![]() |
|
||
Home Astronomy research Software Infrastructure: MESA FLASH STARLIB MESA-Web starkiller-astro My instruments White dwarf supernova: Remnant metallicities Colliding white dwarfs Merging white dwarfs Ignition conditions Metallicity effects Central density effects Detonation density effects Tracer particle burning Subsonic burning fronts Supersonic burning fronts W7 profiles Massive star supernova: Rotating progenitors 3D evolution 26Al & 60Fe 44Ti, 60Co & 56Ni Yields of radionuclides Effects of 12C +12C SN 1987A light curve Constraints on Ni/Fe ratios An r-process Neutron Stars and Black Holes: Black Hole Mass Gap Compact object IMF Stars: Neutrino HR diagram Pulsating white dwarfs Pop III with JWST Monte Carlo massive stars Neutrinos from pre-SN Pre-SN variations Monte Carlo white dwarfs SAGB stars Classical novae He shell convection Presolar grains He burn on neutron stars BBFH at 40 years Chemical Evolution: Iron Pseudocarbynes Radionuclides in the 2020s Hypatia catalog Zone models H to Zn Mixing ejecta γ-rays within 100 Mpc Thermodynamics & Networks Stellar EOS 12C(α,γ)16O Rate Proton-rich NSE Reaction networks Bayesian reaction rates Verification Problems: Validating an astro code Su-Olson Cog8 Mader RMTV Sedov Noh Software instruments Presentations Illustrations cococubed YouTube Bicycle adventures Public Outreach Education materials 2022 ASU Solar Systems Astronomy 2022 ASU Energy in Everyday Life AAS Journals AAS YouTube 2022 Earendel, A Highly Magnified Star 2022 TV Columbae, Micronova 2022 MESA in Don't Look Up 2022 MESA Marketplace 2022 MESA Summer School 2022 MESA Classroom 2021 Bill Paxton, Tinsley Prize Contact: F.X.Timmes my one page vitae, full vitae, research statement, and teaching statement. |
Localized thermonuclear bursts from accreting magnetic white dwarfs
(2022)
Nova explosions are caused by global thermonuclear runaways triggered in the surface layers of accreting white dwarfs. It has been predicted that localised thermonuclear bursts on white dwarfs can also take place, similar to Type I X-ray bursts observed in accreting neutron stars. Unexplained rapid bursts from the binary system TV Columbae, in which mass is accreted onto a moderately-strong magnetised white dwarf from a low-mass companion, have been observed on several occasions in the past ≈40 years. During these bursts the optical/UV luminosity increases by a factor of >3 in less than an hour and fades over ≈10 hours. Fast outflows have been observed in UV spectral lines$^{7}$, with velocities >3500 km/s, comparable to the escape velocity from the white dwarf surface. In this article, we report on optical bursts observed in TV Columbae as well as in two additional accreting systems, EI Ursae Majoris and ASASSN$-$19bh. The bursts have a total energy ≈10-6 those of classical nova explosions ("micronovae"), and bear a strong resemblance to Type I X-ray bursts. We exclude accretion or stellar magnetic reconnection events as their origin and suggest thermonuclear runaway events in magnetically-confined accretion columns as a viable explanation. This article, made some news and some more news. |
||
|
---|