FLUCTUATIONS OF Xmax AND PRIMARY PARTICLE MASS COMPOSITION IN THE RANGE OF ENERGY 5 × 10 17 − 3 × 10 19 EV BY YAKUTSK DATA
The experimental distributions of Xmax obtained with the Yakutsk EAS array at fixed energies of 5 × 10 17, 1 × 10 18 and 5 × 10 18 eV are analysed. A recent version of the QGSJET model is used as a tool of our analysis. In the framework of this model, the most adequate mass composition of primary pa...
| Main Authors: | , , , , , |
|---|---|
| Other Authors: | |
| Format: | Text |
| Language: | English |
| Published: |
2004
|
| Subjects: | |
| Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.254.9307 http://arxiv.org/pdf/astro-ph/0411684v2.pdf |
| Summary: | The experimental distributions of Xmax obtained with the Yakutsk EAS array at fixed energies of 5 × 10 17, 1 × 10 18 and 5 × 10 18 eV are analysed. A recent version of the QGSJET model is used as a tool of our analysis. In the framework of this model, the most adequate mass composition of primary particles satisfying the experimental data on Xmax is selected. Keywords: Cosmic Rays; Extensive Air Showers; Mass Composition. A large body of data on charged particles, muons and Cherenkov radiation of EAS in the energy range 1017 − 1019 eV has been accumulated with the Yakutsk EAS array over a thirty-year period of its exposure. During this period, ∼ 106 showers with E0 ≥ 1017 eV have been registered. After 1993, the number of detectors for the charged particles and EAS Cherenkov light has been increased. The accuracy for determination of arrival direction (zenith and azimuth angles) of EAS and the EAS axis location have been considerably improved. This allowed us to estimate more precisely the EAS characteristics, including Xmax, the atmospheric depth at which the shower reaches its maximum. A large number of Cherenkov detectors operating in the individual EAS events as well as the use of a new version of the QGSJET model1 allowed us to perform quantitative |
|---|