Details

Autor(en) / Beteiligte

• Luna, G. J. M.
• Mukai, K.
• Sokoloski, J. L.
• Nelson, T.
• Kuin, P.
• Segreto, A.
• Cusumano, G.
• Jaque Arancibia, M.
• Nuñez, N. E.

Titel

Dramatic change in the boundary layer in the symbiotic recurrent nova T Coronae Borealis

Ist Teil von

• Astronomy and astrophysics (Berlin), 2018-11, Vol.619, p.A61

Ort / Verlag

Heidelberg: EDP Sciences

Erscheinungsjahr

2018

Quelle

Elektronische Zeitschriftenbibliothek - Frei zugängliche E-Journals

Beschreibungen/Notizen

• A sudden increase in the rate at which material reaches the most internal part of an accretion disk, i.e., the boundary layer, can change its structure dramatically. We have witnessed such a change for the first time in the symbiotic recurrent nova T CrB. Our analysis of XMM-Newton, Swift Burst Alert Telescope (BAT)/X-Ray Telescope (XRT)/UltraViolet Optical Telescope (UVOT), and the American Association of Variable Stars Observers (AAVSO) V- and B-band data indicates that during an optical brightening event that started in early 2014 (ΔV ≈ 1.5) the following occurred: (i) the hard X-ray emission as seen with BAT almost vanished; (ii) the XRT X-ray flux decreased significantly, while the optical flux remained high; (iii) the UV flux increased by at least a factor of 40 over the quiescent value; and (iv) the X-ray spectrum became much softer and a bright, new blackbody-like component appeared. We suggest that the optical brightening event, which could be a similar event to that observed about 8 years before the most recent thermonuclear outburst in 1946, is due to a disk instability.