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.

Angela Taylor

Professor of Experimental Astrophysics

Research theme

  • Astronomy and astrophysics
  • Particle astrophysics & cosmology
  • Instrumentation

Sub department

  • Astrophysics

Research groups

  • Experimental radio cosmology
  • C-BASS
  • The Square Kilometre Array (SKA)
Angela.Taylor@physics.ox.ac.uk
Telephone: 01865 (2)73297
Denys Wilkinson Building, room 753
  • About
  • Publications

C-Band All-Sky Survey: a first look at the Galaxy

Monthly Notices of the Royal Astronomical Society Oxford University Press 448:4 (2015) 3572-3586

Authors:

MO Irfan, C Dickinson, RD Davies, C Copley, RJ Davis, Pedro Ferreira, CM Holler, JL Jonas, Michael Jones, OG King, JP Leahy, Jamie Leech, EM Leitch, SJC Muchovej, TJ Pearson, MW Peel, ACS Readhead, MA Stevenson, D Sutton, Angela Taylor, J Zuntz

Abstract:

We present an analysis of the diffuse emission at 5 GHz in the first quadrant of the Galactic plane using two months of preliminary intensity data taken with the C-Band All-Sky Survey (C-BASS) northern instrument at the Owens Valley Radio Observatory, California. Combining C-BASS maps with ancillary data tomake temperature-temperature plots, we find synchrotron spectral indices of β = -2.65 ± 0.05 between 0.408 and 5 GHz and β = -2.72 ± 0.09 between 1.420 and 5 GHz for -10° > |b| > -4°, 20° > l > 40°. Through the subtraction of a radio recombination line free-free template, we determine the synchrotron spectral index in the Galactic plane (|b|>4°) to be β =-2.56±0.07 between 0.408 and 5 GHz, with a contribution of 53±8 per cent from free-free emission at 5 GHz. These results are consistent with previous low-frequency measurements in the Galactic plane. By including C-BASS data in spectral fits, we demonstrate the presence of anomalous microwave emission (AME) associated with the HII complexes W43, W44 and W47 near 30 GHz, at 4.4Σ, 3.1Σ and 2.5Σ, respectively. The CORNISH (Co-Ordinated Radio 'N' Infrared Survey for High mass star formation) VLA 5-GHz source catalogue rules out the possibility that the excess emission detected around 30 GHz may be due to ultracompact HII regions. Diffuse AME was also identified at a 4Σ level within 30° > l > 40°, -2° > b > 2° between 5 and 22.8 GHz.

More details from the publisher
Details from ORA
More details
Details from ArXiV

Astronomical receiver modelling using scattering matrices

Monthly Notices of the Royal Astronomical Society Oxford University Press (OUP) 446:2 (2015) 1252-1267

Authors:

OG King, Michael E Jones, C Copley, RJ Davis, JP Leahy, J Leech, SJC Muchovej, TJ Pearson, Angela C Taylor
More details from the publisher
More details
Details from ArXiV

Astronomical receiver modelling using scattering matrices

Monthly Notices of the Royal Astronomical Society Oxford University Press (OUP) 446:2 (2015) 1252-1267

Authors:

OG King, ME Jones, C Copley, RJ Davis, JP Leahy, J Leech, SJC Muchovej, TJ Pearson, AC Taylor

The C-Band All-Sky Survey (C-BASS): design and implementation of the northern receiver

Monthly Notices of the Royal Astronomical Society Oxford University Press (OUP) 438:3 (2014) 2426-2439

Authors:

OG King, Michael E Jones, EJ Blackhurst, C Copley, RJ Davis, C Dickinson, CM Holler, MO Irfan, JJ John, JP Leahy, J Leech, SJC Muchovej, TJ Pearson, MA Stevenson, Angela C Taylor
More details from the publisher
More details
Details from ArXiV

A circularly symmetric antenna design with high polarization purity and low spillover

IEEE Transactions on Antennas and Propagation 61:1 (2013) 117-124

Authors:

CM Holler, AC Taylor, ME Jones, OG King, SJC Muchovej, MA Stevenson, RJ Wylde, CJ Copley, RJ Davis, TJ Pearson, ACS Readhead

Abstract:

We describe the development of two circularly symmetric antennas with high polarization purity and low spill-over. Both were designed to be used in an all-sky polarization and intensity survey at 5 GHz (the C-Band All-Sky Survey, C-BASS). The survey requirements call for very low cross-polar signal levels and far-out sidelobes. Two different existing antennas, with 6.1-m and 7.6-m diameter primaries, were adapted by replacing the feed and secondary optics, resulting in identical beam performances of 0.73\circ FWHM, cross-polarization better than - 50 dB, and far-out sidelobes below -70 dB. The polarization purity was realized by using a symmetric low-loss dielectric foam support structure for the secondary mirror, avoiding the need for secondary support struts. Ground spill-over was largely reduced by using absorbing baffles around the primary and secondary mirrors, and by the use of a low-sidelobe profiled corrugated feedhorn. The 6.1-m antenna and receiver have been completed and tested. Results show that the co-polar beam matches the design simulations very closely in the main beam and down to levels of - 80 dB in the backlobes. With the absorbing baffles in place the far-out (>100{\circ}) sidelobe response is reduced below -90 dB. Cross-polar response could only be measured down to a noise floor of - 20 dB but is also consistent with the design simulations. Temperature loading and groundspill due to the secondary support were measured at less than 1 K. © 1963-2012 IEEE.
Details from ArXiV
More details from the publisher
More details

Pagination

  • First page First
  • Previous page Prev
  • …
  • Page 3
  • Page 4
  • Page 5
  • Page 6
  • Current page 7
  • Page 8
  • Page 9
  • Page 10
  • Page 11
  • …
  • 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