Mesons and bosons, same or different?

1. Oct 8, 2007

doubledouble

Mesons are bosons, but are all bosons mesons e.g. intermediate vector bosons (w and z bosons in the weak interaction)?

2. Oct 8, 2007

Norman

No, not all bosons are mesons.

meson:
Any of a family of subatomic particles that participate in strong interactions, are composed of a quark and an antiquark (or a QM linear combination of quark + antiquark combos), and have masses generally intermediate between leptons and baryons.

boson:
Any particle (or composite system) which has a total spin quantum number that is an integer (0,1,2,...) and therefore obeys Bose-Einstein statistics for its quantum state.

3. Oct 8, 2007

mathman

Photons, gluons, and gravitons are bosons, but none of them are mesons. Also all atoms with an even number of neutrons are bosons.

4. Oct 8, 2007

CarlB

"Also all atoms with an even number of neutrons are bosons."

Actually, the hydrogen atom has zero neutrons, but is a boson. For example see:
http://focus.aps.org/story/v2/st22

The hydrogen nucleus, on the other hand, is a fermion. The deuterium atom, which has a neutron, a proton, and an electron, is a fermion. A given atom will alternate between being a boson and a fermion as you strip electrons off of it. This is cause electrons are fermions and have to be counted along with the neutrons and protons in the nucleus. The nucleus for a given atom will always be a boson or fermion. See wikipedia:

http://en.wikipedia.org/wiki/Boson#Composite_bosons

5. Oct 9, 2007

malawi_glenn

"Also all atoms with an even number of neutrons are bosons"

He hust have meant "even number of nucleons";
since all even-even nucleis have total Angular momentum J = 0

6. Oct 9, 2007

Norman

actually he did mean "even number of neutrons" cause as has been said, in an atom (key word here- neutral atom is assumed) you count the electrons, neutrons and protons.

A neutral atom always has # electrons = # protons. This always yields an even number. So atoms with even numbers of neutrons PLUS the hydrogen atom are bosons.

I don't know if zero is considered an even integer or not. It has been a long time since I have taken a formal math course.

7. Oct 9, 2007

mathman

0 is an even number. It certainly is not odd, so be all usual rules of arithmetic, it is even.

The usual definition is a number is even if there is no remainder when divided by 2.