Hostname: page-component-78c5997874-j824f Total loading time: 0 Render date: 2024-11-17T21:22:31.996Z Has data issue: false hasContentIssue false
  • English
  • Français

Transiting Planets in the Galactic Bulge from SWEEPS Survey and Implications

Published online by Cambridge University Press:  01 May 2008

Kailash C. Sahu ,
Stefano Casertano ,
Jeff Valenti ,
Howard E. Bond ,
Thomas M. Brown ,
T. Ed Smith ,
Will Clarkson ,
Dante Minniti ,
Manuela Zoccali  and
Mario Livio
...Show all authors
Kailash C. Sahu
Affiliation:
Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD. 21218, USA
Stefano Casertano
Affiliation:
Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD. 21218, USA
Jeff Valenti
Affiliation:
Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD. 21218, USA
Howard E. Bond
Affiliation:
Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD. 21218, USA
Thomas M. Brown
Affiliation:
Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD. 21218, USA
T. Ed Smith
Affiliation:
Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD. 21218, USA
Will Clarkson
Affiliation:
Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD. 21218, USA
Dante Minniti
Affiliation:
Universidad Catolica de Chile, Av. Vicua Mackenna 4860, Santiago, Chile
Manuela Zoccali
Affiliation:
Universidad Catolica de Chile, Av. Vicua Mackenna 4860, Santiago, Chile
Mario Livio
Affiliation:
Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD. 21218, USA
Alvio Renzini
Affiliation:
INAF - Osservatorio Astronomico di Padova, Vicolo dell'Osservatorio 5, 35122 Padova, Italy
R. M. Rich
Affiliation:
University of California at Los Angeles, Los Angeles, CA 90095-1562, USA
Nino Panagia
Affiliation:
Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD. 21218, USA
Stephen Lubow
Affiliation:
Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD. 21218, USA
Timothy Brown
Affiliation:
Las Cumbres Observatory Global Telescope, Goleta, CA
Nikolai Piskunov
Affiliation:
Department of Astronomy, Uppsala University, Box 515, 75120 Uppsala, Sweden
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The SWEEPS (Sagittarius Window Eclipsing Extrasolar Planet Search) program was aimed at detecting planets around stars in the Galactic bulge, not only to determine their physical properties, but also to determine whether the properties of planets found in the solar neighborhood, such as their frequency and the metallicity dependence, also hold for the planets in the Galactic bulge. We used the Hubble Space Telescope to monitor 180,000 F, G, K, and M dwarfs in the Galactic bulge continuously for 7 days in order to look for transiting planets. We discovered 16 candidate transiting extrasolar planets with periods of 0.6 to 4.2 days, including a possible new class of ultra-short period planets (USPPs) with P < 1 day. The facts that (i) the coverage in the monitoring program is continuous, (ii) most of the stars are at a known distance (in the Galctic bulge), (iii) monitoring was carried out in 2 passbands, and (iv) the images have high spatial resolution, were crucial in minimizing and estimating the false positive rates. We estimate that at least 45% of the candidates are genuine planets. Radial velocity observations of the two brightest host stars further support the planetary nature of the transiting companions. These results suggest that the planet frequency in the Galactic bulge is similar to that in the solar neighborhood. They also suggest that higher metallicity favors planet formation even in the Galactic bulge. The USPPs occur only around low-mass stars which may suggest that close-in planets around higher-mass stars are irradiately evaporated, or that planets are able to migrate to and survive in close-in orbits only around such old and low-mass stars.

Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 4 , Symposium S253: Transiting Planets , May 2008 , pp. 45 - 53
Copyright
Copyright © International Astronomical Union 2009

References

Alard, C. 1999, A& A, 343, 10Google Scholar
Bonfils, X. et al. 2005, A& A., 443, L15Google Scholar
Butler, R. P. et al. 2004; ApJ. 617, 580CrossRefGoogle Scholar
Clarkson, W. I. et al. 2008, ApJ, in pressGoogle Scholar
Fischer, D. A. & Valenti, J. A. 2005, ApJ, 622, 1102CrossRefGoogle Scholar
Fulbright, J. P., McWilliam, A., & Rich, R. M. 2006, 636, 821CrossRefGoogle Scholar
Gilliland, R. L. et al. 2000, ApJ, 545, L47CrossRefGoogle Scholar
Gilliland, R. L., Nugent, P. E., & Phillips, M. M. 1999, ApJ, 521, 30CrossRefGoogle Scholar
Gilliland, R. L. 2004, ACS Instrument Science Report, 2004-01 (Baltimore: STScI)Google Scholar
Kovacs, G., Zucker, S., & Mazeh, T., 2002, 391, 369CrossRefGoogle Scholar
Kuijken, K. & Rich, R. M. 2002, Astrophys. J. 124, 2054Google Scholar
Marcy, G. 2005, Prog. in Th. Phys. Suppl. 158, 24CrossRefGoogle Scholar
Rich, R. M. & Origlia, L.ApJ. 2005, 634, 1293Google Scholar
Sahu, K. C. et al. 2006, Nature, 443, 1038Google Scholar
Sahu, K. C. et al. 2008, in prep.Google Scholar
Sirianni, M. et al. 2005, PASP, 117, 1049CrossRefGoogle Scholar
Zoccali, M. et al. 2000, ApJ, 530, 418Google Scholar
Zoccali, M. et al. 2003, Astron. Astrophys. 399, 931Google Scholar