Aviv Ofir, Stefan Dreizler
We use the SARS pipeline to search for planetary transits only in a small subset of the Kepler targets - the Kepler Objects of Interest (KOIs), which are already known to include at least one promising planet candidate. Although the KOIs represent less than 1% of the Kepler dataset we are able to significantly update the overall statistics of planetary multiplicity: we find 84 new transit signals on 64 systems on these light curves (LCs) only, nearly doubling the number of transit signals in these systems. 41 of the systems were singly-transiting systems that are now multiply-transiting, significantly reducing the chances of false positive in them. Notable among the new discoveries are KOI 435 as a new 6-candidate systems (where only Kepler-11 was known before), KOI 277 which includes two candidates in a 6:7 period commensurability and with anti-correlated TTVs -- all but validating the system, KOIs 719 and 1574 that have small planet candidates (1.29 R_Earth and 2.05 R_Earth respectively) in the habitable zone of their host star, and KOI 1843 that exhibits the shortest period (4.25hr) and among the smallest (0.68 R_Earth) of all planet candidates. We are also able to completely reject 11 KOIs as eclipsing binaries based on photometry alone, update the ephemeris for five KOIs and otherwise discuss a number of other objects, bringing the total of new signals and revised KOIs in this study to over a hundred. We discuss sub-optimal fitting of multi-transiting systems by the Kepler Mission that does not take Kepler's third law into account, causing the error on the d/R_* parameter to be overestimated by 3.8 (median factor). Interestingely about 1/3 of the newly detected candidates participate in period commensurabilities. We conclude that despite the phenomenal success of the Kepler mission, parallel analysis of the data by multiple teams is required to make full use of the data. [ABRIDGED]
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http://arxiv.org/abs/1206.5347
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