Skip to main content
Home
Department Of Physics text logo
  • Research
    • Our research
    • Our research groups
    • Our research in action
    • Research funding support
    • Summer internships for undergraduates
  • Study
    • Undergraduates
    • Postgraduates
  • Engage
    • For alumni
    • For business
    • For schools
    • For the public
Menu
Black Hole

Lensing of space time around a black hole. At Oxford we study black holes observationally and theoretically on all size and time scales - it is some of our core work.

Credit: ALAIN RIAZUELO, IAP/UPMC/CNRS. CLICK HERE TO VIEW MORE IMAGES.

Professor Roger Davies

Emeritus Wetton Professor

Research theme

  • Astronomy and astrophysics
  • Instrumentation

Sub department

  • Astrophysics

Research groups

  • Astronomical instrumentation
  • Cosmology
  • Galaxy formation and evolution
  • Hintze Centre for Astrophysical Surveys
  • Rubin-LSST
  • Extremely Large Telescope
Roger.Davies@physics.ox.ac.uk
  • About
  • Publications

Transient low-mass X-ray binary populations in elliptical galaxies NGC3379 and NGC4278

Astrophysical Journal 702:2 PART 2 (2009)

Authors:

T Fragos, V Kalogera, B Willems, K Belczynski, G Fabbiano, NJ Brassington, DW Kim, L Angelini, RL Davies, JS Gallagher, AR King, S Pellegrini, G Trinchieri, SE Zepf, A Zezas

Abstract:

We propose a physically motivated and self-consistent prescription for the modeling of transient neutron star low-mass X-ray binary (LMXB) properties, such as duty cycle (DC), outburst duration, and recurrence time. We apply this prescription to the population synthesis models of field LMXBs presented by Fragos etal., and compare the transient LMXB population to the Chandra X-ray survey of the two elliptical galaxies NGC3379 and NGC4278, which revealed several transient sources. We are able to exclude models with a constant DC for all transient systems, while models with a variable DC based on the properties of each system are consistent with the observed transient populations. We predict that the majority of the observed transient sources in these two galaxies are LMXBs with red giant donors. Finally, our comparison suggests that transient LMXBs are very rare in globular clusters (GCs), and thus the number of identified transient LMXBs may be used as a tracer of the relative contribution of field and GC LMXB populations. © 2009. The American Astronomical Society.
More details from the publisher

DEEP CHANDRA MONITORING OBSERVATIONS OF NGC 4278: CATALOG OF SOURCE PROPERTIES

ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES 181:2 (2009) 605-626

Authors:

NJ Brassington, G Fabbiano, D-W Kim, A Zezas, S Zepf, A Kundu, L Angelini, RL Davies, J Gallagher, V Kalogera, T Fragos, AR King, S Pellegrini, G Trinchieri
More details from the publisher

Galactic Bulges: the SAURON Perspective

GALAXY EVOLUTION: EMERGING INSIGHTS AND FUTURE CHALLENGES 419 (2009) 131-+

Authors:

Jesus Falcon-Barroso, Reynier F Peletier, Roland Bacon, Michele Cappellari, Roger L Davies, P Tim de Zeeuw, Eric Emsellem, Davor Krajnovic, Harald Kuntschner, Richard M McDermid, Marc Sarzi, Remco CE van den Bosch, Glenn van de Ven
More details

TRANSIENT LOW-MASS X-RAY BINARY POPULATIONS IN ELLIPTICAL GALAXIES NGC 3379 AND NGC 4278

ASTROPHYSICAL JOURNAL LETTERS 702:2 (2009) L143-L147

Authors:

T Fragos, V Kalogera, B Willems, K Belczynski, G Fabbiano, NJ Brassington, D-W Kim, L Angelini, RL Davies, JS Gallagher, AR King, S Pellegrini, G Trinchieri, SE Zepf, A Zezas
More details from the publisher

Discovery of hot gas in outflow in NGC 3379

Astrophysical Journal 688:2 (2008) 1000-1008

Authors:

G Trinchieri, S Pellegrini, G Fabbiano, R Fu, NJ Brassington, A Zezas, DW Kim, J Gallagher, L Angelini, RL Davies, V Kalogera, AR King, S Zepf

Abstract:

We report the discovery of a faint (Lx ∼ 4 ± 1.5 × 1037 ergs s-1, 0.5-2 keV), outflowing gaseous hot interstellar medium (ISM) in NGC 3379. This represents the lowest X-ray luminosity ever measured from a hot phase of the ISM in a nearby early-type galaxy. The discovery of the hot ISM in a very deep Chandra observation was possible thanks to its unique spectral and spatial signatures, which distinguish it from the integrated stellar X-ray emission, responsible for most of the unresolved emission in the Chandra data. This hot component is found in a region of ∼800 pc in radius at the center of the galaxy and has a total mass M ∼ 3 ± 1 × 105 M⊙. Independent theoretical prediction of the characteristics of an ISM in this galaxy, based on the intrinsic properties of NGC 3379, reproduce well the observed luminosity, temperature, and radial distribution and mass of the hot gas, and indicate that the gas is in an outflowing phase, predicted by models but not observed in any system so far.
More details from the publisher
More details

Pagination

  • First page First
  • Previous page Prev
  • …
  • Page 33
  • Page 34
  • Page 35
  • Page 36
  • Current page 37
  • Page 38
  • Page 39
  • Page 40
  • Page 41
  • …
  • Next page Next
  • Last page Last

Footer Menu

  • Contact us
  • Giving to the Dept of Physics
  • Work with us
  • Media

User account menu

  • Log in

Follow us

FIND US

Clarendon Laboratory,

Parks Road,

Oxford,

OX1 3PU

CONTACT US

Tel: +44(0)1865272200

University of Oxfrod logo Department Of Physics text logo
IOP Juno Champion logo Athena Swan Silver Award logo

© University of Oxford - Department of Physics

Cookies | Privacy policy | Accessibility statement

Built by: Versantus

  • Home
  • Research
  • Study
  • Engage
  • Our people
  • News & Comment
  • Events
  • Our facilities & services
  • About us
  • Current students
  • Staff intranet