FRB Theory Wiki - User contributions [en]

Wandering Pulsar

2018-10-11T15:58:53Z

Sulona: /* Model Description */

{{FRBTableTemplate
|Category = Other
|Progenitor = Wandering Pulsar Beams
|Type = Repeat
|EnergyMechanism = --
|EmissionMechanism = --
|LFRadioCounterpart = Yes
|HFRadioCounterpart = --
|MicrowaveCounterpart = --
|THzCounterpart = --
|OIRCounterpart = --
|XrayCounterpart = --
|GammarayCounterpart = --
|GWCounterpart = --
|NeutrinoCounterpart = --
|References = http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1611.01243
|Comments = Any counterparts will be associated with the pulsar, but are not specified.
}}

== Model Description ==

This model assumes the presence of a steady beam of pulsar emission whose direction randomly changes. If this beam sweeps across the line of sight of an observer, it may be observable as an FRB. The duration of the FRB depends on the speed at which the beam moves across the sky, and hence a wandering beam mitigates the enormous power and high spin-down requirements of giant pulse and flare models.

== Observational Constraints ==

This scenario can also consistently explain two pairs of possibly distinct radio bursts detected in FRB 121102. Details about an emission mechanism or possible counterparts are not given.

Wandering Pulsar

2018-10-11T15:58:21Z

Sulona: /* Model Description */

{{FRBTableTemplate
|Category = Other
|Progenitor = Wandering Pulsar Beams
|Type = Repeat
|EnergyMechanism = --
|EmissionMechanism = --
|LFRadioCounterpart = Yes
|HFRadioCounterpart = --
|MicrowaveCounterpart = --
|THzCounterpart = --
|OIRCounterpart = --
|XrayCounterpart = --
|GammarayCounterpart = --
|GWCounterpart = --
|NeutrinoCounterpart = --
|References = http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1611.01243
|Comments = Any counterparts will be associated with the pulsar, but are not specified.
}}

== Model Description ==

This model assumes the presence of a steady beam of pulsar emission whose directlion randomly changes. If this beam sweeps across the line of sight of an observer, it may be observable as an FRB. The duration of the FRB depends on the speed at which the beam moves across the sky, and hence a wandering beam mitigates the enormous power and high spin-down requirements of giant pulse and flare models.

== Observational Constraints ==

This scenario can also consistently explain two pairs of possibly distinct radio bursts detected in FRB 121102. Details about an emission mechanism or possible counterparts are not given.

Superconducting Cosmic Strings

2018-10-11T11:30:04Z

Sulona: /* Observational Constraints */

{{FRBTableTemplate
|Category = Other
|Progenitor = Superconducting Cosmic Strings
|Type = Single
|EnergyMechanism = Cusp decay
|EmissionMechanism = --
|LFRadioCounterpart = Yes
|HFRadioCounterpart = --
|MicrowaveCounterpart = --
|THzCounterpart = --
|OIRCounterpart = --
|XrayCounterpart = --
|GammarayCounterpart = GRB <br/> if jet aligned
|GWCounterpart = Yes
|NeutrinoCounterpart = Yes
|References = http://adsabs.harvard.edu/abs/2015AASP....5...43Z, http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1807.01976, http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:0802.0711

|Comments = High energy cosmic rays are also expected.
}}

== Model Description ==

A cosmic string becomes superconducting when coupled with electromagnetism; achievable through the unbroken symmetry of an extra Higgs field in the formation of the string. Various mechanisms have been considered in which superconducting cosmic strings may produce an FRB, such as: string oscillations, the collisions of string structures (cusps and kinks), and the interaction of a current-carrying loop in the magnetic field of a galaxy. In the last scenario listed, the event rate of FRBs indicates a loop size consistent with strings formed during the radiation era. The emission from superconducting cosmic strings is linearly polarized - an intrinsic signature that is independent of frequency and is not affected by polarization via the ISM. Expected counterparts are other EM counterparts - specifically, GRBs, cosmic rays, and neutrinos - and GWs.

