The first observation of sulfur in anomalous cosmic rays by the Geotail and the wind spacecrafts

T. Takashima, T. Doke, T. Hayashi, J. Kikuchi, M. Kobayashi, H. Shirai, N. Takehana, M. Ehara, Y. Yamada, S. Yanagita, Nobuyuki Hasebe, T. Kashiwagi, C. Kato, K. Munakata, T. Kohno, K. Kondoh, H. Murakami, A. Nakamoto, T. Yanagimachi, D. V. ReamesT. T. Von Rosenvinge

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

The Geotail high-energy particle instruments have observed cosmic-ray particles in the energy range from 3 MeV n-1 to 150 MeV n-1 at 1 AU during the period 1992 September-1995 August. A remarkable enhancement of anomalous cosmic-ray (ACR) N, O, Ne, and C is observed during the period. A measurable enhancement of the sulfur flux below about 20 MeV n-1 was observed. This is the first evidence showing the existence of sulfur in the anomalous component. The flux increase of anomalous sulfur, with a first ionization potential (FIP) of 10.4 eV, is smaller than that of ACR carbon with an FIP of 11.3 eV and much smaller than those of high-FIP elements, which suggests that the fractions of neutral carbon and sulfur atoms are significantly low in the very local interstellar medium.

Original languageEnglish
JournalAstrophysical Journal
Volume477
Issue number2 PART II
Publication statusPublished - 1997
Externally publishedYes

Fingerprint

cosmic ray
cosmic rays
spacecraft
sulfur
ionization potentials
ionization
augmentation
carbon
particle energy
energy
atoms
particle

Keywords

  • Cosmic rays
  • ISM: general

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

Takashima, T., Doke, T., Hayashi, T., Kikuchi, J., Kobayashi, M., Shirai, H., ... Von Rosenvinge, T. T. (1997). The first observation of sulfur in anomalous cosmic rays by the Geotail and the wind spacecrafts. Astrophysical Journal, 477(2 PART II).

The first observation of sulfur in anomalous cosmic rays by the Geotail and the wind spacecrafts. / Takashima, T.; Doke, T.; Hayashi, T.; Kikuchi, J.; Kobayashi, M.; Shirai, H.; Takehana, N.; Ehara, M.; Yamada, Y.; Yanagita, S.; Hasebe, Nobuyuki; Kashiwagi, T.; Kato, C.; Munakata, K.; Kohno, T.; Kondoh, K.; Murakami, H.; Nakamoto, A.; Yanagimachi, T.; Reames, D. V.; Von Rosenvinge, T. T.

In: Astrophysical Journal, Vol. 477, No. 2 PART II, 1997.

