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arXiv · 1405.7525

Mid- and Far-Infrared Variability of PV Cep

Dario Lorenzetti·Simone Antoniucci·Teresa Giannini·Gianluca Li Causi·Andrea Di Paola·Arkady A. Arkharov·Valeri M. Larionov
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Abstract

We present the collection of all the mid- and far-IR observations (3-170 um) of the young eruptive variable PV Cep available so far in the literature. These data allow us to confirm that flux variability is a prominent feature at mid-IR wavelength (3-25 um). Color-magnitude plots clearly indicate that the observed variability is not extinction-driven, but mainly influenced by fluctuations of the mass accretion rate. We interpret such variability as due to a hot spot created onto the stellar surface by the column of accreting matter, which heats the inner parts of the disk and determines the observed increase of the near- mid-IR luminosity. A quantitative characterization is given for both the spot itself and the additional thermal component created by it. Far-IR data (60-170 um) are consistent with the presence of a temperature stratification in a massive and quite un-evolved circumstellar disk.

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Dario Lorenzetti, Simone Antoniucci, Teresa Giannini, Gianluca Li Causi, Andrea Di Paola, Arkady A. Arkharov, Valeri M. Larionov. 2014-05-29. Mid- and Far-Infrared Variability of PV Cep. https://doi.org/10.1007/s10509-014-2044-2

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