<p>This work investigates the discovery potential for singly produced vectorlike quarks (VLQs) <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>T</mi></math> (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Q</mi><mo>=</mo><mo>+</mo><mn>2</mn><mo>/</mo><mn>3</mn><mi>e</mi></math>) and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Y</mi></math> (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Q</mi><mo>=</mo><mo>−</mo><mn>4</mn><mo>/</mo><mn>3</mn><mi>e</mi></math>) decaying to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>W</mi><mi>b</mi></math> at future <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>μ</mi><mi>p</mi></math> colliders with <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>5.29</mn></math>, 6.48, and 9.16 TeV, analyzing both leptonic and hadronic <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>W</mi></math> decay channels through detailed detector simulations. The hadronic channel demonstrates superior sensitivity, enabling <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>5</mn><mi>σ</mi></math> discovery up to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>m</mi><mi>T</mi></msub><mo>=</mo><mn>3750</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math> (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>m</mi><mi>Y</mi></msub><mo>=</mo><mn>4100</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math>) at 9.16 TeV with <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>100</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>, while exclusion limits reach <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>m</mi><mi>T</mi></msub><mo>=</mo><mn>4500</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math> (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>g</mi><mo>*</mo></msup><mo>≥</mo><mn>0.06</mn></math>) and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>m</mi><mi>Y</mi></msub><mo>=</mo><mn>4800</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math> (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>κ</mi><mi>Y</mi></msub><mo>≥</mo><mn>0.04</mn></math>)—significantly beyond LHC capabilities. At 5.29 TeV, discovery regions cover <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>g</mi><mo>*</mo></msup><mo>∈</mo><mo stretchy="false">[</mo><mn>0.15</mn><mo>,</mo><mn>0.5</mn><mo stretchy="false">]</mo></math> for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>m</mi><mi>T</mi></msub><mo>∈</mo><mo stretchy="false">[</mo><mn>1500</mn><mo>,</mo><mn>2520</mn><mo stretchy="false">]</mo><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>κ</mi><mi>Y</mi></msub><mo>∈</mo><mo stretchy="false">[</mo><mn>0.12</mn><mo>,</mo><mn>0.5</mn><mo stretchy="false">]</mo></math> for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>m</mi><mi>Y</mi></msub><mo>∈</mo><mo stretchy="false">[</mo><mn>1700</mn><mo>,</mo><mn>2700</mn><mo stretchy="false">]</mo><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math>, with exclusions extending to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>m</mi><mi>T</mi></msub><mo>=</mo><mn>2750</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>m</mi><mi>Y</mi></msub><mo>=</mo><mn>3020</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math>. These results, obtained within a simplified two-parameter framework (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>m</mi><mrow><mi>T</mi><mo>/</mo><mi>Y</mi></mrow></msub></math> and electroweak couplings <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>g</mi><mo>*</mo></msup></math>), establish <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>μ</mi><mi>p</mi></math> colliders as uniquely powerful tools for probing high-mass VLQ states, particularly in the boosted jet regime.</p>

China

Jin-Zhong Han

Yao-Bei Liu

United Kingdom

Sweden

Stefano Moretti

Searching for single production of vectorlike quarks decaying into <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>W</mi><mi>b</mi></math> at a future muon-proton collider

We study the estimation of anomalous charged triple gauge couplings (cTGCs) parameterized in a model-independent Standard Model effective field theory (SMEFT) framework via $\textit{WW}$ production followed by semi-leptonic decay at the $\textit{e}$ $\textit{e}$ colliders. The anomalous part of cTGCs, $\textit{WWV}$ ($\textit{V}$ = $\textit{γ}$, $\textit{Z}$), are given in terms of Wilson coefficients of three CP-conserving and two CP-violating dimension-6 operators in the HISZ basis. We adopt the optimal observable technique (OOT) to extract the sensitivity of these anomalous couplings and compare it with the latest experimental limits on anomalous couplings studied at the LHC. The limits on the anomalous couplings obtained via OOT are significantly tighter than the ones obtained using standard $\textit{χ}$ analysis. The impact of different combinations of the helicity of $\textit{W}$ boson pair in determining the optimal sensitivity is analyzed. The constraints on CP-violating operators from the electron electric dipole moment (EDM) are also discussed.

