Abstract:
:A single experimental apparatus has been designed to allow measurements of stopping cross-sections of materials in liquid and vapour phase, for alpha particles, using an indirect method. The method, in which residual energies for increasing absorber thicknesses are obtained and differentiated, has been used in a number of investigations of phase effects in stopping power. As a set of preliminary experiments, the stopping cross-sections of He, N2, Ar, CH4 and air for alpha particles have been measured, to allow overall assessment of measurement and data analysis procedures by comparison with other published results. Such comparison suggests that the absolute uncertainty of the techniques employed in unlikely to exceed 4 or 5%. Some of the problems associated with indirect measurements of stopping power are discussed.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Thwaites DIdoi
10.1088/0031-9155/25/5/004subject
Has Abstractpub_date
1980-09-01 00:00:00pages
865-75issue
5eissn
0031-9155issn
1361-6560journal_volume
25pub_type
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