01716naa a2200205 a 450000100080000000500110000800800410001910000200006024500510008026000090013130000130014052011290015365300140128265300110129665300170130765300140132470000200133870000200135877301320137810265472010-03-09       1988    bl ---       0--  u    #d1 aCARVALHO, A. A.  aA new pulsed pyroelectric radiation dosimeter.  c1988  ap.II-25.  aWe describe a new type of radiation dosimeter for the diagnostic X-ray region using a pyroelectric detector. The pulsed pyroelectric radiation dosimeter (PPERD) is a system constituted by a X-ray beam commutator, a pyroelectric chamber, a pre-amplifier and an electronic peak detector. The pyroelectric chamber consists basically of a lead zirconium titanate (PZT) ceramic (17mm x 17mm and 3mm thick) on a nylon support. The chamber is evacuated to about 1mm Hg. The thickness of the detector is such that it absorbed more than 99% of the X-ray beam used in these studies. The pyroelectric element itself absorbs a X-ray pulse and provides a voltage proportional to the energy absorbed. The PPERD has the following characteristics for diagnostic X-ray beams: 1) it responds linearly to the radiation intensity for a given radiation spectrum; 2) it responds linearly to the radiatin energy fluence rate; 3) the pyroelectric chamber is simple to construct, inexpensive and rugged; 4) the lower detection limit of energy fluence rate range and of exposure rate range are respectively 20mW/m2 and 9,0.10E-6C.KgE-1 sE-1 (35mR/s).  aDosimeter  aPulsed  aPyroelectric  aRadiation1 aMASCARENHAS, S.1 aPAULA, M. H. de  tIn: INTERNATIONAL SYMPOSIUM ON RADIATION PHYSICS, 4., Oct. 1988, São Paulo, SP. Book of abstracts... São Paulo: [s.n.], 1988.