== Observational Constraints ==

-

Wandering Beam

2018-10-11T11:25:21Z

Sulona: /* Observational Constraints */

{{FRBTableTemplate
|Category = AGN
|Progenitor = Wandering Beam
|Type = Repeat
|EnergyMechanism = --
|EmissionMechanism = Synch.
|LFRadioCounterpart = Yes
|HFRadioCounterpart = --
|MicrowaveCounterpart = --
|THzCounterpart = --
|OIRCounterpart = --
|XrayCounterpart = Yes
|GammarayCounterpart = --
|GWCounterpart = --
|NeutrinoCounterpart = --
|References = http://adsabs.harvard.edu/abs/2017MNRAS.471L..92K
|Comments = None
}}

== Model Description ==
FRBs may be formed by a scaled down version of an AGN . The jet formation and beaming mechanism is as in the AGN scenario, but the BH under consideration has a mass lower than the supermassive BHs of AGNs. If the moderately sized BH is set in a turbulent medium, such as a giant molecular cloud in a starburst galaxy, the angular momentum axis of the BH may be large, and the narrowly collimated beams will randomly change directions. When a beam sweeps across an observers line of sight, it may be observable as an FRB. There will be a persistent variable radio signal as in an AGN, and very soft X-ray/extreme UV emission from the accretion disk of the BH. The latter would be strongly absorbed in the Galactic plane, and thus only observable for FRBs at high Galactic latitudes.

== Observational Constraints ==
-

White Holes

2018-10-11T11:23:42Z

Sulona: /* Observational Constraints */

{{FRBTableTemplate
|Category = Other
|Progenitor = White Holes
|Type = Single
|EnergyMechanism = --
|EmissionMechanism = --
|LFRadioCounterpart = Yes
|HFRadioCounterpart = --
|MicrowaveCounterpart = --
|THzCounterpart = --
|OIRCounterpart = Yes
|XrayCounterpart = --
|GammarayCounterpart = Yes
|GWCounterpart = --
|NeutrinoCounterpart = --
|References = http://adsabs.harvard.edu/abs/2014PhRvD..90l7503B, http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1611.01243
|Comments = None
}}

== Model Description ==

Should a collapsing star reach the Planck density, becoming a Planck star, it will cease to collapse further and will explode outwards (or bounce) to form a white hole (WH). Due to their age, PBHs or Planck stars are the strongest candidates to form WHs which may be observable today, and the energy they release is consistent with FRBs. A single FRB is expected, accompanied by an IR signal - with a wave length on the order of the exploding star -, as well as Gamma-rays, characterized by the material expelled in the explosion .

== Observational Constraints ==
-

NS Combing

2018-10-11T11:07:57Z

Sulona: /* Observational Constraints */

{{FRBTableTemplate
|Category = Other
|Progenitor = NS Combing
|Type = Both
|EnergyMechanism = Various
|EmissionMechanism = Mag. reconnection
|LFRadioCounterpart = Yes
|HFRadioCounterpart = --
|MicrowaveCounterpart = --
|THzCounterpart = --
|OIRCounterpart = --
|XrayCounterpart = --
|GammarayCounterpart = --
|GWCounterpart = --
|NeutrinoCounterpart = --
|References = http://adsabs.harvard.edu/abs/2017ApJ...836L..32Z, http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1801.05436
|Comments = The model can apply to a variety of events, and thus counterparts will depend on the scenario.
}}

== Model Description ==

Cosmic combing is the process in which the field lines of a NS's magnetosphere are swept out in a stream by a strong plasma. The effect is caused by ram pressure: the bulk resistance of a fluid acting on an object. When this pressure is greater than the magnetic field pressure, the drag will comb the magnetic field in a different direction, causing reconnection with emission consistent with an FRB . Combing may occur in a variety of situations, such as: a GRB, a SN, an AGN flare, or a stellar flare. As such, it is a difficult theory to test in general, however a specific scenario has been considered: the combing of a pulsar by an accreting SMBH. An FRB would be observable for half of the pulsar's orbital period around the SMBH, implying the signal is periodic. This periodicity would not be perfect - the SMBH wind that initiates FRBs is variable and thus FRB signals are sporadic. The RM should vary with orbital periodicity, but this would be more difficult to confirm given the sporadic FRB emission. Finally, the polarization angle of each burst within an orbital period would vary depending on the phase of the pulsar's orbit, and should be correlated with the varying RM.

