Polarimetric evolution of V838 Mon

• Main Authors: Desidera, S, Giro, E, Munari, U, Efimov, Y. S, Henden, A, Benetti, S, Tomov, T, Bianchini, A, Pernechele, C
• Format: Journal Article
• Language: English
• Published: 03-10-2003
• Subjects: Physics - Astrophysics of Galaxies; Physics - Cosmology and Nongalactic Astrophysics; Physics - Earth and Planetary Astrophysics; Physics - High Energy Astrophysical Phenomena; Physics - Instrumentation and Methods for Astrophysics; Physics - Solar and Stellar Astrophysics
• DOI: 10.48550/arxiv.astro-ph/0310092

Astron.Astrophys. 414 (2004) 591-600 We present the results of our polarimetric and spectropolarimetric monitoring
of V838 Monocerotis, performed at Asiago and Crimean observatories during and
after the multiple outbursts that occurred in January-March 2002.
The polarization of the object is mainly due to interstellar polarization
(P=2.48%). Intrinsic polarization up to 0.7% at 5000 A is present during the
second maximum of the object (February 2002). This intrinsic component
increases toward shorter wavelengths but our limited spectral coverage
(5000-7500 A) does not allow conclusive inferences about its origin. A strong
depolarization across the Halpha profile is observed. The interstellar
polarization gives a lower limit to the reddening of E(B-V)>0.28, with
E(B-V)=0.5 being the most probable value. A normal ratio of total to selective
absorption (R_V=3.22+-0.17) was derived from the wavelength of maximum
interstellar polarization. This suggests a low (if any) contribution by
circumstellar material with peculiar dust to gas ratio. A polarimetric map of a
portion of the light echo shows a complex polarization distribution reaching
P_max=45%.