High Energy Astrophysics at Southampton
Lead Research Organisation:
University of Southampton
Department Name: Sch of Physics and Astronomy
Abstract
On the stellar scale we are interested in the significance of different environments on the evolution of high mass X-ray binary (HMXB) populations, in particular between the Milky Way and the SMC, where differing star formation rates and metallicities could be crucial. What are the relative importances of local and interstellar obscuration in what we see? Here the upcoming 2Msec INTEGRAL Key Programme observation of the SMC, almost unaffected by obscuration, will be of great value. Globular clusters are outstanding laboratories for studying stellar dynamics and stellar evolution, especially for understanding the most exotic stellar populations. We are drawing together observations of large samples of globular clusters to understand which cluster properties are most important for the production of these exotic stars, and comparing with low stellar density dwarf spheroidal galaxies to isolate the stellar evolution from stellar dynamics. The Netherlands-based low frequency radio array, LOFAR, is about to open a new window on the universe providing the first radio `all sky monitor'. We will study coherent radio bursts, perhaps associated with merging neutron stars, detectable at enormous distances (to z=7), providing a unique probe of the intergalactic medium and possibly even testing theories of gravity and cosmological distance scales via identification of LIGO inspiral events We will continue our research into the coupling between accretion and outflow (jets) in X-ray binaries, and how it relates to parallel processes in AGN (where scaling laws with black hole mass are established), accreting neutron stars and white dwarfs. We have amassed the first comprehensive database of black hole spectral states and will extend this analysis to include X-ray timing and radio results. Thus we will produce the most comprehensive analysis to date of the relation between black hole accretion flows and the formation and power of relativistic jets. The results can be applied to AGN feedback in galaxies and clusters. We will greatly improve our knowledge of the scaling relationship between characteristic X-ray timescale, mass and accretion rate in Seyfert galaxies and Galactic binaries, thus testing physical models for this important universal relationship. We will determine whether the relationship applies in jet dominated ``blazars'', implying a universal origin for variability. We are building a model, based on propagating fluctuations, to provide physical understanding of all spectral-timing relationships to derive physical parameters, eg disc emissivity profile. This model, with additional X-ray reprocessing, should also explain X-ray/optical correlations in AGN so we will test it against our X-ray/optical monitoring. To provide a census of the nearby universe on which models of the more distant universe can be built, we are heavily involved in eMERLIN legacy surveys of nearby galaxy samples It is now widely accepted that some process must reheat the gas in galaxy clusters or large amounts of cool gas, which are not seen, would be found in the cores of clusters of galaxies. But what is the heating mechanism? In our most theoretical project we will investigate, via MHD simulations, whether the dissipation of turbulent energy, driven by merger events, galaxy motions and AGN outflows, may be responsible. On the largest scales, both AGN and starforming galaxies (SFGs) contribute to the faint radio source population, but what is the mix? By combining radio morphology with a variety of spectral energy diagnostics we can distinguish AGN from SFGs. Hence, using radio luminosity as a starformation rate (SFR) indicator, we can determine the evolution of the cosmic SFR in an absorption-independent manner. We will push this technique to much higher redshifts, as major contributors to eMERLIN deep field legacy surveys, and also probe the relationship between SFGs and AGN.
Organisations
Publications

Fender R
(2010)
No evidence for black hole spin powering of jets in X-ray binaries Black hole binary jets
in Monthly Notices of the Royal Astronomical Society

Uthas H
(2012)
Two new accreting, pulsating white dwarfs: SDSS J1457+51 and BW Sculptoris Two new pulsating CVs: J1457 and BW Scl
in Monthly Notices of the Royal Astronomical Society

Russell D
(2011)
A tool to separate optical/infrared disc and jet emission in X-ray transient outbursts: the colour-magnitude diagrams of XTE J1550-564 CMDs to separate OIR disc/jet emission
in Monthly Notices of the Royal Astronomical Society

Wang Y
(2009)
A relativistic mixing-layer model for jets in low-luminosity radio galaxies
in Monthly Notices of the Royal Astronomical Society

Davis P
(2012)
Is the common envelope ejection efficiency a function of the binary parameters? The common envelope ejection efficiency
in Monthly Notices of the Royal Astronomical Society

Calvelo D
(2010)
Limits on the quiescent radio emission from the black hole binaries GRO J1655-40 and XTE J1550-564 Quiescent limits of GRO J1655-40 and XTE J1550-564
in Monthly Notices of the Royal Astronomical Society