== Observational Constraints ==

N/A

NS Combing

2018-10-11T11:04:22Z

Sulona: /* Model Description */

NS-NS Merger (Mag. Braking)

2018-10-11T10:57:11Z

Sulona: /* Model Description */

{{FRBTableTemplate
|Category = Merger
|Progenitor = NS-NS
|Type = Single
|EnergyMechanism = Mag. braking
|EmissionMechanism = --
|LFRadioCounterpart = Yes
|HFRadioCounterpart = Yes
|MicrowaveCounterpart = --
|THzCounterpart = --
|OIRCounterpart = Kilonova
|XrayCounterpart = Afterglow
|GammarayCounterpart = sGRB <br/> if jet aligned
|GWCounterpart = Yes
|NeutrinoCounterpart = --
|References = http://adsabs.harvard.edu/abs/2013PASJ...65L..12T
|Comments =
}}

== Model Description ==

Consider the merging of two differentially rotating NSs into a uniformly rotating hypermassive NS. Upon coalescence, the merger spins down and magnetic braking generates coherent radiation. Since the merger rate of NSs is consistent with the expected FRB rate, this model implies that a large fraction of NS mergers must produce FRBs. Significant mass ejections are likely to occur during the merger process, which render FRBs unable to penetrate the ejecta. There is a 1 ms time frame after the maximum rotation speed of the merger is reached and before the release of dynamical ejecta, during which the transmission of a single FRB is possible.

== Observational Constraints ==

Stellar Coronae

2018-10-11T10:36:43Z

Sulona: /* Model Description */

{{FRBTableTemplate
|Category = Void
|Progenitor = Stellar Corona
|Type = Both
|EnergyMechanism = N/A
|EmissionMechanism = N/A
|LFRadioCounterpart = N/A
|HFRadioCounterpart = N/A
|MicrowaveCounterpart = N/A
|THzCounterpart = N/A
|OIRCounterpart = N/A
|XrayCounterpart = N/A
|GammarayCounterpart = N/A
|GWCounterpart = N/A
|NeutrinoCounterpart = N/A
|References = http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1310.2419, http://adsabs.harvard.edu/abs/2015MNRAS.454.2183M
|Comments = None
}}

== Model Description ==

One of the last surviving theories for FRBs of Galactic origins was flare stars. The theory was seemed fitting because dwarf stars have been observed to produce bursts of coherent radiation on short timescales ($< 5$ ms) and have been observed within FRB fields. A cyclotron maser in the lower part of the stellar corona could produce a flare consistent with FRB observations; the large DM and pulse smearing could be attributed to the corona plasma. Free-free absorption that occurs in the corona, however, presents a problem: a radio signal from the lower corona with the required DM may be unobservable unless the corona is infeasibly extended or hot. Further, the plasma density required for the DM is arguably too high to produce the frequency dependence on the pulse arrival times observed for FRBs. In defence of the theory, observations by are given that show high flare temperatures capable of mitigating significant free-free absorption. Further, if frequency drifts occur in flares (as observed in), the measured dispersion relationship for FRBs may be possible. Doubt is then cast on the theory again when it is shown that the brightness temperature of FRBs could not escape plasma as dense as the DM demands.

