Now showing items 1-20 of 42

    • A 78 Day X-Ray Period Detected from NGC 5907 ULX1 by $\textit{Swift}$ 

      Walton, Dominic James; Fürst, F; Bachetti, M; Barret, D; Brightman, M; Fabian, Andrew Christopher; Gehrels, N et al. (IOP Publishing, 2016-08-10)
      We report the detection of a 78.1 ± 0.5 day period in the X-ray light curve of the extreme ultraluminous X-ray source NGC 5907 ULX1 (L$_\text{X,peak}$ ~ 5 × 10$^{40}$ erg s$^{-1}$), discovered during an extensive monitoring ...
    • AGN-starburst evolutionary connection: a physical interpretation based on radiative feedback 

      Ishibashi, W; Fabian, Andrew Christopher (Oxford University Press, 2016-12-01)
      Observations point towards a close connection between nuclear starbursts, active galactic nuclei (AGN), and outflow phenomena. An evolutionary sequence, starting from a dust-obscured ultra-luminous infrared galaxy and ...
    • Alma Observations of Massive Molecular Gas Filaments Encasing Radio Bubbles in the Phoenix Cluster 

      Russell, Helen Rebecca; McDonald, M; McNamara, BR; Fabian, Andrew Christopher; Nulsen, PEJ; Bayliss, MB; Benson, BA et al. (Institute of Physics, 2017-02-14)
      We report new ALMA observations of the CO(3-2) line emission from the 2.1 $\pm$ 0.3 x 10$^{10}$ $\textit{M}$$\odot$ molecular gas reservoir in the central galaxy of the Phoenix cluster. The cold molecular gas is fueling a ...
    • Athena Wide Field Imager Key Science Drivers 

      Rau, A; Nandra, K; Aird, James Alexander; Comastri, A; Dauser, T; Merloni, A; Pratt, GW et al. (SPIE, 2016-07-11)
      The Wide Field Imager (WFI) is one of two instruments for the Advanced Telescope for High-ENergy Astrophysics (Athena). In this paper we summarise three of the many key science objectives for the WFI – the formation and ...
    • Broadband Observations of High Redshift Blazars 

      Paliya, VS; Parker, Michael; Fabian, Andrew Christopher; Stalin, CS (IOP, 2016-07-01)
      We present a multi-wavelength study of four high redshift blazars, S5 0014+81 (z = 3.37), CGRaBS J0225+1846 (z = 2.69), BZQ J1430+4205 (z = 4.72), and 3FGL J1656.2−3303 (z = 2.40) using quasi-simultaneous data from the ...
    • The Broadband Spectral Variability of Holmberg IX X-1 

      Walton, Dominic James; Furst, F; Harrison, FA; Middleton, MJ; Fabian, Andrew Christopher; Bachetti, M; Barret, D et al. (Institute of Physics, 2017-04-21)
      We present results from four new broadband X-ray observations of the extreme ultraluminous X-ray source Holmberg IX X-1 (L$_{x}$ > 10$^{40}$ erg s$^{-1}$), performed by $\textit{Suzaku}$ and $\textit{Nu}$STAR in coordination. ...
    • Constraining the mass of accreting black holes in ultraluminous X-ray sources with ultrafast outflows 

      Fiacconi, Davide; Pinto, Ciro; Walton, Dominic James; Fabian, Andrew Christopher (Oxford University Press, 2017-07-21)
      The nature of ultraluminous X-ray sources (ULXs) – off-nuclear extragalactic sources with luminosity, assumed isotropic, ≳1039 erg s−1 – is still debated. One possibility is that ULXs are stellar black holes (BHs) accreting ...
    • Detecting edges in the X-ray surface brightness of galaxy clusters 

      Sanders, JS; Fabian, Andrew Christopher; Russell, Helen Rebecca; Walker, Stephen Alexander; Blundell, KM (Oxford University Press, 2016-08-01)
      The effects of many physical processes in the intracluster medium of galaxy clusters imprint themselves in X-ray surface brightness images. It is therefore important to choose optimal methods for extracting information ...
    • The detection and X-ray view of the changing look AGN HE 1136-2304 

      Parker, Michael; Komossa, S; Kollatschny, W; Walton, Dominic James; Schartel, N; Santos-Lleó, M; Harrison, FA et al. (Oxford University Press, 2016-09-11)
      We report the detection of high-amplitude X-ray flaring of the AGN HE 1136-2304, which is accompanied by a strong increase in the flux of the broad Balmer lines, changing its Seyfert type from almost type 2 in 1993 down ...
    • Disc reflection and a possible disc wind during a soft X-ray state in the neutron star low-mass X-ray binary 1RXS J180408.9-342058 

