K and l shells ionization by low-energy electron-impact cross-section measurements

• Grant number: 12/22436-2
• Support Opportunities: Research Grants - Visiting Researcher Grant - Brazil
• Start date: March 01, 2013
• End date: February 28, 2014
• Field of knowledge: Physical Sciences and Mathematics - Physics - Atomic and Molecular Physics
• Principal Investigator: Vito Roberto Vanin
• Grantee: Vito Roberto Vanin
• Visiting researcher: Maria Victoria Manso Guevara
• Visiting researcher institution: Universidade Estadual de Santa Cruz (UESC). Pró-Reitoria de Pesquisa e Pós-Graduação, Brazil
• Host Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The injector for the IFUSP microtron electron accelerator was commissioned and delivers a 1.9 MeV electron beam whose main characteristic is to be CW, which favors all experiments where a constant event rate improves the observation of the phenomena, as coincidence or particle production rate measurements. Using this electron beam, we will measure the electron impact inner-shell atomic ionization cross section, using a X-ray semiconductor detector, placing the targets in a target changer inside an irradiation chamber with spectroscopy windows. The electron current will be measured by a resonant cavity, referred to a faraday cup. The available data were obtained 40 years ago, show discrepancies with the calculated values and the performed experiments were hindered by difficulties that we will overcome. Moreover, in heavy atoms, experimental data in the 2 MeV energy region are scarce, despite the fundamental character of this interaction process. The state-of-the art cross-section calculations are performed in the relativistic Born approximation, either with plane or distorted waves, and are expected to describe this phenomenon with fair accuracy. (AU)