We present a systematic analysis of the Higgs signal strengths at 125 GeV and 95 GeV in a non-supersymmetric $ U(1)_X $ model with vector-like fermions ( $ U(1)_X $ VLFM). This framework extends the Standard Model (SM) by introducing an additional $ U(1)_X $ gauge symmetry, three right-handed neutrinos, two singlet Higgs fields ($\textit{ϕ}$ and $\textit{S}$), and one generation of vector-like quarks and leptons. The scalar fields mix in the neutral CP-even sector, yielding two Higgs-like states around 95 GeV and 125 GeV. We perform a $ \chi^2 $ analysis that combines the Higgs signal strength measurements at 125 GeV from ATLAS and CMS, including the $ \gamma\gamma $ , $ WW^* $ , $ ZZ^* $ , $ b\bar{b} $ , and $ \tau\bar{\tau} $ channels, together with the 95 GeV excesses observed in the diphoton and $ b\bar{b} $ final states reported by CMS and LEP. Our results indicate that the $ U(1)_X $ VLFM successfully reproduces the observed signal strengths of the 125 GeV Higgs while simultaneously explaining the 95 GeV excess. The parameters $ g_X $ , $ g_{YX} $ , $ v_S $ , $ v_P $ , and the new Yukawa couplings play a crucial role in achieving this consistency.

China

Rong-Zhi Sun

Shu-Min Zhao

Meng-Zi Cao

Song Gao

Portugal

Xing-Xing Dong

Higgs Bosons at 95 and 125 GeV in the $\textit{U}$(1) $\textit{X}$ VLFM * Supported by National Natural Science Foundation of China (NNSFC) (2075074), Natural Science Foundation of Hebei Province (A2023201040, A2022201022, A2022201017, A2023201041), Natural Science Foundation of Hebei Education Department (QN2022173), the Project of the China Scholarship Council (CSC) (202408130113). This work is also supported by Fundação para a Ciência e a Tecnologia (FCT, Portugal) through the project UID/00777/2025 (https://doi.org/ 10.54499/UID/00777/2025)

Using $\textit{e}$ $\textit{e}$ collision data at 19 center-of-mass energies ranging from 4$\textit{.}$396 to 4$\textit{.}$951 GeV corresponding to a total integrated luminosity of 8$\textit{.}$86 fb collected by the BESIII detector, the process $\textit{e}$ $\textit{e}$ → $\textit{K}$ $\textit{K}$ $\textit{π}$ $\textit{J/ψ}$ + c.c. is observed for the first time, with a statistical significance of 9$\textit{.}$4$\textit{σ}$ summing up all the data samples. Here, c.c. stands for the charge conjugated mode. For this process, the cross section and the upper limit at the 90% confidence level are reported at each of the 19 center-of-mass energies. No statistically significant vector structures are observed in the cross section line shape, nor as intermediate states of combinations of $\textit{Kπ}$, $$ K\overline{K} $$ , $$ K\overline{K}\pi $$ , $\textit{KJ/ψ}$, $\textit{πJ/ψ}$, and $\textit{KπJ/ψ}$ seen at individual energy points or in the combined data sample.

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

F. Bianchi

E. Bianco

A. Bortone

I. Boyko

United States

R. Briere

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

C. Chen

Chao Chen

G. Chen

H. Chen

M. Chen

S. Chen

T. Chen

X. Chen

Y. Chen

Z. Chen

J. Cheng

South Korea

S. Choi

X. Chu

G. Cibinetto

F. Cossio

United Kingdom

J. Cottee-Meldrum

J. Cui

H. Dai

J. Dai

X. Dai

A. Dbeyssi

R. Boer

F. Mori

D. Dedovich

C. Deng

Z. Deng

A. Denig

I. Denysenko

M. Destefanis

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

L. Fava

F. Feldbauer

G. Felici

C. Feng

J. Feng

L. Feng

First measurement of the cross sections for $\textit{e}$ + $\textit{e}$ $\textit{−}$ $\textit{→ K}$ 0 $\textit{K}$ $\textit{−}$ $\textit{π}$ + $\textit{J/ψ}$ + c.c. at $$ \sqrt{s} $$ from 4.396 to 4.951 GeV

