There are a number of pre-set reaction regions. These do not automatically set the reaction type, so don't expect aluminum exit window simulations by setting reaction region to 3...

• 1: LH2 Target
• 2: front entrance window
• 3: back exit window
• 4: Dummy Target (1% US Al)
• 5: Dummy Target (2% US Al)
• 6: Dummy Target (4% US Al)
• 7: Dummy Target (2% DS Al)
• 8: Dummy Target (4% DS Al)
• 9: Dummy Target (8% DS Al)
• 10: Dummy Target (US Carbon)
• 11: Dummy Target (DS Carbon)
• else: target