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Small Telescope Exoplanet Transit Surveys: XO

  • Nicolas Crouzet
Living reference work entry

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Abstract

The XO project aims at detecting transiting exoplanets around bright stars from the ground using small telescopes. The original configuration of XO (McCullough et al. 2005) has been changed and extended as described here. The instrumental setup consists of three identical units located at different sites, each composed of two lenses equipped with CCD cameras mounted on the same mount. We observed two strips of the sky covering an area of 520∘2 for twice nine months. We build lightcurves for ∼20,000 stars up to magnitude R ≈ 12.5 using a custom-made photometric data reduction pipeline. The photometric precision is around 1–2% for most stars, and the large quantity of data allows us to reach a millimagnitude precision when folding the lightcurves on timescales that are relevant to exoplanetary transits. We search for periodic signals and identify several hundreds of variable stars and a few tens of transiting planet candidates. Follow-up observations are underway to confirm or reject these candidates. We found two close-in gas giant planets so far, in line with the expected yield.

Keywords

Exoplanets Transits Photometry Small instruments Time-series 

Notes

Acknowledgements

N.C. gratefully acknowledges Peter R. McCullough as the founder and principal investigator of the XO project. The XO project was supported by NASA grant NNX10AG30G. This research has made use of the Extrasolar Planets Encyclopaedia (exoplanet.eu), Simbad database (simbad.u-strasbg.fr/simbad/), astrometry.net software (Lang et al. 2010), and Stellar Photometry Software (Janes and Heasley 1993).

References

  1. Bakos G, Noyes RW, Kovács G et al. (2004) Wide-field millimagnitude photometry with the HAT: A tool for extrasolar planet detection. PASP 116:266–277Google Scholar
  2. Bakos GÁ, Lázár J, Papp I, Sári P Green EM (2002) System description and first light curves of the hungarian automated telescope, an autonomous observatory for variability search. PASP 114:974–987Google Scholar
  3. Bouchy F, Hébrard G, Udry S et al. (2009) The SOPHIE search for northern extrasolar planets. I. A companion around HD 16760 with mass close to the planet/brown-dwarf transition. A&A 505:853–858Google Scholar
  4. Burke CJ, McCullough PR, Valenti JA et al. (2007) XO-2b: transiting hot Jupiter in a metal-rich common proper motion binary. ApJ 671:2115–2128Google Scholar
  5. Burke CJ, McCullough PR, Valenti JA et al. (2008) XO-5b: A Transiting Jupiter-sized Planet with a 4 day Period. ApJ 686:1331–1340Google Scholar
  6. Collier Cameron A, Bouchy F, Hébrard G et al. (2007) WASP-1b and WASP-2b: two new transiting exoplanets detected with SuperWASP and SOPHIE. MNRAS 375:951–957Google Scholar
  7. Crouzet N, McCullough PR, Long D et al. (2017) Discovery of XO-6b: a hot Jupiter transiting a fast rotating F5 star on an oblique orbit. AJ 153:94Google Scholar
  8. Crouzet N, McCullough PR, Long D et al. (in prep) Discovery of XO-7bGoogle Scholar
  9. Janes KA Heasley JN (1993) Stellar photometry software. PASP 105:527–537Google Scholar
  10. Johns-Krull CM, McCullough PR, Burke CJ et al. (2008) XO-3b: a massive planet in an eccentric orbit transiting an F5 V star. ApJ 677:657–670Google Scholar
  11. Kovács G, Zucker S Mazeh T (2002) A box-fitting algorithm in the search for periodic transits. A&A 391:369–377Google Scholar
  12. Lang D, Hogg DW, Mierle K, Blanton M Roweis S (2010) Astrometry.net: blind astrometric calibration of arbitrary astronomical images. AJ 139:1782–1800Google Scholar
  13. McCullough PR, Stys JE, Valenti JA et al. (2005) The XO project: searching for transiting extrasolar planet candidates. PASP 117:783–795Google Scholar
  14. McCullough PR, Stys JE, Valenti JA et al. (2006) A transiting planet of a sun-like star. ApJ 648:1228–1238Google Scholar
  15. McCullough PR, Burke CJ, Valenti JA et al. (2008) XO-4b: an extrasolar planet transiting an F5V star. ArXiv e-printsGoogle Scholar
  16. Pollacco DL, Skillen I, Collier Cameron A et al. (2006) The WASP project and the SuperWASP cameras. PASP 118:1407–1418ADSCrossRefGoogle Scholar
  17. Ricker GR, Winn JN, Vanderspek R et al. (2014) Transiting exoplanet survey satellite (TESS). In: Space telescopes and instrumentation 2014: Optical, infrared, and millimeter wave. Proceedings of the SPIE, vol 9143, p 914320. http://doi.org/10.1117/12.2063489
  18. Santerne A, Moutou C, Tsantaki M et al. (2016) SOPHIE velocimetry of Kepler transit candidates. XVII. The physical properties of giant exoplanets within 400 days of period. A&A 587:A64Google Scholar
  19. Sullivan PW, Winn JN, Berta-Thompson ZK et al. (2015) The transiting exoplanet survey satellite: simulations of planet detections and astrophysical false positives. ApJ 809:77ADSCrossRefGoogle Scholar
  20. Tamuz O, Mazeh T Zucker S (2005) Correcting systematic effects in a large set of photometric light curves. MNRAS 356:1466–1470ADSCrossRefGoogle Scholar

Copyright information

© Springer International Publishing AG 2018

Authors and Affiliations

  1. 1.Instituto de Astrofísica de CanariasSan Cristóbal de La Laguna, Santa Cruz de TenerifeSpain

Section editors and affiliations

  • Norio Narita
    • 1
    • 2
    • 3
  1. 1.Graduate School of Science, Department of AstronomyUniversity of TokyoTokyoJapan
  2. 2.Exoplanet Detection Project OfficeNational Astronomical Observatory of JapanTokyoJapan
  3. 3.Exoplanet Detection Project OfficeAstrobiology CenterTokyoJapan

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