Axionlike particles (ALPs) are promising candidates for mediating interactions between a dark sector and the Standard Model (SM). In this work, considering the effective interactions of ALPs with the SM gauge bosons and a fermion dark matter (DM), we explore the DM relic satisfied parameter space and assess its testability through indirect searches. The effect of early kinetic decoupling is also discussed in the resonant regime. The potential of probing such ALP-portal fermionic DM at the electron-positron colliders is investigated with the monophoton plus missing energy final states. We show that a spectacular distinction between the signal and SM background is possible via the missing energy variable, the seed of which lies in the ALP-photon interaction, which also governs the relic density of DM. We further discuss the sensitivity of ALP-photon coupling using the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>χ</mi><mn>2</mn></msup></math> analysis at the future electron-positron collider specifications.

India

Subhaditya Bhattacharya

Sahabub Jahedi

Soumen Kumar Manna

Arunansu Sil

Probing ALP-portal fermionic dark matter at the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mi>e</mi></mrow><mrow><mo>+</mo></mrow></msup><msup><mrow><mi>e</mi></mrow><mrow><mo>−</mo></mrow></msup></mrow></math> colliders

The Dalitz decay <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msup><mi>π</mi><mn>0</mn></msup><mo>→</mo><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mi>γ</mi></mrow></math> has been measured with the highest statistical accuracy obtained so far in the <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>γ</mi><mi>p</mi><mo>→</mo><msup><mi>π</mi><mn>0</mn></msup><mi>p</mi></mrow></math> reaction with the A2 tagged-photon facility at the Mainz Microtron, MAMI. The value of the slope parameter for the <math xmlns="http://www.w3.org/1998/Math/MathML"><msup><mi>π</mi><mn>0</mn></msup></math> electromagnetic transition form factor, <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>a</mi><mi>π</mi></msub><mo>=</mo><mn>0.0315</mn><mo>±</mo><mn>0</mn><mo>.</mo><msub><mn>0026</mn><mi>stat</mi></msub><mo>±</mo><mn>0</mn><mo>.</mo><msub><mn>0010</mn><mi>syst</mi></msub></mrow></math>, is obtained from the analysis of <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mn>2.4</mn><mo>×</mo><msup><mn>10</mn><mn>6</mn></msup></mrow></math> <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msup><mi>π</mi><mn>0</mn></msup><mo>→</mo><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mi>γ</mi></mrow></math> observed decays. Within experimental uncertainties, it is in agreement with existing measurements and theoretical calculations, with its own uncertainty being smaller than previous results based on the analysis of <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msup><mi>π</mi><mn>0</mn></msup><mo>→</mo><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mi>γ</mi></mrow></math> decays.

S. Prakhov

L. Heijkenskjöld

Switzerland

S. Abt

P. Achenbach

F. Afzal

Canada

Z. Ahmed

K. Altangerel

J.R.M. Annand

M. Bashkanov

R. Beck

M. Biroth

JINR

N.S. Borisov

A. Braghieri

W.J. Briscoe

F. Cividini

C. Collicott

S. Costanza

M. Dieterle

A.S. Dolzhikov

E.J. Downie

P. Drexler

S. Fegan

S. Gardner

D. Ghosal

D.I. Glazier

I. Gorodnov

W. Gradl

M. Günther

G.M. Gurevich

D. Hornidge

G.M. Huber

A. Käser

V.L. Kashevarov

S.J.D. Kay

Croatia

M. Korolija

B. Krusche

A. Lazarev

K. Livingston

S. Lutterer

I.J.D. MacGregor

D.M. Manley

P.P. Martel

R. Miskimen

M. Mocanu

E. Mornacchi

C. Mullen

A. Neganov

A. Neiser

M. Ostrick

P.B. Otte

D. Paudyal

P. Pedroni

A. Powell

E. Rickert

T. Rostomyan

V. Sokhoyan

K. Spieker

O. Steffen

I.I. Strakovsky

Th. Strub

I. Supek

M. Thiel

A. Thomas

Yu. A. Usov

S. Wagner

D.P. Watts

D. Werthmüller

J. Wettig

M. Wolfes

N. Zachariou

New high-statistics measurement of the <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msup><mi>π</mi><mn>0</mn></msup><mo>→</mo><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mi>γ</mi></mrow></math> Dalitz decay at the Mainz Microtron

