Compton Scattering of Magnetohydrodynamic and Plasma Waves as a Source of Radio Emission from Metagalactic Objects

AbstractInverse Compton Scattering (ICS) is a very important process not only in inner gap physics, but also for radio emission. ICS of high energy particles with thermal photons is the dominant and a very efficient mechanism of the particle energy loss above the neutron star surface, and is an important process in causing gap breakdown. The pulsar distribution in theP−Pdiagram and the observed mode changing phenomenon of some pulsars can be expained by the sparking conditions due to ICS. ICS of the secondary particles with the low frequency wave from the inner gap sparking can be responsible for radio emission. In this ICS model, many observational features of pulsar radio emission can be explained, such as: one core and two conal emission components, their different emission altitudes and relative time delay effects; spectral behavior of pulse profiles; the behavior of the linear polarization and position angle.

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ExPRES Modeling of Auroral Radio Source Occultation observed by Galileo Application to JUICE and Juno

10.5194/epsc2020-962 ◽

2020 ◽

Author(s):

Baptiste Cecconi ◽

Corentin K Louis ◽

Claudio Munoz ◽

Claire Vallat

Keyword(s):

Radio Emission ◽

Radio Source ◽

Plasma Waves ◽

Physical Parameters ◽

Operation Planning ◽

Radio Emissions ◽

Galilean Moons ◽

Temporal Occurrence ◽

Galilean Moon ◽

Ionospheric Sounding

<p>The ExPRES code simulates exoplanetary and planetary auroral radio emissions. It could be used to predict and interpret Jupiter&#8217;s radio emissions in the hectometric and decametric range. In this study, we model the occultations of the Jovian auroral radio emissions during the Galilean moons flybys by the Galileo spacecraft. In this study, we focus on auroral radio emissions, configuring the ExPRES simulations runs with typical radio source physical parameters. We compare the simulations run results with the actual Galileo/PWS observations, and show that we accurately model the temporal occurrence of the occultations in the whole spectral range observed by Galileo. We can then predict auroral radio emission occultations by the Galilean moons for the Juno and JUICE missions. ExPRES will be used by the JUICE/RPWI (Radio Plasma Waves Investigation) team to prepare its operation planning during the Galilean moon flybys for, e.g., the Galilean moon ionosphere characterization science objective, with passive ionospheric sounding during ingress and egress of Jovian radio source occultations.&#160;</p>

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The X‐Ray and Radio Emission from SN 2002ap: The Importance of Compton Scattering

The Astrophysical Journal ◽

10.1086/382584 ◽

2004 ◽

Vol 605 (2) ◽

pp. 823-829 ◽

Cited By ~ 49

Author(s):

Claes‐Ingvar Bjornsson ◽

Claes Fransson

Keyword(s):

Radio Emission ◽

Compton Scattering ◽

X Ray

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The Effects of Inverse Compton Scattering on the Pulsars' Radiation

Symposium - International Astronomical Union ◽

10.1017/s0074180900160450 ◽

1987 ◽

Vol 125 ◽

pp. 59-59

Author(s):

X.-Y. Xia ◽

Z.-G. Deng ◽

G.-J. Qiao ◽

X.-J. Wu ◽

H. Chen

Keyword(s):

Radio Emission ◽

Compton Scattering ◽

Cross Section ◽

Quasi Equilibrium ◽

Polar Cap ◽

Strong Magnetic Fields ◽

Inverse Compton Scattering ◽

Inverse Compton ◽

S Model ◽

Radiative Pressure

Our calculations show that the cross section of the inverse Compton scattering in strong magnetic fields may be larger than that of Thompson scattering by sevaral orders of magnitude in the case of polar cap surface of pulsars. We can also see that when the energy of e± exceeds a certain value, their energy loss caused by the inverse Compton scattering may be larger than the energy gain from electric field in the inner gap, which implies that the e± could not be accelerated to γ = 106. Meanwhile, the electrostatic forces acting on the electrons will be balanced by the radiative pressure if temperature T > 108 K.It is beleived that the surface temperarure for most of pulsars is less than 106 K, in that case the ions of iron can not be emitted from the surface of pulsars. However, the temperarure at the polar cap can be increased to 3×106 through the bombardment of electrons to the polar cap according to R-S model. This quasi-equilibrium state by self-regulating must make the coherent radio emission unstable on the contrary.

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Nonthermal radio emission generated by coherent plasma waves

Astrophysics ◽

10.1007/bf01006079 ◽

1967 ◽

Vol 2 (2) ◽

pp. 87-98 ◽

Cited By ~ 1

Author(s):

V. V. Zaitsev ◽

S. A. Kaplan

Keyword(s):

Radio Emission ◽

Plasma Waves ◽

Nonthermal Radio ◽

Nonthermal Radio Emission ◽

Coherent Plasma

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Generation of pulsar radio emission

International Astronomical Union Colloquium ◽

10.1017/s0252921100060073 ◽

2000 ◽

Vol 177 ◽

pp. 387-388

Author(s):

Yu.E. Lyubarskii

Keyword(s):

Radio Emission ◽

Electromagnetic Waves ◽

Plasma Waves ◽

Pulsar Radio ◽

Longitudinal Waves ◽

Transverse Electromagnetic ◽

Scattering Transforms ◽

Stream Instability ◽

Pulsar Radio Emission

AbstractThe generation of radio emission from plasma waves excited by two-stream instability in pulsar magnetospheres is considered. Induced scattering transforms the excited longitudinal waves into waves that escape freely in the form of transverse electromagnetic waves. It is shown that the spectrum and the luminosity of the generated radio emission are compatible with those observed.

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Limits on absorption from a 332-MHz survey for fast radio bursts

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa616 ◽

2020 ◽

Vol 493 (3) ◽

pp. 4418-4427 ◽

Cited By ~ 4

Author(s):

K M Rajwade ◽

M B Mickaliger ◽

B W Stappers ◽

C G Bassa ◽

R P Breton ◽

...

Keyword(s):

Radio Emission ◽

Compton Scattering ◽

Low Frequency ◽

Radio Bursts ◽

Intensity Mapping ◽

The Past ◽

Upper Limit ◽

Shock Region ◽

Absorption Models ◽

Post Shock

ABSTRACT Fast radio bursts (FRBs) are bright, extragalactic radio pulses whose origins are still unknown. Until recently, most FRBs have been detected at frequencies greater than 1 GHz with a few exceptions at 800 MHz. The recent discoveries of FRBs at 400 MHz from the Canadian Hydrogen Intensity Mapping Experiment (CHIME) telescope have opened up possibilities for new insights about the progenitors while many other low-frequency surveys in the past have failed to find any FRBs. Here, we present results from an FRB survey recently conducted at the Jodrell Bank Observatory at 332 MHz with the 76-m Lovell telescope for a total of 58 d. We did not detect any FRBs in the survey and report a 90${{\ \rm per\ cent}}$ upper limit of 5500 FRBs per day per sky for a Euclidean Universe above a fluence threshold of 46 Jy ms. We discuss the possibility of absorption as the main cause of non-detections in low-frequency (<800 MHz) searches and invoke different absorption models to explain the same. We find that Induced Compton Scattering alone cannot account for absorption of radio emission and that our simulations favour a combination of Induced Compton Scattering and Free-Free Absorption to explain the non-detections. For a free–free absorption scenario, our constraints on the electron density are consistent with those expected in the post-shock region of the ionized ejecta in superluminous supernovae.

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