Browsing by Author "Kriss, Gerard A."

Now showing items 1-3 of 3

    • Discovery of an Ultraviolet Counterpart to an Ultra-Fast X-ray Outflow in the Quasar PG1211+143 

      Kriss, Gerard A.; Lee, Julia C.; Danehkar, Ashkbiz; Nowak, Michael A.; Fang, Taotao; Hardcastle, Martin J.; Neilsen, Joseph; Young, Andrew (2018-02-02)
      We observed the quasar PG 1211+143 using the Cosmic Origins Spectrograph on the Hubble Space Telescope in 2015 April as part of a joint campaign with the Chandra X-ray Observatory and the Jansky Very Large Array. Our ...

    • Transient obscuration event captured in NGC~3227 II. Warm absorbers and obscuration events in archival XMM-Newton and NuSTAR observations 

      Wang, Yijun; Kaastra, Jelle; Mehdipour, Missagh; Mao, Junjie; Costantini, Elisa; Kriss, Gerard A.; Pinto, Ciro; Ponti, Gabriele; Behar, Ehud; Bianchi, Stefano; Branduardi-Raymont, Graziella; Marco, Barbara De; Grafton-Waters, Sam; Petrucci, Pierre-Olivier; Ebrero, Jacobo; Walton, Dominic James; Kaspi, Shai; Xue, Yongquan; Paltani, Stéphane; Gesu, Laura di; He, Zhicheng (2022-01-14)
      The relationship between warm absorber (WA) outflows of active galactic nuclei and nuclear obscuration activities caused by optically thick clouds (obscurers) crossing the line of sight is still unclear. NGC 3227 is a ...

    • The Ultra-Fast Outflow of the Quasar PG 1211+143 as Viewed by Time-Averaged Chandra Grating Spectroscopy 

      Danehkar, Ashkbiz; Nowak, Michael A.; Lee, Julia C.; Kriss, Gerard A.; Young, Andrew J.; Hardcastle, Martin J.; Chakravorty, Susmita; Fang, Taotao; Neilsen, Joseph; Rahoui, Farid; Smith, Randall K. (2018-02-02)
      We present a detailed X-ray spectral study of the quasar PG 1211+143 based on Chandra High Energy Transmission Grating Spectrometer (HETGS) observations collected in a multi-wavelength campaign with UV data using the Hubble ...