How can FAST improve study of the pulsar emission mechanism and magnetospheric dynamics?

Giant radio pulses (GRPs) are sporadic bursts emitted by some pulsars that last a few microseconds and are hundreds to thousands of times brighter than regular pulses from these sources. The only GRP-associated emission outside of radio wavelengths is from the Crab Pulsar, where optical emission is enhanced by a few percentage points during GRPs. We observed the Crab Pulsar simultaneously at x-ray and radio wavelengths, finding enhancement of the x-ray emission by 3.8 ± 0.7% (a 5.4σ detection) coinciding with GRPs. This implies that the total emitted energy from GRPs is tens to hundreds of times higher than previously known. We discuss the implications for the pulsar emission mechanism and extragalactic fast radio bursts.

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Radius-to-Frequency Mapping in the Radio Pulsar Emission Mechanism

International Astronomical Union Colloquium ◽

10.1017/s0002731600154952 ◽

1992 ◽

Vol 128 ◽

pp. 143-146

Author(s):

S. E. Thorsett

Keyword(s):

General Feature ◽

Low Frequency ◽

Radio Pulsar ◽

Emission Mechanism ◽

Polar Cap ◽

Pulsar Emission ◽

Pulsar Timing ◽

Average Profile ◽

Different Altitudes

AbstractA general feature of many models of the pulsar emission mechanism is that radiation of different frequencies is produced at different altitudes above the polar cap. The broadening of pulse components and increasing separation between components at low frequency is in general agreement with these theories. We review the available average profile and pulsar timing observations and discuss the implications for theories of radius-to-frequency mapping.

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Probing X-ray emission in different modes of PSR J1023+0038 with a radio pulsar scenario

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936312 ◽

2019 ◽

Vol 629 ◽

pp. L8 ◽

Cited By ~ 3

Author(s):

S. Campana ◽

A. Miraval Zanon ◽

F. Coti Zelati ◽

D. F. Torres ◽

M. C. Baglio ◽

...

Keyword(s):

Neutron Star ◽

Spectral Properties ◽

Source Parameters ◽

High Mode ◽

Radio Pulsar ◽

Emission Model ◽

Emission Mechanism ◽

Pulsar Emission ◽

X Ray ◽

Pulsar Wind

Transitional pulsars provide us with a unique laboratory to study the physics of accretion onto a magnetic neutron star. PSR J1023+0038 (J1023) is the best studied of this class. We investigate the X-ray spectral properties of J1023 in the framework of a working radio pulsar during the active state. We modelled the X-ray spectra in three modes (low, high, and flare) as well as in quiescence, to constrain the emission mechanism and source parameters. The emission model, formed by an assumed pulsar emission (thermal and magnetospheric) plus a shock component, can account for the data only adding a hot dense absorber covering ∼30% of the emitting source in high mode. The covering fraction is similar in flaring mode, thus excluding total enshrouding, and decreases in the low mode despite large uncertainties. This provides support to the recently advanced idea of a mini-pulsar wind nebula (PWN), where X-ray and optical pulsations arise via synchrotron shock emission in a very close (∼100 km, comparable to a light cylinder), PWN-like region that is associated with this hot absorber. In low mode, this region may expand, pulsations become undetectable, and the covering fraction decreases.

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GRO J1744-28: The Luminosity and Pulsar Emission Mechanism

Physica Scripta ◽

10.1088/0031-8949/1998/t77/027 ◽

1998 ◽

Vol T77 ◽

pp. 91-92

Author(s):

S Y Sazonov

Keyword(s):

Emission Mechanism ◽

Pulsar Emission

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Pulsar Emission Mechanism

Nature ◽

10.1038/223277a0 ◽

1969 ◽

Vol 223 (5203) ◽

pp. 277-279 ◽

Cited By ~ 28

Author(s):

F. C. MICHEL ◽

W. H. TUCKER

Keyword(s):

Emission Mechanism ◽

Pulsar Emission

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Correlation between the X-ray Spectra of Young Pulsars and their Wind Nebulae

Symposium - International Astronomical Union ◽

10.1017/s0074180900194331 ◽

2003 ◽

Vol 214 ◽

pp. 163-166

Author(s):

E. V. Gotthelf

Keyword(s):

Linear Relationship ◽

Current Theory ◽

Shock Acceleration ◽

Observational Constraints ◽

Emission Mechanism ◽

Pulsar Emission ◽

X Ray ◽

Pulsar Wind

A significant correlation is discovered between the X-ray spectra of young pulsars (PSRs) and that of their associated wind nebulae (PWNe). For a sample of nine bright Crab-like pulsar systems observed with the Chandra X-ray observatory, we report a linear relationship between the photon indices for the PWNe and those of the phase-averaged pulsar emission, where ΓPWN = 0.72 ± 0.13 × ΓPSR + 0.86 ± 0.20. Furthermore, we find that the spectral slopes of younger, more energetic, pulsars tend to be steeper. These results confirm a consistent pulsar emission mechanism and provide important new observational constraints on the current theory of shock acceleration models for pulsar wind emission.

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Laboratory study of coherent curvature radiation as a pulsar emission mechanism

Astrophysics and Space Science ◽

10.1007/bf00652932 ◽

1981 ◽

Vol 80 (2) ◽

pp. 307-321 ◽

Cited By ~ 2

Author(s):

Gregory Benford ◽

David Tzach

Keyword(s):

Laboratory Study ◽

Emission Mechanism ◽

Pulsar Emission ◽

Curvature Radiation

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The Status of Pulsar Emission Theory

International Astronomical Union Colloquium ◽

10.1017/s0252921100061066 ◽

2000 ◽

Vol 177 ◽

pp. 721-726 ◽

Cited By ~ 1

Author(s):

D.B. Melrose

Keyword(s):

Plasma Frequency ◽

Emission Mechanism ◽

Number Density ◽

Langmuir Turbulence ◽

Pulsar Emission ◽

Pulsar Radio ◽

Testable Prediction ◽

The Status ◽

Statistical Sense ◽

Pulsar Radio Emission

AbstractIt is argued that there is now a preferred pulsar radio emission mechanism, involving beam-driven Langmuir turbulence. A testable prediction is that, at least in a statistical sense, features in the spectra of pulsars should scale with the plasma frequency,υGJ, implied by the Goldreich-Julian number density.

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Multi Radio Frequency Observations of Pulsars

Symposium - International Astronomical Union ◽

10.1017/s0074180900092846 ◽

1981 ◽

Vol 95 ◽

pp. 177-185

Author(s):

Norbert Bartel

Keyword(s):

Radio Emission ◽

Frequency Dependence ◽

Coherence Time ◽

List Type ◽

Focal Points ◽

Type Number ◽

Emission Mechanism ◽

Frequency Range ◽

Pulsar Emission ◽

Points Of Interest

An investigation of the frequency dependence of the radio emission of pulsars promises to contribute considerably to the understanding of such outstanding questions as: 1.Is the emission mechanism narrowband or broadband?2.What is the coherence time of the radiation?3.Does a radius-to-frequency mapping exist?4.Is pulsed radiation absorbed in the magnetosphere?The 100-m telescope in Effelsberg is satisfactorily sensitive in the GHz frequency range so that we could observe averaged pulses up to 22.7 GHz (Bartel et al., 1977; Bartel et al., 1978) and single pulses at 8.8 GHz (Bartel et al., 1980a), which are the highest radio frequencies respectively at which pulsars have been detected. Therefore quite naturally the analysis of the frequency dependent pulsar emission became one of the focal points of interest in pulsar research at the MPIfR.

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