Beam analysis spectrometer for relativistic heavy ions

Determination of water absorbed dose in a carbon ion beam using thimble ionization chambers

“…Since the experimental proton data for the w value in figure 2 do not show any significant increase down to energies of 0.1 MeV, use of the constant value down to 1 MeV/u appears to be a reasonable assumption for any depth including that of the Bragg peak. The dependence on particle type appears to be negligible for three reasons: (a) the compilation of figure 2 does not support an evidence of a Z dependence; (b) according to Verhey and Lyman (1992), the difference between the w values of protons and light ions up to Z = 10 should be smaller than 1% at energies above 5 MeV/u; and (c) Schimmerling et al (1982) have reported on measurements in nitrogen with different particles (9 Z 14). They did not find a significant variation with Z.…”

“…Compilation of data on w/e values in air for protons, α-particles and light ions. Full circles refer to proton data(Huber et al 1985, Willems et al 1983, Gerthsen 1930, Larson 1958, Thomas and Burke 1985, Jentschke 1940, Hiraoka et al 1989, Siebers et al 1995, Denis et al 1990, Petti et al 1986, Bakker and Segrè 1951 compiled byGrosswendt and Baek (1998), plusses refer to alphas(ICRU 1979, Chapell and Sparrow 1967, Ishiwari et al 1956 and open squares refer to light ions(Kanai et al 1993, Hiraoka et al 1989, Schimmerling et al 1982, Thomas et al 1980, Stephens et al 1976. The full line is the value of 34.8 recommended for protons by ICRU 59 (1998), the dotted lines represent a ±4% uncertainty interval.…”

Heavy-Ion Radiobiology: Cellular Studies

“…W values for the higher energy, high atomic number Bevalac beams have been characterized by several methods including time-of-flight measurements that correlate physical factors such as fragmentation and LET distributions (Schimmerling et al, 1976(Schimmerling et al, , 1983Stephens et al, 1976;Schimmerling, 1980;Thomas et al, 1980;Thomas, 1982). Results to date show that in nitrogen the same W applies to a wide range of particles and energies (e.g., carbon to argon from 100 to 700 MeV/u).…”

“…(1) comparisons of absorbed dose measurements with calculations of absorbed dose based on the geometric properties of the irrradiated volumes within the ion chambers and using for each beam the same values of W, the average energy required to make one ion pair in nitrogen gas (Thomas et al, 1980;Thomas, 1982;Schimmerling et al, 1983); (2) ; and (5) absolute dose intercomparisons of charged particle beams (Smith, 1982), including Bevalac dosimetry, are being conducted by a multilaboratory dosimetry group.…”

Some Comments on the Concepts of Dose and Dose Equivalent

“…If we are to predict response, we must know the action cross sections and the particle-energy spectra. These spectra are presently only available for neutrons (Caswell and Coyne 1972) and are presently being studied for heavy ion beams (Schimmerling et al 1983). Where the particle-energy spectra and the low-LET contamination are known, the equations of Table 1 make it possible to calculate cellular survival from cellular radiosensitivity parameters (Katz and Sharma, 1973;Katz and Sharma 1974;Roth and Katz, 1980).…”