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The Cluster AgeS Experiment (CASE). Detecting Photometric Variability with the Friends of Friends Algorithm

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 نشر من قبل Michal Rozyczka
 تاريخ النشر 2018
  مجال البحث فيزياء
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We adapt the friends of friends algorithm to the analysis of light curves, and show that it can be successfully applied to searches for transient phenomena in large photometric databases. As a test case we search OGLE-III light curves for known dwarf novae. A single combination of control parameters allows to narrow the search to 1% of the data while reaching a $sim$90% detection efficiency. A search involving $sim$2% of the data and three combinations of control parameters can be significantly more effective - in our case a 100% efficiency is reached. The method can also quite efficiently detect semi-regular or strictly periodic variability. We report 28 new variables found in the field of the globular cluster M22, which was examined earlier with the help of periodicity-searching algorithms



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