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تسجيل مستخدم جديدThe Frequency of Hot Jupiters in the Galaxy: Results from the SuperLupus Survey
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We present the results of the SuperLupus Survey for transiting hot Jupiter planets, which monitored a single Galactic disk field spanning 0.66 sq. deg for 108 nights over three years. Ten candidates were detected: one is a transiting planet, two remain candidates, and seven have been subsequently identified as false positives. We construct a new image quality metric, S_j, based on the behaviour of 26,859 light curves, which allows us to discard poor images in an objective and quantitative manner. Furthermore, in some cases we are able to identify statistical false positives by analysing temporal correlations between S_j and transit signatures. We use Monte Carlo simulations to measure our detection efficiency by injecting artificial transits onto real light curves and applying identical selection criteria as used in our survey. We find at 90% confidence level that 0.10 (+0.27/-0.08)% of dwarf stars host a hot Jupiter with a period of 1-10 days. Our results are consistent with other transit surveys, but appear consistently lower than the hot Jupiter frequencies reported from radial velocity surveys, a difference we attribute, at least in part, to the difference in stellar populations probed. In light of our determination of the frequency of hot Jupiters in Galactic field stars, previous null results for transiting planets in open cluster and globular cluster surveys no longer appear anomalously low.
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