In this work, we study the nonleptonic decays $$\Xi _{cc}^{++}\rightarrow \Xi _{c}^{(\prime )+}\pi ^{+}$$ with considering $$\Xi _{c}-\Xi _{c}^{\prime }$$ mixing. The relevant decay amplitudes are evaluated within the framework of nonrelativistic quark model, combining the baryon spatial wave functions adopted from solving the Schrödinger equation with a nonrelativistic potential. With the mixing angle ranging $$\theta \in (-18.2^{\circ },-14.3^{\circ }),$$ we successfully reproduce the measured ratio $$R={\mathcal {B}}[\Xi _{cc}^{++}\rightarrow \Xi _{c}^{\prime +}\pi ^{+}]/{\mathcal {B}}[\Xi _{cc}^{++}\rightarrow \Xi _{c}^{+}\pi ^{+}]$$ reported by the LHCb Collaboration. Furthermore, we estimate the branching fractions as $${\mathcal {B}}[\Xi _{cc}^{++}\rightarrow \Xi _{c}^{+}\pi ^{+}]=(3.2\sim 4.3)\%$$ and $${\mathcal {B}}[\Xi _{cc}^{++}\rightarrow \Xi _{c}^{\prime +}\pi ^{+}]=(4.2\sim 6.0)\%,$$ and the asymmetry parameters as $$\alpha [\Xi _{cc}^{++}\rightarrow \Xi _{c}^{+}\pi ^{+}]=(-0.80\sim -0.81)$$ and $$\alpha [\Xi _{cc}^{++}\rightarrow \Xi _{c}^{\prime +}\pi ^{+}]=(-0.61\sim -0.62).$$ The measurements of absolute branching fractions and asymmetry parameters by the ongoing LHCb and Belle II experiments will be helpful for further testing our numerical results and confirming the mixing angle.

China

Yu-Shuai Li

The nonleptonic decays $$\Xi _{cc}^{++}\rightarrow \Xi _{c}^{(\prime )+}\pi ^{+}$$ within the nonrelativistic quark model

Using 983.0 fb and 427.9 fb data samples collected with the Belle and Belle II detectors at the KEKB and SuperKEKB asymmetric energy $\textit{e}$ $\textit{e}$ colliders, respectively, we present studies of the Cabibbo-favored $${\Xi }_{c}^{+}$$ decays $${\Xi }_{c}^{+}\to {\Sigma }^{+}{K}_{S}^{0}$$ and $${\Xi }_{c}^{+}\to {\Xi }^{0}{\pi }^{+}$$ , and the singly Cabibbo-suppressed decay $${\Xi }_{c}^{+}\to {\Xi }^{0}{K}^{+}$$ . The ratios of branching fractions of $${\Xi }_{c}^{+}\to {\Sigma }^{+}{K}_{S}^{0}$$ and $${\Xi }_{c}^{+}\to {\Xi }^{0}{K}^{+}$$ relative to that of $${\Xi }_{c}^{+}\to {\Xi }^{-}{\pi }^{+}{\pi }^{+}$$ are measured for the first time, while the ratio $$\mathcal{B}({\Xi }_{c}^{+}\to {\Xi }^{0}{\pi }^{+})/\mathcal{B}({\Xi }_{c}^{+}\to {\Xi }^{-}{\pi }^{+}{\pi }^{+})$$ is also determined and improved by an order of magnitude in precision. The measured branching fraction ratios are

