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Monitoring of the optical and 2.5-11.7 mu m spectrum and mid-IR imaging of the Seyfert 1 galaxy Mrk 279 with ISO
Altieri, B.; Malkan, M. A.; Clavel, J. +29 more
Mid-infrared images of the Seyfert 1 galaxy
HST NICMOS photometry of the reddened bulge globular clusters NGC 6528, Terzan 5, Liller 1, UKS 1 and Terzan 4
Zoccali, M.; Rich, R. M.; Bica, E. +4 more
We present results from NICMOS Hubble Space Telescope observations of the reddened bulge globular clusters NGC 6528, Terzan 5, Liller 1, UKS 1 and Terzan 4, obtained through the filters F110W (1.1 mu m) and F160W (1.6 mu m) (nearly equivalent to J and H). For the first time the turnoff region of Liller 1 and the main sequence of Terzan 5 and Terza…
New Constraints on Protostellar Jet Collimation from High-Density Gas UV Tracers
Gómez de Castro, Ana I.; Verdugo, Eva
The analysis of high-resolution profiles of the semiforbidden UV lines of C III]1908 and Si III]1892 in the spectra of T Tauri stars (TTSs) shows the following: (1) There is C III]1908 and Si III]1892 emission at velocities that are similar to those observed in the optical forbidden lines formed in the T…
Positions for the Outer Planets and Many of Their Satellites. V. FASTT Observations Taken in 2000-2001
Stone, Ronald C.
As part of an ongoing observing program with the Flagstaff Astrometric Scanning Transit Telescope (FASTT), this paper presents 1084 new equatorial positions taken in 2000-2001 for the outer planets Uranus, Neptune, and Pluto, as well as for 17 satellites of Jupiter-Neptune. All the positions were determined using differential reductions with refer…
High-Resolution Spectroscopic Observations of Hipparcos Red Clump Giants: Metallicity and Mass Determinations
Zhao, G.; Mao, Shude; Qiu, H. M.
We obtain high-resolution and high signal-to-noise ratio spectra of 39 red clump giants selected from the Hipparcos Catalogue. We determine their atmospheric parameters, iron abundances, α-element enhancements, and masses. We find that the sample can be divided into a metal-poor group and a metal-rich group. The majority of the stars are metal-ric…
K-Band Spectroscopy of Compact Star Clusters in NGC 4038/4039
Lehnert, Matthew D.; Genzel, Reinhard; Thatte, Niranjan +2 more
Integral field spectroscopy in the K band (1.9-2.4 µm) was performed on four IR-bright star clusters and the two nuclei in NGC 4038/4039 (``the Antennae''). Two of the clusters are located in the overlap region of the two galaxies and together comprise ~25% of the total 15 µm emission of the total 4.8 GHz emission from this pair of mer…
A Two-Dimensional Alfvén-Wave-Driven Solar Wind Model
Chen, Y.; Hu, Y. Q.
This paper presents a two-dimensional, Alfvén-wave-driven solar wind model, in which the wave energy is assumed to cascade from the low-frequency Alfvén waves to high-frequency ion cyclotron waves and to be transferred to the solar wind protons by cyclotron resonance at the Kolmogorov rate. A typical structure in the meridional plane consisting of…
Neptune's Atmospheric Circulation and Cloud Morphology: Changes Revealed by 1998 HST Imaging
Baines, K. H.; Sromovsky, L. A.; Fry, P. M. +2 more
On 11-12 August 1998, we imaged Neptune using the Hubble Space Telescope WFPC2 CCD camera and NICMOS InSb camera to obtain high-spatial-resolution, absolutely calibrated imagery from the visible through the near infrared. We used nine HST orbits to intensively sample one rotation of Neptune, and four additional orbits to sample cloud evolution and…
Spectroscopic binary orbits from ultraviolet radial velocities. Paper 31: Stars with few IUE observations
Stickland, D. J.; Lloyd, C.
All O-type stars known to be or suspected of being binary, and which have short-wavelength high-resolution IUE observations, but which have not yet been dealt with in the present series, have been examined for velocity variability, in both the UV and optical. Several new orbital solutions are suggested.
Spectropolarimetric measurements of the mean longitudinal magnetic field of chemically peculiar stars. II. Phase relating the magnetic and luminosity variabilities
Leone, F.; Catanzaro, G.
For a sample of chemically peculiar stars, we report time-resolved measurements of the effective magnetic field which were obtained with the spectropolarimetry operating at the Catania Astrophysical Observatory. These observations are combined with data from the literature for better pointing out that periodic magnetic variability which characteri…