Submitting Campus
Daytona Beach
Department
Physical Sciences
Document Type
Article
Publication/Presentation Date
4-18-2020
Abstract/Description
We have made high-precision polarimetric observations of the polluted white dwarf G29-38 with the HIgh Precision Polarimetric Instrument 2. The observations were made at two different observatories – using the 8.1-m Gemini North Telescope and the 3.9-m Anglo-Australian Telescope – and are consistent with each other. After allowing for a small amount of interstellar polarization, the intrinsic linear polarization of the system is found to be 275.3 ± 31.9 parts per million at a position angle of 90.8 ± 3.8◦ in the SDSS g
band. We compare the observed polarization with the predictions of circumstellar disc models. The measured polarization is small in the context of the models we develop, which only allows us to place limits on disc inclination and Bond albedo for optically thin disc geometries. In this case, either the inclination is near-face-on or the albedo is small – likely in the range 0.05–0.15 – which is in line with other debris disc measurements. A preliminary search for the effects of G29-38’s pulsations in the polarization signal produced inconsistent results. This may be caused by beating effects, indicate a clumpy dust distribution, or be a consequence of measurement systematics.
Publication Title
Monthly Notices of the Royal Astronomical Society
DOI
https://doi.org/10.1093/mnras/staa1023
Publisher
The Royal Astronomical Society
Grant or Award Name
NSF Grant AST-1715718, Ministry of Science and Technology of Taiwan grants MOST104-2628-M001-004-MY3 and MOST107-2119-M001-031-MY3, Academia Sinica grant AS-IA-106-M03
Scholarly Commons Citation
Hippel, T. v., Cotton, D. V., Bailey, J., Pringle, J., Sparks, W. B., & Marshall, J. P. (2020). Polarization Measurements of the Polluted White Dwarf G29-38. Monthly Notices of the Royal Astronomical Society, 494(4). https://doi.org/10.1093/mnras/staa1023