== Observational Constraints ==

N/A

Superconducting Cosmic Strings

2018-10-11T10:22:52Z

Sulona: /* Model Description */

Tiny EM Explosions

2018-10-11T10:15:38Z

Sulona: /* Model Description */

{{FRBTableTemplate
|Category = Other
|Progenitor = Tiny EM Explosions
|Type = Both
|EnergyMechanism = Thin shell interactions
|EmissionMechanism = Curv.
|LFRadioCounterpart = Yes
|HFRadioCounterpart = Yes
|MicrowaveCounterpart = --
|THzCounterpart = --
|OIRCounterpart = --
|XrayCounterpart = --
|GammarayCounterpart = Unlikely observable
|GWCounterpart = --
|NeutrinoCounterpart = --
|References = http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1703.00393, http://adsabs.harvard.edu/abs/2017ApJ...844...65T
|Comments = None
}}

== Model Description ==

The collision of two relativistic macroscopic dipoles that form around the time of cosmic electroweak symmetry-breaking could cause a tiny explosion. Tiny electromagnetic explosions occur when the initial wavelength of the explosion is narrower than the wavelength of the radiation observed so the energy travels outwards in a very thin shell, and the surrounding charged particles are deflected (as opposed to reflected) by the magnetic field embedded in the expanding shell.

To retain the supporting electric field for cosmological timescales, these field structures must be superconducting, and are thus dubbed large superconducting dipoles (LSD) - the term "Large" is relative, and is used because the dipoles are macroscopic. The expanding relativistic magnetized shell from the explosion couples efficiently to a low-frequency, strong, superluminal EM wave in the surrounding plasma, allowing the emission to escape. Three emission mechanisms are possible: the reflection of an ambient static magnetic field by the conducting surface of the shell; direct linear conversion of the magnetic field in the shell; and the excitation of an EM wave if the surface of the shell becomes corrugated via the reconnection of the ejected magnetic field with the ambient magnetic field. The deceleration of the magnetic shell causes a higher frequency radio pulse and the thermal part of the explosion radiates Gamma-rays, however the latter are not expected to be detectable. The model accounts for repeating and non-repeating FRBs and for their observed differences in linear polarizations and RMs - the hydromagnetic drag on LSDs is weak in the ISM, and strong in high - density environments. As such, a slowly accreting SMBH may capture LSDs and group them in gravitationally bound cusps, within which the LSDs collide and create repeating FRBs. Here the high density plasma accounts for the high linear polarization and high RM observed in FRB 121102. The opposite is true for LSDs far from the SMBH; where the observed RM is low and signals are non-repeating, such as in FRB 150215, collisions are expected to take place in dark matter halos of galaxies.

== Observational Constraints ==

To be filled in with updated draft

Tiny EM Explosions

2018-10-11T10:15:11Z

Sulona: /* Model Description */

{{FRBTableTemplate
|Category = Other
|Progenitor = Tiny EM Explosions
|Type = Both
|EnergyMechanism = Thin shell interactions
|EmissionMechanism = Curv.
|LFRadioCounterpart = Yes
|HFRadioCounterpart = Yes
|MicrowaveCounterpart = --
|THzCounterpart = --
|OIRCounterpart = --
|XrayCounterpart = --
|GammarayCounterpart = Unlikely observable
|GWCounterpart = --
|NeutrinoCounterpart = --
|References = http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1703.00393, http://adsabs.harvard.edu/abs/2017ApJ...844...65T
|Comments = None
}}

== Model Description ==

The collision of two relativistic macroscopic dipoles that form around the time of cosmic electroweak symmetry-breaking could cause a tiny explosion. Tiny electromagnetic explosions occur when the initial wavelength of the explosion is narrower than the wavelength of the radiation observed so the energy travels outwards in a very thin shell, and the surrounding charged particles are deflected (as opposed to reflected) by the magnetic field embedded in the expanding shell.

