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On the link between rotation, chromospheric activity and Li abundance in subgiant stars
De Medeiros, J. R.; Canto Martins, B. L.; Melo, C. H. F. +2 more
The connection rotation-CaII emission flux-lithium abundance is analyzed for a sample of bona fide subgiant stars, with evolutionary status determined from HIPPARCOS trigonometric parallax measurements and from the Toulouse-Geneva code. The distribution of rotation and CaII emission flux as a function of effective temperature shows a discontinuity…
INTEGRAL observations of the black hole candidate H 1743-322 in outburst
Parmar, A. N.; Kuulkers, E.; Oosterbroek, T. +5 more
INTEGRAL made 3 observations in 2003 April of the black hole candidate H 1743-322 during the rising part, and close to the maximum, of an outburst. H 1743-322 was previously observed in outburst in 1977-1978. The source is located in a crowded region of the sky (l = 357o, b = -2o) and at least 18 sources are clearly detected …
The X-ray spectra of the flaring and quiescent states of AT Microscopii observed by XMM-Newton
Raassen, A. J. J.; Mewe, R.; Audard, M. +1 more
The X-ray spectrum of the late-type M-dwarf binary AT Mic (dM4.5e+dM4.5e) is observed in the wavelength range 1-40 Å by means of RGS and EPIC-MOS on board XMM-Newton. During the exposure a flare occured. We have performed a 3-temperature fit and a DEM-modeling to the flaring and quiescent part of the spectrum. We report the coronal temperature dis…
Variation of coronal line widths on and off the disk
Poedts, S.; Banerjee, D.; O'Shea, E.
We present observations of a Mg X 625 Å coronal line, obtained with the CDS instrument on SoHO, extending from the disk part of the coronal hole to ~ 90 000 km above the limb in the north polar coronal hole. Observations were performed in polar plumes and inter-plume lanes. To obtain a sufficiently high signal-to-noise ratio the observations were …
XMM-Newton study of hard X-ray sources in IC 443
Bocchino, F.; Bykov, A. M.
We present XMM-Newton observations of hard X-ray emission from the field of IC 443, a supernova remnant interacting with a molecular cloud. The hard emission from the field is dominated by 12 isolated sources having 2-10 keV flux {ga } 10-14 erg cm-2 s-1. Only a fraction of the sources are expected to be extragalac…
Gas-phase CO2, C2H2, and HCN toward Orion-KL
van Dishoeck, E. F.; Wright, C. M.; Lahuis, F. +3 more
The infrared spectra toward Orion-IRc2, Peak 1 and Peak 2 in the 13.5-15.5 mu m wavelength range are presented, obtained with the Short Wavelength Spectrometer on board the Infrared Space Observatory. The spectra show absorption and emission features of the vibration-rotation bands of gas-phase CO2, HCN, and C2H2, …
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…
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 …
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