Pulsar Radiation Mechanisms

Nature ◽  
1970 ◽  
Vol 227 (5257) ◽  
pp. 465-470 ◽  
Author(s):  
P. A. STURROCK
2000 ◽  
Vol 177 ◽  
pp. 457-460
Author(s):  
A. A. da Costa

AbstractThe plasma motion in pulsar magnetospheres is no longer classical, but quasi-classical, following stochastic trajectories, when random curvature radiation of high energetic gamma-ray photons takes place. This implies an extension to the relativistic kinetic theory of plasmas. But with high energies involved other quantum radiative processes become important, in the context of vacuum (quantum) electrodynamics. The consequences for pulsar radiation mechanisms will be outlined.


1981 ◽  
Vol 95 ◽  
pp. 255-261
Author(s):  
V. V. Zheleznyakov

In this report we shall discuss the origin of radiation from the neutron star component of X-ray binary systems whose spectra contain cyclotron lines (Her X-1 and 4U0115+63). A relevant model of the polar region of a neutron star is presented in Figure 1. According to this model the observed X-rays (continuum + cyclotron lines) are generated in the dense plasma atmosphere of a star (in its hot spot heated by accreting matter). The problem of heating the neutron star atmosphere due to accretion has been earlier investigated by Zeldovich and Shakura (1969). Cyclotron lines are formed similarly to the Fraunhofer spectrum of ordinary stars and are absorption lines. For objects such as Her X-1 and 4U0115+63 the cyclotron emission and absorption in the extended accreting column with an inhomogeneous magnetic field should be unessential. Otherwise the accreting column will produce an X-ray continuum devoid of any line type features.


1980 ◽  
Vol 336 (1 Ninth Texas S) ◽  
pp. 409-428 ◽  
Author(s):  
M. Ruderman

1992 ◽  
Vol 128 ◽  
pp. 366-372
Author(s):  
V. Radhakrishnan

The numerous discussions that took place at the colloquium have reemphasized the primary importance of polarization observations and their interpretation for understanding the magnetospheric structure and the radiation mechanisms of pulsars. I have tried to take them into account in the summary at the end of this written version of my review of polarization phenomena, where I also attempt to address some of the questions raised by both observers and theorists as to what message polarization has for the planning of future observations and for the development of theories to explain pulsar radiation mechanisms. Because I feel it is relevant I shall begin with a little history to put things in perspective.


Science ◽  
1974 ◽  
Vol 186 (4158) ◽  
pp. 66-68 ◽  
Author(s):  
R. N. Manchester

Pulsars ◽  
1981 ◽  
pp. 255-261
Author(s):  
V. V. Zheleznyakov

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1865
Author(s):  
Rida Tajau ◽  
Rosiah Rohani ◽  
Mohd Sofian Alias ◽  
Nurul Huda Mudri ◽  
Khairul Azhar Abdul Halim ◽  
...  

In countries that are rich with oil palm, the use of palm oil to produce bio-based acrylates and polyol can be the most eminent raw materials used for developing new and advanced natural polymeric materials involving radiation technique, like coating resins, nanoparticles, scaffold, nanocomposites, and lithography for different branches of the industry. The presence of hydrocarbon chains, carbon double bonds, and ester bonds in palm oil allows it to open up the possibility of fine-tuning its unique structures in the development of novel materials. Cross-linking, reversible addition-fragmentation chain transfer (RAFT), polymerization, grafting, and degradation are among the radiation mechanisms triggered by gamma, electron beam, ultraviolet, or laser irradiation sources. These radiation techniques are widely used in the development of polymeric materials because they are considered as the most versatile, inexpensive, easy, and effective methods. Therefore, this review summarized and emphasized on several recent studies that have reported on emerging radiation processing technologies for the production of radiation curable palm oil-based polymeric materials with a promising future in certain industries and biomedical applications. This review also discusses the rich potential of biopolymeric materials for advanced technology applications.


Universe ◽  
2021 ◽  
Vol 7 (7) ◽  
pp. 210
Author(s):  
Georgii K. Sizykh ◽  
Sergei P. Roshchupkin ◽  
Victor V. Dubov

The process of resonant high-energy electron–positron pairs production by electrons in an X-ray pulsar electromagnetic field is studied theoretically. Under the resonance conditions, the second-order process under consideration effectively reduces into two sequential first-order processes: X-ray-stimulated Compton effect and X-ray–stimulated Breit–Wheeler process. The kinematics of the process is studied in detail: the dependencies of the energy of the scattered electron on its outgoing angle and the energies of the particles of the pair on the outgoing angle of the scattered electron and the opening angle of the pair are obtained. The analysis of the number of different possible particles energies values in the entire range of the angles is also carried out, according to which the energies of the particles of the pair can take up to eight different values at a fixed outgoing angle of the scattered electron and opening angle of the pair. The estimate of the resonant differential probability per unit time of the process, which reaches the maximum value of 24 orders of the value of the non-resonant differential probability per unit time, is obtained. The angular distribution of the differential probability per unit time of the process is analyzed, particularly for the case of high-energy positrons presenting in pulsar radiation.


1999 ◽  
Vol 62 (1) ◽  
pp. 65-86 ◽  
Author(s):  
MAXIM LYUTIKOV

Beam instabilities in the strongly magnetized electron–positron plasma of a pulsar magnetosphere are considered. We analyse the resonance conditions and estimate the growth rates of the Cherenkov and cyclotron instabilities of the ordinary (O), extraordinary (X) and Alfvén modes in two limiting regimes: kinetic and hydrodynamic. The importance of the different instabilities as a source of coherent pulsar radiation generation is then estimated, taking into account the angular dependence of the growth rates and the limitations on the length of the coherent wave–particle interaction imposed by the curvature of the magnetic field lines. We conclude that in the pulsar magnetosphere, Cherenkov-type instabilities occur in the hydrodynamic regime, while cyclotron-type instabilities occur in the kinetic regime. We argue that electromagnetic cyclotron-type instabilities on the X, O and probably Alfvén waves are more likely to develop in the pulsar magnetosphere.


2016 ◽  
Vol 94 (4) ◽  
Author(s):  
V. I. Denisov ◽  
B. N. Shvilkin ◽  
V. A. Sokolov ◽  
M. I. Vasili’ev

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