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Related papers: Extraordinary Solar Modulation Effects On Galactic…

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At the Voyager 1 spacecraft in the outer heliosphere, after a series of complex intensity changes starting at about May 8th, the intensities of both anomalous cosmic rays (ACR) and galactic cosmic rays (GCR) changed suddenly and decisively…

Geophysics · Physics 2012-12-06 W. R. Webber , F. B. McDonald , A. C. Cummings , E. C. Stone , B. Heikkila , N. Lal

We have determined the solar modulation potential, phi, vs. time that is observed at Voyager 1 and 2 from measurements of the H and He nuclei intensities at a common energy of 250 MeVnuc. The H nuclei have a rigidity 0.7 GV, the He nuclei…

Space Physics · Physics 2017-06-12 W. R. Webber , E. C. Stone , A. C. Cummings , B. Heikkila , N. Lal

This paper describes the unfolding of the solar modulated galactic cosmic ray H and He nuclei spectra beyond ~105 AU in the heliosheath. Between 2008.0 and 2012.3 when Voyager 1 went from about 105 to 120.5 AU the spectral intensities of…

Space Physics · Physics 2013-08-09 W. R. Webber , P. R. Higbie , F. B. McDonald

We have derived background corrected intensities of 3-50 MeV galactic electrons observed by Voyager 1 as it passes through the heliosheath from 95 to 122 AU. The overall intensity change of the background corrected data from the inner to…

Space Physics · Physics 2017-08-09 W. R. Webber , N. Lal , B. Heikkila

A two-dimensional, time-dependent numerical model is used to calculate the modulation of cosmic rays in the heliosphere. Computations are compared to spacecraft observations in the inner and outer heliosphere. It is shown that the model…

High Energy Astrophysical Phenomena · Physics 2013-10-22 Rex Manuel , Stefan Ferreira , Marius Potgieter

Voyager 1 has entered regions of different propagation conditions for energetic cosmic rays in the outer heliosheath beginning at a distance of about 111 AU from the Sun. This conclusion is based on the fact that the low energy 6-14 MeV…

Space Physics · Physics 2015-06-03 W. R Webber , F. B. McDonald , A. C. Cummings , E. C. Stone , B. Heikkila , N. Lal

The detectors of the UltraViolet Spectrographs (UVS) on Voyager 1/2 are recording a background that was earlier assigned to disintegrations in the RTG. We show that it arises instead from Galactic Cosmic Rays (GCRs). We show the 1992-2013…

Astrophysics of Galaxies · Physics 2015-06-18 R. Lallement , J. L. Bertaux , E. Quemerais , B. R. Sandel

The time-dependent modulation of galactic cosmic rays in the heliosphere is studied by computing intensities using a time-dependent modulation model. By introducing recent theoretical advances in the transport coefficients in the model,…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Rex Manuel , Stefan Ferreira , Marius Potgieter

We have obtained the energy spectra of cosmic ray He, B, C, O, Mg, S and Fe nuclei in the range 0.5-1.5 GeV/nuc and above using the penetrating particle mode of the High Energy Telescope, part of the Cosmic Ray Science (CRS) experiment on…

Space Physics · Physics 2017-12-11 W. R. Webber , N. Lal , E. C. Stone , A. C. Cummings , B. Heikkila

The recovery of cosmic ray Carbon nuclei of energy ~20-125 MeV/nuc in solar cycle #23 from 2004 to 2010 has been followed at three locations, near the Earth using ACE data and at V2 between 74-92 AU and also at V1 beyond the heliospheric…

During the recent solar minimum between cycles 23 and 24 (solar minimum $P_{23/24}$) the intensity of Galactic Cosmic Rays (GCRs) measured at the Earth was the highest ever recorded since space age. It is the purpose of this paper to…

Solar and Stellar Astrophysics · Physics 2014-12-04 L. -L. Zhao , G. Qin , M. Zhang , B. Heber

In this paper, we study the galactic cosmic ray (GCR) variations over the solar cycles 23 and 24, with measurements from the NASA's ACE/CRIS instrument and the ground-based neutron monitors (NMs). The results show that the maximum GCR…

Solar and Stellar Astrophysics · Physics 2021-06-23 Shuai Fu , Xiaoping Zhang , Lingling Zhao , Yong Li

We study changes of the galactic cosmic ray (GCR) intensity for the ending period of the solar cycle 23 and the beginning of the solar cycle 24 using neutron monitors experimental data. We show that an increase of the GCR intensity in 2009…

Solar and Stellar Astrophysics · Physics 2015-04-06 M. V. Alania , R. Modzelewska , A. Wawrzynczak

When the Galactic Cosmic Rays (GCRs) entering the heliosphere, they encounter the solar wind plasma, and their intensity is reduced, so-called solar modulation. The modulation is caused by the combination of a few factors, such as particle…

High Energy Astrophysical Phenomena · Physics 2023-09-07 Jieteng Jiang , Sujie Lin , Lili Yang

Galactic Cosmic Rays (GCRs) have to travel through the heliosphere before they interact with the Earth's atmosphere. During this, they are deflected by the Sun's magnetic field, causing variations in this field to imprint on the flux,…

Since crossing the heliopause on August 25, 2012, Voyager 1 observed reductions in galactic cosmic ray count rates caused by a time-varying depletion of particles with pitch angles near 90-deg, while intensities of particles with other…

Space Physics · Physics 2019-05-30 J. S. Rankin , E. C. Stone , A. C. Cummings , D. J. McComas , N. Lal , B. C. Heikkila

The paper describes differences in the intensity as a function of radial distance of anomalous and galactic cosmic rays in the N-S heliosheaths as observed by the Voyager 1 and 2 spacecraft respectively. The anomalous cosmic ray (ACR)…

Space Physics · Physics 2014-03-14 W. R. Webber , D. S. Intriligator

We study solar modulation of galactic cosmic rays (GCRs) during the deep solar minimum, including the declining phase, of solar cycle 23 and compare the results of this unusual period with the results obtained during similar phases of the…

Solar and Stellar Astrophysics · Physics 2013-12-03 O. P. M. Aslam , Badruddin

Voyager 1 has explored the solar wind-interstellar medium interaction region between the terminal shock and heliopause following the intensity distribution of galactic cosmic ray protons above 200 MeV energy. Before this component reached…

Solar and Stellar Astrophysics · Physics 2015-09-09 J. J. Quenby , W. R. Webber

When traveling in the heliosphere, Galactic cosmic rays (GCRs) are subjected to the solar modulation effect, a quasiperiodical change of their intensity caused by the 11-year cycle of solar activity. Here we investigate the association of…

Solar and Stellar Astrophysics · Physics 2022-11-22 Nicola Tomassetti , Bruna Bertucci , Emanuele Fiandrini
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