CRRES observations of radiation belt protons: 1. Data overview and steady state radial diffusion

Albert, J. M.; Ginet, G. P.; Gussenhoven, M. S.

doi:10.1029/97ja02869

Cited by 44 publications

(75 citation statements)

References 32 publications

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“…Their LET is greater during solar minimum when solar wind had the most intense speed. The population of trapped protons is believed to be resulted from Cosmic Ray Albedo Neutron Decay (CRAND) which is the product of cosmic ray interacting with the Earth's atmosphere [10]. Hence, they followed the GCR fluxes that are anticorrelated with the solar activity.…”

Section: Resultsmentioning

confidence: 99%

Radiation Dose Analysis of Galactic Cosmic Ray in Low Earth Orbit/Near Equatorial Orbit

Suparta

Zulkeple

2014

J. Phys.: Conf. Ser.

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Abstract. Space environment contained harmful radiation that posed risk to spacecraft orbiting the Earth. In this paper, we looked into radiation doses caused by galactic cosmic ray (GCR) towards satellites orbiting in low earth orbit (LEO) near Earth's equator (NEqO) and compared them with doses caused by solar energetic particles (SEP) and trapped particles to determine the damage level of GCR. The radiation doses included linear energy transfer (LET) and nonionizing energy loss (NIEL) through a 1mm gallium arsenide (GaAs) planar geometry by using Space Environment Information System (SPENVIS) method. The orbital data followed Malaysian Razaksat satellite at 685km altitude and 9° inclination during selected solar minimum and solar maximum from solar cycles 21 to 24. We found that trapped particles gave the highest LET and no SEP was detected in SPENVIS. The LET values tend to be higher during solar minimum for trapped particles and GCR, corresponding to their anti-correlated fluxes with the solar activity. However, the NIEL values for GCR in solar cycle 23 did not follow the anti-correlation pattern.

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Section: Resultsmentioning

confidence: 99%

Radiation Dose Analysis of Galactic Cosmic Ray in Low Earth Orbit/Near Equatorial Orbit

Suparta

Zulkeple

2014

J. Phys.: Conf. Ser.

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“…3 in Albert et al (1998), a ratio of rates of Coulomb losses of protons with µ = 1 and 10 keV nT −1 (100 and 1000 MeV G −1 ) is equal to ∼ 110. The ratio is equal to the ratio of corresponding values of the function F (µ) on L = 3 (see Eq.…”

Section: Comparison With Results Of Other Workmentioning

confidence: 99%

“…Further, in the works on the modeling of the protons of Earth's radiation belts (e.g., Cornwall, 1972;Claflin and White, 1974;Croley et al, 1976;Spjeldvik, 1977;Albert et al, 1998) Eqs. (9)- (11) were usually used for Coulomb losses.…”

Section: Comparison With Results Of Other Workmentioning

confidence: 99%

“…In Albert et al (1998) the fluxes of protons with E ∼ 1-100 MeV for L ≤ 3, measured on the CRRES, were modeled based on the theory of radial diffusion of particles. For rate of Coulomb losses of protons an expression similar to our Eq.…”

Section: Comparison With Results Of Other Workmentioning

confidence: 99%

“…And if at the given value of µ at the certain L we have a positive slope of the spectrum, ∂f * /∂µ > 0, then the Coulomb losses do not involve reduction but an increase in density of the particles in this cell {µ, L}. (2), for a quiet proton belt constructed according to Williams (1981) for ISEE-1 (thick curves), Fritz and Spjeldvik (1981) for Explorer-45 (light circles) and Albert et al (1998) for CRRES (dotted curves).…”

Section: The Coulomb Losses Of Protonsmentioning

confidence: 99%

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Radial dependence of ionization losses of protons of the Earth's radiation belts

Kovtyukh

2016

Ann. Geophys.

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Abstract. Coulomb losses and charge exchange of protons are considered in detail. On the basis of modern models of the plasmasphere and the exosphere, the radial dependences of the rates of ionization losses of protons, with µ from 0.3 to 10 keV nT −1 , of the Earth's radiation belts near the equatorial plane are calculated for quiet periods. For calculation of Coulomb losses of protons we used data of ISEE-1 satellite (protons with energy from 24 to 2081 keV) on L from 3 to 9, data of Explorer-45 satellite (protons with energy from 78.6 to 872 keV) on L from 3 to 5 and data of CRRES satellite (protons with energy from 1 to 100 MeV) on L ≤ 3 (L is the McIlwain parameter). It is shown that with decreasing L the rate of ionization losses of protons of the radiation belts is reduced; for protons with µ > 1.2 keV nT −1 in a narrow region ( L ∼ 0.5) in the district of plasmapause in this dependence may form a local minimum of the rate. We found that the dependence from µ of the boundary on L between Coulomb losses and charge exchange of the trapped protons with hydrogen atoms is well approximated by the function L b = 4.71µ 0.32 , where, and at L > L b (µ) dominates charge exchange of protons. We found the effect of subtracting the Coulomb losses from the charge exchange of protons of the radiation belts at low µ and L, which can simulate a local source of particles.

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Large anisotropies of >60 MeV protons throughout the inner belt observed with the Van Allen Probes mission

Mazur

O’Brien

Looper

et al. 2014

Geophys. Res. Lett.

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We report large directional anisotropies of >60 MeV protons using instrumentation on the Van Allen Probes. The combination of a spinning satellite and measurements from the Relativistic Proton Spectrometer instruments that are insensitive to protons outside the instrument field of view together yield a new look at proton radial gradients. The relatively large proton gyroradius at 60 MeV couples with the radial gradients to produce large (maximum~10:1) flux anisotropies depending on (i) whether the proton guiding center was above or below the Van Allen Probes spacecraft and (ii) the sign of the local flux gradient. In addition to these newly measured anisotropies, below~2000 km we report a new effect of systematically changing minimum altitude on some proton drift shells that further modulates the anisotropy caused by the atmosphere. This discovery may offer a new way of monitoring changes to the loss of inner belt protons into the Earth's atmosphere.

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CRRES observations of radiation belt protons: 1. Data overview and steady state radial diffusion

Cited by 44 publications

References 32 publications

Radiation Dose Analysis of Galactic Cosmic Ray in Low Earth Orbit/Near Equatorial Orbit

Radiation Dose Analysis of Galactic Cosmic Ray in Low Earth Orbit/Near Equatorial Orbit

Radial dependence of ionization losses of protons of the Earth's radiation belts

Large anisotropies of >60 MeV protons throughout the inner belt observed with the Van Allen Probes mission

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