Lifetimes of doubly charmed baryons

Cheng, HY, Shi, YL (December 2018) Lifetimes of doubly charmed baryons. Physical Review D, 98 (11). ISSN 2470-0010

[thumbnail of 10.1103.PhysRevD.98.113005.pdf]
Preview
PDF
10.1103.PhysRevD.98.113005.pdf - Published Version
Available under License Creative Commons Attribution.

Download (271kB) | Preview

Abstract

The lifetimes of doubly charmed hadrons are analyzed within the framework of the heavy quark expansion (HQE). Lifetime differences arise from spectator effects such as W-exchange and Pauli interference. The Ξcc++ baryon is longest-lived in the doubly charmed baryon system owing to the destructive Pauli interference absent in the Ξcc+ and Ωcc+. In the presence of dimension-seven contributions, its lifetime is reduced from ∼5.2×10-13 s to ∼3.0×10-13 s. The Ξcc+ baryon has the shortest lifetime of order 0.45×10-13 s due to a large contribution from the W-exchange box diagram. It is difficult to make a precise quantitative statement on the lifetime of Ωcc+. Contrary to Ξcc baryons, τ(Ωcc+) becomes longer in the presence of dimension-seven effects and the Pauli interference Γ+int even becomes negative. This implies that the subleading corrections are too large to justify the validity of the HQE. Demanding the rate Γ+int to be positive for a sensible HQE, we conjecture that the Ωc0 lifetime lies in the range of (0.75∼1.80)×10-13 s. The lifetime hierarchy pattern is τ(Ξcc++)>τ(Ωcc+)>τ(Ξcc+) and the lifetime ratio τ(Ξcc++)/τ(Ξcc+) is predicted to be of order 6.7.

Item Type: Paper
CSHL Authors:
Communities: CSHL labs > Engel lab
SWORD Depositor: CSHL Elements
Depositing User: CSHL Elements
Date: 1 December 2018
Date Deposited: 11 Sep 2024 17:41
Last Modified: 11 Sep 2024 17:41
Related URLs:
URI: https://repository.cshl.edu/id/eprint/41658

Actions (login required)

Administrator's edit/view item Administrator's edit/view item