EDP Sciences
Free access
Volume 384, Number 1, March II 2002
Page(s) 195 - 205
Section Formation, structure and evolution of stars
DOI http://dx.doi.org/10.1051/0004-6361:20011820

A&A 384, 195-205 (2002)
DOI: 10.1051/0004-6361:20011820

Pulsations and orbital modulation of the intermediate polar 1WGA J1958.2+3232

A. J. Norton1, H. Quaintrell1, S. Katajainen2, H. J. Lehto2, K. Mukai3 and I. Negueruela4

1  Department of Physics and Astronomy, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK
    e-mail: A.J.Norton@open.ac.uk; H.Quaintrell@open.ac.uk
2  Tuorla Observatory, Turku University, Väisäläntie 20, 21500 Piikkiö, Finland
    e-mail: sekataja@astro.utu.fi; hlehto@astro.utu.fi
3  NASA Goddard Space Flight Center, Laboratory for High Energy Astrophysics, Code 662, Greenbelt, MD 20771, USA and Universities Space Research Association
    e-mail: mukai@milkyway.gsfc.nasa.gov
4  Observatoire Astronomique de Strasbourg, 11 rue de l'Université, 67000 Strasbourg, France
    e-mail: ignacio@isaac.u-strasbg.fr

(Received 20 November 2001 / Accepted 20 December 2001 )

We present optical photometry, spectroscopy and photopolarimetry, as well as ASCA X-ray observations, of the recently discovered intermediate polar 1WGA J1958.2+3232. Through the first detection of an optical beat frequency, we confirm the previously tentative suggestion that the spin period of the white dwarf is twice the X-ray and optical pulsation period, which we also confirm in each case. We detect an orbital modulation in each of the U, B, V, R and I bands for the first time, and suggest that the true orbital period is the -1d alias of that previously suggested. We also confirm the presence of circular polarization in this system, detecting a variable polarization which has opposite signs in each of the B and R bands. The double peaked pulse profile and oppositely signed polarization pulses suggest that 1WGA J1958.2+3232 accretes onto both magnetic poles via a disc which is truncated relatively close to the white dwarf.

Key words: novae, cataclysmic variables -- stars: magnetic fields -- stars: individual -- 1WGA J1958.2+3232

Offprint request: A. J. Norton, A.J.Norton@open.ac.uk

SIMBAD Objects

© ESO 2002

What is OpenURL?

The OpenURL standard is a protocol for transmission of metadata describing the resource that you wish to access.

An OpenURL link contains article metadata and directs it to the OpenURL server of your choice. The OpenURL server can provide access to the resource and also offer complementary services (specific search engine, export of references...). The OpenURL link can be generated by different means.

  • If your librarian has set up your subscription with an OpenURL resolver, OpenURL links appear automatically on the abstract pages.
  • You can define your own OpenURL resolver with your EDPS Account.
    In this case your choice will be given priority over that of your library.
  • You can use an add-on for your browser (Firefox or I.E.) to display OpenURL links on a page (see http://www.openly.com/openurlref/). You should disable this module if you wish to use the OpenURL server that you or your library have defined.