A study of the charmless baryonic decays $$ {B}_{(s)}^0\to {K}^0p\overline{p} $$ is presented, where $$ {B}_{(s)}^0 $$ denotes either a $\textit{B}$ or a $$ {B}_s^0 $$ meson. The analysis is based on proton-proton collision data collected by the LHCb experiment at centre-of-mass energies of 7, 8, and 13 TeV, corresponding to an integrated luminosity of 9 fb . The decay $$ {B}_s^0\to {K}^0p\overline{p} $$ is observed for the first time, with a measured branching fraction of (9$\textit{.}$14 $\textit{±}$ 1$\textit{.}$69 $\textit{±}$ 0$\textit{.}$90 $\textit{±}$ 0$\textit{.}$33 $\textit{±}$ 0$\textit{.}$20) $\textit{×}$ 10 and a significance of 5.6$\textit{σ}$. The uncertainties respectively account for statistical and systematic contributions, the precision of the branching fraction of the normalisation channel $\textit{B}$ $\textit{→ K}$ $\textit{π}$ $\textit{π}$ and the fragmentation fraction ratio $\textit{f}$ $\textit{/f}$ . The branching fraction determined for $$ {B}^0\to {K}^0p\overline{p} $$ is (2$\textit{.}$82 $\textit{±}$ 0$\textit{.}$08 $\textit{±}$ 0$\textit{.}$12 $\textit{±}$ 0$\textit{.}$10) $\textit{×}$ 10 , which is the most precise measurement to date.

Netherlands

R. Aaij

United Kingdom

A. Abdelmotteleb

Switzerland

C. Abellan Beteta

F. Abudinén

T. Ackernley

United States

A. Adefisoye

Spain

B. Adeva

M. Adinolfi

Sweden

P. Adlarson

France

C. Agapopoulou

C. Aidala

Z. Ajaltouni

S. Akar

K. Akiba

Italy

P. Albicocco

Germany

J. Albrecht

F. Alessio

Z. Aliouche

P. Alvarez Cartelle

R. Amalric

Brazil

S. Amato

J. Amey

Y. Amhis

China

L. An

L. Anderlini

M. Andersson

A. Andreianov

P. Andreola

M. Andreotti

D. Andreou

A. Anelli

D. Ao

F. Archilli

M. Argenton

Costa Rica

S. Arguedas Cuendis

A. Artamonov

M. Artuso

E. Aslanides

R. Ataíde Da Silva

M. Atzeni

B. Audurier

D. Bacher

I. Bachiller Perea

S. Bachmann

M. Bachmayer

J. Back

P. Baladron Rodriguez

V. Balagura

A. Balboni

W. Baldini

L. Balzani

H. Bao

J. Baptista de Souza Leite

C. Barbero Pretel

M. Barbetti

I. Barbosa

R. Barlow

M. Barnyakov

S. Barsuk

W. Barter

J. Bartz

Poland

S. Bashir

B. Batsukh

P. Battista

A. Bay

A. Beck

M. Becker

F. Bedeschi

I. Bediaga

N. Behling

S. Belin

K. Belous

I. Belov

I. Belyaev

G. Benane

G. Bencivenni

E. Ben-Haim

A. Berezhnoy

R. Bernet

S. Bernet Andres

A. Bertolin

C. Betancourt

F. Betti

J. Bex

Ia. Bezshyiko

Ukraine

O. Bezshyyko

J. Bhom

M. Bieker

N. Biesuz

P. Billoir

A. Biolchini

M. Birch

F. Bishop

A. Bitadze

A. Bizzeti

T. Blake

F. Blanc

J. Blank

S. Blusk

V. Bocharnikov

Observation of the decay $$ {B}_s^0\to {K}^0p\overline{p} $$ and measurement of the $$ {B}_{(s)}^0\to {K}^0p\overline{p} $$ branching fractions

