Search Publications
On the X-ray, optical emission line and black hole mass properties of local Seyfert galaxies
Cappi, M.; Iwasawa, K.; Barcons, X. +5 more
We investigate the relation between X-ray nuclear emission, optical emission line luminosities and black hole masses for a sample of 47 Seyfert galaxies. The sample, which has been selected from the Palomar optical spectroscopic survey of nearby galaxies (Ho et al. 1997a, ApJS, 112, 315), covers a wide range of nuclear powers, from L2-10 keV<…
The soft X-ray/NLR connection: a single photoionized medium?
Bianchi, S.; Guainazzi, M.; Chiaberge, M.
We present a sample of 8 nearby Seyfert 2 galaxies observed by HST and Chandra. All of the sources present soft X-ray emission which is coincident in extension and overall morphology with the [O iii] emission. The spectral analysis reveals that the soft X-ray emission of all the objects is likely to be dominated by a photoionized gas. This is stro…
X-ray spectral survey with XMM-Newton of a complete sample of nearby Seyfert galaxies
Cappi, M.; Filippenko, A. V.; Piconcelli, E. +15 more
Results obtained from an X-ray spectral survey of nearby Seyfert galaxies using XMM-Newton are reported. The sample was optically selected, well defined, complete in B magnitude, and distance limited: it consists of the nearest (D ⪉22 Mpc) 27 Seyfert galaxies (9 of type 1, 18 of type 2) taken from the Ho et al. (1997a, ApJS, 112, 315) sample. This…
XMM-Newton and INTEGRAL observations of new absorbed supergiant high-mass X-ray binaries
Parmar, A. N.; Walter, R.; Ubertini, P. +7 more
Context: .During the first year in operation, INTEGRAL, the European Space Agency's γ-ray observatory, has detected more than 28 new bright sources in the galactic plane which emit the bulk of their emission above 10 keV.
Aims: .To understand the nature of those sources we have obtained follow-up observations in the X-ray band with XMM-Newton.…
Spectral changes during dipping in low-mass X-ray binaries due to highly-ionized absorbers
Kaastra, J. S.; Díaz Trigo, M.; Parmar, A. N. +2 more
X-ray observations have revealed that many microquasars and low-mass X-ray binaries (LMXBs) exhibit narrow absorption features identified with resonant absorption from Fe XXV and Fe XXVI and other abundant ions. In many well studied systems there is evidence for blue-shifts, indicating outflowing plasmas. We succesfully model the changes in both t…
The multi-phase gaseous halos of star forming late-type galaxies. I. XMM-Newton observations of the hot ionized medium
Pietsch, W.; Dettmar, R. -J.; Rossa, J. +2 more
This study presents first results from an X-ray mini-survey carried out with XMM-Newton to investigate the diffuse Hot Ionized Medium in the halos of nine nearby star-forming edge-on spiral galaxies. Diffuse gaseous X-ray halos are detected in eight of our targets, covering a wide range of star formation rates from quiescent to starburst cases. Fo…
The XMM-Newton/Chandra monitoring campaign of the Galactic center region. Description of the program and preliminary results
Wijnands, R.; Homan, J.; van der Klis, M. +10 more
We present the first results of our X-ray monitoring campaign on a 1.7 square degree region centered on Sgr A* using the satellites XMM-Newton and Chandra. The purpose of this campaign is to monitor the behavior (below 10 keV) of X-ray sources (both persistent and transient) which are too faint to be detected by monitoring instruments aboard other…
XMM-Newton and Chandra measurements of the AGN intrinsic absorption: dependence on luminosity and redshift
Georgakakis, A.; Hatziminaoglou, E.; Georgantopoulos, I. +2 more
We combine bright XMM-Newton data with the Chandra Deep Field South observations to explore the behavior of the intrinsic AGN absorption, as a function of redshift and luminosity. Our sample consists of 359 sources selected in the hard 2-8 keV band, spanning the flux range 6 × 10-16-3 × 10-13 erg~cm-2~s-1
Charge-transfer induced EUV and soft X-ray emissions in the heliosphere
Lallement, R.; Izmodenov, V.; Quémerais, E. +4 more
Aims.We study the EUV/soft X-ray emission generated by charge transfer between solar wind heavy ions and interstellar neutral atoms and variations of the X-ray intensities and spectra with the line of sight direction, the observer location, the solar cycle phase and the solar wind anisotropies, and a temporary enhancement of the solar wind similar…
Structure and scaling of the entropy in nearby galaxy clusters
Arnaud, M.; Pointecouteau, E.; Pratt, G. W.
Using XMM-Newton observations, we investigate the scaling and structural properties of the ICM entropy in a sample of 10 nearby (z < 0.2) morphologically relaxed galaxy clusters in the temperature range 2-9 keV. We derive the local entropy-temperature (S{-}T) relation at R = 0.1, 0.2, 0.3 and 0.5R200. The logarithmic slope of the rel…