      Degenaar, Nathalie Deborah; Altamirano, D; Parker, Michael Andrew; Miller-Jones, JCA; Miller, JM; Heinke, CO; Wijnands, R et al. (Oxford University Press, 2016-10-01)
      1RXS J180408.9–342058 is a transient neutron star low-mass X-ray binary that exhibited a bright accretion outburst in 2015. We present $\textit{NuSTAR}$, $\textit{Swift}$, and $\textit{Chandra}$ observations obtained around ...
    • Discovery of coherent pulsations from the Ultraluminous X-ray Source NGC 7793 P13 

      Fuerst, F; Walton, Dominic James; Harrison, FA; Stern, D; Barret, D; Brightman, M; Fabian, Andrew Christopher et al. (Institute of Physics Publishing, 2016-11-10)
      We report the detection of coherent pulsations from the ultraluminous X-ray source (ULX) NGC 7793 P13. The ≈0.42 s nearly sinusoidal pulsations were initially discovered in broadband X-ray observations using XMM-Newton and ...
    • DISK–WIND CONNECTION DURING THE HEARTBEATS OF GRS 1915+105 

      Zoghbi, A; Miller, JM; King, AL; Miller, MC; Proga, D; Kallman, T; Fabian, Andrew Christopher et al. (IOP Publishing, 2016-12-20)
      Disk and wind signatures are seen in the soft state of Galactic black holes, while the jet is seen in the hard state. Here we study the disk–wind connection in the ρ class of variability in GRS 1915+105 using a joint ...
    • The distribution of dark and luminous matter in the unique galaxy cluster merger Abell 2146 

      King, LJ; Clowe, DI; Coleman, JE; Russell, Helen Rebecca; Santana, R; White, JA; Canning, REA et al. (Oxford University Press, 2016-06-11)
      Abell 2146 ($z$ = 0.232) consists of two galaxy clusters undergoing a major merger. The system was discovered in previous work, where two large shock fronts were detected using the $\textit{Chandra X-ray Observatory}$, ...
    • Do high redshift quasars have powerful jets? 

      Fabian, Andrew Christopher; Walker, Stephen Alexander; Celotti, A; Ghisellini, G; Mocz, P; Blundell, KM; McMahon, Richard Gerard (2014-06-04)
    • Do sound waves transport the AGN energy in the Perseus cluster? 

      Fabian, Andrew Christopher; Walker, Stephen Alexander; Russell, Helen Rebecca; Pinto, Ciro; Sanders, JS; Reynolds, CS (Oxford University Press, 2017-01-01)
      The level of random motions in the intracluster gas lying between 20 and 60 kpc radius in the core of the Perseus cluster has been measured by the Hitomi Soft X-ray Spectrometer (SXS) at 164 ± 10 km s$^{−1}$ . The maximum ...
    • The effects of high density on the X-ray spectrum reflected from accretion discs around black holes 

      Garcia, JA; Fabian, Andrew Christopher; Kallman, TR; Dauser, T; Parker, ML; McClintock, JE; Steiner, JF et al. (Oxford University Press, 2016-10-11)
      Current models of the spectrum of X-rays reflected from accretion discs around black holes and other compact objects are commonly calculated assuming that the density of the disc atmosphere is constant within several Thomson ...
    • From ultraluminous X-ray sources to ultraluminous supersoft sources: NGC 55 ULX, the missing link 

      Pinto, Ciro; Alston, W; Soria, R; Middleton, MJ; Walton, Dominic James; Sutton, AD; Fabian, Andrew Christopher et al. (Oxford University Press, 2017-07)
      In recent work with high-resolution reflection grating spectrometers (RGS) aboard $\textit{XMM–Newton}$, Pinto et al. have discovered that two bright and archetypal ultraluminous X-ray sources (ULXs) have strong relativistic ...
    • Future of X-ray reverberation from AGN 

      Fabian, Andrew Christopher; Alston, William Nicholas; Cackett, EM; Kara, E; Uttley, P; Wilkins, DR (Wiley, Wiley, 2017-03-01)
      XMM-Newton is capable of making a transformational advance in our understanding of how luminous accreting black holes work, by dedicating about 10% of future observing time to long observations, of order Megaseconds, to ...
    • The geometry of the infrared and x-ray obscurer in a dusty hyperluminous quasar 

      Farrah, D; Baloković, M; Stern, D; Harris, K; Kunimoto, M; Walton, Dominic James; Alexander, DM et al. (IOP Publishing, 2016-11-01)
      We study the geometry of the active galactic nucleus (AGN) obscurer in IRAS 09104+4109, an IR-luminous, radio-intermediate FR-I source at $z$ = 0.442, using infrared data from $\textit{Spitzer}$ and $\textit{Herschel}$, ...