Search Publications
Analysis of plasmaspheric plumes: CLUSTER and IMAGE observations
Sandel, B. R.; Dandouras, I.; André, M. +13 more
Plasmaspheric plumes have been routinely observed by CLUSTER and IMAGE. The CLUSTER mission provides high time resolution four-point measurements of the plasmasphere near perigee. Total electron density profiles have been derived from the electron plasma frequency identified by the WHISPER sounder supplemented, in-between soundings, by relative va…
Dark and Baryonic Matter in Bright Spiral Galaxies. I. Near-Infrared and Optical Broadband Surface Photometry of 30 Galaxies
de Jong, Roelof S.; Pogge, Richard W.; Kassin, Susan A.
We present photometrically calibrated images and surface photometry in the B, V, R, J, H, and K bands of 25, and in the g, r, and K bands of five nearby bright (B0T<12.5 mag) spiral galaxies with inclinations of 30°-65° spanning the Hubble sequence from Sa to Scd. Data are from The Ohio State University Bright Spiral Galax…
The Araucaria Project: The Distance to NGC 300 from the Red Giant Branch Tip Using HST ACS Imaging
Bresolin, Fabio; Kudritzki, Rolf-Peter; Gieren, Wolfgang +2 more
We have used the Advanced Camera for Surveys on board the Hubble Space Telescope to obtain deep photometry of the NGC 300 spiral galaxy in the Sculptor group. The results have been used to derive an accurate distance determination based on the tip of the red giant branch distance estimator. Both edge-detection and maximum likelihood methods have b…
OB Stars in the Solar Neighborhood. II. Kinematics
Alfaro, E. J.; Cabrera-Caño, J.; Elias, F.
Using the spatial classification method and the structural parameters estimated for the Gould Belt (GB) and the local Galactic disk (LGD) from a previous paper, we have evaluated spatial membership probabilities for a sample of O and B stars from the Hipparcos catalog (Perryman and coworkers) with available proper motions and radial velocity data.…
Equatorial noise: Statistical study of its localization and the derived number density
Maksimovic, M.; de Conchy, Y.; Santolík, O. +5 more
Results of a statistical study of equatorial noise emissions are presented. These electromagnetic emissions are observed in the inner magnetosphere in the vicinity of the geomagnetic equator at frequencies below the lower hybrid frequency. We use the data recorded by four Cluster spacecraft during years 2001-2003. The data set was processed in thr…
Eta Carinae across the 2003.5 Minimum: The Character and Variability of the Ejecta Absorption in the Near-Ultraviolet
Gull, T. R.; Nielsen, K. E.; Kober, G. Vieira
We present Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS) high-resolution near-ultraviolet (NUV) spectra of η Car's central source recorded before, during and after the 2003.5 spectroscopic minimum. Our focus is on the narrow absorption lines formed in multiple circumstellar shells, superimposed on the broad P Cygni stell…
Discovery of a relativistic Fe line in PG 1425+267 with XMM-Newton and study of its short time-scale variability
Fabian, A. C.; Miniutti, G.
We report results from the XMM-Newton observation of the radio-loud quasar PG 1425+267 (z= 0.366). The X-ray data above 2keV exhibit a double-peaked emission feature in the Fe K band. The higher energy peak is found at 6.4keV and is consistent with being narrow, while the lower energy one is detected at 5.3keV and is much broader than the detector…
The OSACA database and a kinematic analysis of stars in the solar neighborhood
Bobylev, V. V.; Bajkova, A. T.; Goncharov, G. A.
We transformed radial velocities compiled from more than 1400 published sources, including the Geneva-Copenhagen survey of the solar neighborhood (CORAVEL-CfA), into a uniform system based on the radial velocities of 854 standard stars in our list. This enabled us to calculate the average weighted radial velocities for more than 25000 HIPPARCOS st…
Hubble Space Telescope Identification of the Optical Counterparts of Ultraluminous X-Ray Sources in M51
Terashima, Yuichi; Wilson, Andrew S.; Inoue, Hirohiko
We present the results of a search for optical identifications of ultraluminous X-ray sources (ULXs) in M51 by using mosaic images taken with the Hubble Space Telescope(HST) Advanced Camera for Surveys (ASC) in filters F435W (B), F555W (V), F814W (I), and F658N (Hα). Our sample, consisting of nine ULXs, is defined by analyzing the three Chandra ob…
Enceladus: A Source of Nitrogen and an Explanation for the Water Vapor Plume Observed by Cassini
Loeffler, M. J.; Raut, U.; Baragiola, R. A.
Recently, the Cassini spacecraft observed an unexpected emission of plumes of water vapor, nitrogen, and icy particles from the southern polar region of Saturn's icy moon Enceladus. While these findings support previous ideas of geological activity in this icy moon, there is no experimental evidence explaining how these plumes could be produced at…