Monte Carlo simulations of the rates in the forward endcap.

Performed with DPM at 15 GeV/c momentum for 10^7 antiprotons per second.

Done by Torsten Schroeder October 2012.

Crystal position	no threshold		above 0 MeV		above 1 MeV		above 3 MeV		above 10 MeV
	rate/s	<E>	rate/s	<E>	rate/s	<E>	rate/s	<E>	rate/s	<E>
2nd xtal next to hole (VPTT)	10^7	4.2 MeV	1.1 10^6	35.8 MeV	533 10^3	77 MeV	330 10^3	123 MeV	210 10^3	188 MeV
highest rate APD	10^7	0.5 MeV	410 10^3	12.9 MeV	160 10^3	33 MeV	88 10^3	58 MeV	48 10^3	102 MeV

-- FritzHerbertHeinsius - 29 Aug 2014

Monte Carlo simulations of the radiation dose of APDs for the forward endcap.

Done by Bernhard Roth (RUB) Oktober 2012. Assumptions: APD of 200 um Si behind the crystals. Beam momentum of 15 GeV/c. Luminosity of 2*10^32 cm^-2s^-1. 10 half years data taking. Please note, that this is the peak luminosity. The average luminosity is a factor of 2 lower. So all values of the table below have to be divided by 2.

Theta [deg]	Rate [mGy/h]	Dose [Gy]	APD hits [1E10]
5.78	10.48	459.02	131.86
7.13	7.17	314.04	83.54
8.46	4.69	205.44	56.61
9.80	3.34	146.49	40.77
11.11	2.16	94.72	29.42
12.44	1.85	81.14	22.55
13.72	1.31	57.50	16.91
15.03	1.02	44.88	13.82
16.29	0.81	35.65	10.53
17.58	0.73	31.81	8.91
18.80	0.50	22.09	6.75
20.07	0.39	17.03	5.18
21.26	0.29	12.60	3.55
22.50	0.18	8.05	2.23

APDs are used up to theta of 14.4 degree. In the inner regions VPTT are foreseen.

Taking into account the average luminosity of 1*10^32 cm^-2s^-1 and the range of APDs from 22.5 to 14.4 degrees results in a lifetime dose of 4 Gy to 26 Gy.

For more details please check this document: bernhardDoseStudy.pdf (Radiation study by Bernhard Roth (RUB))

Monte Carlo simulations of the dose in the forward endcap (page 17), indico login required:

https://indico.gsi.de/getFile.py/access?contribId=5&sessionId=0&resId=0&materialId=slides&confId=4582

-- FritzHerbertHeinsius - 08 Jan 2021