Sahabub Jahedi

Germany

Jayita Lahiri

India

Amir Subba

Optimal sensitivity of anomalous charged triple gauge couplings through $\textit{W}$ boson helicity at the $\textit{e}$

The most precise measurement to date of the <inline-figure xmlns:ns0='http://www.w3.org/1999/xlink'><link locator='fx001' ns0:type='simple' ns0:href='pii:S0370269325005155/fx001' ns0:role='http://data.elsevier.com/vocabulary/ElsevierContentTypes/23.4' id='ln0250' /><alt-text role='short' id='at0270'>Image 1</alt-text></inline-figure> boson hadronic decay branching fraction ratio <inline-figure xmlns:ns0='http://www.w3.org/1999/xlink'><link locator='fx002' ns0:type='simple' ns0:href='pii:S0370269325005155/fx002' ns0:role='http://data.elsevier.com/vocabulary/ElsevierContentTypes/23.4' id='ln0260' /><alt-text role='short' id='at0280'>Image 2</alt-text></inline-figure> is presented. The measurement is based on a sample of proton-proton collision data from the CERN LHC collected by the CMS experiment at a center-of-mass energy of 13&#8239;TeV in 2016&#8211;2018 with an integrated luminosity of <math altimg='si3.svg'><mn>138</mn><mrow><mspace width='0.2em' /><msup><mrow><mtext>fb</mtext></mrow><mrow><mo>&#8722;</mo><mn>1</mn></mrow></msup></mrow></math>. The large cross section of top quark-antiquark production at the LHC offers a sizable high-purity sample of <inline-figure xmlns:ns0='http://www.w3.org/1999/xlink'><link locator='fx001' ns0:type='simple' ns0:href='pii:S0370269325005155/fx001' ns0:role='http://data.elsevier.com/vocabulary/ElsevierContentTypes/23.4' id='ln0270' /><alt-text role='short' id='at0290'>Image 3</alt-text></inline-figure> bosons suitable for this measurement. Events with one charged lepton (electron or muon) and at least four jets, two tagged as bottom quark jets, are analyzed. Charm jets are tagged using the presence of a muon inside the jet. The result, <inline-figure xmlns:ns0='http://www.w3.org/1999/xlink'><link locator='fx003' ns0:type='simple' ns0:href='pii:S0370269325005155/fx003' ns0:role='http://data.elsevier.com/vocabulary/ElsevierContentTypes/23.4' id='ln0280' /><alt-text role='short' id='at0300'>Image 4</alt-text></inline-figure>, is consistent with the standard model prediction and is twice as precise as the current world-average value.