Addressing the fermion flavor structures using modular invariance is a challenging task in the framework of quark-lepton unification. Building on recent applications of modular symmetry in nonsupersymmetric models, we propose the first renormalizable <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>S</mi><mi>U</mi><mo stretchy="false">(</mo><mn>5</mn><mo stretchy="false">)</mo></math> grand unified theory incorporating level 3 nonholomorphic modular symmetry, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi mathvariant="normal">Γ</mi><mn>3</mn></msub><mo>≃</mo><msub><mi>A</mi><mn>4</mn></msub></math>. This framework constrains Yukawa couplings to polyharmonic Maaß forms, significantly reducing the number of free parameters while enhancing the predictive power of the models. We present a comprehensive analysis of fermion masses and mixing while tackling key grand unified theory (GUT) queries such as gauge coupling unification and proton decay. Beyond the minimal <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>S</mi><mi>U</mi><mo stretchy="false">(</mo><mn>5</mn><mo stretchy="false">)</mo></math> framework, the Higgs sector incorporates the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>4</mn><msub><mn>5</mn><mi>H</mi></msub></math> dimensional Higgs field crucial in differentiating the masses of down quarks and charged leptons, and the fermion sector is extended with three right-handed neutrinos enabling neutrino masses via the type-I seesaw mechanism. We analyze two benchmark models with distinct modular weight and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>A</mi><mn>4</mn></msub></math> charge assignments. The predicted effective Majorana mass <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>m</mi><mrow><mi>β</mi><mi>β</mi></mrow></msub></math> values align with current neutrinoless double-beta decay experiments, and the effective neutrino mass <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>m</mi><mi>β</mi></msub></math> is within the reach of future beta decay searches. The predicted sum of neutrino masses, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo>∑</mo><msub><mi>m</mi><mi>i</mi></msub></math>, satisfies the upper bound set by recent cosmological observations. The gauge coupling unification is achieved through a light scalar triplet <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>ϕ</mi><mn>3</mn></msub><mo>∼</mo><mo stretchy="false">(</mo><mn>3</mn><mo>,</mo><mn>3</mn><mo>,</mo><mo>−</mo><mn>1</mn><mo>/</mo><mn>3</mn><mo stretchy="false">)</mo></math> and a scalar octet <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>ϕ</mi><mn>5</mn></msub><mo>∼</mo><mo stretchy="false">(</mo><mn>8</mn><mo>,</mo><mn>2</mn><mo>,</mo><mn>1</mn><mo>/</mo><mn>2</mn><mo stretchy="false">)</mo></math> belonging to the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>4</mn><msub><mn>5</mn><mi>H</mi></msub></math> Higgs, while proton decay constraints require that the contribution of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>4</mn><msub><mn>5</mn><mi>H</mi></msub></math> Higgs to the up-quark mass matrix remains highly suppressed.

United Arab Emirates

Mohamed Amin Loualidi

Morocco

Mohamed Miskaoui

Salah Nasri

Nonholomorphic <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>A</mi><mn>4</mn></msub></math> modular invariance for fermion masses and mixing in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>S</mi><mi>U</mi><mo stretchy="false">(</mo><mn>5</mn><mo stretchy="false">)</mo></math> GUT

