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arXiv · nucl-ex/0401015

Low amplitude part of the electron detector response and its significance in neutron angular correlation measurements

Abstract

Results of a study of the possibilities to reduce the low amplitude "tail" of the response characteristic of various electron detectors are presented. The main reason of such attribute of all detectors used in electron epectrometry is the energy of several hundreds KeV taken by the backscattered electrons. A simple method of rejecting the events when the electrons are backscattered - the use of a second -"veto" - detector in anticoincidences with the main detector was investigated. The low amplitude "tail" in the response curve could be reduced by a factor of 3 - 4 . The remaining effect - about 1% of the integral has yet no explanation. Additional experiments showed that only \~0.2-0.3% can be related to bremmsstrahlung. The significance of this effect in the study of angular correlations in neutron beta decay was analyzed too with the help of a simplified computer model. As a result, we propose a method of calculating appropriate corrections which promise to reduce the systematic uncertainty in the measurement of the "a" correlation coefficient which going to be carried out in the near future.

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BibTeXRIS

L. Goldin, B. Yerozolimsky. 2004-01-13. Low amplitude part of the electron detector response and its significance in neutron angular correlation measurements. https://arxiv.org/abs/nucl-ex/0401015

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