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Q & A: Why is a glueball unstable?

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Most recent answer: 12/11/2013
Why is a glueball unstable? If a glueball is made of three(?) gluons and is "color charge neutral as a whole", these gluons should stick together and be stable? But it is not stable, I heard. why?
- Anonymous

Hi Anything,

As you point out glueballs would be made of strongly interacting gluons.  As such, the constituents would interact freely with other strongly interacting particles and if energetically favorable would cheerfully decay into them.   A variety of predictions have been made of the glueballs mass and most of them come out in the one to two Gev region with a rather broad width.   So they would probably decay into a bunch of pions.    In order to claim a discovery you would have to observe a rather broad mass bump hidden in a spectrum of final states observed at colliders like the LHC.  This is a bit tricky when you have lots of accompanying junk in the final state.  Nevertheless, people have looked but no glueballs yet,    

There is a proposal, see  ,   to use the electron accelerator at JLAB to search for these bags of gluons.   We will have to wait a bit untill they get going.




(published on 12/11/2013)

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