Arévalo P
(2009)
Correlation and time delays of the X-ray and optical emission of the Seyfert Galaxy NGC 3783
in Monthly Notices of the Royal Astronomical Society

Cabanac C
(2009)
On the variation of black hole accretion disc radii as a function of state and accretion rate
in Monthly Notices of the Royal Astronomical Society

Cornelisse R
(2012)
The nature of the X-ray transient MAXI J0556-332 MAXI J0556-332
in Monthly Notices of the Royal Astronomical Society

Calvelo D
(2012)
Radio observations of Circinus X-1 over a complete orbit at an historically faint epoch Observations of CIR X-1 over a complete orbit
in Monthly Notices of the Royal Astronomical Society

Moin A
(2011)
e-VLBI observations of Circinus X-1: monitoring of the quiescent and flaring radio emission on au scales e-VLBI observations of Circinus X-1
in Monthly Notices of the Royal Astronomical Society

Soleri P
(2010)
Investigating the disc-jet coupling in accreting compact objects using the black hole candidate Swift J1753.5-0127 Disc-jet coupling in black hole candidates
in Monthly Notices of the Royal Astronomical Society

Scaringi S
(2009)
Classifying broad absorption line quasars: metrics, issues and a new catalogue constructed from SDSS DR5
in Monthly Notices of the Royal Astronomical Society

Jamil O
(2010)
iShocks: X-ray binary jets with an internal shocks model
in Monthly Notices of the Royal Astronomical Society

Soleri P
(2011)
On the nature of the 'radio-quiet' black hole binaries Radio-quiet black hole binaries
in Monthly Notices of the Royal Astronomical Society

Cottis C
(2010)
Searching for the signature of radiative line driving: on the absence of Lya-N v line-locking features in a large sample of BALQSOs Radiative line driving in BALQSOs
in Monthly Notices of the Royal Astronomical Society

Emmanoulopoulos D
(2014)
General relativistic modelling of the negative reverberation X-ray time delays in AGN?
in Monthly Notices of the Royal Astronomical Society

Symeonidis M
(2009)
The link between SCUBA and Spitzer : cold galaxies at z ? 1
in Monthly Notices of the Royal Astronomical Society

Bell M
(2011)
X-ray and radio variability in the low-luminosity active galactic nucleus NGC 7213 NGC 7213: X-ray and radio variability
in Monthly Notices of the Royal Astronomical Society

Pretorius M
(2012)
The space density and X-ray luminosity function of non-magnetic cataclysmic variables Space density and luminosity function of CVs
in Monthly Notices of the Royal Astronomical Society

Leigh N
(2011)
An analytic model for blue straggler formation in globular clusters Blue straggler formation in globular clusters
in Monthly Notices of the Royal Astronomical Society

Shahbaz T
(2010)
Observations of the quiescent X-ray transients GRS 1124-684 (=GU Mus) and Cen X-4 (=V822 Cen) taken with ULTRACAM on the VLT
in Monthly Notices of the Royal Astronomical Society

Jurua E
(2011)
The optical and X-ray light curves of Hercules X-1 The optical and X-ray light curves of Her X-1
in Monthly Notices of the Royal Astronomical Society

Groot P
(2009)
The UV-Excess survey of the northern Galactic plane
in Monthly Notices of the Royal Astronomical Society

Kotze M
(2009)
Discovery of long-term superorbital periodicities in the pseudo-transient LMXBs: IGR J17098-3628 and EXO 0748-676
in Monthly Notices of the Royal Astronomical Society
Description | Many details regarding the accretion of material onto compact objects such as black holes, and the resulting emission, particularly with regard to the variability properties and to jets |
Exploitation Route | We work on some of the major questions in high energy astrophysics and our work on timing properties and scaling relationships between different mass and accretion rates will certainly form the basis of future examinations of scaling relationships, ie are black holes the same, apart from scale? |
Sectors | Creative Economy Education |
Description | Other researchers have applied the techniques developed during the course of this grant to different types of astrophysical objects. We have also used them in the context of undergraduate projects on the time series analysis of stock market data, resulting the in the said undergraduates getting better paid jobs than their lecturers. |
First Year Of Impact | 2010 |
Sector | Creative Economy,Education,Financial Services, and Management Consultancy |
Impact Types | Cultural |