To retain the supporting electric field for cosmological timescales, these field structures must be superconducting, and are thus dubbed large superconducting dipoles (LSD) - the term "Large" is relative, and is used because the dipoles are macroscopic. The expanding relativistic magnetized shell from the explosion couples efficiently to a low-frequency, strong, superluminal EM wave in the surrounding plasma, allowing the emission to escape. Three emission mechanisms are possible: the reflection of an ambient static magnetic field by the conducting surface of the shell; direct linear conversion of the magnetic field in the shell; and the excitation of an EM wave if the surface of the shell becomes corrugated via the reconnection of the ejected magnetic field with the ambient magnetic field. The deceleration of the magnetic shell causes a higher frequency radio pulse and the thermal part of the explosion radiates \gamma-rays, however the latter are not expected to be detectable. The model accounts for repeating and non-repeating FRBs and for their observed differences in linear polarizations and RMs - the hydromagnetic drag on LSDs is weak in the ISM, and strong in high - density environments. As such, a slowly accreting SMBH may capture LSDs and group them in gravitationally bound cusps, within which the LSDs collide and create repeating FRBs. Here the high density plasma accounts for the high linear polarization and high RM observed in FRB 121102. The opposite is true for LSDs far from the SMBH; where the observed RM is low and signals are non-repeating, such as in FRB 150215, collisions are expected to take place in dark matter halos of galaxies.

== Observational Constraints ==

To be filled in with updated draft

Tiny EM Explosions

2018-10-11T10:14:42Z

Sulona: /* Model Description */

{{FRBTableTemplate
|Category = Other
|Progenitor = Tiny EM Explosions
|Type = Both
|EnergyMechanism = Thin shell interactions
|EmissionMechanism = Curv.
|LFRadioCounterpart = Yes
|HFRadioCounterpart = Yes
|MicrowaveCounterpart = --
|THzCounterpart = --
|OIRCounterpart = --
|XrayCounterpart = --
|GammarayCounterpart = Unlikely observable
|GWCounterpart = --
|NeutrinoCounterpart = --
|References = http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1703.00393, http://adsabs.harvard.edu/abs/2017ApJ...844...65T
|Comments = None
}}

== Model Description ==

The collision of two relativistic macroscopic dipoles that form around the time of cosmic electroweak symmetry-breaking could cause a tiny explosion. Tiny electromagnetic explosions occur when the initial wavelength of the explosion is narrower than the wavelength of the radiation observed so the energy travels outwards in a very thin shell, and the surrounding charged particles are deflected (as opposed to reflected) by the magnetic field embedded in the expanding shell.

To retain the supporting electric field for cosmological timescales, these field structures must be superconducting, and are thus dubbed large superconducting dipoles (LSD) - the term "Large" is relative, and is used because the dipoles are macroscopic. The expanding relativistic magnetized shell from the explosion couples efficiently to a low-frequency, strong, superluminal EM wave in the surrounding plasma, allowing the emission to escape. Three emission mechanisms are possible: the reflection of an ambient static magnetic field by the conducting surface of the shell; direct linear conversion of the magnetic field in the shell; and the excitation of an EM wave if the surface of the shell becomes corrugated via the reconnection of the ejected magnetic field with the ambient magnetic field. The deceleration of the magnetic shell causes a higher frequency radio pulse and the thermal part of the explosion radiates $\gamma$-rays, however the latter are not expected to be detectable. The model accounts for repeating and non-repeating FRBs and for their observed differences in linear polarizations and RMs - the hydromagnetic drag on LSDs is weak in the ISM, and strong in high - density environments. As such, a slowly accreting SMBH may capture LSDs and group them in gravitationally bound cusps, within which the LSDs collide and create repeating FRBs. Here the high density plasma accounts for the high linear polarization and high RM observed in FRB 121102. The opposite is true for LSDs far from the SMBH; where the observed RM is low and signals are non-repeating, such as in FRB 150215, collisions are expected to take place in dark matter halos of galaxies.

