| Classification | Hadron Baryon |
|---|---|
| Statistics | Fermion |
| Mass | 3621.4 MeV/c2 |
| Mean lifetime | between 5.0×10−14 and 1.0×10−12 |
The Xi double-charm baryon, denoted as , is a Xi baryon composed of two charm quarks and one up quark.
Its discovery by the LHCb Collaboration was announced on 6 July 2017 in Venice, Italy, at the European Physical Society Conference on High Energy Physics. is the first baryon discovered with two heavy quarks (charm and/or bottom) and a light quark. Its mass is 3621 MeV/c2, nearly four times that of the proton.
It was identified when it disintegrated into a baryon and three lighter mesons, K–, π+ and π+.