Chudakov effect for the most probable value of high-energy electron–positron pair ionization loss in thin targets

Abstract

The ionization loss of a high-energy electron–positron pair in thin targets is considered. The targets not thinner than about 10 $$\upmu $$ μ m are discussed. The analogue of the Landau distribution function is derived for this loss under the condition when the Chudakov effect of the pair ionization loss suppression is manifested. Expression for the most probable value of the pair ionization loss $$E_{MP}$$ E MP is obtained. It is shown that the magnitude of Chudakov effect for $$E_{MP}$$ E MP can be noticeably different from the magnitude of this effect for the restricted mean value of the pair ionization loss.

Determination of Ionization Energy Loss of Electron-Positron Pair in Multi-GeV Region

“…More recently, Trofymenko determined the struggling function for the most probable value of the pair ionization loss, which includes the Chudakov effect (Trofymenko, 2023). The theoretical results of this study can be used to adopt the Chudakov effect in the simulation packages used for high energy physics experiments such as GEANT4 (Agostinelli, et al, 2003).…”

“…However, the expected relative energy deposition of the pairs can be used to derive the energy loss distribution of the pairs. Recently, Trofymenko proposed the struggling function for the most probable value of the pair ionization loss, which includes the effect of ionization suppression (Trofymenko, 2023). It is stated that the most probable value of the ionization loss of 𝑒 − -𝑒 + pairs can be written as (Trofymenko, 2023).…”

“…Recently, Trofymenko proposed the struggling function for the most probable value of the pair ionization loss, which includes the effect of ionization suppression (Trofymenko, 2023). It is stated that the most probable value of the ionization loss of 𝑒 − -𝑒 + pairs can be written as (Trofymenko, 2023). This expression fit in the struggling function given in (Trofymenko, 2023) and can be used to determine the relative suppression.…”

“…It is stated that the most probable value of the ionization loss of 𝑒 − -𝑒 + pairs can be written as (Trofymenko, 2023). This expression fit in the struggling function given in (Trofymenko, 2023) and can be used to determine the relative suppression. Thus, the ratio of the most probable energy loss (MPEL) of the pairs can be written as 𝐸 𝑀𝑃 (𝑠 1 ) 𝐸 𝑀𝑃 (𝑠 2 ) ⁄ .…”

“…Although equation 4 mostly coincides with the experimental data (Virkus, et al, 2008) at the high energy region, the difference between curves below 10 GeV is still present. However, the R values can be used to simulate the expected energy deposition distributions for the energies below 40 GeV where 𝐸 𝑀𝑃 (𝑠 2 ) is almost constant (Trofymenko, 2023). The expected distributions with ionization suppression were determined by applying the R values to the energy depositions of the pairs formed by photon sources with 11.8 and 37.2 GeV energies and are given in Figure 5.…”