== Observational Constraints ==

To be filled in with updated draft

Tiny EM Explosions

2018-10-11T10:14:01Z

Sulona: /* Model Description */

{{FRBTableTemplate
|Category = Other
|Progenitor = Tiny EM Explosions
|Type = Both
|EnergyMechanism = Thin shell interactions
|EmissionMechanism = Curv.
|LFRadioCounterpart = Yes
|HFRadioCounterpart = Yes
|MicrowaveCounterpart = --
|THzCounterpart = --
|OIRCounterpart = --
|XrayCounterpart = --
|GammarayCounterpart = Unlikely observable
|GWCounterpart = --
|NeutrinoCounterpart = --
|References = http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1703.00393, http://adsabs.harvard.edu/abs/2017ApJ...844...65T
|Comments = None
}}

== Model Description ==

The collision of two relativistic macroscopic dipoles that form around the time of cosmic electroweak symmetry-breaking could cause a tiny explosion. Tiny electromagnetic explosions occur when the initial wavelength of the explosion is narrower than the wavelength of the radiation observed so the energy travels outwards in a very thin shell, and the surrounding charged particles are deflected (as opposed to reflected) by the magnetic field embedded in the expanding shell.

To retain the supporting electric field for cosmological timescales, these field structures must be superconducting, and are thus dubbed large superconducting dipoles (LSD) - the term ``Large'' is relative, and is used because the dipoles are macroscopic. The expanding relativistic magnetized shell from the explosion couples efficiently to a low-frequency, strong, superluminal EM wave in the surrounding plasma, allowing the emission to escape. Three emission mechanisms are possible: the reflection of an ambient static magnetic field by the conducting surface of the shell; direct linear conversion of the magnetic field in the shell; and the excitation of an EM wave if the surface of the shell becomes corrugated via the reconnection of the ejected magnetic field with the ambient magnetic field. The deceleration of the magnetic shell causes a higher frequency radio pulse and the thermal part of the explosion radiates $\gamma$-rays, however the latter are not expected to be detectable. The model accounts for repeating and non-repeating FRBs and for their observed differences in linear polarizations and RMs - the hydromagnetic drag on LSDs is weak in the ISM, and strong in high - density environments. As such, a slowly accreting SMBH may capture LSDs and group them in gravitationally bound cusps, within which the LSDs collide and create repeating FRBs. Here the high density plasma accounts for the high linear polarization and high RM observed in FRB 121102. The opposite is true for LSDs far from the SMBH; where the observed RM is low and signals are non-repeating, such as in FRB 150215, collisions are expected to take place in dark matter halos of galaxies.

== Observational Constraints ==

To be filled in with updated draft

Variable Stars

2018-10-11T10:04:19Z

Sulona: /* Observational Constraints */

{{FRBTableTemplate
|Category = Other
|Progenitor = Variable Stars
|Type = Repeat
|EnergyMechanism = Undulator
|EmissionMechanism = Synch.
|LFRadioCounterpart = Yes
|HFRadioCounterpart = --
|MicrowaveCounterpart = --
|THzCounterpart = --
|OIRCounterpart = --
|XrayCounterpart = --
|GammarayCounterpart = --
|GWCounterpart = --
|NeutrinoCounterpart = --
|References = http://adsabs.harvard.edu/abs/2018MNRAS.477.2470L
|Comments = None
}}

== Model Description ==

Variable stars may be a source of FRBs, where synchrotron emission is generated by an astrophysical undulator. The model assumes the existence of a weak, axial-symmetric magnetic field some distance from a variable star. The emission frequency will vary relative to the observer, due to the change in opening angles between the observer and direction of emission as the star rotates. Multiple peaks are possible in this scenario. For this model to hold, one must observe a positive frequency sweep ahead of a negative frequency sweep.

== Observational Constraints ==

Multiple peaks are possible. For this model to hold, one must observe a positive frequency sweep ahead of a negative frequency sweep. Predicted DM's are consistent with observations.