The first evidence for the decay <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mi>B</mi></mrow><mrow><mo>−</mo></mrow></msup><mo stretchy="false">→</mo><msup><mrow><mi>D</mi></mrow><mrow><mo>*</mo><mo>*</mo><mn>0</mn></mrow></msup><msup><mrow><mi>τ</mi></mrow><mrow><mo>−</mo></mrow></msup><msub><mrow><mover accent="true"><mrow><mi>ν</mi></mrow><mrow><mo stretchy="true">¯</mo></mrow></mover></mrow><mrow><mi>τ</mi></mrow></msub></mrow></math> is obtained using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>9</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>, at centre-of-mass energies of 7, 8, and 13 TeV. Here, the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mrow><mo>*</mo><mo>*</mo><mn>0</mn></mrow></msup></math> meson represents any of the three excited charm mesons <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>D</mi><mn>1</mn></msub><mo stretchy="false">(</mo><mn>2420</mn><msup><mo stretchy="false">)</mo><mn>0</mn></msup></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>D</mi><mn>2</mn><mo>*</mo></msubsup><mo stretchy="false">(</mo><mn>2460</mn><msup><mo stretchy="false">)</mo><mn>0</mn></msup></math>, and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>D</mi><mn>1</mn><mo>′</mo></msubsup><mo stretchy="false">(</mo><mn>2400</mn><msup><mo stretchy="false">)</mo><mn>0</mn></msup></math>. The <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mo>−</mo></msup><mo stretchy="false">→</mo><mrow><msup><mi>D</mi><mrow><mo>*</mo><mo>*</mo><mn>0</mn></mrow></msup><msup><mi>τ</mi><mo>−</mo></msup><msub><mover accent="true"><mi>ν</mi><mo stretchy="false">¯</mo></mover><mi>τ</mi></msub></mrow></math> signal is measured with a significance of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>3.5</mn><mi>σ</mi></math>, including systematic uncertainties. The combined branching fraction <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi mathvariant="script">B</mi><mo stretchy="false">(</mo><msup><mrow><mi>B</mi></mrow><mrow><mo>−</mo></mrow></msup><mo stretchy="false">→</mo><msubsup><mrow><mi>D</mi></mrow><mrow><mn>1</mn><mo>,</mo><mn>2</mn></mrow><mrow><mo>*</mo><mo>*</mo><mn>0</mn></mrow></msubsup><msup><mrow><mi>τ</mi></mrow><mrow><mo>−</mo></mrow></msup><msub><mrow><mover accent="true"><mrow><mi>ν</mi></mrow><mrow><mo stretchy="false">¯</mo></mrow></mover></mrow><mrow><mi>τ</mi></mrow></msub><mo stretchy="false">)</mo><mo>×</mo><mi mathvariant="script">B</mi><mo stretchy="false">(</mo><msubsup><mrow><mi>D</mi></mrow><mrow><mn>1</mn><mo>,</mo><mn>2</mn></mrow><mrow><mo>*</mo><mo>*</mo><mn>0</mn></mrow></msubsup><mo stretchy="false">→</mo><msup><mrow><mi>D</mi></mrow><mrow><mo>*</mo><mo>+</mo></mrow></msup><msup><mrow><mi>π</mi></mrow><mrow><mo>−</mo></mrow></msup><mo stretchy="false">)</mo></mrow></math>, where <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>D</mi><mrow><mn>1</mn><mo>,</mo><mn>2</mn></mrow><mrow><mo>*</mo><mo>*</mo><mn>0</mn></mrow></msubsup></math> denotes both <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>D</mi><mn>1</mn></msub><mo stretchy="false">(</mo><mn>2420</mn><msup><mo stretchy="false">)</mo><mn>0</mn></msup></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>D</mi><mn>2</mn><mo>*</mo></msubsup><mo stretchy="false">(</mo><mn>2460</mn><msup><mo stretchy="false">)</mo><mn>0</mn></msup></math> contributions, is measured to be <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mo stretchy="false">[</mo><mn>0.051</mn><mo>±</mo><mn>0.013</mn><mrow><mo stretchy="false">(</mo><mi>stat</mi><mo stretchy="false">)</mo></mrow><mo>±</mo><mn>0.006</mn><mrow><mo stretchy="false">(</mo><mi>syst</mi><mo stretchy="false">)</mo></mrow><mo>±</mo><mn>0.009</mn><mo stretchy="false">(</mo><mi>ext</mi><mo stretchy="false">)</mo><mo stretchy="false">]</mo><mo>%</mo></mrow></math>, where the last uncertainty reflects that of the branching fraction of the normalization channel <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mo>−</mo></msup><mo stretchy="false">→</mo><mrow><msubsup><mi>D</mi><mrow><mn>1</mn><mo>,</mo><mn>2</mn></mrow><mrow><mo>*</mo><mo>*</mo><mn>0</mn></mrow></msubsup><msup><msubsup><mi>D</mi><mi>s</mi><mo>−</mo></msubsup><mrow><mo stretchy="false">(</mo><mo>*</mo><mo stretchy="false">)</mo></mrow></msup></mrow></math>. The ratio between the tauonic and muonic semileptonic <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>B</mi></math> decays, with the latter taken from world average values, is also determined and found to be <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi mathvariant="script">R</mi><mo stretchy="false">(</mo><msubsup><mrow><mi>D</mi></mrow><mrow><mn>1</mn><mo>,</mo><mn>2</mn></mrow><mrow><mo>*</mo><mo>*</mo><mn>0</mn></mrow></msubsup><mo stretchy="false">)</mo><mo>=</mo><mn>0.13</mn><mo>±</mo><mn>0.03</mn><mrow><mo stretchy="false">(</mo><mi>stat</mi><mo stretchy="false">)</mo></mrow><mo>±</mo><mn>0.01</mn><mrow><mo stretchy="false">(</mo><mi>syst</mi><mo stretchy="false">)</mo></mrow><mo>±</mo><mn>0.02</mn><mo stretchy="false">(</mo><mi>ext</mi><mo stretchy="false">)</mo></mrow></math>.

A.S.W. Abdelmotteleb

A.A. Adefisoye

C.A. Aidala

CERN

J.L. Amey

J.J. Back

I.R. Barbosa

R.J. Barlow

M. Bartolini

J.M. Basels

G. Bassi

P.B. Battista

I.B. Bediaga

N.A. Behling

M.S. Bieker

N.V. Biesuz

F.C.R. Bishop

J.E. Blank

Evidence for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mo>−</mo></msup><mo stretchy="false">→</mo><msup><mi>D</mi><mrow><mo>*</mo><mo>*</mo><mn>0</mn></mrow></msup><msup><mi>τ</mi><mo>−</mo></msup><mover accent="true"><msub><mi>ν</mi><mi>τ</mi></msub><mo stretchy="true">¯</mo></mover></math> Decays

