Questions on magnetic moments

[Rade]

I read at this link to Lawrence Berkeley National Laboratory,

 

http://www.lbl.gov/abc/Antimatter.html

 

that the magnetic moments of both the antielectron (positron) and antiproton have opposite signs of their matter counterparts (the electron and proton). My first question is, would the same then be true for the antineutron, given that it has neutral change as matter neutron ?

 

Second question, suppose you have two particles, one of 3 mass units and being matter, and the other of 2 mass units and being antimatter. When these two particles meet, would it be expected that the magnetic moments would both shift signs, so a (+) would become a (-) and a (-) would become a (+) ? Note that because the two particles have different masses there is no reason to expect complete annihilation when they meet. I know that interactions between matter and antimatter of different mass units are not well known, just hoping someone has some thoughts on the questions asked.

[UncleAl]

An elementary particle's magnetic moment direction arises from its sense of spin. A negative value says magnetic moment is antiparallel to spin. An antineutron is charge (its constituent quarks) and parity reversed compared to a matter neutron. Its magnetic moment is reversed in sign.

 

Is there conservation of magnetic moment? Consider the spontaneous decay of a triplet (two parallel 1/2 spins) to a singlet (zero net spin) state, like ortho- to para-hydrogen with the emission of a 21 cm microwave photon. (The Bohr and nuclear magnetons differ in size by a factor of ~1800.) Photons have zero magnetic moment (close enough, [hep-th/0609008] Has the Photon an Anomalous Magnetic Moment?). While the transition is strongly forbidden, it still occurs (half-life of about 3.4857x10^14 seconds in collisionless vacuum).

[Rade]

Thanks Dr. Al,

 

So, both the proton [P] and neutron [N] have reversed magnetic moments (in sign) compared to antimatter proton and antimatter neutron.

 

I have another question. The magnetic moment of the deuteron [NP] is +0.8574376 nuc. magnetons. I assume this then means that the antideuteron would have a reversed magnetic moment of -0.8574376--would this be correct ?

[UncleAl]

Uncle Al is an organic chemist. If you want expert commentary on antimatter you need an appropriate physicist. General rule of thumb, inversion of matter to antimatter inverts observables. However... processes are not properties. The Weak interaction is strictly left-handed.

 

Physics desperately wishes to isolate anti-hydrogen atoms to observe how they vacuum free fall (gravitation and antimatter) and their Lamb shift (quantum mechanics and antimatter).