Variable Stars

2018-10-11T10:03:30Z

Sulona: /* Model Description */

Wandering Beam

2018-10-11T10:00:29Z

Sulona: /* Model Description */

WD-BH Merger

2018-10-11T09:57:39Z

Sulona: /* Observational Constraints */

{{FRBTableTemplate
|Category = Merger
|Progenitor = WD-BH
|Type = Single
|EnergyMechanism = Maser
|EmissionMechanism = Synch.
|LFRadioCounterpart = --
|HFRadioCounterpart = --
|MicrowaveCounterpart = --
|THzCounterpart = --
|OIRCounterpart = --
|XrayCounterpart = Yes (transient accretion disk)
|GammarayCounterpart = --
|GWCounterpart = --
|NeutrinoCounterpart = --
|References = http://adsabs.harvard.edu/abs/2018RAA....18...61L
|Comments = None
}}

== Model Description ==

During the merger of a BH and a WD, a transient accretion disk is expected to form around the BH, which could power a high speed wind around the entire BH-accretion disk system, forming a corona. Closed magnetic field lines, emerging continuously between the accretion disk and the corona, are twisted by the turbulence in the system, leading to the formation of rope-like flux structures in the corona. When the threshold for mass equilibrium is exceeded, the rope is thrust outward as an episodic jet of relativistic magnetized plasma; a so-called "magnetic blob". Before the accretion disk is exhausted, 2 - 3 magnetic blobs could be ejected at different speeds and will collide at a time after ejection. The collision causes catastrophic magnetic reconnection, and the release of magnetic energy is propagated through the magnetized cold plasma of the blob, and converted to particle kinetic energy. The resulting synchrotron maser could power a non-repeating FRB. Note that the accretion disk is advection-dominated. If the disk has a neutron-dominated accretion flow, only a single blob can be ejected within the lifetime of the accretion disk, and thus no collision will take place. X-ray emission from the accretion disk is expected, which will last only as long as the transient disk itself.

== Observational Constraints ==

The expected duration, frequency and energetics in this scenario are consistent with FRBs, and the event rate of BH-WD mergers is compatible with that expected for non-repeating FRBs.

WD-BH Merger

2018-10-11T09:57:21Z

Sulona: /* Model Description */

WD-BH Merger

2018-10-11T09:53:18Z

Sulona: /* Model Description */

{{FRBTableTemplate
|Category = Merger
|Progenitor = WD-BH
|Type = Single
|EnergyMechanism = Maser
|EmissionMechanism = Synch.
|LFRadioCounterpart = --
|HFRadioCounterpart = --
|MicrowaveCounterpart = --
|THzCounterpart = --
|OIRCounterpart = --
|XrayCounterpart = Yes (transient accretion disk)
|GammarayCounterpart = --
|GWCounterpart = --
|NeutrinoCounterpart = --
|References = http://adsabs.harvard.edu/abs/2018RAA....18...61L
|Comments = None
}}

== Model Description ==

During the merger of a BH and a WD, a transient accretion disk is expected to form around the BH, which could power a high speed wind around the entire BH-accretion disk system, forming a corona. Closed magnetic field lines, emerging continuously between the accretion disk and the corona, are twisted by the turbulence in the system, leading to the formation of rope-like flux structures in the corona. When the threshold for mass equilibrium is exceeded, the rope is thrust outward as an episodic jet of relativistic magnetized plasma; a so-called "magnetic blob". Before the accretion disk is exhausted, 2 - 3 magnetic blobs could be ejected at different speeds and will collide at a time after ejection. The collision causes catastrophic magnetic reconnection, and the release of magnetic energy is propagated through the magnetized cold plasma of the blob, and converted to particle kinetic energy. The resulting synchrotron maser could power a non-repeating FRB. The expected duration, frequency and energetics in this scenario are consistent with FRBs, and the event rate of BH-WD mergers is compatible with that expected for non-repeating FRBs. Note that the accretion disk is advection-dominated. If the disk has a neutron-dominated accretion flow, only a single blob can be ejected within the lifetime of the accretion disk, and thus no collision will take place. X-ray emission from the accretion disk is expected, which will last only as long as the transient disk itself.

