Quiescent and Active States of V1413 Aql I: Photometric Activity Criterion and the Detection of a Secondary Minimum

摘要

We present the results of our photometric UBV JHKL observations for the symbiotic star V1413 Aql obtained in 2012-2018. An analysis of the data has shown that inMay 2017 the system passed to a quiescent state with B - V approximate to 0(?) 6 for the first time since 1993. It lasted no more than five months. The J - K color at the primary minimum of 2012 reached 1(?) 5, which, given the interstellar reddening, corresponds to spectral type M5-M6 III of the cool component. A secondary minimum has been detected at phi approximate to 0.5 on the JK phase light curves constructed for the dates of observations with B 13.