Research output: Contribution to journalArticle

Takashima, T, Doke, T, Hayashi, T, Kikuchi, J, Kobayashi, M, Shirai, H, Takehana, N, Ehara, M, Yamada, Y, Yanagita, S, Hasebe, N, Kashiwagi, T, Kato, C, Munakata, K, Kohno, T, Kondoh, K, Murakami, H, Nakamoto, A, Yanagimachi, T, Reames, DV & Von Rosenvinge, TT 1997, 'The first observation of sulfur in anomalous cosmic rays by the Geotail and the wind spacecrafts', Astrophysical Journal, vol. 477, no. 2 PART II.
Takashima T, Doke T, Hayashi T, Kikuchi J, Kobayashi M, Shirai H et al. The first observation of sulfur in anomalous cosmic rays by the Geotail and the wind spacecrafts. Astrophysical Journal. 1997;477(2 PART II).
Takashima, T. ; Doke, T. ; Hayashi, T. ; Kikuchi, J. ; Kobayashi, M. ; Shirai, H. ; Takehana, N. ; Ehara, M. ; Yamada, Y. ; Yanagita, S. ; Hasebe, Nobuyuki ; Kashiwagi, T. ; Kato, C. ; Munakata, K. ; Kohno, T. ; Kondoh, K. ; Murakami, H. ; Nakamoto, A. ; Yanagimachi, T. ; Reames, D. V. ; Von Rosenvinge, T. T. / The first observation of sulfur in anomalous cosmic rays by the Geotail and the wind spacecrafts. In: Astrophysical Journal. 1997 ; Vol. 477, No. 2 PART II.
@article{5a138ccfed24483daee161bd70f86ed3,
title = "The first observation of sulfur in anomalous cosmic rays by the Geotail and the wind spacecrafts",
abstract = "The Geotail high-energy particle instruments have observed cosmic-ray particles in the energy range from 3 MeV n-1 to 150 MeV n-1 at 1 AU during the period 1992 September-1995 August. A remarkable enhancement of anomalous cosmic-ray (ACR) N, O, Ne, and C is observed during the period. A measurable enhancement of the sulfur flux below about 20 MeV n-1 was observed. This is the first evidence showing the existence of sulfur in the anomalous component. The flux increase of anomalous sulfur, with a first ionization potential (FIP) of 10.4 eV, is smaller than that of ACR carbon with an FIP of 11.3 eV and much smaller than those of high-FIP elements, which suggests that the fractions of neutral carbon and sulfur atoms are significantly low in the very local interstellar medium.",
keywords = "Cosmic rays, ISM: general",
author = "T. Takashima and T. Doke and T. Hayashi and J. Kikuchi and M. Kobayashi and H. Shirai and N. Takehana and M. Ehara and Y. Yamada and S. Yanagita and Nobuyuki Hasebe and T. Kashiwagi and C. Kato and K. Munakata and T. Kohno and K. Kondoh and H. Murakami and A. Nakamoto and T. Yanagimachi and Reames, {D. V.} and {Von Rosenvinge}, {T. T.}",
year = "1997",
language = "English",
volume = "477",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd.",
number = "2 PART II",

}

TY - JOUR

T1 - The first observation of sulfur in anomalous cosmic rays by the Geotail and the wind spacecrafts

AU - Takashima, T.

AU - Doke, T.

AU - Hayashi, T.

AU - Kikuchi, J.

AU - Kobayashi, M.

AU - Shirai, H.

AU - Takehana, N.

AU - Ehara, M.

AU - Yamada, Y.

AU - Yanagita, S.

AU - Hasebe, Nobuyuki

AU - Kashiwagi, T.

AU - Kato, C.

AU - Munakata, K.

AU - Kohno, T.

AU - Kondoh, K.

AU - Murakami, H.

AU - Nakamoto, A.

AU - Yanagimachi, T.

AU - Reames, D. V.

AU - Von Rosenvinge, T. T.

PY - 1997

Y1 - 1997

N2 - The Geotail high-energy particle instruments have observed cosmic-ray particles in the energy range from 3 MeV n-1 to 150 MeV n-1 at 1 AU during the period 1992 September-1995 August. A remarkable enhancement of anomalous cosmic-ray (ACR) N, O, Ne, and C is observed during the period. A measurable enhancement of the sulfur flux below about 20 MeV n-1 was observed. This is the first evidence showing the existence of sulfur in the anomalous component. The flux increase of anomalous sulfur, with a first ionization potential (FIP) of 10.4 eV, is smaller than that of ACR carbon with an FIP of 11.3 eV and much smaller than those of high-FIP elements, which suggests that the fractions of neutral carbon and sulfur atoms are significantly low in the very local interstellar medium.

AB - The Geotail high-energy particle instruments have observed cosmic-ray particles in the energy range from 3 MeV n-1 to 150 MeV n-1 at 1 AU during the period 1992 September-1995 August. A remarkable enhancement of anomalous cosmic-ray (ACR) N, O, Ne, and C is observed during the period. A measurable enhancement of the sulfur flux below about 20 MeV n-1 was observed. This is the first evidence showing the existence of sulfur in the anomalous component. The flux increase of anomalous sulfur, with a first ionization potential (FIP) of 10.4 eV, is smaller than that of ACR carbon with an FIP of 11.3 eV and much smaller than those of high-FIP elements, which suggests that the fractions of neutral carbon and sulfur atoms are significantly low in the very local interstellar medium.

KW - Cosmic rays

KW - ISM: general

UR - http://www.scopus.com/inward/record.url?scp=21744432815&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=21744432815&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:21744432815

VL - 477

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 2 PART II

ER -