Search Publications
XMM-Newton observations of ULIRGs: A Compton-thick AGN in IRAS 19254-7245
Cappi, M.; Franceschini, A.; Malaguti, G. +8 more
We present the XMM-Newton observation of the merging system IRAS 19254-7245, also known as The Superantennae, whose southern nucleus is classified as a Seyfert 2 galaxy. The XMM-Newton data have allowed us to perform a detailed X-ray imaging and spectral analysis of this system. We clearly detect, for the first time in this system, a strong (EW \s…
XMM-Newton observation of the galactic centre - evidence against the X-ray reflection nebulae model?
Costantini, E.; Hasinger, G.; Predehl, P. +1 more
We present preliminary results of a 50 ksec \XMM observation of the Galactic Centre. Due to the excellent spectral resolution of \XMM combined with its high throughput at energies even beyond 7 keV, the iron line complex could be resolved into individual components (neutral, ionized, both in Kalpha and Kbeta ) in the spectra of a number of sources…
Photometric mapping with ISOPHOT using the ``P32'' Astronomical Observation Template
Gabriel, C.; Tuffs, R. J.
The ``P32'' Astronomical Observation Template (AOT) provided a means to map large areas of sky (up to 45x 45 arcmin) in the far-infrared (FIR) at high redundancy and with sampling close to the Nyquist limit using the ISOPHOT C100 (3x 3) and C200 (2x 2) detector arrays on board the Infrared Space Observatory (ISO). However, the transient response b…
Optical identification of the companion to PSR J1911-5958A, the pulsar binary in the outskirts of NGC 6752
van Kerkwijk, M. H.; Verbunt, F.; Bassa, C. G. +1 more
We report on the identification of the optical counterpart of the binary millisecond pulsar PSR J1911-5958A, located in the outskirts of the globular cluster NGC 6752. At the position of the pulsar we find an object with V=22.08, B-V=0.38, U-B=-0.49. The object is blue with respect to the cluster main sequence by 0.8 mag in B-V. We argue that the …
The identification of HCN and HNC in carbon stars: model atmospheres, synthetic spectra and fits to observations in the 2.7-4.0 µm region
Jones, H. R. A.; Tennyson, J.; Pavlenko, Ya. V. +1 more
Model carbon star atmospheres and synthetic spectra have been calculated using the recent HCN/HNC vibration rotation line list of Harris et al. The calculations are repeated using only HCN lines and show that HNC has a significant effect upon the temperature, density and optical depth of a stellar atmosphere.
We fit synthetic spectra in the 2…
Hard X-ray timing and spectral properties of PSR B0540-69
de Plaa, J.; Kuiper, L.; Hermsen, W.
We report the hard X-ray properties of the young Crab-like LMC pulsar
Formation of Minor-Ion Charge States in the Fast Solar Wind: Roles of Differential Flow Speeds of Ions of the Same Element
Chen, Y.; Hu, Y.; Esser, R.
To investigate the possibility of differential flow speeds between ions of the same element and their roles in the determination of ionic fractions, this paper extends our latest minor-ion model to a five-fluid model, describing the behavior of five species of minor ions of one given element in the fast solar wind. We solve the five sets of mass, …
Orbit design for launching INTEGRAL on the Proton/Block-DM launcher
Clausen, K.; Eismont, N. A.; Janin, G. +6 more
This paper describes some aspects of the mission design determined by use of the Proton/Block-DM launch vehicle in the version used for injection onto a highly elliptical orbit of the international gamma-ray astrophysics laboratory INTEGRAL. Methods and results used for choosing an operational orbit for INTEGRAL are presented.
Using Multiwavelength Observations to Determine the Black Hole Mass and Accretion Rate in the Type 1 Seyfert Galaxy NGC 5548
Chiang, James; Blaes, Omer
We model the spectral energy distribution of the type 1 Seyfert galaxy NGC 5548, fitting data from simultaneous optical, UV, and X-ray monitoring observations. We assume a geometry consisting of a hot central Comptonizing region surrounded by a thin accretion disk. The properties of the disk and the hot central region are determined by the feedbac…
First INTEGRAL observations of GRS 1915+105
Belloni, T.; Charles, P. A.; Rodriguez, J. +20 more
We present data from the first of six monitoring Open Time observations of GRS 1915+105 undertaken with the orbiting INTEGRAL satellite. The source was clearly detected with all three X-ray and gamma-ray instruments on board. GRS 1915+105 was in a highly variable state, as demonstrated by the JEM X-2 and ISGRI lightcurves. These and simultaneous R…