High Energy Astrophysics at Southampton
Lead Research Organisation:
University of Southampton
Department Name: Sch of Physics and Astronomy
Abstract
On the smallest scales we are interested in why pulsars seem to favour the low neutral hydrogen environments in the SMC. We are also interested in the products of stellar collisions and near misses in the high density environment of globular clusters, and in studying the compact objects (ie black holes, neutron stars, or white dwarfs) in our Galaxy which are strong emitter of optical light from hydgrogen atoms. Some galactic X-ray binary sources, which consist of black hole of similar mass to our sun together with a more normal star have, as well as accretion discs, through which matter spirals onto the black hole, strong jets. We want to understand the relationship between the emission from jets and from the hot X-ray emitting coronae and to find out how the jet might emerge from the corona. In some cases the disappearance of the inner disc is followed by ejection of material along the jet and we shall determine whether such behaviour is typical in Active Galaxies, ie galaxies whose emission is powered material falling onto (ie being accreted) by a massive black hole. In the 20-100 keV band where absorption of photons by cold gas is unimportant, and so we obtain a very clear view, we are surveying the Galactic Plane with INTEGRAL to determine an unbiased census of compact objects. As time goes on, we will extend that survey to the extragalactic sky. We study the X-ray variability of Active Galaxies to determine how they relate to galactic X-ray binaries sources and whether characteristic timescales reflect only mass or another parameter such as accretion rate. We are interested in the binary populations of nearby galaxies and in the so-called `ultra luminous X-ray sources (ULXs)'. ULXs may be the long sought after black holes with masses intermediate between those of galactic binaries and Active Galaxies and so are very important for testing mass-based scaling relationships. We are interested in how the emission in different wavebands (Gamma-ray, X-ray, optical/IR, radio) in binaries and Active Galaxies is related and what is the dependence on mass. We are interested how the jet emission from Active Galaxies heats clusters of galaxies. On the largest scales, we are interested in whether the different faint source populations which we see in the radio, X-ray and IR bands are just different manifestations of the same underlying phenomenon and how massive black hole growth might be related to growth of the galaxy in which the black hole lives. We are also building detailed theoretical models, using computers, to explain the complicated variability which we see in the sky at high energies.
Organisations
Publications
Gallo E
(2007)
The Spectral Energy Distribution of Quiescent Black Hole X-Ray Binaries: New Constraints from Spitzer
in The Astrophysical Journal
Migliari S
(2007)
Tracing the Jet Contribution to the Mid-IR over the 2005 Outburst of GRO J1655-40 via Broadband Spectral Modeling
in The Astrophysical Journal
Bassani L
(2007)
IGR J22517+2218=MG3 J225155+2217: A New Gamma-Ray Lighthouse in the Distant Universe
in The Astrophysical Journal
Sguera V
(2006)
Unveiling Supergiant Fast X-Ray Transient Sources with INTEGRAL
in The Astrophysical Journal
Evans D
(2008)
A Radio through X-Ray Study of the Jet/Companion-Galaxy Interaction in 3C 321
in The Astrophysical Journal
Wesson R
(2008)
A Planetary Nebula around Nova V458 Vulpeculae Undergoing Flash Ionization
in The Astrophysical Journal
Landi R
(2006)
Swift XRT Follow-up Observations of TeV Sources of the HESS Inner Galaxy Survey
in The Astrophysical Journal
Kraft R
(2008)
Evidence for Nonhydrostatic Gas Motions in the Hot Interstellar Medium of Centaurus A
in The Astrophysical Journal
Onken C
(2007)
The Black Hole Mass of NGC 4151: Comparison of Reverberation Mapping and Stellar Dynamical Measurements
in The Astrophysical Journal
Landi R
(2007)
The AGN Nature of 11 out of 12 Swift / RXTE Unidentified Sources through Optical and X-Ray Spectroscopy
in The Astrophysical Journal
Miller J
(2006)
A Long, Hard Look at the Low/Hard State in Accreting Black Holes
in The Astrophysical Journal
Caballero Garcia M
(2007)
The High-Energy Emission of GRO J1655-40 As Revealed with INTEGRAL Spectroscopy of the 2005 Outburst
in The Astrophysical Journal
Harris R
(2009)
GX 9+9: VARIABILITY OF THE X-RAY ORBITAL MODULATION
in The Astrophysical Journal
Capitanio F
(2009)
THE TWO INTEGRAL X-RAY TRANSIENTS IGR J17091-3624 AND IGR J17098-3628: A MULTIWAVELENGTH LONG-TERM CAMPAIGN
in The Astrophysical Journal
Croston J
(2008)
Chandra Evidence for AGN Feedback in the Spiral Galaxy NGC 6764
in The Astrophysical Journal
Bird J
(2008)
The Lifetime of FR II Sources in Groups and Clusters: Implications for Radio-Mode Feedback
in The Astrophysical Journal
Galache J
(2008)
A Long Look at the Be/X-Ray Binaries of the Small Magellanic Cloud
in The Astrophysical Journal Supplement Series
Casares J
(2009)
REFINED ORBITAL SOLUTION AND QUIESCENT VARIABILITY IN THE BLACK HOLE TRANSIENT GS 1354-64 (= BW Cir)
in The Astrophysical Journal Supplement Series
Bird A
(2007)
The Third IBIS/ISGRI Soft Gamma-Ray Survey Catalog
in The Astrophysical Journal Supplement Series