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)

We present a comprehensive investigation of single- $${\Lambda }$$ hyperon production via the lepton-nucleon deep inelastic scattering (LNDIS) process, $${\ell }^{-}$$ + $\textit{p}$ $${\rightarrow }$$ $${\nu }_{\ell }$$ + $${\Lambda }$$ , in the experimental environment of electron–positron colliders. Our approach utilizes incident leptons originating from the decays of resonances ( $${J/\psi }$$ , $${\psi }(2S)$$ , $${\Upsilon }(1S)$$ , $${\Upsilon }(2S)$$ , and $$Z^{0}$$ ) produced in $$e^{+}e^{-}$$ collisions, which then scatter off stationary protons in the surrounding detector materials. The differential and total cross sections are calculated using baryonic transition form factors parameterized with the $\textit{z}$-expansion scheme within both the quantum chromodynamics (QCD) sum rule and lattice QCD frameworks. Our results indicate that the cross section increases with center-of-mass energy and is highly sensitive to the choice of form factors, resulting in significant theoretical uncertainties. This study highlights the experimental challenges in observing the LNDIS process at $$e^{+}e^{-}$$ colliders and underscores the need for improved determination of baryonic form factors. It serves as a valuable reference for future experimental searches and suggests that an anomalous observation of single- $${\Lambda }$$ hyperon production at $$e^{+}e^{-}$$ colliders could indicate new physics.

Yueling Yang

Peisheng Tian

Shuangshi Fang

Bingbing Yang

Junfeng Sun

The feasibility of single- $${\Lambda }$$ production via $${\ell }^{-}$$ + $\textit{p}$ $${\rightarrow }$$ $${\Lambda }$$ + $${\nu }_{\ell }$$ at $$e^{+}e^{-}$$ colliders

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

<p>A search for the pair production of heavy spin-<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>1</mn><mo>/</mo><mn>2</mn></math> or spin-<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>3</mn><mo>/</mo><mn>2</mn></math> resonances (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>t</mi><mo>*</mo></msup></math>) in proton-proton collisions at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>13</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></math> is presented. Data collected with the CMS detector at the CERN LHC from 2016 to 2018 corresponding to an integrated luminosity of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>138</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math> are used. The analysis targets benchmark signal scenarios where one <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>t</mi><mo>*</mo></msup></math> decays into a top quark (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>t</mi></math>) and a photon (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>γ</mi></math>), and the other into a <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>t</mi></math> quark and a gluon (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>g</mi></math>), i.e., <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>p</mi><mi>p</mi><mo stretchy="false">→</mo><msup><mrow><mi>t</mi></mrow><mrow><mo>*</mo></mrow></msup><mover accent="true"><mrow><msup><mrow><mi>t</mi></mrow><mrow><mo>*</mo></mrow></msup></mrow><mrow><mo stretchy="true">¯</mo></mrow></mover><mo stretchy="false">→</mo><mi>t</mi><mi>t</mi><mi>γ</mi><mi>g</mi></mrow></math>. All-hadronic final states from the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>t</mi></math> pair decay chain are selected using jet substructure techniques. The signal is probed as a function of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>t</mi><mo>*</mo></msup></math> candidate mass, which is reconstructed using the photon and a top quark candidate jet. No significant deviation from the background-only hypothesis is found. Observed (expected) upper limits on the signal cross section at 95% confidence level are set, excluding masses of spin-<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>1</mn><mo>/</mo><mn>2</mn></math> <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>t</mi><mo>*</mo></msup></math> particles below 930 (930) GeV and spin-<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>3</mn><mo>/</mo><mn>2</mn></math> <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>t</mi><mo>*</mo></msup></math> particles below 1330 (1390) GeV. This analysis marks the first search for heavy resonances in the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mrow><mi>t</mi><mover accent="true"><mrow><mi>t</mi></mrow><mrow><mo stretchy="false">¯</mo></mrow></mover></mrow><mi>γ</mi><mi>g</mi></mrow></math> channel. Exploiting the high-energy photon to reduce the backgrounds, this search achieves sensitivity competitive with <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>p</mi><mi>p</mi><mo stretchy="false">→</mo><msup><mrow><mi>t</mi></mrow><mrow><mo>*</mo></mrow></msup><mover accent="true"><mrow><msup><mrow><mi>t</mi></mrow><mrow><mo>*</mo></mrow></msup></mrow><mrow><mo stretchy="true">¯</mo></mrow></mover><mo stretchy="false">→</mo><mrow><mi>t</mi><mover accent="true"><mrow><mi>t</mi></mrow><mrow><mo stretchy="false">¯</mo></mrow></mover></mrow><mi>g</mi><mi>g</mi></mrow></math> searches for spin-<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>1</mn><mo>/</mo><mn>2</mn></math> <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>t</mi><mo>*</mo></msup></math> despite the small expected <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>t</mi><mo>*</mo></msup><mo stretchy="false">→</mo><mi>t</mi><mi>γ</mi></math> branching fraction.</p>

Armenia

A. Hayrapetyan

V. Makarenko

A. Tumasyan

Austria

W. Adam

J.W. Andrejkovic

L. Benato

T. Bergauer

M. Dragicevic

C. Giordano

P.S. Hussain

M. Jeitler

N. Krammer

A. Li

D. Liko

M. Matthewman

I. Mikulec

J. Schieck

R. Schöfbeck

D. Schwarz

M. Shooshtari

M. Sonawane

W. Waltenberger

C.E. Wulz

Belgium

T. Janssen

H. Kwon

D. Ocampo Henao

T. Van Laer

P. Van Mechelen

J. Bierkens

N. Breugelmans

J. D’Hondt

S. Dansana

A. De Moor

M. Delcourt

F. Heyen

Y. Hong

P. Kashko

S. Lowette

I. Makarenko

D. Müller

J. Song

S. Tavernier

M. Tytgat

G.P. Van Onsem

S. Van Putte

D. Vannerom

B. Bilin

B. Clerbaux

A.K. Das

I. De Bruyn

G. De Lentdecker

H. Evard

L. Favart

P. Gianneios

A. Khalilzadeh

F.A. Khan

A. Malara

M.A. Shahzad

L. Thomas

M. Vanden Bemden

C. Vander Velde

P. Vanlaer

F. Zhang

M. De Coen

D. Dobur

G. Gokbulut

J. Knolle

L. Lambrecht

D. Marckx

K. Skovpen

N. Van Den Bossche

J. van der Linden

J. Vandenbroeck

L. Wezenbeek

S. Bein

A. Benecke

A. Bethani

G. Bruno

A. Cappati

J. De Favereau De Jeneret

C. Delaere

Search for pair production of heavy resonances in final states with a photon and large-radius jets in proton-proton collisions at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msqrt><mrow><mi>s</mi></mrow></msqrt><mo>=</mo><mn>13</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></mrow></math>