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Title: Fast-rising blue optical transients and AT2018cow following electron-capture collapse of merged white dwarfs

Abstract

Abstract We suggest that fast-rising blue optical transients (FBOTs) and the brightest event of the class, AT2018cow, result from an electron-capture collapse to a neutron star following the merger of a massive ONeMg white dwarf (WD) with another WD. Two distinct evolutionary channels lead to the disruption of the less-massive WD during the merger and the formation of a shell-burning non-degenerate star incorporating the ONeMg core. During the shell-burning stage, a large fraction of the envelope is lost to the wind, while mass and angular momentum are added to the core. As a result, the electron-capture collapse occurs with a small envelope mass, after ∼102–104 yr. During the formation of a neutron star, as little as $${\sim } 10^{-2} \, \mathrm{M}_\odot$$ of the material is ejected at the bounce-off with mildly relativistic velocities and total energy of about a few 1050 erg. This ejecta becomes optically thin on a time-scale of days – this is the FBOT. During the collapse, the neutron star is spun up and the magnetic field is amplified. The ensuing fast magnetically dominated relativistic wind from the newly formed neutron star shocks against the ejecta, and later against the wind. The radiation-dominated forward shock produces the long-lasting optical afterglow, while the termination shock of the relativistic wind produces the high-energy emission in a manner similar to pulsar wind nebulae. If the secondary WD was of the DA type, the wind will likely have $${\sim } 10^{-4} \, \mathrm{M}_\odot$$ of hydrogen; this explains the appearance of hydrogen late in the afterglow spectrum. The model explains many of the puzzling properties of FBOTs/AT2018cow: host galaxies, a fast and light anisotropic ejecta producing a bright optical peak, afterglow high-energy emission of similar luminosity to the optical, and late infrared features.

Authors:
 [1];  [2]
  1. Department of Physics and Astronomy, Purdue University, 525 Northwestern Avenue, West Lafayette, IN 47907-2036, USA
  2. Anton Pannekoek Institute for Astronomy, University of Amsterdam, PO Box 94249, 1090 GE, Amsterdam, the Netherlands
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1530651
Grant/Contract Number:  
SC0016369
Resource Type:
Published Article
Journal Name:
Monthly Notices of the Royal Astronomical Society
Additional Journal Information:
Journal Name: Monthly Notices of the Royal Astronomical Society Journal Volume: 487 Journal Issue: 4; Journal ID: ISSN 0035-8711
Publisher:
Oxford University Press
Country of Publication:
United Kingdom
Language:
English

Citation Formats

Lyutikov, Maxim, and Toonen, Silvia. Fast-rising blue optical transients and AT2018cow following electron-capture collapse of merged white dwarfs. United Kingdom: N. p., 2019. Web. doi:10.1093/mnras/stz1640.
Lyutikov, Maxim, & Toonen, Silvia. Fast-rising blue optical transients and AT2018cow following electron-capture collapse of merged white dwarfs. United Kingdom. doi:10.1093/mnras/stz1640.
Lyutikov, Maxim, and Toonen, Silvia. Tue . "Fast-rising blue optical transients and AT2018cow following electron-capture collapse of merged white dwarfs". United Kingdom. doi:10.1093/mnras/stz1640.
@article{osti_1530651,
title = {Fast-rising blue optical transients and AT2018cow following electron-capture collapse of merged white dwarfs},
author = {Lyutikov, Maxim and Toonen, Silvia},
abstractNote = {Abstract We suggest that fast-rising blue optical transients (FBOTs) and the brightest event of the class, AT2018cow, result from an electron-capture collapse to a neutron star following the merger of a massive ONeMg white dwarf (WD) with another WD. Two distinct evolutionary channels lead to the disruption of the less-massive WD during the merger and the formation of a shell-burning non-degenerate star incorporating the ONeMg core. During the shell-burning stage, a large fraction of the envelope is lost to the wind, while mass and angular momentum are added to the core. As a result, the electron-capture collapse occurs with a small envelope mass, after ∼102–104 yr. During the formation of a neutron star, as little as ${\sim } 10^{-2} \, \mathrm{M}_\odot$ of the material is ejected at the bounce-off with mildly relativistic velocities and total energy of about a few 1050 erg. This ejecta becomes optically thin on a time-scale of days – this is the FBOT. During the collapse, the neutron star is spun up and the magnetic field is amplified. The ensuing fast magnetically dominated relativistic wind from the newly formed neutron star shocks against the ejecta, and later against the wind. The radiation-dominated forward shock produces the long-lasting optical afterglow, while the termination shock of the relativistic wind produces the high-energy emission in a manner similar to pulsar wind nebulae. If the secondary WD was of the DA type, the wind will likely have ${\sim } 10^{-4} \, \mathrm{M}_\odot$ of hydrogen; this explains the appearance of hydrogen late in the afterglow spectrum. The model explains many of the puzzling properties of FBOTs/AT2018cow: host galaxies, a fast and light anisotropic ejecta producing a bright optical peak, afterglow high-energy emission of similar luminosity to the optical, and late infrared features.},
doi = {10.1093/mnras/stz1640},
journal = {Monthly Notices of the Royal Astronomical Society},
number = 4,
volume = 487,
place = {United Kingdom},
year = {2019},
month = {7}
}

