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The Formation of a Prominence in Active Region NOAA 8668. I. SOHO/MDI Observations of Magnetic Field Evolution
DOI: 10.1086/322491 Bibcode: 2001ApJ...560..476C

Qiu, Jiong; Wang, Haimin; Chae, Jongchul +3 more

We have studied the evolution of the photospheric magnetic field in active region NOAA 8668 for 3 days while the formation of a reverse S-shaped filament proceeded. From a set of full-disk line-of-sight magnetograms taken by the Michelson Doppler Imager (MDI) on board the Solar and Heliospheric Observatory (SOHO), we have found a large canceling m…

2001 The Astrophysical Journal
SOHO 181
CHIANTI-An Atomic Database for Emission Lines. IV. Extension to X-Ray Wavelengths
DOI: 10.1086/320854 Bibcode: 2001ApJS..134..331D

Young, P. R.; Del Zanna, G.; Dere, K. P. +1 more

CHIANTI provides a database of atomic energy levels, wavelengths, radiative transition probabilities, and electron excitation data for a large number of ions of astrophysical interest. It also includes a suite of Interactive Data Language programs to calculate optically thin synthetic spectra and to perform spectral analysis and plasma diagnostics…

2001 The Astrophysical Journal Supplement Series
SOHO 180
Mayall II=G1 in M31: Giant Globular Cluster or Core of a Dwarf Elliptical Galaxy?
DOI: 10.1086/321166 Bibcode: 2001AJ....122..830M

Djorgovski, S. G.; Jablonka, P.; Sarajedini, A. +3 more

Mayall II=G1 is one of the brightest globular clusters belonging to M31, the Andromeda galaxy. Our observations with the Wide Field and Planetary Camera (WFPC2) on board the Hubble Space Telescope (HST) provide photometric data for the I versus V-I and V versus V-I color-magnitude diagrams. They reach stars with magnitudes fainter than V=27 mag, w…

2001 The Astronomical Journal
eHST 180
A Multiwavelength Study of the Young Star Clusters and Interstellar Medium in the Antennae Galaxies
DOI: 10.1086/322278 Bibcode: 2001ApJ...561..727Z

Whitmore, Bradley C.; Fall, S. Michael; Zhang, Qing

We report on a multiwavelength study of the relationship between young star clusters in the Antennae galaxies (NGC 4038/9) and their interstellar environment, with the goal of understanding the formation and feedback effects of star clusters in merging galaxies. This is possible for the first time because various new observations (from X-rays to r…

2001 The Astrophysical Journal
eHST 180
Near-Sun and near-Earth manifestations of solar eruptions
DOI: 10.1029/2000JA004025 Bibcode: 2001JGR...10625261G

Kaiser, M. L.; Gopalswamy, N.; Bougeret, J. -L. +1 more

We compare the near-Sun and near-Earth manifestations of solar eruptions that occurred during November 1994 to June 1998. We compared white-light coronal mass ejections, metric type II radio bursts, and extreme ultraviolet wave transients (near the Sun) with interplanetary (IP) signatures such as decameter-hectometric type II bursts, kilometric ty…

2001 Journal of Geophysical Research
SOHO 178
Complex resonance absorption structure in the X-ray spectrum of IRAS 13349+2438
DOI: 10.1051/0004-6361:20000081 Bibcode: 2001A&A...365L.168S

Kaastra, J. S.; Clavel, J.; Behar, E. +8 more

The luminous infrared-loud quasar IRAS 13349+2438 was observed with the XMM-Newton Observatory as part of the Performance Verification program. The spectrum obtained by the Reflection Grating Spectrometer (RGS) exhibits broad (v ~ 1400 km s-1 FWHM) absorption lines from highly ionized elements including hydrogen- and …

2001 Astronomy and Astrophysics
XMM-Newton 178
XMM-Newton observations of M 87 and its X-ray halo
DOI: 10.1051/0004-6361:20000092 Bibcode: 2001A&A...365L.181B

Böhringer, H.; Dos Santos, S.; Guainazzi, M. +10 more

We report performance verification observations of the giant elliptical galaxy M 87 in the Virgo Cluster with the MOS, pn, and optical monitor instruments on board of XMM-Newton. With the energy sensitive imaging instruments MOS and pn we obtain the first spatially constrained X-ray spectra of the nucleus and the jet of the galaxy. The good photon…

2001 Astronomy and Astrophysics
XMM-Newton 177
First light measurements with the XMM-Newton reflection grating spectrometers: Evidence for an inverse first ionisation potential effect and anomalous Ne abundance in the Coronae of HR 1099
DOI: 10.1051/0004-6361:20000047 Bibcode: 2001A&A...365L.324B

Kaastra, J. S.; Mewe, R.; Audard, M. +15 more

The RS CVn binary system HR 1099 was extensively observed by the XMM-Newton observatory in February 2000 as its first-light target. A total of 570 ks of exposure time was accumulated with the Reflection Grating Spectrometers (RGS). The integrated X-ray spectrum between 5-35 Å is of unprecedented quality and shows numerous features attributed to tr…

2001 Astronomy and Astrophysics
XMM-Newton 177
Incidence and survival of remnant disks around main-sequence stars
DOI: 10.1051/0004-6361:20000075 Bibcode: 2001A&A...365..545H

Kessler, M. F.; Siebenmorgen, R.; Bouchet, P. +8 more

We present photometric ISO 60 and 170 µm measurements, complemented by some IRAS data at 60 µm, of a sample of 84 nearby main-sequence stars of spectral class A, F, G and K in order to determine the incidence of dust disks around such main-sequence stars. Fifty stars were detected at 60 µm. 36 of these emit a flux expected from t…

2001 Astronomy and Astrophysics
ISO 174
Searching for the Physical Drivers of the Eigenvector 1 Correlation Space
DOI: 10.1086/322286 Bibcode: 2001ApJ...558..553M

Marziani, P.; Zwitter, T.; Sulentic, J. W. +2 more

We recently discussed an Eigenvector 1 (E1) parameter space that provides optimal discrimination between the principal classes of broad-line active galactic nuclei (AGNs). In this paper we begin a search for the most important physical parameters that are likely to govern correlations and data point distribution in E1 space. We focus on the princi…

2001 The Astrophysical Journal
IUE 174