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[en] Observations indicate that jets (i.e., charged particle beams) are emitted from the central black hole sources of active galactic nuclei and quasars. Magnetic fields are produced in e(-)-p or e(-)-e(+)-p jets when electrons (and positrons) are slowed with respect to protons in the jets. Interaction with an ambient interstellar gas or external radiation field can cause such drift velocities. Calculations for the magnetic fields and surface electric fields produced in axisymmetric charged particle beams are described. 5 references

[en] This is the first in a series of papers in which we will describe calculations of molecular line emission and infrared continuum radiation from the expanding circumstellar envelopes of red giants that are undergoing rapid mass loss. In this paper we will be concerned primarily with CO line emission from the outer regions of these envelopes. We describe our method of solution, which requires the simultaneous solution of the radiative transfer equation for the CO emission lines, the equations of statistical equilibrium that determine the populations of the rotational levels of the CO molecule, and an energy equation, which determines the kinetic temperature distribution within the envelope if the level populations and radiation field are known. We derive expressions for the heating rate caused by collisions between molecules and dust particles of cylindrical and spherical shape that drift through the gas as a result of radiation pressure. We describe and discuss our solutions which were calculated for a range of physical input parameters. Finally, we compare our calculations to observations of IRC+10216 and discuss refinements in our calculations that will be included in a subsequent paper

[en] The authors previously calculated magnetic fields produced in axisymmetric charged particle beams (jets) in which electrons (electrons and positrons) have drift velocities with respect to protons. In the present paper numerical solutions are compared with Bessel function and helical magnetic field solutions. Magnetic fields are calculated within mildly relativistic, relativistic, and ultrarelativistic jets interacting with the 2.7 K background radiation. A principal conclusion of these calculations is that large-scale magnetic fields with intensities comparable to those within radio galaxies can be generated by the interaction of mildly relativistic jets with the 2.7 K background radiation. Expressions for the radiation from electrons within jets are calculated, and mechanisms for electron accelerators are discussed. 6 references

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[en] High-temperature (Tgreater than or equal to10⁸ K) CNO cycle burning is studied. An overabundance of both ¹⁷O and ¹⁸O is found after times of approximately 10² seconds. For temperatures of 150 and 200 million degrees the ¹⁸O abundance is much larger than the ¹⁷O abundance after burning times of about 10³ seconds. Known uncertainties in the nuclear reaction rates do not alter the conclusions

[en] In this paper we calculate the eigenmodes associated with an ultrarelativistic electron-positron beam traversing a low-energy electron-positron plasma under physical conditions that may exist along open magnetic field lines above pulsar polar caps. We assume that both beam and plasma are cold and charge neutral, and that magnetic field strength and particle density decrease as (1/R)³. In the superstrong magnetic fields near the stellar surface where cyclotron frequencies exceed plasma frequencies, electrostatic waves and associated transverse low-frequency waves are driven unstable by the two-stream type particle distribution. At larger distances above the stellar surface the slow beam cyclotron wave is driven unstable. At even greater radial distance (approximately when particle energy density exceeds magnetic energy density) both the Ordinary and Alfven modes become unstable. All of these instabilities can lead to generation of radiation. If the particle distribution as generated at the stellar surface, assumed to consist of two streams, is modified only by plasma effects, then electrostatic and associated transverse waves may only be unstable near the stellar surface. The beam cyclotron mode which is driven by a two-stream or an inverted particle distribution may be stable. The Ordinary and Afven modes will probably be unstable provided the particles remain cold perpendicular to the magnetic field. The wave modes most likely to play a role in the generation of pulsar radiation are the electrostatic and the associated transverse low-frequency waves generated near the surface and the Ordinary mode provided it becomes unstable within the light cylinder