Journal Article:
Free Publicly Available Full Text
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DOI: 10.1093/mnras/stz1640

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Cited by: 7 works
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Works referenced in this record:

Three-dimensional simulations of neutrino-driven core-collapse supernovae from low-mass single and binary star progenitors
journal, January 2019

  • Müller, Bernhard; Tauris, Thomas M.; Heger, Alexander
  • Monthly Notices of the Royal Astronomical Society, Vol. 484, Issue 3
  • DOI: 10.1093/mnras/stz216

Double white dwarfs as progenitors of R Coronae Borealis stars and Type I supernovae
journal, February 1984

  • Webbink, R. F.
  • The Astrophysical Journal, Vol. 277
  • DOI: 10.1086/161701

Shock-wave propagation in the nonuniform interstellar medium
journal, July 1995


The effect of common-envelope evolution on the visible population of post-common-envelope binaries
journal, September 2013


Monte Carlo simulations of relativistic radiation-mediated shocks – I. Photon-rich regime
journal, October 2017

  • Ito, Hirotaka; Levinson, Amir; Stern, Boris E.
  • Monthly Notices of the Royal Astronomical Society, Vol. 474, Issue 2
  • DOI: 10.1093/mnras/stx2722

What Can the Accretion‐induced Collapse of White Dwarfs Really Explain?
journal, May 1999

  • Fryer, Chris; Benz, Willy; Herant, Marc
  • The Astrophysical Journal, Vol. 516, Issue 2
  • DOI: 10.1086/307119

PSR B1745−20 and Young Pulsars in Globular Clusters
journal, March 1996

  • Lyne, A. G.; Manchester, R. N.; D'Amico, N.
  • The Astrophysical Journal, Vol. 460, Issue 1
  • DOI: 10.1086/309972

Observational Clues to the Progenitors of Type Ia Supernovae
journal, August 2014


The Effects of Binary Evolution on the Dynamics of Core Collapse and Neutron Star Kicks
journal, September 2004

  • Podsiadlowski, Ph.; Langer, N.; Poelarends, A. J. T.
  • The Astrophysical Journal, Vol. 612, Issue 2
  • DOI: 10.1086/421713

The conductive propagation of nuclear flames. I - Degenerate C + O and O + NE + MG white dwarfs
journal, September 1992

  • Timmes, F. X.; Woosley, S. E.
  • The Astrophysical Journal, Vol. 396
  • DOI: 10.1086/171746

Presupernova Evolution of Massive Single and Binary Stars
journal, September 2012


Supernova ptf 09uj: a Possible Shock Breakout from a Dense Circumstellar wind
journal, November 2010


Do electron-capture supernovae make neutron stars?: First multidimensional hydrodynamic simulations of the oxygen deflagration
journal, September 2016


