Cosmic ray photodisintegration and the knee of the spectrum

被引：29

作者：

Candia, J ^{[1
]}

Epele, LN ^{[1
]}

Roulet, E ^{[1
]}

机构：

[1] Natl Univ La Plata, Dept Phys, RA-1900 La Plata, Argentina

来源：

ASTROPARTICLE PHYSICS | 2002年 / 17卷 / 01期

关键词：

D O I：

10.1016/S0927-6505(01)00131-1

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We explore in some detail the scenario proposed to explain the observed knee of the cosmic ray (CR) spectrum as due to the effects of photodisintegration of the CR nuclei by interactions with optical and soft UV photons in the source region. We show that the photon column densities needed to explain the experimental data are significantly lower than those obtained in previous estimations which neglected multinucleon emission in the photodisintegration process. We also treat more accurately the photodisintegration thresholds, we discuss the effects of photopion production processes and the neutron escape mechanism, identifying the physical processes responsible for the qualitative features of the results. This scenario would require the CR nuclei to traverse column densities of similar to5 x 10(27)-2 x 10(28) eV/cm(2) after being accelerated in order to reproduce the observed knee, and predicts that the CR composition should become lighter above similar to10(16) eV. (C) 2002 Elsevier Science B.V. All rights reserved.

引用

页码：23 / 33

页数：11

共 24 条

[11] 2-PERIOD CROSSOVER CLINICAL-TRIAL [J].

HILLS, M ;

ARMITAGE, P .

BRITISH JOURNAL OF CLINICAL PHARMACOLOGY, 1979, 8 (01) :7-20

[12]

JOKIPII JR, 1986, APJ, V312, P170

[13]

KAMPERT KH, ASTROPH0102266

[14]

KAMPERT KH, 1999, P 26 ICRC SALT LAK C

[15] The formation of the cosmic ray energy spectrum by a photon field [J].

Karakula, S. ;

Tkaczyk, W. .

ASTROPARTICLE PHYSICS, 1993, 1 (02) :229-237

[16]

KOBAYAKAWA K, ASTROPH0008209

[17]

PTUSKIN VS, 1993, ASTRON ASTROPHYS, V268, P726

[18] PHOTONUCLEAR INTERACTIONS OF ULTRAHIGH ENERGY COSMIC-RAYS AND THEIR ASTROPHYSICAL CONSEQUENCES [J].

PUGET, JL ;

STECKER, FW ;

BREDEKAMP, JH .

ASTROPHYSICAL JOURNAL, 1976, 205 (02) :638-654

[19] Photodisintegration of ultra-high-energy cosmic rays: A new determination [J].

Stecker, FW ;

Salamon, MH .

ASTROPHYSICAL JOURNAL, 1999, 512 (02) :521-526

[20] Elemental composition of cosmic rays near the knee by multiparameter measurements of air showers [J].

Swordy, SP ;

Kieda, DB .

ASTROPARTICLE PHYSICS, 2000, 13 (2-3) :137-150

← 1 2 3 →