Intensity patterns of pionic X-rays emitted from simple molecules

Abstract

Intensity patterns in the Balmer series of pionic X-rays emitted from carbon and oxygen in simple molecules are reported and analysed using a cascade code. It is shown that modifications are needed in the angular momentum distribution at the beginning of the cascade calculation in order to fit the data.

Intensity Patterns of Pionic X Rays Emitted from Some Organic Compounds

“…We used the muon cascade code MUON developed by Akylas and Vogel [12] in order to calculate the X-ray intensity from a given /'(/)• In Order to apply it to the pionic cascade, we revised the code to include the strong nuclear absorption [9,10]. In this calculation, pions were assumed to have an angular momentum distribution, P(/) cc (2 / -h 1) exp(a/) (0 < Z < n -1)…”

“…The pionic X-rays were measured with two Ge low-energy photon spectrometers; one was installed above the target and the other beneath it. The measuring Chamber was filled with helium gas to [9] exclude the disturbance of nitrogen and oxygen in the air. The measurements lasted for 2 to 8 hours.…”

“…The mesonic X-ray intensity pattems as well as the capture ratios are useful for studying these chemical effects because they are influenced by different environments [6][7][8][9], For example, Schneuwly et al have shown that boron nitride and carbon in cubic structures have different muonic X-ray intensity pattems from those in hexagonal stmctures [8], and O'Leary and Jackson have reported that the sugar isomers such as glucose and mannose have different pionic X-ray intensity pattems [9].…”

Pionic carbon/oxygen capture ratios in blood and muscle tissue of pig

“…The question was, therefore, whether this pronounced damage to the inner walls of blood vessels was the result of specific physical interactions of pions with tissues of different compositions or whether it was related to a biological effect of the LET distribution of stopped pions. Several authors (Jackson et a1 1982, Lewis et a1 1982, O'Leary 1984, O'Leary andJackson 1985, Smith J R H er a1 1986, Smith K R et a1 1986) have pointed out the importance of tissue composition regarding the absorption of energy due to different relative contributions of secondary charged particles from the capture of pions in carbon and oxygen. For example, comparing muscle and Perspex, whose C/O capture ratios are 0.12 and 1.76 respectively, the dose difference between these materials is evaluated as 5.5% for a therapeutic pion beam of 170 MeV c-' (Lewis 1985).…”