By analyzing <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mo stretchy="false">(</mo><mn>2712.4</mn><mo>±</mo><mn>14.3</mn><mo stretchy="false">)</mo><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mn>6</mn></mrow></msup><mtext> </mtext><mtext> </mtext><mi>ψ</mi><mo stretchy="false">(</mo><mn>3686</mn><mo stretchy="false">)</mo></mrow></math> events collected with the BESIII detector operating at the BEPCII collider, the decays <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>χ</mi></mrow><mrow><mi>c</mi><mn>0</mn><mo>,</mo><mn>1</mn><mo>,</mo><mn>2</mn></mrow></msub><mo stretchy="false">→</mo><mn>3</mn><msubsup><mrow><mi>K</mi></mrow><mrow><mi>S</mi></mrow><mrow><mn>0</mn></mrow></msubsup><msup><mrow><mi>K</mi></mrow><mrow><mo>±</mo></mrow></msup><msup><mrow><mi>π</mi></mrow><mrow><mo>∓</mo></mrow></msup></mrow></math> are observed for the first time with statistical significances greater than <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>10</mn><mi>σ</mi></math>. The branching fractions of these decays are determined to be <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi mathvariant="script">B</mi><mo stretchy="false">(</mo><msub><mrow><mi>χ</mi></mrow><mrow><mi>c</mi><mn>0</mn></mrow></msub><mo stretchy="false">→</mo><mn>3</mn><msubsup><mrow><mi>K</mi></mrow><mrow><mi>S</mi></mrow><mrow><mn>0</mn></mrow></msubsup><msup><mrow><mi>K</mi></mrow><mrow><mo>±</mo></mrow></msup><msup><mrow><mi>π</mi></mrow><mrow><mo>∓</mo></mrow></msup><mo stretchy="false">)</mo><mo>=</mo><mo stretchy="false">(</mo><mn>7.95</mn><mo>±</mo><mn>0.50</mn><mo>±</mo><mn>0.65</mn><mo stretchy="false">)</mo><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>5</mn></mrow></msup></mrow></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi mathvariant="script">B</mi><mo stretchy="false">(</mo><msub><mrow><mi>χ</mi></mrow><mrow><mi>c</mi><mn>1</mn></mrow></msub><mo stretchy="false">→</mo><mn>3</mn><msubsup><mrow><mi>K</mi></mrow><mrow><mi>S</mi></mrow><mrow><mn>0</mn></mrow></msubsup><msup><mrow><mi>K</mi></mrow><mrow><mo>±</mo></mrow></msup><msup><mrow><mi>π</mi></mrow><mrow><mo>∓</mo></mrow></msup><mo stretchy="false">)</mo><mo>=</mo><mo stretchy="false">(</mo><mn>2.62</mn><mo>±</mo><mn>0.08</mn><mo>±</mo><mn>0.19</mn><mo stretchy="false">)</mo><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>4</mn></mrow></msup></mrow></math>, and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi mathvariant="script">B</mi><mo stretchy="false">(</mo><msub><mrow><mi>χ</mi></mrow><mrow><mi>c</mi><mn>2</mn></mrow></msub><mo stretchy="false">→</mo><mn>3</mn><msubsup><mrow><mi>K</mi></mrow><mrow><mi>S</mi></mrow><mrow><mn>0</mn></mrow></msubsup><msup><mrow><mi>K</mi></mrow><mrow><mo>±</mo></mrow></msup><msup><mrow><mi>π</mi></mrow><mrow><mo>∓</mo></mrow></msup><mo stretchy="false">)</mo><mo>=</mo><mo stretchy="false">(</mo><mn>1.72</mn><mo>±</mo><mn>0.07</mn><mo>±</mo><mn>0.15</mn><mo stretchy="false">)</mo><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>4</mn></mrow></msup></mrow></math>, where the first uncertainties are statistical and the second systematic.

M. Ablikim

Russia

M.N. Achasov

X.C. Ai

R. Aliberti

A. Amoroso

Q. An

Y. Bai

JINR

O. Bakina

Y. Ban

H.R. Bao

V. Batozskaya

Mongolia

K. Begzsuren

N. Berger

M. Berlowski

M. Bertani

D. Bettoni

F. Bianchi

E. Bianco

A. Bortone

I. Boyko

R.A. Briere

A. Brueggemann

H. Cai

M.H. Cai

X. Cai

A. Calcaterra

G.F. Cao

N. Cao

Türkiye

S.A. Cetin

X.Y. Chai

J.F. Chang

G.R. Che

Y.Z. Che

G. Chelkov

C. Chen

C.H. Chen

Chao Chen

G. Chen

H.S. Chen

H.Y. Chen

M.L. Chen

S.J. Chen

S.L. Chen

S.M. Chen

T. Chen

X.R. Chen

X.T. Chen

Y.B. Chen

Y.Q. Chen

Z.J. Chen

Z.K. Chen

South Korea

S.K. Choi

Observation of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>χ</mi><mrow><mi>c</mi><mi>J</mi></mrow></msub><mo stretchy="false">→</mo><mn>3</mn><msubsup><mi>K</mi><mi>S</mi><mn>0</mn></msubsup><msup><mi>K</mi><mo>±</mo></msup><msup><mi>π</mi><mo>∓</mo></msup></math>