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Title: First detection of multi-shocks in RR Lyrae stars from Antarctica : A possible explanation of the Blazhko effect

We present the first detection of multi-shocks propagating through the atmosphere of the Blazhko star S Arae using uninterrupted, accurate optical photometric data collected during one polar night, 150 days from Antarctica at Dome C, with the Photometer AntarctIca eXtinction (PAIX). We acquired 89,736 CCD frames during 323 pulsation cycles and 3 Blazhko cycles. We detected two new light curve properties in the PAIX light curve, jump and rump, which we associated with two new post-maximum shock waves Sh{sub PM1} and Sh{sub PM2}. jump, lump, rump, bump, and hump are induced by five shock waves, with different amplitudes and origins, Sh{sub PM1}, Sh{sub PM}, Sh{sub PM2}, Sh{sub PM3}, and the main shock Sh{sub H+He}. Correlations between the length of rise time and light amplitude and Sh{sub PM3} are monotonous during three Blazhko cycles, but the pulsation curve is double peaked. We discuss the physical mechanisms driving the modulation of these quantities. Finally, we hypothesize that the origin of the Blazhko effect is a dynamical interaction between a multi-shock structure and an outflowing wind in a coronal structure.
Authors:
; ; ; ; ; ; ;  [1] ;  [2] ;  [3] ;  [4]
  1. Université Nice Sophia-Antipolis, Observatoire de la Côte d'Azur, UMR 7293, Parc Valrose, F-06108 Nice Cedex 02 (France)
  2. Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)
  3. National Astronomical Observatories, Chinese Academy of Sciences, 20A Datun Road, Chaoyang District, Beijing (China)
  4. DGA Matrise de l'Information, BP 7, F-35998 Rennes Armees (France)
Publication Date:
OSTI Identifier:
22342231
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (New York, N.Y. Online); Journal Volume: 148; Journal Issue: 5; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AMPLITUDES; ANTARCTICA; CHARGE-COUPLED DEVICES; CORRELATIONS; DETECTION; HYDRODYNAMICS; INTERACTIONS; MODULATION; OSCILLATIONS; PHOTOMETERS; PULSATIONS; PULSE RISE TIME; SHOCK WAVES; STARS; VISIBLE RADIATION