双粲重子Ξ⁺(cc)的首次观测。

First observation of the doubly charmed baryon Xi(+)(cc).

作者信息

Mattson M, Alkhazov G, Atamantchouk A G, Balatz M Y, Bondar N F, Cooper P S, Dauwe L J, Davidenko G V, Dersch U, Dolgolenko A G, Dzyubenko G B, Edelstein R, Emediato L, Endler A M F, Engelfried J, Eschrich I, Escobar C O, Evdokimov A V, Filimonov I S, Garcia F G, Gaspero M, Giller I, Golovtsov V L, Gouffon P, Gülmez E, Kangling He, Iori M, Jun S Y, Kaya M, Kilmer J, Kim V T, Kochenda L M, Konorov I, Kozhevnikov A P, Krivshich A G, Krüger H, Kubantsev M A, Kubarovsky V P, Kulyavtsev A I, Kuropatkin N P, Kurshetsov V F, Kushnirenko A, Kwan S, Lach J, Lamberto A, Landsberg L G, Larin I, Leikin E M, Yunshan Li, Luksys M, Lungov T, Maleev V P, Mao D, Chensheng Mao, Zhenlin Mao, Mathew P, Matveev V, McCliment E, Moinester M A, Molchanov V V, Morelos A, Nelson K D, Nemitkin A V, Neoustroev P V, Newsom C, Nilov A P, Nurushev S B, Ocherashvili A, Oliveira E, Onel Y, Ozel E, Ozkorucuklu S, Penzo A, Petrenko S V, Pogodin P, Procario M, Prutskoi V A, Ramberg E, Rappazzo G F, Razmyslovich B V, Rud V I, Russ J, Schiavon P, Simon J, Sitnikov A I, Skow D, Smith V J, Srivastava M, Steiner V, Stepanov V, Stutte L, Svoiski M, Terentyev N K, Thomas G P, Uvarov L N, Vasiliev A N, Vavilov D V, Verebryusov V S, Victorov V A, Vishnyakov V E, Vorobyov A A, Vorwalter K, You J, Wenheng Zhao, Shuchen Zheng, Zukanovich-Funchal R

机构信息

Carnegie-Mellon University, Pittsburgh, Pennsylvania 15213, USA.

出版信息

Phys Rev Lett. 2002 Sep 9;89(11):112001. doi: 10.1103/PhysRevLett.89.112001. Epub 2002 Aug 20.

DOI:10.1103/PhysRevLett.89.112001

PMID:12225136

Abstract

We observe a signal for the doubly charmed baryon Xi(+)(cc) in the charged decay mode Xi(+)(cc)-->Lambda(+)(c)K-pi(+) in data from SELEX, the charm hadroproduction experiment at Fermilab. We observe an excess of 15.9 events over an expected background of 6.1+/-0.5 events, a statistical significance of 6.3sigma. The observed mass of this state is 3519+/-1 MeV/c(2). The Gaussian mass width of this state is 3 MeV/c(2), consistent with resolution; its lifetime is less than 33 fs at 90% confidence.

摘要

我们在费米实验室的魅夸克强子产生实验SELEX的数据中，观察到双魅重子Ξ⁺(cc)在带电衰变模式Ξ⁺(cc)→Λ⁺(c)K⁻π⁺下的一个信号。我们观察到在预期本底6.1±0.5个事例之上有15.9个事例的超出，统计显著性为6.3σ。这个态的观测质量为3519±1 MeV/c²。这个态的高斯质量宽度为3 MeV/c²，与分辨率相符；其寿命在90%置信度下小于33飞秒。