Abstract
We have performed high-energy electron observations using balloon-borne emulsion chambers, and derived the cosmic-ray electron spectrum in the energy range from 30 GeV to 3 TeV. For the calibration of the emulsion chambers, we have also carried out beam tests of 50 GeV, 200 GeV, and 250 GeV electrons at CERN-SPS. The Landau-Pomeranchuk-Migdal (LPM) effect predicts the reduction of amplitude for bremsstrahlung photon emission. It affects to the depth of the first electron-positron pair of the electron-induced shower, the so-called shower starting point. In the emulsion chambers, we can measure the shower starting points for high-energy electrons with the position resolution of 1 µm. From the observations of accelerator-beam electrons of 200 GeV and 250 GeV, and cosmic-ray electrons above 400 GeV, we found the direct evidence of suppression of the bremsstrahlung cross sections due to the LPM effect.
| Original language | English |
|---|---|
| Title of host publication | Proceedings of the 33rd International Cosmic Rays Conference, ICRC 2013 |
| Publisher | Sociedade Brasileira de Fisica |
| Volume | 2013-October |
| ISBN (Electronic) | 9788589064293 |
| Publication status | Published - 2013 Jan 1 |
| Event | 33rd International Cosmic Rays Conference, ICRC 2013 - Rio de Janeiro, Brazil Duration: 2013 Jul 2 → 2013 Jul 9 |
Other
| Other | 33rd International Cosmic Rays Conference, ICRC 2013 |
|---|---|
| Country | Brazil |
| City | Rio de Janeiro |
| Period | 13/7/2 → 13/7/9 |
Fingerprint
Keywords
- Balloon
- Electron
- Emulsion chambers
- LPM effect
ASJC Scopus subject areas
- Nuclear and High Energy Physics