Re:LHCb announces a charming new particle
by mmusson on Thursday July 06, 2017 @07:36PM
(#14714853)
Ξ++
cc or double charmed Xi.
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Re:LHCb announces a charming new particle
by _asummers on Thursday July 06, 2017 @08:30PM
(#14715082)
That's neat. I see the Xi. Does the ++ mean double, and the cc mean charmed? Having trouble parsing that, even with the sub and superscripts from the article. I guess more concretely, would a triple charmed (if that means anything) be +++ cc or ++ ccc?
There are constraints on how quarks combine, according to the standard model, which mean (among other things) that you won't get three of the same quark combining to form a particle. The cc subscript indicates the presences of two charm quarks, and the ++ indicates the particle has an electric charge Q=+2. The subscript values show the presence of heavy quarks: charm (c), bottom (b) or top (t) quarks are heavy. The superscript is electric charge (Q), a value between -1 and +2 (-, 0, +, or ++).