, the data clearly show highly localised oscillations of the magnetogram signal in different parts of the sunspots. We show that only oscillations of the magnetic field vector can prod…
Solar Wind Velocity and Anisotropic Coronal Kinetic Temperature Measured with the O VI Doublet Ratio
Giordano, S.; Antonucci, E.; Martin, R. +1 more
Doppler dimming of the O vi resonance lines (λ1032 Å, λ1037 Å) in an expanding corona is calculated including the pumping effect on the O vi λ1037.61 Å of both C ii lines at λ1036.34 Å and λ1037.02 Å, and the effect of the width of the absorption profiles of the coronal oxygen ions along the incident radiation. The pumping effect of the C ii line …
Three Populous Clusters Discovered in the Large Magellanic Cloud Age Gap
Sarajedini, Ata
In the process of searching the Hubble Space Telescope archive, we have serendipitously discovered three populous Large Magellanic Cloud (LMC) clusters with ages that place them in the LMC ``age gap.'' These clusters-NGC 2155, SL 663, and NGC 2121-turn out to have [Fe/H] ~ -1.0 and ages of ~4 Gyr. This puts them in the ``age gap'' between the inte…
Chromospheric Upflow Events Associated with Transition Region Explosive Events
Wang, Haimin; Chae, Jongchul; Schühle, Udo +2 more
Transition region explosive events are considered to be a manifestation of small-scale magnetic reconnection ubiquitously occurring--even in the quiet Sun. In this paper, we report a close association between transition region explosive events and chromospheric upflow events seen in Hα. From a comparison of the Big Bear Solar Observatory (BBSO) Hα…