Hacker news

  • Top
  • New
  • Past
  • Ask
  • Show
  • Jobs

Observation of the doubly charmed heavy proton Ξcc+ (https://lhcb-outreach.web.cern.ch)

52 points by nobody9999 4 days ago | 8 comments | View on ycombinator

ars 3 days ago |

This is significant because binding 2 heavy quarks together is very hard to do because they decay so fast.

All the particles made from just 3 light quarks have been found. And I think all of the ones made with 1 heavy quark and 2 light ones have also been found.

This is only the 2nd particle made from 2 heavy quarks that has ever been found.

It's not a coincidence that both of those were made with charm quarks, because charm quarks are the lightest of the heavy ones.

None made of 3 heavy quarks has been found (yet).

Also: A particle made with a top quark is not possible - it decays too quickly.

steve_gh 3 days ago |

Are there are other flavours of proton still to be discovered? Can you (theoretically) build a proton with any two quarks selected from {up, charm, top} and one selected from {down, strange, bottom}?