What is this notation? I haven't seen it before

Tags:
1. Aug 29, 2015

Alucard

X5(p,α)X6

This is an equation/part of a question in my nuclear physics unit, where X5 represents the reactant nucleus and X6 is the product nucleus. The alpha symbol is most likely alpha decay, but I have no idea what it means in conjunction with 'p' like that. The rest of the question is:
In the carbon cycle that occurs on the Sun, He-4 is built from four protons and
C-12. First, C-12 absorbs a proton to form a nucleus, X1. Then X1 decays by
positron emission to X2, which then absorbs a proton to become X3, which itself
absorbs a proton to become X4. X4 then decays to X5 by positron decay and X5
reacts via: X5(p,α)X6

It's from the Walding Physics textbook if anyone has it.

2. Aug 29, 2015

SteamKing

Staff Emeritus
It's a shorthand form for a nuclear reaction. There's an explanation here on page 2:

http://oregonstate.edu/instruct/ch374/ch418518/Chapter 10 NUCLEAR REACTIONS.pdf

It's basically T (P,x) R which is short for:

Target nucleus + Projectile → x (emitted particle) + Residual nucleus

3. Aug 29, 2015

Alucard

4. Aug 30, 2015

mathman

X5 + proton -> alpha particle + X6