Colloquium Abstract - Sokolovsky - 2026Jan16

January 16, 2026

11:00am Mountain

Kirill Sokolovsky (TTU)

 

Galactic novae as shock-powered multi-messenger transients

 

Abstract

Accumulation of hydrogen-rich matter on the surface of a white dwarf accreting in a close binary system eventually leads to re-ignition of thermonuclear reactions. This temporarily revives the white dwarf as a shell-burning giant star. The process, observationally known as a nova, leads to dramatic optical brightening of the white dwarf-hosting binary by 8 to 18 magnitudes and is associated with ejection of the newly-formed white dwarf envelope at velocities of approximately 1000 km/s. For reasons that are not fully understood, the envelope ejection is not uniform, and shocks form within the ejecta. Shocks accelerate particles, producing synchrotron radio emission. Interaction of accelerated particles with dense ejecta produces the observed GeV to TeV gamma-rays and should make novae sources of high-energy neutrinos detectable with future neutrino observatories or with IceCube for a very nearby nova. Novae erupt in the Galaxy at a rate of about 30 per year, with only 10 typically being discovered. Our understanding of nova shocks comes primarily from detailed multi-wavelength observations of a handful of bright, nearby systems. Population-scale studies that could reveal systematic trends are challenging due to limited sensitivity and telescope time. I will discuss shock-related phenomena in novae from an observational perspective and highlight opportunities to learn more about shocks with current and future radio astronomy facilities.


Local Host: Justin Linford

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