We present the first rainbow-ladder Dyson-Schwinger equations study of the pion’s chiral-odd, twist-3 parton distribution <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>e</mi><mi mathvariant="normal">q</mi></msub><mo stretchy="false">(</mo><mi>x</mi><mo stretchy="false">)</mo></math>. By deriving a novel Dyson–Schwinger equation for the pion’s quark–quark correlation matrix, we simultaneously extract from it both the unpolarized twist-2 parton distribution function <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>f</mi><mi mathvariant="normal">q</mi></msub><mo stretchy="false">(</mo><mi>x</mi><mo stretchy="false">)</mo></math> and the twist-3 distribution <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>e</mi><mi mathvariant="normal">q</mi></msub><mo stretchy="false">(</mo><mi>x</mi><mo stretchy="false">)</mo></math>. Our results show that chiral symmetry strongly suppresses the twist-2 component of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>e</mi><mi mathvariant="normal">q</mi></msub><mo stretchy="false">(</mo><mi>x</mi><mo stretchy="false">)</mo></math>, leaving the genuine twist-3 quark-gluon component dominant and featuring a node. We therefore argue that the genuine twist-3 term can make a substantial contribution to hadronic <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>e</mi><mo stretchy="false">(</mo><mi>x</mi><mo stretchy="false">)</mo></math>, producing a nonmonotonic structure that is a clear imprint of intrinsic quark-gluon correlations. We point out that the existence of a humplike feature is compatible with, although not uniquely indicated by, recent proton extractions and awaits more precise determination.

Chao Shi

Liming Lu

Ian C. Cloët

Wenbao Jia

Peter C. Tandy

Imprint of intrinsic quark-gluon correlations: A nonmonotonic feature in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>e</mi><mo stretchy="false">(</mo><mi>x</mi><mo stretchy="false">)</mo></math>

Recent Belle II data on <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mo>+</mo></msup><mo stretchy="false">→</mo><msup><mi>K</mi><mo>+</mo></msup><msub><mi>E</mi><mrow><mi>miss</mi></mrow></msub></math> show an excess consistent with a two-body decay involving a light invisible particle with mass around 2.1 GeV. We present a UV-complete explanation based on a Higgsed <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>U</mi><mo stretchy="false">(</mo><mn>1</mn><msup><mo stretchy="false">)</mo><mo>′</mo></msup></math> gauge symmetry with a light vector boson <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>Z</mi><mo>′</mo></msup></math> and a vectorlike top partner, which naturally enhances <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>b</mi><mo stretchy="false">→</mo><mi>s</mi></math> transitions. While the minimal model can reproduce the required <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>B</mi><mo stretchy="false">→</mo><msup><mi>K</mi><mrow><mo stretchy="false">(</mo><mo>*</mo><mo stretchy="false">)</mo></mrow></msup><msup><mi>Z</mi><mo>′</mo></msup></math> rate, it is excluded by LHCb searches for resonant dimuon decays due to unavoidable loop-induced couplings of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>Z</mi><mo>′</mo></msup></math> to charged leptons. We show that a minimal extension with an additional light <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>U</mi><mo stretchy="false">(</mo><mn>1</mn><msup><mo stretchy="false">)</mo><mo>′</mo></msup></math>-charged singlet fermion allows <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>Z</mi><mo>′</mo></msup></math> to decay dominantly invisibly, evades existing constraints coming also from dark photon and collider searches as well as Higgs measurements, and can simultaneously account for the Belle II excess and the observed dark matter abundance through resonant thermal freeze-out.

Slovenia

Patrick D. Bolton

Dark light shining on <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>B</mi><mo stretchy="false">→</mo><msup><mrow><mi>K</mi></mrow><mrow><mo stretchy="false">(</mo><mo>*</mo><mo stretchy="false">)</mo></mrow></msup><msub><mrow><mi>E</mi></mrow><mrow><mrow><mi>miss</mi></mrow></mrow></msub></mrow></math>