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Cyclotron modeling phase-resolved infrared spectroscopy of polars. III. AM Herculis and ST Leo Minoris

Campbell, R. K . and Harrison, T. E. and Kafka, S. (2008) Cyclotron modeling phase-resolved infrared spectroscopy of polars. III. AM Herculis and ST Leo Minoris. Astrophysical Journal, 683 (1). pp. 409-423. ISSN 0004-637X. doi:10.1086/589179.

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We present phase-resolved low-resolution infrared spectra of AM Her and ST LMi, two low-field polars that we observed with SPEX on the IRTF. Optical/NIR light curves are also published to help constrain the viewing geometry and brightness of the objects at the time they were observed. Currently, only limited IR spectra have been published for these objects, and none with the phase-coverage presented here. In both cases, the resulting spectra are dominated by emission from the secondary star in the NIR. However, the emission regions are also self-eclipsed, allowing us to isolate the cyclotron emission through subtraction of the dim-phase spectrum. We use a constant-lambda prescription to model the changing cyclotron features seen in the resulting data. For AM Her, we find a best-fit model of B = 13.6 MG, kT = 4.0 keV, and log Λ = 5.0. The cyclotron derived accretion geometry is consistent with i = 50° and β = 85°. For ST LMi, B = 12.1 MG, kT = 3.3 keV, and log Λ = 5.7, with i = 55° and β = 128°.

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Additional Information:© 2008. The American Astronomical Society. Received 2008 March 18; accepted 2008 April 9. Print publication: Issue 1 (2008 August 10). [R.K.C. was a] [v]isiting astronomer at the Infrared Telescope Facility (IRTF), which is operated by the University of Hawaii under a cooperative agreement with the National Aeronautics and Space Administration. [R.K.C. was] [s]upported by New Mexico State Space Grant. [T.E.H. was a] [v]isiting Astronomer, Kitt Peak National Observatory.
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University of HawaiiUNSPECIFIED
New Mexico State Space GrantUNSPECIFIED
Subject Keywords:novae, cataclysmic variables
Issue or Number:1
Record Number:CaltechAUTHORS:CAMapj08
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:13268
Deposited By: Ruth Sustaita
Deposited On:05 Feb 2009 20:38
Last Modified:08 Nov 2021 22:36

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