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

@article{Margutti2019AnEX,
  title={An Embedded X-Ray Source Shines through the Aspherical AT 2018cow: Revealing the Inner Workings of the Most Luminous Fast-evolving Optical Transients},
  author={R. Margutti and Brian D. Metzger and Ryan Chornock and Indrek Vurm and Nathaniel Roth and Brian W. Grefenstette and V. Savchenko and R'egis Cartier and James F. Steiner and Giacomo Terreran and Ben Margalit and Giulia Migliori and Dan Milisavljevic and Kate D. Alexander and Michael F. Bietenholz and Peter K. Blanchard and Enrico Bozzo and Daniel K. Brethauer and Igor V. Chilingarian and Deanne L. Coppejans and Lorenzo Ducci and Carlo Ferrigno and Wen-fai Fong and Diego G{\"o}tz and C. Guidorzi and Aprajita Hajela and Kevin Hurley and Erik Kuulkers and Philippe Laurent and Sandro Mereghetti and Matt Nicholl and Daniel J. Patnaude and Pietro Ubertini and J M Banovetz and Norbert Bartel and Edo Berger and Eric R. Coughlin and Tarraneh Eftekhari and Dmitry D. Frederiks and Anna V. Kozlova and Tanmoy Laskar and Dmitry S. Svinkin and Maria R. Drout and Andrew MacFadyen and Kerry Paterson},
  journal={The Astrophysical Journal},
  year={2019}
}
We present the first extensive radio to γ-ray observations of a fast-rising blue optical transient, AT 2018cow, over its first ~100 days. AT 2018cow rose over a few days to a peak luminosity L_(pk) ~ 4 × 10^(44) erg s^(−1), exceeding that of superluminous supernovae (SNe), before declining as L ∝ t^(−2). Initial spectra at δt ≾ 15 days were mostly featureless and indicated large expansion velocities v ~ 0.1c and temperatures reaching T ~ 3 × 10^4 K. Later spectra revealed a persistent optically… 
AT 2018cow VLBI: no long-lived relativistic outflow
Abstract We report on VLBI observations of the fast and blue optical transient (FBOT), AT 2018cow. At ∼62 Mpc, AT 2018cow is the first relatively nearby FBOT. The nature of AT 2018cow is not clear,
uGMRT Observations of a Fast and Blue Optical Transient—AT 2018cow
We present low-fRequency radio observations of a fast-rising blue optical transient (FBOT), AT 2018cow, with the upgraded Giant Metrewave Radio Telescope (uGMRT). Our observations span t = 11–570
The fast, luminous ultraviolet transient AT2018cow: extreme supernova, or disruption of a star by an intermediate-mass black hole?
Wide-field optical surveys have begun to uncover large samples of fast (t_rise 10 days. The spectrum remains extremely hot throughout its evolution, and the photospheric radius contracts with time
The Nearby Luminous Transient AT2018cow: A Magnetar Formed in a Subrelativistically Expanding Nonjetted Explosion
The fast-rising blue optical transient AT2018cow indicated unusual early-phase characteristics unlike relatively better studied explosive transients. Its afterglow may be produced by either a
The Exotic Type Ic Broad-lined Supernova SN 2018gep: Blurring the Line between Supernovae and Fast Optical Transients
In the last decade a number of rapidly evolving transients have been discovered that are not easily explained by traditional supernova models. We present optical and UV data on one such object, SN
Signatures of circumstellar interaction in the unusual transient AT 2018cow
  • O. Fox, N. Smith
  • Physics
    Monthly Notices of the Royal Astronomical Society
  • 2019
AT 2018cow is a unique transient that stands out due to its relatively fast light curve, high peak bolometric luminosity, and blue colour. These properties distinguish it from typical radioactively
Late-time Radio and Millimeter Observations of Superluminous Supernovae and Long Gamma-Ray Bursts: Implications for Central Engines, Fast Radio Bursts, and Obscured Star Formation
We present the largest and deepest late-time radio and millimeter survey to date of superluminous supernovae (SLSNe) and long-duration gamma-ray bursts (LGRBs) to search for associated nonthermal
AT2018cow: A Luminous Millimeter Transient
We present detailed submillimeter- through centimeter-wave observations of the extraordinary extragalactic transient AT2018cow. The apparent characteristics -- the high radio luminosity, the
H i 21 cm mapping of the host galaxy of AT2018cow: a fast-evolving luminous transient within a ring of high column density gas
We report Giant Metrewave Radio Telescope H i 21 cm imaging of CGCG 137–068, the host galaxy of the fast-evolving luminous transient (FELT) AT2018cow. This is the first study of the gas properties of
STROBE-X: X-ray Timing and Spectroscopy on Dynamical Timescales from Microseconds to Years
We present the Spectroscopic Time-Resolving Observatory for Broadband Energy X-rays (STROBE-X), a probe-class mission concept selected for study by NASA. It combines huge collecting area, high
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