Search Publications
Solar Neutrino Emission Deduced from a Seismic Model
Kosovichev, A. G.; Christensen-Dalsgaard, J.; García, R. A. +10 more
Three helioseismic instruments on the Solar and Heliospheric Observatory have observed the Sun almost continuously since early 1996. This has led to detailed study of the biases induced by the instruments that measure intensity or Doppler velocity variation. Photospheric turbulence hardly influences the tiny signature of conditions in the energy-g…
The Frequency of Binary Stars in the Core of 47 Tucanae
Albrow, Michael D.; Sarajedini, Ata; Gilliland, Ronald L. +3 more
Differential time series photometry has been derived for 46,422 main-sequence stars in the core of 47 Tucanae. The observations consisted of near-continuous 160 s exposures alternating between the F555W and F814W filters for 8.3 days in 1999 July with the Wide Field Planetary Camera 2 on the Hubble Space Telescope. Using Fourier and other search m…
Fast ejecta during the ascending phase of solar cycle 23: ACE observations, 1998-1999
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…
The relationship between star formation rates and mid-infrared emission in galactic disks
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…
On the nature of the transition region from the chromosphere to the corona of the Sun
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…
A Chandra X-Ray Study of NGC 1068. I. Observations of Extended Emission
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…
The afterglow of the short/intermediate-duration gamma-ray burst GRB 000301C : A jet at z=2.04
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…
Near-Infrared Integral Field Spectroscopy and Mid-Infrared Spectroscopy of the Starburst Galaxy M82
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…
First Results from the Anglo-Australian Planet Search: A Brown Dwarf Candidate and a 51 Peg-like Planet
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…
Abundant molecular gas in tidal dwarf galaxies: On-going galaxy formation
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…