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Results for “COMPTON EFFECT”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1966

The internal Compton effect

Internal Compton effect, and use of superconducting magnet spectrometer to determine multipolarity assignments

MAGNET↗
DOE OSTI2023

100th Anniversary of the Compton Effect: Its Discovery and Present-Day Impact on Nuclear Physics

This year is the 100th anniversary of the discovery of the Compton effect marked by A. H. Compton’s 1923 Physical Review article. On this occasion, we reflect on the effect’s impact on Nuclear Physics and celebrate the event a century ago and the eminent scientist who made the discovery. Much of the historical comments rely on the article by R. H. Stuewer. A recent Physics Today article presents a historical perspective of Compton’s work and provides more details. The various applications of the Compton effect and its “derivatives” (e.g. inverse Compton scattering) impact many areas of Physics and Chemistry. Here, this short article is restricted to examples taken from the authors' surroundings: the focus is on nuclear-structure experiments with γ-spectroscopic methods and nuclear cross-section measurements relevant for astrophysics.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
NASA NTRS1974

The Compton-Getting effect for low energy particles

The traditional first-order Compton-Getting effect, which relates particle distributions as observed in two frames of reference moving with constant relative velocity, is inadequate for the description of low-energy particles (less than a few hundred keV/nucleon) in the solar system. An exact procedure is given for recovering both isotropic and anisotropic distributions in the solar wind frame from observations made in a spacecraft frame. The method is illustrated by analyzing a particle event observed by an experiment on IMP-7 on Oct. 31, 1972.

Ipavich, F. M.↗
NASA NTRS1974

The Compton-Getting effect for low energy particles

It was found that the traditional first-order Compton-Getting effect, which relates particle distributions as observed in two frames of reference moving with constant relative velocity, is inadequate for the description of low energy particles (less than a few hundred keV/nucleon) in the solar system. An exact procedure is given for recovering both isotropic and anisotropic distributions in the solar wind frame from observations made in a spacecraft frame. The method was illustrated by analyzing a particle event observed on IPM-7.

Ipavich, F. M.↗
NASA NTRS1990

Two-temperature accretion disks with electron-positron pairs - Effects of Comptonized external soft photons

The present account of the effects of soft photons from external sources on two-temperature accretion disks in electron-positron pair equilibrium solves the energy-balance equation for a given radial distribution of the input rate of soft photons, taking into account their bremsstrahlung and Comptonization. Critical rate behavior is investigated as a function of the ratio of the energy flux of incident soft photons and the energy-generation rate. As in a previous study, the existence of a critical accretion rate is established.

Kusunose, Masaaki↗
DOE OSTI2024

Compton rocket effect due to the action of radiation reaction force in degenerate plasma

A closed set of fluid equations with radiation reaction force (RRF) are constructed from the moments of the appropriate single particle kinetic equation describing a relativistic degenerate (high density) electron plasma. The closure, in analogy with the Maxwellian closure for non-degenerate plasmas, is affected via a parametrized Fermi-Dirac distribution. It is shown that the degeneracy increases RRF just as will be predicted from the so-called “Compton Rocket” effect.

Physics↗
NASA NTRS1968

The Compton-getting effect.

Transformation of differential mean and current densities and anisotropy of cosmic ray particles and photons observed in frames of reference relative to each other with isotropic flux

Axford, W. I.↗
NASA NTRS1985

Second-order Compton-Getting effect on arbitrary intensity distribution

Theoretical studies of energetic particles in space are often referred to a special frame of reference. To compare theory with experiment, one has to transform the particle distribution from the special frame to the observer's frame, or vice versa. Various methods have been derived to obtain the directional distribution in the comoving frame from the directional fluxes measured on a spacecraft. These methods have become progressively complicated as increasingly detailed directional particle data become available. A set of 2nd order correct formulae for the transformation of an arbitrary differential intensity distribution, expressed as a series of spherical harmonics, between any two frames in constant relative motion is presented. These formulae greatly simplify the complicated procedures currently in use for the determination of the differential intensity distribution in a comoving frame.

Ng, C. K.↗
NASA NTRS1989

The effects of Compton scattering in X-ray spectra

The ways in which Compton scattering on free electrons influences the continuous spectrum and temperature structure of a hot stellar atmosphere, where most of its radiation is emitted in the 1-10 keV energy range, are discussed. The numerical results pertain to the continuum spectra of X-ray bursters. The formulation and development of the numerical code, which reproduces angle-averaged relativistic Compton scattering of thermal (unpolarized) X-rays in a plane-parallel atmosphere in hydrostatic and radiative equilibrium, are described.

Madej, Jerzy↗
NASA NTRS1969

Are cosmic electrons anisotropic?

Anisotropy of relativistic cosmic ray electrons, considering electron exposure time to synchrotron effects, energy loss from inverse Compton effect, etc

Earl, J. A.↗
DOE OSTI2020

TRT Compton Scattering Data: Comparisons between LLNL and LANL: Pointwise

This memo is one of a pair of reports comparing Compton scattering data in the context of thermal radiation transport (TRT). This document focuses on Pointwise (PW) data while the other report focuses on Multigroup (MG) data. These complementary analyses, via PW comparisons, show if the same physics are used and if fundamental bugs are present, and, via MG comparisons, quantify macroscopic Compton effects such as mean amplification factors. No averaging of Compton data over photon energy is done for the PW comparisons, while lab-dependent numerical resolution choices become relevant for the MG comparisons. This document plots and quantifies differences in PW Compton scattering data between LANL and LLNL for four disparate temperatures on a logarithmically-spaced energy grid. PW comparisons means we use the received LLNL data as-is, without any averaging or integration over energy. In addition to LANL-to-LLNL comparisons, we investigate the impact of numerical choices on LANL PW data. For the purposes of this comparison, we neglect induced scattering.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2020

TRT Compton Scattering Data: Comparisons between LLNL and LANL: Multigroup

This memo is one of a pair of reports comparing Compton scattering data in the context of thermal radiation transport (TRT). This document focuses on Multigroup (MG) data while the other report focuses on Pointwise (PW) data. These complementary analyses, via PW comparisons, show if the same physics are used and if fundamental bugs are present, and, via MG comparisons, quantify macroscopic Compton effects such as mean amplification factors. No averaging of Compton data over photon energy is done for the PW comparisons, while lab-dependent numerical resolution choices become relevant for the MG comparisons. For this MG-comparison report, we make and document the numerical assumptions we use to convert LLNL PW data into MG data. This document plots and quantifies differences in Compton scattering data between MG LANL and LLNL for four disparate temperatures on a logarithmically-spaced photon-energy grid. In addition to LANL and LLNL data, we add a third and fourth independent vote from data generated by Brooks Kinch (LANL postdoc). For the purposes of these comparisons, we neglect induced scattering.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