Summary
We present the inclusive spectra for π0-mesons constructed from the data obtained by Brasil-Japan emulsion chamber experiment with Câmara 15 (40 m2), exposed at Mount Chacaltaya, Bolívia (5220 m, 550 g/cm2), in 1969–70 covering the energy range 15 TeV <E lab < 240 TeV. A comparison with ISR data is presented and it is pointed out that the available data on pion yield are compatible with a production mechanism occurring in two steps: first, uncorrelated clusters are produced (the unique link being, of course, energy-momentum conservation) and, then, they decay isotropically into pions.
Riassunto
Si presentano gli spettri inclusivi per il mesone π0, costruiti dai dati dell’esperimento con camera ad emulsione Brasile-Giappone con la Câmara 15 (40 m2) esposta sul Monte Chacaltaya in Bolívia (5220 m, 550 g/cm2) nel 1969–70 che ha interessato l’intervallo di energia 15 TeV <E lab < 240 TeV. Si fa un confronto con i dati degli ISR e si mette in evidenza che i dati disponibili sulla resa di pioni si conciliano con un meccanismo di produzione che preveda due fasi: prima si producono ammassi non correlati (essendo l’unico legame la conservazione dell’energia-impulso) e quindi essi decadono isotropicamente in pioni.
Реэюме
Мы предлагаем инклюэивные спектры для e0 меэонов, сконструиро?ванные иэ данных, полученных в браэильско-японском зксперименте в змульсионной камере (40 м2), зкспонированной в Боливии (5220 м, 550 г/см2) в 1969–70 годах. Эксперимент охватывает область знергий 15 ТзВ <Eлаб < 240 ТзВ. Проводится сравнение с ISR данными и отмечается, что имеюшиеся данные для пионного выхода согласуются с механиэмом рождения, которое происходит в два зтапа: сначала обраэуются некоррелированные кластеры (единственная свяэь представляет эакон сохранения знергии-импульса) и эатем они иэотропно распадаются на пионы.
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Rodrigues, W.A., Turtelli, A. Pion inclusive distribution at cosmic-ray energies and comparison with ISR data. Nuov Cim A 23, 227–236 (1974). https://doi.org/10.1007/BF02739480
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DOI: https://doi.org/10.1007/BF02739480