Multidimensional simulations of ultrastripped supernovae to shock breakout
journal, June 2018

  • Müller, Bernhard; Gay, Daniel W.; Heger, Alexander
  • Monthly Notices of the Royal Astronomical Society, Vol. 479, Issue 3
  • DOI: 10.1093/mnras/sty1683

The fast, luminous ultraviolet transient AT2018cow: extreme supernova, or disruption of a star by an intermediate-mass black hole?
journal, December 2018

  • Perley, Daniel A.; Mazzali, Paolo A.; Yan, Lin
  • Monthly Notices of the Royal Astronomical Society, Vol. 484, Issue 1
  • DOI: 10.1093/mnras/sty3420

Relativistic Radiation Mediated Shocks
journal, November 2010


AT2018cow: A Luminous Millimeter Transient
journal, January 2019

  • Ho, Anna Y. Q.; Phinney, E. Sterl; Ravi, Vikram
  • The Astrophysical Journal, Vol. 871, Issue 1
  • DOI: 10.3847/1538-4357/aaf473

Radiation- and pair-loaded shocks
journal, April 2018

  • Lyutikov, Maxim
  • Monthly Notices of the Royal Astronomical Society, Vol. 477, Issue 1
  • DOI: 10.1093/mnras/sty735

Origin of the Binary Pulsar J0737-3039B
journal, February 2005


The demographics of neutron star – white dwarf mergers: Rates, delay-time distributions, and progenitors
journal, November 2018


Common envelope evolution: where we stand and how we can move forward
journal, February 2013


The Cosmic Core-Collapse Supernova rate does not Match the Massive-Star Formation rate
journal, August 2011

  • Horiuchi, Shunsaku; Beacom, John F.; Kochanek, Christopher S.
  • The Astrophysical Journal, Vol. 738, Issue 2
  • DOI: 10.1088/0004-637X/738/2/154

Supernovae of type I as end products of the evolution of binaries with components of moderate initial mass (M not greater than about 9 solar masses)
journal, January 1984

  • Iben, I. , Jr.; Tutukov, A. V.
  • The Astrophysical Journal Supplement Series, Vol. 54
  • DOI: 10.1086/190932

A large-scale dynamo and magnetoturbulence in rapidly rotating core-collapse supernovae
journal, November 2015

  • Mösta, Philipp; Ott, Christian D.; Radice, David
  • Nature, Vol. 528, Issue 7582
  • DOI: 10.1038/nature15755

Fast and Luminous Transients from the Explosions of Long-lived Massive White Dwarf Merger Remnants
journal, November 2017

  • Brooks, Jared; Schwab, Josiah; Bildsten, Lars
  • The Astrophysical Journal, Vol. 850, Issue 2
  • DOI: 10.3847/1538-4357/aa9568

The electromagnetic model of gamma-ray bursts
journal, July 2006


The spectrum of a fast shock breakout from a stellar wind
journal, January 2019

  • Ioka, Kunihito; Levinson, Amir; Nakar, Ehud
  • Monthly Notices of the Royal Astronomical Society, Vol. 484, Issue 3
  • DOI: 10.1093/mnras/stz270

Erratum: Thermal runaway during the evolution of ONeMg cores towards accretion-induced collapse
journal, March 2016

  • Schwab, Josiah; Quataert, Eliot; Bildsten, Lars
  • Monthly Notices of the Royal Astronomical Society, Vol. 458, Issue 4
  • DOI: 10.1093/mnras/stw560

Merging white dwarfs and Type Ia supernovae
journal, October 2016

  • Yungelson, L. R.; Kuranov, A. G.
  • Monthly Notices of the Royal Astronomical Society, Vol. 464, Issue 2
  • DOI: 10.1093/mnras/stw2432

ULTRA-STRIPPED TYPE Ic SUPERNOVAE FROM CLOSE BINARY EVOLUTION
journal, November 2013


Delay-time distribution of core-collapse supernovae with late events resulting from binary interaction
journal, April 2017


GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral
journal, October 2017


The opacity of expanding media - The effect of spectral lines
journal, May 1977

  • Karp, A. H.; Lasher, G.; Chan, K. L.
  • The Astrophysical Journal, Vol. 214
  • DOI: 10.1086/155241

Ultra-stripped supernovae: progenitors and fate
journal, June 2015

  • Tauris, Thomas M.; Langer, Norbert; Podsiadlowski, Philipp
  • Monthly Notices of the Royal Astronomical Society, Vol. 451, Issue 2
  • DOI: 10.1093/mnras/stv990

Carbon ignition in a rapidly accreting degenerate dwarf - A clue to the nature of the merging process in close binaries
journal, October 1985

  • Nomoto, K.; Iben, I. , Jr.
  • The Astrophysical Journal, Vol. 297
  • DOI: 10.1086/163547

Radio supernovae
journal, February 1986

  • Weiler, K. W.; Sramek, R. A.; Panagia, N.
  • The Astrophysical Journal, Vol. 301
  • DOI: 10.1086/163944

The common envelope phase in the evolution of binary stars
journal, June 1988

  • Livio, Mario; Soker, Noam
  • The Astrophysical Journal, Vol. 329
  • DOI: 10.1086/166419

PopCORN: Hunting down the differences between binary population synthesis codes
journal, January 2014


The Long-Term Evolution of Double White Dwarf Mergers
journal, March 2012


Type I supernovae. I - Analytic solutions for the early part of the light curve
journal, February 1982

  • Arnett, W. D.
  • The Astrophysical Journal, Vol. 253
  • DOI: 10.1086/159681

Synchrotron Self‐Absorption in Radio Supernovae
journal, June 1998

  • Chevalier, Roger A.
  • The Astrophysical Journal, Vol. 499, Issue 2
  • DOI: 10.1086/305676

An Embedded X-Ray Source Shines through the Aspherical AT 2018cow: Revealing the Inner Workings of the Most Luminous Fast-evolving Optical Transients
journal, February 2019


Crab nebula gamma-ray flares as relativistic reconnection minijets: Crab flares as minijets
journal, October 2012


Double-degenerate Carbon–Oxygen and Oxygen–Neon White Dwarf Mergers: A New Mechanism for Faint and Rapid Type Ia Supernovae
journal, December 2018

  • Kashyap, Rahul; Haque, Tazkera; Lorén-Aguilar, Pablo
  • The Astrophysical Journal, Vol. 869, Issue 2
  • DOI: 10.3847/1538-4357/aaedb7

Explosions of O-Ne-Mg cores, the Crab supernova, and subluminous type II-P supernovae
journal, April 2006


The structure and fate of white dwarf merger remnants
journal, December 2013

  • Dan, Marius; Rosswog, Stephan; Brüggen, Marcus
  • Monthly Notices of the Royal Astronomical Society, Vol. 438, Issue 1
  • DOI: 10.1093/mnras/stt1766

The Physics of Type Ia Supernova Light Curves. II. Opacity and Diffusion
journal, February 2000

  • Pinto, Philip A.; Eastman, Ronald G.
  • The Astrophysical Journal, Vol. 530, Issue 2
  • DOI: 10.1086/308380

On the formation of neutron stars via accretion-induced collapse in binaries
journal, January 2019

  • Ruiter, A. J.; Ferrario, L.; Belczynski, K.
  • Monthly Notices of the Royal Astronomical Society, Vol. 484, Issue 1
  • DOI: 10.1093/mnras/stz001

Simulations of the Boundary Layer Between a White Dwarf and its Accretion disk
journal, August 2009


Spread of matter over a neutron-star surface during disk accretion: Deceleration of rapid rotation
journal, December 2010


Angular Momentum Transport by Acoustic Modes Generated in the Boundary Layer. i. Hydrodynamical Theory and Simulations
journal, May 2013

  • Belyaev, Mikhail A.; Rafikov, Roman R.; Stone, James M.
  • The Astrophysical Journal, Vol. 770, Issue 1
  • DOI: 10.1088/0004-637X/770/1/67

