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Assessing the capability of random forest to predict the evolution of enhanced gamma-ray states of active galactic nuclei

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 نشر من قبل Julian Sitarek
 تاريخ النشر 2021
  مجال البحث فيزياء
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Large fraction of studies of active galactic nuclei objects is based on performing follow-up observations using high-sensitivity instruments of high flux states observed by monitoring instruments (the so-called Target of Opportunity, ToO). Due to transient nature of such enhanced states it is essential to quickly evaluate if such a ToO event should be followed. We use a machine learning method to assess the possibility to predict the evolution of high flux states in gamma-ray band observed with Fermi-LAT in context of following such alerts with current and future Cherenkov telescopes. We probe flux and Test Statistic predictions using different training schemes and sample selections. We conclude that a partial prediction of the flux over a time scale of one day with an accuracy of ~35% is possible. The method provides accurate predictions of the raising/falling emission trend with 60 - 75% probability, however deeper investigations shows that this is likely based on typical properties of the source, rather than on the result of most recent measurements.

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