A fast hybrid algorithm for exoplanetary transit searches

A. Collier Cameron, D. Pollacco, R. A. Street, T. A. Lister, R. G. West, D. M. Wilson, F. Pont, D. J. Christian, W. I. Clarkson, B. Enoch, A. Evans, A. Fitzsimmons, C. A. Haswell, C. Hellier, S. T. Hodgkin, K. Horne, J. Irwin, S. R. Kane, F. P. Keenan, A. J. NortonN. R. Parley, J. Osborne, R. Ryans, I. Skillen, P. J. Wheatley

Research output: Contribution to journalArticle

140 Citations (Scopus)

Abstract

We present a fast and efficient hybrid algorithm for selecting exoplanetary candidates from wide-field transit surveys. Our method is based on the widely used SysRem and Box Least-Squares (BLS) algorithms. Patterns of systematic error that are common to all stars on the frame are mapped and eliminated using the SysRem algorithm. The remaining systematic errors caused by spatially localized flat-fielding and other errors are quantified using a boxcarsmoothing method. We show that the dimensions of the search-parameter space can be reduced greatly by carrying out an initial BLS search on a coarse grid of reduced dimensions, followed by Newton-Raphson refinement of the transit parameters in the vicinity of the most significant solutions. We illustrate the method's operation by applying it to data from one field of the SuperWASP survey, comprising 2300 observations of 7840 stars brighter than V = 13.0. We identify 11 likely transit candidates. We reject stars that exhibit significant ellipsoidal variations caused indicative of a stellar-mass companion. We use colours and proper motions from the Two Micron All Sky Survey and USNO-B1.0 surveys to estimate the stellar parameters and the companion radius. We find that two stars showing unambiguous transit signals pass all these tests, and so qualify for detailed high-resolution spectroscopic follow-up.

Original languageEnglish
Pages (from-to)799-810
Number of pages12
JournalMonthly Notices of the Royal Astronomical Society
Volume373
Issue number2
DOIs
Publication statusPublished - 1 Dec 2006
Externally publishedYes

Fingerprint

transit
stars
systematic errors
boxes
proper motion
stellar mass
newton
grids
color
radii
high resolution
estimates
method
parameter

Keywords

  • Methods: data analysis
  • Stars: planetary systems
  • Techniques: photometric

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

Collier Cameron, A., Pollacco, D., Street, R. A., Lister, T. A., West, R. G., Wilson, D. M., ... Wheatley, P. J. (2006). A fast hybrid algorithm for exoplanetary transit searches. Monthly Notices of the Royal Astronomical Society, 373(2), 799-810. https://doi.org/10.1111/j.1365-2966.2006.11074.x

A fast hybrid algorithm for exoplanetary transit searches. / Collier Cameron, A.; Pollacco, D.; Street, R. A.; Lister, T. A.; West, R. G.; Wilson, D. M.; Pont, F.; Christian, D. J.; Clarkson, W. I.; Enoch, B.; Evans, A.; Fitzsimmons, A.; Haswell, C. A.; Hellier, C.; Hodgkin, S. T.; Horne, K.; Irwin, J.; Kane, S. R.; Keenan, F. P.; Norton, A. J.; Parley, N. R.; Osborne, J.; Ryans, R.; Skillen, I.; Wheatley, P. J.

In: Monthly Notices of the Royal Astronomical Society, Vol. 373, No. 2, 01.12.2006, p. 799-810.

Research output: Contribution to journalArticle

Collier Cameron, A, Pollacco, D, Street, RA, Lister, TA, West, RG, Wilson, DM, Pont, F, Christian, DJ, Clarkson, WI, Enoch, B, Evans, A, Fitzsimmons, A, Haswell, CA, Hellier, C, Hodgkin, ST, Horne, K, Irwin, J, Kane, SR, Keenan, FP, Norton, AJ, Parley, NR, Osborne, J, Ryans, R, Skillen, I & Wheatley, PJ 2006, 'A fast hybrid algorithm for exoplanetary transit searches', Monthly Notices of the Royal Astronomical Society, vol. 373, no. 2, pp. 799-810. https://doi.org/10.1111/j.1365-2966.2006.11074.x
Collier Cameron A, Pollacco D, Street RA, Lister TA, West RG, Wilson DM et al. A fast hybrid algorithm for exoplanetary transit searches. Monthly Notices of the Royal Astronomical Society. 2006 Dec 1;373(2):799-810. https://doi.org/10.1111/j.1365-2966.2006.11074.x
Collier Cameron, A. ; Pollacco, D. ; Street, R. A. ; Lister, T. A. ; West, R. G. ; Wilson, D. M. ; Pont, F. ; Christian, D. J. ; Clarkson, W. I. ; Enoch, B. ; Evans, A. ; Fitzsimmons, A. ; Haswell, C. A. ; Hellier, C. ; Hodgkin, S. T. ; Horne, K. ; Irwin, J. ; Kane, S. R. ; Keenan, F. P. ; Norton, A. J. ; Parley, N. R. ; Osborne, J. ; Ryans, R. ; Skillen, I. ; Wheatley, P. J. / A fast hybrid algorithm for exoplanetary transit searches. In: Monthly Notices of the Royal Astronomical Society. 2006 ; Vol. 373, No. 2. pp. 799-810.
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T1 - A fast hybrid algorithm for exoplanetary transit searches

AU - Collier Cameron, A.

AU - Pollacco, D.

AU - Street, R. A.

AU - Lister, T. A.

AU - West, R. G.

AU - Wilson, D. M.

AU - Pont, F.

AU - Christian, D. J.

AU - Clarkson, W. I.

AU - Enoch, B.

AU - Evans, A.

AU - Fitzsimmons, A.

AU - Haswell, C. A.

AU - Hellier, C.

AU - Hodgkin, S. T.

AU - Horne, K.

AU - Irwin, J.

AU - Kane, S. R.

AU - Keenan, F. P.

AU - Norton, A. J.

AU - Parley, N. R.

AU - Osborne, J.

AU - Ryans, R.

AU - Skillen, I.

AU - Wheatley, P. J.

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KW - Methods: data analysis

KW - Stars: planetary systems

KW - Techniques: photometric

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