Rotating Magnetospheres: an Exact 3-D Solution
journal, March 1973

  • Michel, F. Curtis
  • The Astrophysical Journal, Vol. 180
  • DOI: 10.1086/181169

Conditions for accretion-induced collapse of white dwarfs
journal, January 1991

  • Nomoto, Ken'ichi; Kondo, Yoji
  • The Astrophysical Journal, Vol. 367
  • DOI: 10.1086/185922

The Cow: Discovery of a Luminous, Hot, and Rapidly Evolving Transient
journal, September 2018

  • Prentice, S. J.; Maguire, K.; Smartt, S. J.
  • The Astrophysical Journal, Vol. 865, Issue 1
  • DOI: 10.3847/2041-8213/aadd90

Supernova Type Ia progenitors from merging double white dwarfs: Using a new population synthesis model⋆
journal, October 2012


Spreading Layers in Accreting Objects: role of Acoustic Waves for Angular Momentum Transport, Mixing, and Thermodynamics
journal, January 2016

  • Philippov, Alexander A.; Rafikov, Roman R.; Stone, James M.
  • The Astrophysical Journal, Vol. 817, Issue 1
  • DOI: 10.3847/0004-637X/817/1/62

Star Formation, Supernovae, Iron, and α : Consistent Cosmic and Galactic Histories
journal, October 2017


Type Ia Supernovae: Influence of the Initial Composition on the Nucleosynthesis, Light Curves, and Spectra and Consequences for the Determination of Ω M and Λ
journal, March 1998

  • Höflich, P.; Wheeler, J. C.; Thielemann, F. K.
  • The Astrophysical Journal, Vol. 495, Issue 2
  • DOI: 10.1086/305327

The structure of supernova shock waves
journal, October 1976

  • Weaver, T. A.
  • The Astrophysical Journal Supplement Series, Vol. 32
  • DOI: 10.1086/190398

The collapse of white dwarfs to neutron stars
journal, May 1992

  • Woosley, S. E.; Baron, E.
  • The Astrophysical Journal, Vol. 391
  • DOI: 10.1086/171338

Binary pulsar J0737−3039 – evidence for a new core collapse and neutron star formation mechanism
journal, January 2014

  • Dall'Osso, Simone; Piran, Tsvi; Shaviv, Nir
  • Monthly Notices of the Royal Astronomical Society, Vol. 438, Issue 2
  • DOI: 10.1093/mnras/stt2188

Particle acceleration in explosive relativistic reconnection events and Crab Nebula gamma-ray flares
journal, April 2018

  • Lyutikov, Maxim; Komissarov, Serguei; Sironi, Lorenzo
  • Journal of Plasma Physics, Vol. 84, Issue 2
  • DOI: 10.1017/S0022377818000168

Did Swift measure gamma-ray burst prompt emission radii?
journal, June 2006


Spectrum and Light Curve of a Supernova Shock Breakout Through a Thick Wolf-Rayet wind
journal, May 2014


Early GRB Afterglows from Reverse Shocks in Ultra-relativistic, Long-lasting Winds
journal, January 2017


Rapidly Evolving and Luminous Transients from Pan-Starrs1
journal, September 2014


Mass transfer between double white dwarfs
journal, May 2004


The physics of gamma-ray bursts
journal, January 2005


Common envelope evolution and double cores of planetary nebulae
journal, July 1990


X-ray Swift observations of SN 2018cow
journal, August 2018

  • Rivera Sandoval, L. E.; Maccarone, T. J.; Corsi, A.
  • Monthly Notices of the Royal Astronomical Society: Letters, Vol. 480, Issue 1
  • DOI: 10.1093/mnrasl/sly145

Probing type Ia supernova properties using bolometric light curves from the Carnegie Supernova Project and the CfA Supernova Group
journal, November 2018

  • Scalzo, R. A.; Parent, E.; Burns, C.
  • Monthly Notices of the Royal Astronomical Society, Vol. 483, Issue 1
  • DOI: 10.1093/mnras/sty3178