== Observational Constraints ==

--

WD-BH Merger

2018-10-11T09:51:44Z

Sulona: /* Model Description */

{{FRBTableTemplate
|Category = Merger
|Progenitor = WD-BH
|Type = Single
|EnergyMechanism = Maser
|EmissionMechanism = Synch.
|LFRadioCounterpart = --
|HFRadioCounterpart = --
|MicrowaveCounterpart = --
|THzCounterpart = --
|OIRCounterpart = --
|XrayCounterpart = Yes (transient accretion disk)
|GammarayCounterpart = --
|GWCounterpart = --
|NeutrinoCounterpart = --
|References = http://adsabs.harvard.edu/abs/2018RAA....18...61L
|Comments = None
}}

== Model Description ==

During the merger of a BH and a WD, a transient accretion disk is expected to form around the BH, which could power a high speed wind around the entire BH-accretion disk system, forming a corona. Closed magnetic field lines, emerging continuously between the accretion disk and the corona, are twisted by the turbulence in the system, leading to the formation of rope-like flux structures in the corona. When the threshold for mass equilibrium is exceeded, the rope is thrust outward as an episodic jet of relativistic magnetized plasma; a so-called ``magnetic blob''. Before the accretion disk is exhausted, 2\textendash3 magnetic blobs could be ejected at different speeds and will collide at a time after ejection. The collision causes catastrophic magnetic reconnection, and the release of magnetic energy is propagated through the magnetized cold plasma of the blob, and converted to particle kinetic energy. The resulting synchrotron maser could power a non-repeating FRB. The expected duration, frequency and energetics in this scenario are consistent with FRBs, and the event rate of BH-WD mergers is compatible with that expected for non-repeating FRBs. Note that the accretion disk is advection-dominated. If the disk has a neutron-dominated accretion flow, only a single blob can be ejected within the lifetime of the accretion disk, and thus no collision will take place. X-ray emission from the accretion disk is expected, which will last only as long as the transient disk itself.

== Observational Constraints ==

--

White Holes

2018-10-11T09:41:57Z

Sulona: /* Model Description */

{{FRBTableTemplate
|Category = Other
|Progenitor = White Holes
|Type = Single
|EnergyMechanism = --
|EmissionMechanism = --
|LFRadioCounterpart = Yes
|HFRadioCounterpart = --
|MicrowaveCounterpart = --
|THzCounterpart = --
|OIRCounterpart = Yes
|XrayCounterpart = --
|GammarayCounterpart = Yes
|GWCounterpart = --
|NeutrinoCounterpart = --
|References = http://adsabs.harvard.edu/abs/2014PhRvD..90l7503B, https://arxiv.org/pdf/1801.03841.pdf
|Comments = None
}}

== Model Description ==

Should a collapsing star reach the Planck density, becoming a Planck star, it will cease to collapse further and will explode outwards (or bounce) to form a white hole (WH). Due to their age, PBHs or Planck stars are the strongest candidates to form WHs which may be observable today, and the energy they release is consistent with FRBs. A single FRB is expected, accompanied by an IR signal - with a wave length on the order of the exploding star -, as well as Gamma-rays, characterized by the material expelled in the explosion .

== Observational Constraints ==

To be filled in with updated draft

White Holes

2018-10-11T09:39:42Z

Sulona: /* Model Description */

{{FRBTableTemplate
|Category = Other
|Progenitor = White Holes
|Type = Single
|EnergyMechanism = --
|EmissionMechanism = --
|LFRadioCounterpart = Yes
|HFRadioCounterpart = --
|MicrowaveCounterpart = --
|THzCounterpart = --
|OIRCounterpart = Yes
|XrayCounterpart = --
|GammarayCounterpart = Yes
|GWCounterpart = --
|NeutrinoCounterpart = --
|References = http://adsabs.harvard.edu/abs/2014PhRvD..90l7503B, https://arxiv.org/pdf/1801.03841.pdf
|Comments = None
}}

== Model Description ==

Should a collapsing star reach the Planck density---to become a Planck star---it will cease to collapse further and will explode outwards (or bounce) to form a white hole (WH). Due to their age, PBHs or Planck stars are the strongest candidates to form WHs which may be observable today, and the energy they release is consistent with FRBs. A single FRB is expected, accompanied by an IR signal with a wave length on the order of the exploding star and Gamma-rays characterized by the material expelled in the explosion .

== Observational Constraints ==

To be filled in with updated draft