%A"Caporali, C" %A"Guerra, A S" %A"Laitano, R F" %A"Pimpinella, M [ENEA-Casaccia, Inst. Nazionale di Meterologia delle Radiazioni Ionizzanti, Rome (Italy). Dipt. Ambiente]" %D1996 %I; International Atomic Energy Agency, Vienna (Austria) %2 %J[] %K56 BIOLOGY AND MEDICINE, APPLIED STUDIES, 44 INSTRUMENTATION, INCLUDING NUCLEAR AND PARTICLE DETECTORS, IONIZATION CHAMBERS, BEAM MONITORING, QUALITY FACTOR, CALIBRATION, DOSIMETRY, MEASURING METHODS, PHANTOMS, RADIATION DOSES, RADIOTHERAPY %PMedium: ED; Size: pp. 171-178 %TAbsorbed dose beam quality factors for cylindrical ion chambers: Experimental determination at 6 and 15 MV photon beams %XIon chambers calibrated in terms of absorbed dose to water need an additional factor conventionally designed by k{sub Q} in order to determine the absorbed dose. The quantity k{sub Q} depends on beam quality and chamber characteristics. Rogers and Andreo provided calculations of the k{sub Q} factors for most commercially available ionization chambers for clinical dosimetry. Experimental determinations of the k{sub Q} factors for a number of cylindrical ion chambers have been made and are compared with the calculated values so far published. Measurements were made at 6 MV and 15 MV clinical photon beams at a point in water phantom where the ion chambers and a Fricke dosimeter were alternatively irradiated. The uncertainty on the experimental k{sub Q} factors resulted about {+-} 0.6%. The theoretical and experimental k{sub Q} values are in fairly good agreement. (author). 12 refs, 3 tabs. %0Conference %NIAEA-TECDOC-896; CONF-940864-;Journal ID: ISSN 1011-4289; Other: ON: DE97614216; TRN: XA9642857017933 %1 %CIAEA %Rhttps://doi.org/ Journal ID: ISSN 1011-4289; Other: ON: DE97614216; TRN: XA9642857017933 INIS %GEnglish