Show simple item record

dc.contributor.authorPotter, S.B.
dc.contributor.authorCropper, M.
dc.contributor.authorMason, K.O.
dc.contributor.authorHough, J.
dc.contributor.authorBailey, J.
dc.identifier.citationPotter , S B , Cropper , M , Mason , K O , Hough , J & Bailey , J 1997 , ' Simultaneous UBVRIJK photometric and polarimetric observations of PQ Gem ' , Monthly Notices of the Royal Astronomical Society , vol. 285 , no. 1 , pp. 82-94 .
dc.identifier.otherPURE: 166732
dc.identifier.otherPURE UUID: 76ddb906-4d58-4adf-84a3-7674bf3d333c
dc.identifier.otherdspace: 2299/3257
dc.identifier.otherScopus: 0002691322
dc.descriptionOriginal article can be found via: Copyright Royal Astronomical Society [Full text of this article is not available in the UHRA]
dc.description.abstractWe present simultaneous UBVRIJK observations of the intermediate polar PQ Gem (RE J0751+14) obtained on 1993 February 18 and 19 using the Hatfield Polarimeter on UKIRT. The light curves show double- peaked modulation on the spin period at the longer wavelengths and become single-peaked at the shorter wavelengths. Both positive and negative circular polarizations are detected on the spin period in the V to K bands, confirming previous observations by Piirola, Hakala & Coyne and suggesting emission from two magnetic poles. We present model light curves of cyclotron emission from opposite poles of a centred inclined magnetic dipole. Optimal results are obtained for an inclination of ~60 deg and a magnetic dipole offset of ~30 deg. Our model of cyclotron emission from two extended arc-shaped accretion shock regions explains the dip in the negative polarization as absorption or scattering of the cyclotron radiation by the accretion column. This occurs when the accretion region in the upper hemisphere traverses the line of sight. A wavelength- independent intensity minimum occurs half of a spin cycle later when this region passes over the limb on the white dwarf. This model is inverted with respect to that proposed by Piirola et al. and Vath et al., and is more consistent with the X-ray observations. The arcs are placed ahead of the magnetic poles, and we argue that this is consistent with the recently reported spin-down of this system. Our best estimate of the magnetic field at the pole is B_0~9-21MG, depending on the optical depth parameter used.en
dc.relation.ispartofMonthly Notices of the Royal Astronomical Society
dc.subjectmagnetic accretion columns
dc.subjectcataclysmic variables
dc.titleSimultaneous UBVRIJK photometric and polarimetric observations of PQ Gemen
dc.contributor.institutionSchool of Physics, Astronomy and Mathematics
dc.description.statusPeer reviewed
dc.relation.schoolSchool of Physics, Astronomy and Mathematics
rioxxterms.typeJournal Article/Review

Files in this item


There are no files associated with this item.

This item appears in the following Collection(s)

Show simple item record