Search Publications
Complete Models of Axisymmetric Sunspots: Magnetoconvection with Coronal Heating
Alexander, David; Hurlburt, Neal E.; Rucklidge, Alastair M.
We present detailed results of numerical experiments into the nature of complete sunspots. The models remain highly idealized but include fully nonlinear compressible magnetoconvection in an axisymmetric layer that drives energy into an overlying, low-β plasma. We survey a range of parameters in which the resulting magnetoconvection displays the f…
XMM-Newton observation of the bursting pulsar GRO J1744-28 in quiescence
Goldoni, P.; Decourchelle, A.; Warwick, R. S. +3 more
The XMM-Newton X-ray observatory performed a pointed observation of the bursting pulsar GRO J1744-28 in April 2001 for about 10 ks during a program devoted to the scan of the Galactic center region. After the discovery of this source by BATSE in December 1995 during a very active bursting phase, it has been in quiescence since April 1997. We prese…
The Cassini Ka-band gravitational wave experiments
Tinto, Massimo
Cassini, a joint American/European interplanetary scientific mission to Saturn, will be continuously and coherently tracked for 40 days during its solar oppositions in the next three years, starting on 26 November 2001. Doppler tracking searches for gravitational waves in the millihertz frequency band will be performed by using newly implemented K…
Short vs Long Time Series : Example of the Solar Diameter
Delmas, C.; Laclare, F.
The significance of a time series obviously changes with its length and accuracy; data about the Sun are no exception. In this short paper, we compare the 23-year long series of visual observations of the solar semi-diameter at Calern Observatory with the activity cycle to find an apparent opposing phase. The comparison of the sub-series of the sa…
Correlated multiwavelength emission from the X-ray-bright Seyfert galaxy III Zw 2
Page, M. J.; Stevens, J. A.; Mason, K. O. +8 more
The X-ray-bright Seyfert 1 galaxy III Zw 2 was observed with XMM-Newton in 2000 July. Its X-ray spectrum can be described by a power law of photon index Γ= 1.7 and an extremely broad (FWHM~ 140 000 km s-1) Fe Kα line at 6.44 keV. The iron line has an equivalent width of ~800 eV. To study the long-term X-ray behaviour of the source we ha…
X-Ray Light Curves of Gamma-Ray Bursts Detected with the All-Sky Monitor on RXTE
Hurley, K.; Smith, D. A.; Levine, A. +6 more
We present X-ray light curves (1.5-12 keV) for 15 gamma-ray bursts (GRBs) detected by the All-Sky Monitor (ASM) on the Rossi X-Ray Timing Explorer. We compare these soft X-ray light curves with count rate histories obtained by the high-energy (>12 keV) experiments BATSE, Konus-Wind, the BeppoSAX Gamma-Ray Burst Monitor, and the burst monitor on…
NGC 6994 - clearly not a physical stellar ensemble
Soubiran, C.; Odenkirchen, M.
The sparse stellar ensemble NGC 6994 = M 73 has recently been discussed as a possible remnant of an old open cluster. In order to solve the controversy regarding the nature of this object we have taken high-resolution spectra of the six brightest stars within 6' angular distance of its nominal position. These stars are the only obvious candidate m…
Effect of Flow-Tube Geometry on Solar Wind Properties
Chen, Y.; Hu, Y. Q.
A mathematical description of the solar wind flow-tube geometry is proposed. The expansion factor of the flow tube f(r) (=a/r2, r is the heliocentric distance and a is the flow-tube cross-section area)increases monotonically from 1 at the coronal base to m at rc, and approaches its asymptotic value f∞ ne…
INTEGRAL Field Spectroscopy of IRAS 15206+3342: Gas Inflows and Starbursts in an Advanced Merger
Arribas, Santiago; Colina, Luis
Integral field optical spectroscopy using the INTEGRAL system (complemented with Hubble Space Telescope WFPC2 imaging) is used to characterize the kinematic and ionization properties of the warm ionized gas in the ultraluminous infrared galaxy IRAS 15206+3342. These data present kinematic and morphological evidence for a tidal tail connecting the …
Asteroid (216) Kleopatra. Tests of the radar-derived shape model
Lattanzi, M.; Tanga, P.; Berthier, J. +5 more
The shape model of Ostro et al. (\cite{ostro00}) for