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The X-ray and ultraviolet absorbing outflow in 3C 351

Mathur, Smita; Wilkes, Belinda Jane; Elvis, Martin S.; Fiore, Fabrizio (IOP Publishing, 1994)

3C 351 (z = 0.371), and X-ray-'quiet' quasar, is one of the few quasars showing signs of a 'warm absorber' in its X-ray spectrum; i.e., partially ionized absorbing material in the line of sight whose opacity depends on its ...

Absorption in X-ray spectra of high-redshift quasars

Elvis, Martin S.; Fiore, Fabrizio; Wilkes, Belinda Jane; McDowell, Jonathan Christopher; Bechtold, Jill (IOP Publishing, 1994)

We present evidence that X-ray absorption is common in high-redshift quasars. We have studied six high-redshift (z approximately 3) quasars with the ROSAT Position Sensitive Proportional Counter (PSPC) of which four are ...

The complex optical to soft x-ray spectrum of the low-redshift radio-quiet quasars

Fiore, Fabrizio; Elvis, Martin S.; McDowell, Jonathan Christopher; Siemiginowska, Aneta L.; Wilkes, Belinda Jane (IOP Publishing, 1994)

Eight high signal-to-noise ROSAT Position Sensitive Proportional Counter (PSPC) observations of six low-redshift (o.048 less than z less than 0.155) radio-quiet quasars have been analyzed to study ant soft excess. All the ...

PKS 0483-436 - A high-redshift quasar with strong X-ray absorption

Wilkes, Belinda Jane; Elvis, Martin S.; Fiore, Fabrizio; McDowell, Jonathan Christopher; Tananbaum, Harvey D.; Lawrence, Andrew (IOP Publishing, 1992)

The first X-ray spectrum of a high-redshift (z = 2.85) quasar is reported. The Rosat PSPC spectrum of PKS 0438-436, covering 0.3-9 keV in the quasar's rest frame, reveals unexpected absorption of about 1 x 10 exp 22/sq cm, ...

The ROSAT spectrum of 3C 351 - A warm absorber in an X-ray-'quiet' quasar?

Fiore, Fabrizio; Elvis, Martin S.; Mathur, Smita; Wilkes, Belinda Jane; McDowell, Jonathan Christopher (IOP Publishing, 1993)

3C 351 is one of the most X-ray-quiet radio quasars (alpha(ox) about 1.6). We have observed 3C 351 with the ROSAT position sensitive proportional counter (PSPC) and find a complex X-ray spectrum which is not well reproduced ...

X-ray absorption toward the red quasar 3C 212

Elvis, Martin S.; Fiore, Fabrizio; Mathur, Smita; Wilkes, Belinda Jane (IOP Publishing, 1994)

A Roentgen Satellite (ROSAT) X-ray spectrum of the z = 1.049 'red quasar' 3C 212 has a strong low-energy cutoff. The spectrum can be fitted with a power law (of energy index 1.4(+0.8, -0.6) with low-energy photoelectric ...

Multifrequency observations of KAZ 102 during the ROSAT all-sky survey

Treves, A.; Fink, H. H.; Malkan, M.; Wagner, S. J.; Wilkes, Belinda Jane; Baganoff, F.; Heidt, J.; Pian, E.; Sadun, A.; Schaeidt, S.; Bonnell, J. T.; Brinkmann, W.; de Martino, D.; Maraschi, L.; Tanzi, E. G.; Ulrich, M. H.; Wamsteker, W. (IOP Publishing, 1995)

The bright quasar Kaz 102, which lies in the vicinity of the North Ecliptic Pole, was monitored during the ROSAT All Sky Survey for 121.5 days from 1990 July 30 to 1991 January 25. In the course of the survey, optical ...

The soft x-ray properties of a complete sample of optically selected quasars. 1: First results

Laor, Ari; Fiore, Fabrizio; Elvis, Martin S.; Wilkes, Belinda Jane; McDowell, Jonathan Christopher (IOP Publishing, 1994)

We present the results of ROSAT position sensitive proportional counter (PSPC) observations of 10 quasars. These objects are part of our ROSAT program to observe a complete sample of optically selected quasars. This sample ...