Search Publications
Solar wind measurements with SOHO: The CELIAS/MTOF proton monitor
Hsieh, K. C.; Wurz, P.; Bochsler, P. +26 more
The proton monitor, a small subsensor in the Charge, Element, and Isotope Analysis System/Mass Time-of-Flight (CELIAS/MTOF) experiment on the SOHO spacecraft, was designed to assist in the interpretation of measurements from the high mass resolution main MTOF sensor. In this paper we demonstrate that the proton monitor data may be used to generate…
Nuclear stellar discs in early-type galaxies - II. Photometric properties
van den Bosch, Frank C.; Scorza, Cecilia
Hubble Space Telescope images of two early-type galaxies harbouring both nuclear and outer stellar discs are studied in detail. By means of a photometric decomposition, the images of NGC 4342 and 4570 are analysed and the photometric properties of the nuclear discs investigated. We find a continuity of properties in the parameter space defined by …
The EC 14026 stars - VII. PG 1605+072, a star with many pulsation modes
O'Donoghue, D.; Kilkenny, D.; Lynas-Gray, A. E. +3 more
We report the discovery of large-amplitude (~0.25 mag) pulsations in the bright (V=12.8) sdB star, PG 1605+072. The dominant period is 480s, but more than 20 periods were present on at least three separate occasions. Frequency analysis of the complete data set yields more than 30 periods. A few of these are harmonics or linear combinations of the …
Spiral Galaxies with WFPC2. III. Nuclear Cusp Slopes
Carollo, C. M.; Stiavelli, M.
In this paper, the third of a series dedicated to the investigation of the nuclear properties of spiral galaxies, we (1) model the Wide Field Planetary Camera 2 F606W nuclear surface brightness profiles of 41 spiral galaxies presented in Papers I and II with the analytic law introduced by Lauer et al. and (2) deconvolve these surface brightness pr…
The Extragalactic Distance Scale Key Project. V. Photometry of the Brightest Stars in M100 and the Calibration of WFPC2
Illingworth, Garth D.; Madore, Barry F.; Freedman, Wendy L. +18 more
We present multiepoch VI observations of the brightest stars in the Virgo spiral galaxy M100 obtained with the WFPC2 aboard the Hubble Space Telescope. Particular attention has been given to the WFPC2 calibration process, and a new calibration is presented here. We find that a calibration based on short exposure (t <= 60 sec) observations of th…
Detection of methyl radicals (CH_3) on Saturn
Encrenaz, T.; Feuchtgruber, H.; Moses, J. I. +1 more
We report the first detection of methyl radicals (CH_3) in the upper atmosphere of
Thermal coupling of protons and neutral hydrogen in the fast solar wind
Habbal, Shadia R.; Allen, Lorraine A.; Hu, You Q.
We investigate the coupling between neutral hydrogen atoms and protons in the corona for a range of proton temperatures reaching a maximum of 6×106K, as recently inferred from observations of the Ly α spectral line profiles by Kohl et al. [1996]. We adopt the approach used by Olsen et al. [1994], whereby the neutral hydrogen atoms are t…
First Measurement of the Submillimeter Sunyaev-Zeldovich Effect
Bock, J. J.; Giard, M.; Pajot, F. +10 more
We report the first detection of the Sunyaev-Zeldovich (S-Z) increment on the cosmic microwave background at submillimeter wavelengths in the direction of a cluster of galaxies. It was achieved toward the rich cluster Abell 2163, using the PRONAOS 2 m stratospheric telescope. Together with data from the SuZIE, Diabolo, and ISO-PHT experiments, the…
Kinetic properties of solar wind minor ions and protons measured with SOHO/CELIAS
Wurz, P.; Bochsler, P.; Geiss, J. +14 more
Using observations of the Charge Time-of-Flight (CTOF) charge and mass spectrometer of the Charge, Element and Isotope Analysis System (CELIAS), and of CELIAS/proton monitor on board the Solar and Heliospheric Observatory (SOHO), we present an overview of speeds and kinetic temperatures of minor ions and protons in the solar wind near solar minimu…
The Very Highly Ionized Broad Absorption Line System of the QSO SBS 1542+541
Green, Richard F.; Kriss, Gerard A.; Zheng, Wei +2 more
We have analyzed the broad absorption line system of the bright (V ~ 16.5) high-redshift (z = 2.361) QSO SBS 1542+541 using UV spectra from the Hubble Space Telescope Faint Object Spectrograph, along with optical data from the Multiple Mirror Telescope and the Steward Observatory 2.3 m telescope. These spectra offer continuous wavelength coverage …