I. Adachi

J. Ahn

Y. Ahn

N. Akopov

S. Alghamdi

M. Alhakami

N. Althubiti

K. Amos

N. Anh Ky

C. Antonioli

D. Asner

M. Aversano

R. Ayad

V. Babu

N. Baghel

P. Bambade

Sw. Banerjee

M. Barrett

M. Bartl

J. Baudot

A. Beaubien

F. Becherer

J. Becker

J. Bennett

V. Bertacchi

M. Bertemes

E. Bertholet

M. Bessner

S. Bettarini

B. Bhuyan

F. Bianchi

D. Biswas

D. Bodrov

A. Bondar

G. Bonvicini

A. Boschetti

A. Bozek

M. Bračko

P. Branchini

R. Briere

A. Budano

S. Bussino

Q. Campagna

M. Campajola

L. Cao

G. Casarosa

C. Cecchi

M.C. Chang

P. Cheema

B. Cheon

K. Chilikin

J. Chin

K. Chirapatpimol

H.E. Cho

K. Cho

S.J. Cho

S.K. Choi

S. Choudhury

J. Cochran

I. Consigny

L. Corona

J. Cui

E. Cruz-Burelo

S. Motte

G. Pietro

R. Sangro

M. Destefanis

S. Dey

A. Canto

J. Dingfelder

Z. Doležal

I. Domínguez Jiménez

T. Dong

M. Dorigo

G. Dujany

P. Ecker

P. Feichtinger

T. Ferber

T. Fillinger

C. Finck

G. Finocchiaro

A. Fodor

F. Forti

B. Fulsom

A. Gabrielli

A. Gale

M. Garcia-Hernandez

R. Garg

G. Gaudino

V. Gaur

V. Gautam

A. Gaz

A. Gellrich

D. Ghosh

H. Ghumaryan

R. Giordano

A. Giri

P. Gironella Gironell

A. Glazov

B. Gobbo

Measurements of the branching fractions of $${\Xi }_{c}^{+}\to {\Sigma }^{+}{K}_{S}^{0}$$ , $${\Xi }_{c}^{+}\to {\Xi }^{0}{\pi }^{+}$$ , and $${\Xi }_{c}^{+}\to {\Xi }^{0}{K}+$$ at Belle and Belle II

Using a sample of (2$\textit{.}$712 ± 0$\textit{.}$014) × 10 $\textit{ψ}$(3686) events collected with the BESIII detector at the electron positron collider BEPCII, the decay $\textit{ψ}$(3686) → $$ {\Xi}^{-}{K}_S^0{\overline{\varOmega}}^{+} $$ + $\textit{c.c.}$ is observed for the first time, which has a significance of 5.9 standard deviations. The branching fraction of this decay is measured to be (2$\textit{.}$91 ± 0$\textit{.}$47 ± 0$\textit{.}$33) × 10 , where the first and second uncertainties are statistical and systematic, respectively. The ratio between $$ {\mathcal{B}}_{\psi (3686)\to {\varXi}^{-}{K}_S^0{\overline{\varOmega}}^{+}+c.c} $$ and $$ {\mathcal{B}}_{\psi (3686)\to {\varOmega}^{-}{K}^{+}{\overline{\Xi}}^0+c.c} $$ is determined to be 1$\textit{.}$05 ± 0$\textit{.}$23 ± 0$\textit{.}$14, which deviates from the isospin symmetry conservation predicted value of 0.5 by 2$\textit{.}$1$\textit{σ}$.

M. Ablikim

Russia

M. Achasov

Sweden

P. Adlarson

X. Ai

Germany

R. Aliberti

Italy

A. Amoroso

Q. An

Y. Bai

O. Bakina

Y. Ban

H.R. Bao

Poland

V. Batozskaya

Mongolia

K. Begzsuren

N. Berger

M. Berlowski

M. Bertani

D. Bettoni

E. Bianco

A. Bortone

I. Boyko

United States

A. Brueggemann

H. Cai

M. Cai

X. Cai

A. Calcaterra

G. Cao

N. Cao

Türkiye

S. Cetin

X. Chai

J. Chang

G. Che

Y. Che

G. Chelkov

C. Chen

Chao Chen

G. Chen

H. Chen

M. Chen

S. Chen

T. Chen

X. Chen

Y. Chen

Z. Chen

South Korea

S. Choi

X. Chu

G. Cibinetto

F. Cossio

H. Dai

J. Dai

A. Dbeyssi

R. Boer

D. Dedovich

C. Deng

Z. Deng

A. Denig

I. Denysenko

F. Mori

B. Ding

X. Ding

Y. Ding

J. Dong

L. Dong

M. Dong

X. Dong

M. Du

S. Du

Y. Duan

Z. Duan

P. Egorov

G. Fan

J. Fan

Y. Fan

J. Fang

S. Fang

W. Fang

Y. Fang

R. Farinelli

L. Fava

F. Feldbauer

G. Felici

C. Feng

J. Feng

Y. Feng

M. Fritsch

C. Fu

Observation of $\textit{ψ}$(3686) $\textit{→}$ $$ {\Xi}^{-}{K}_S^0{\overline{\varOmega}}^{+} $$ + c.c.