Search Publications

Fast ejecta during the ascending phase of solar cycle 23: ACE observations, 1998-1999
DOI: 10.1029/2000JA000214 Bibcode: 2001JGR...10620957B

Webb, D. F.; Burlaga, L. F.; Zurbuchen, T. H. +3 more

We discuss fast ejecta observed at 1 AU during a period of increasing solar activity from February 5, 1998, to November 29, 1999. ``Fast ejecta'' are transient, noncorotating flows that move past the Earth during a day or more, with a maximum speed >600 km s-1. We identify two classes of fast ejecta at 1 AU: (1) magnetic clouds, whos…

2001 Journal of Geophysical Research
SOHO 146
The relationship between star formation rates and mid-infrared emission in galactic disks
DOI: 10.1051/0004-6361:20010498 Bibcode: 2001A&A...372..427R

Roussel, H.; Sauvage, M.; Vigroux, L. +1 more

The Hα and mid-infrared mean disk surface brightnesses are compared in a sample of nearby spirals observed by ISOCAM. This shows that, in spiral disks, dust emission at 7 and 15 mu m provides a reasonable star formation tracer. The fact that the 15 to 7 mu m flux ratio is nearly constant in various global exciting conditions indicates a common ori…

2001 Astronomy and Astrophysics
ISO 146
On the nature of the transition region from the chromosphere to the corona of the Sun
DOI: 10.1051/0004-6361:20010697 Bibcode: 2001A&A...374.1108P

Peter, H.

One of the keys to understand coronal heating is to understand the (magnetic) structure of the atmosphere below the respective coronal features. The EUV emission lines formed in the thin transition region from the chromosphere to the corona present a sensitive tool to study the structure and dynamics of the lowermost corona and its connection to t…

2001 Astronomy and Astrophysics
SOHO 146
A Chandra X-Ray Study of NGC 1068. I. Observations of Extended Emission
DOI: 10.1086/321561 Bibcode: 2001ApJ...556....6Y

Young, A. J.; Wilson, A. S.; Shopbell, P. L.

We report subarcsecond-resolution X-ray imaging spectroscopy of the archetypal type 2 Seyfert galaxy NGC 1068 with the Chandra X-Ray Observatory. The observations reveal the detailed structure and spectra of the 13 kpc extent nebulosity previously imaged at lower resolution with ROSAT. The Chandra image shows a bright, compact source coincident wi…

2001 The Astrophysical Journal
eHST 145
The afterglow of the short/intermediate-duration gamma-ray burst GRB 000301C: A jet at z=2.04
DOI: 10.1051/0004-6361:20010291 Bibcode: 2001A&A...370..909J

Greiner, J.; Cline, T.; Hurley, K. +23 more

We present Ulysses and NEAR data from the detection of the short or intermediate duration (2 s) gamma-ray burst GRB 000301C (2000 March 1.41 UT). The gamma-ray burst (GRB) was localised by the Inter Planetary Network (IPN) and RXTE to an area of ~50 arcmin2. A fading optical counterpart was subsequently discovered with the Nordic Optica…

2001 Astronomy and Astrophysics
Ulysses 145
Near-Infrared Integral Field Spectroscopy and Mid-Infrared Spectroscopy of the Starburst Galaxy M82
DOI: 10.1086/320546 Bibcode: 2001ApJ...552..544F

Lutz, D.; Förster Schreiber, N. M.; Genzel, R. +2 more

We present new infrared observations of the central regions of the starburst galaxy M82. The observations consist of near-infrared integral field spectroscopy in the H and K bands obtained with the MPE 3D instrument and of λ=2.4-45 µm spectroscopy from the Short Wavelength Spectrometer (SWS) onboard the Infrared Space Observatory. These meas…

2001 The Astrophysical Journal
ISO 144
First Results from the Anglo-Australian Planet Search: A Brown Dwarf Candidate and a 51 Peg-like Planet
DOI: 10.1086/320097 Bibcode: 2001ApJ...551..507T

Butler, R. Paul; Vogt, Steven S.; Henry, Gregory W. +5 more

We report results from the Anglo-Australian Planet Search, a survey for planets around 200 solar-type stars in the southern hemisphere that is being carried out on the 3.9 m Anglo-Australian Telescope. Limiting Doppler precisions of 3 m s-1 have been demonstrated from the first 2.5 years of operation, making this the highest-precision planet searc…

2001 The Astrophysical Journal
Hipparcos 144
Abundant molecular gas in tidal dwarf galaxies: On-going galaxy formation
DOI: 10.1051/0004-6361:20011109 Bibcode: 2001A&A...378...51B

Duc, P. -A.; Braine, J.; Charmandaris, V. +4 more

We investigate the process of galaxy formation as can be observed in the only currently forming galaxies - the so-called Tidal Dwarf Galaxies, hereafter TDGs - through observations of the molecular gas detected via its CO (Carbon Monoxide) emission. These objects are formed of material torn off of the outer parts of a spiral disk due to tidal forc…

2001 Astronomy and Astrophysics
eHST 144
Chandra Exposes the Core-collapsed Globular Cluster NGC 6397
DOI: 10.1086/338499 Bibcode: 2001ApJ...563L..53G

Heinke, C. O.; Cool, A. M.; Grindlay, J. E. +2 more

We report results of the Chandra deep-imaging observation of the closest post-core-collapse globular cluster, NGC 6397. Some 25 sources are detected within 2' of the cluster center, of which ~20 are likely cluster members, with LX>~3×1029 ergs s-1. The X-ray spectra suggest identifications with one quiescent low…

2001 The Astrophysical Journal
eHST 143
Soft X-ray emission lines from a relativistic accretion disk in MCG -6-30-15 and Mrk 766
DOI: 10.1051/0004-6361:20000209 Bibcode: 2001A&A...365L.140B

Kaastra, J. S.; Sako, M.; Page, M. J. +3 more

XMM-Newton Reflection Grating Spectrometer (RGS) spectra of the Narrow Line Seyfert 1 galaxies MCG -6-30-15 and Mrk 766 are physically and spectroscopically inconsistent with standard models comprising a power-law continuum absorbed by either cold or ionized matter. We propose that the remarkably similar featu…

2001 Astronomy and Astrophysics
XMM-Newton 143