activity
19972002
collaborators

8 papers

astro-ph2002

New Chandra/HST-STIS results on Seyfert I AGN: Photoionized Outflows

B. McKernan, T. Yaqoob

We present soft X-ray results from observations with the Chandra HETGS of the Seyfert I AGN NGC 4593 and Mrk 509. We discuss the photoionized outflows associated with Seyfert I AGN…

astro-ph2002

Chandra Grating Observations of AGN

T. Yaqoob, U. Padmanabhan

The highest spectral resolution data for the Fe-K lines in type I AGN, as observed with the Chandra High Energy Grating (HEG), reveal a variety of line shapes. However, the energie…

astro-ph2001

Chandra Grating Observations of Seyfert 1 Galaxies

T. Yaqoob, I. M. George, T. J. Turner

We present new results from a Chandra HETG observation of NGC 5548 and give a comparison of absorption and emission features found in other Seyfert 1 galaxies using Chandra grating…

astro-ph2001

Subtleties in Measuring Iron K Lines in AGN

T. Yaqoob, U. Padmanabhan, T. Dotani +3

Chandra and XMM observations are showing that the Fe-K emission lines in type 1 AGN are composite, in general consisting of a narrow and a broad component. We review the latest Cha…

astro-ph2000

What Kind of Obscured AGN Make the Cosmic X-ray Background?

T. Yaqoob

While it is understood that the origin of the Cosmic X-ray Background (CXRB) can be explained in terms of a combination of obscured and unobscured AGN, the identity of these obscur…

astro-ph1999

Short-timescale Variability in the Broadband Emission of the Blazars Mkn421 and Mkn501

M. J. Carson, B. McKernan, T. Yaqoob +1

We analyse ASCA x-ray data and Whipple γ-ray data from the blazars Mkn421 and Mkn501 for short-timescale variability. We find no evidence for statistically significant (>3σ) variab…