Search Publications
The Dust Ring of Luminous Blue Variable Candidate HD 168625: Infrared Observations and Model Calculations
Ueta, Toshiya; Meixner, Margaret; Bobrowsky, Matthew +2 more
We present a 2.218 µm image from the Hubble Space Telescope/Near Infrared Camera and Multi-Object Spectrometer (NICMOS) and a 55 µm image from ISOPHOT of the dust ring surrounding the luminous blue variable (LBV) candidate HD 168625, together with new temperature and optical depth maps derived from mid-IR images. The shell is detached …
INTEGRAL-RXTE observations of Cygnus X-1
Nowak, M. A.; Rodriguez, J.; Wilms, J. +11 more
We present first results from contemporaneous observations of Cygnus X-1 with INTEGRAL and RXTE, made during INTEGRAL's performance verification phase in 2002 November and December. Consistent with earlier results, the 3-250 keV data are well described by Comptonization spectra from a Compton corona with a temperature of kT ~ 50-90 keV and an opti…
XMM-Newton observations of two hyperluminous IRAS galaxies: Compton-thick quasars with obscuring starbursts
Fabian, A. C.; Crawford, C. S.; Wilman, R. J. +1 more
We present XMM-Newton observations of two hyperluminous IRAS galaxies (LBol > 1013h-250 Lsolar), neither of which were previously detected by ROSAT. Published models of the infrared spectral energy distributions imply that a starburst and obscured quasar contribute equally to the power of e…
A study of RV in Galactic O stars from the 2MASS catalogue
Patriarchi, P.; Perinotto, M.; Morbidelli, L.
We present new measurements of the interstellar reddening parameter RV=AV/E(B-V) towards 185 O stars, using J, H, Ks photometry from the 2MASS project. The results are combined with data from the literature of 95 stars where RV has been derived with the same technique, 22 of which in common with our pres…
Observations of the X-Ray Afterglows of GRB 011211 and GRB 001025 by XMM-Newton
Trudolyubov, Sergey P.; Borozdin, Konstantin N.
We present the XMM-Newton observations of X-ray afterglows of the gamma-ray bursts GRB 011211 and GRB 001025. For GRB 011211, XMM detected a fading X-ray object with an average flux in 0.2-10 keV declining from 2.7×10-13 ergs s-1 cm-2 during the first 5 ks of the 27 ks observation to 1.0×10-13 ergs s
Minimum variance free wave identification: Application to Cluster electric field data in the magnetosheath
Walker, S. N.; Dunlop, M.; Amata, E. +4 more
The electric field measurements provided by the EFW instrument on board Cluster spacecraft are used to identify the mode of plasma waves observed in the magnetosheath. Previous identifications of magnetosheath wave modes have involved either the use of dimensionless transport ratios (DR) calculated using magnetic field and plasma parameters or the…
3C459: a highly asymmetric radio galaxy with a starburst
Muxlow, T. W. B.; Saikia, D. J.; Thomasson, P.
Multifrequency radio observations of the radio galaxy 3C459 using MERLIN, VLA and the EVN and an optical Hubble Space Telescope (HST) image using the F702W filter are presented. The galaxy has a very asymmetric radio structure, a high infrared luminosity and a young stellar population. The eastern component of the double-lobed structure is brighte…
XMM-Newton observations of the nitrogen-rich Wolf-Rayet star WR 1
Oskinova, L. M.; Ignace, R.; Brown, J. C.
We present XMM-Newton results for the X-ray spectrum from the N-rich Wolf-Rayet (WR) star WR 1. The EPIC instrument was used to obtain a medium-resolution spectrum. The following features characterize this spectrum: (a) significant emission ``bumps'' appear that are coincident with the wavelengths of typical strong lines, such as MgXI, SiXIII, and…
ROSAT View of Hipparcos F Stars
Makarov, V. V.; Voges, W.; Suchkov, A. A.
For a set of 11,900 F stars that have uvby photometry and are in the Hipparcos catalog, we have found 1980 X-ray counterparts (~17%) in the ROSAT All-Sky Survey (RASS). In this paper we analyze X-ray properties of these ROSAT F stars and compare that sample with the entire set of our F stars. The comparison has shown that the ROSAT F stars are on …
Gamma-ray bursts observed by the INTEGRAL-SPI anticoincidence shield: A study of individual pulses and temporal variability
Ryde, F.; von Kienlin, A.; Lund, N. +3 more
We study a set of 28 GRB light-curves detected between 15 December 2002 and 9 June 2003 by the anti-coincidence shield of the spectrometer (SPI) of INTEGRAL. During this period it has detected 50 bursts, that have been confirmed by other instruments, with a time resolution of 50 ms. First, we derive the basic characteristics of the bursts: various…