Armenia

A. Hayrapetyan

A. Tumasyan

Austria

W. Adam

J.W. Andrejkovic

L. Benato

T. Bergauer

S. Chatterjee

K. Damanakis

M. Dragicevic

P.S. Hussain

M. Jeitler

N. Krammer

A. Li

D. Liko

I. Mikulec

J. Schieck

R. Schöfbeck

D. Schwarz

M. Sonawane

W. Waltenberger

C.E. Wulz

Belgium

T. Janssen

T. Van Laer

P. Van Mechelen

N. Breugelmans

J. D'Hondt

S. Dansana

A. De Moor

M. Delcourt

F. Heyen

S. Lowette

I. Makarenko

D. Müller

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

J. Jaramillo

A. Khalilzadeh

F.A. Khan

K. Lee

A. Malara

M.A. Shahzad

L. Thomas

M. Vanden Bemden

C. Vander Velde

P. Vanlaer

M. De Coen

D. Dobur

G. Gokbulut

Y. Hong

J. Knolle

L. Lambrecht

D. Marckx

K. Mota Amarilo

K. Skovpen

N. Van Den Bossche

J. van der Linden

L. Wezenbeek

A. Benecke

A. Bethani

G. Bruno

C. Caputo

J. De Favereau De Jeneret

C. Delaere

I.S. Donertas

A. Giammanco

A.O. Guzel

Sa. Jain

V. Lemaitre

J. Lidrych

P. Mastrapasqua

T.T. Tran

S. Turkcapar

Brazil

G.A. Alves

E. Coelho

G. Correia Silva

C. Hensel

T. Menezes De Oliveira

C. Mora Herrera

P. Rebello Teles

M. Soeiro

E.J. Tonelli Manganote

A. Vilela Pereira

W.L. Aldá Júnior

M. Barroso Ferreira Filho

H. Brandao Malbouisson

W. Carvalho

J. Chinellato

E.M. Da Costa

G.G. Da Silveira

Measurement of the W boson decay branching fraction ratio <math altimg='si1.svg'><mi mathvariant='script'>B</mi><mo stretchy='false'>(</mo><mi mathvariant='normal'>W</mi><mo stretchy='false'>&#8594;</mo><mi mathvariant='normal'>c</mi><mi mathvariant='normal'>q</mi><mo stretchy='false'>)</mo><mo stretchy='false'>/</mo><mi mathvariant='script'>B</mi><mo stretchy='false'>(</mo><mi mathvariant='normal'>W</mi><mo stretchy='false'>&#8594;</mo><mi mathvariant='normal'>q</mi><msup><mrow><mover accent='true'><mrow><mi mathvariant='normal'>q</mi></mrow><mrow><mo stretchy='false'>&#175;</mo></mrow></mover></mrow><mrow><mo>&#8242;</mo></mrow></msup><mo stretchy='false'>)</mo></math> in proton-proton collisions at <math altimg='si2.svg'><msqrt><mrow><mi>s</mi></mrow></msqrt><mo linebreak='goodbreak' linebreakstyle='after'>=</mo><mn>13</mn><mspace width='0.2em' /><mtext>TeV</mtext></math>

We investigate tripartite quantum steering dynamics in a three-Unruh–DeWitt-detector system, examining both $$1\rightarrow 2$$ (i.e., from Alice to Bob and Charlie) and $$2\rightarrow 1$$ steering (i.e., from Alice and Bob to Charlie) configurations under two paradigmatic entangled initial states: the Greenberger–Horne–Zeilinger (GHZ) and W states. Our analysis demonstrates that $$1\rightarrow 2$$ steering exhibits better resistance to Unruh decoherence than $$2\rightarrow 1$$ steering. Notably, the $$1\rightarrow 2$$ steering of the W state displays a non-monotonic dependence on the acceleration parameter, indicating that the Unruh effect can, in certain regimes, enhance quantum steering. These results suggest that the Unruh effect plays a dual role in tripartite quantum systems, as it can both enhance and degrade quantum steering. Consequently, moving beyond the conventional interpretation of the Unruh effect as merely a source of decoherence, our study provides a new insight by exploring tripartite quantum steering in a relativistic setting.

Si-Han Shang

Shu-Min Wu

Quantum steering of GHZ and W states in relativistic motion

A search is performed for long-lived heavy neutral leptons (HNLs), produced through the decay of a $\textit{W}$ boson along with a muon or electron. Two channels are explored: a leptonic channel, in which the HNL decays into two leptons and a neutrino, and a semi-leptonic channel, in which the HNL decays into a lepton and a charged pion. The search is performed with 140 fb of $$ \sqrt{s} $$ = 13 TeV proton-proton collision data collected by ATLAS during Run 2 of the Large Hadron Collider. No excess of events is observed; Dirac-like and Majorana-like HNLs with masses below 14.5 GeV and mixing coefficients as small as 10 are excluded at the 95% confidence level. The results are interpreted under different assumptions on the flavour of the leptons from the HNL decays.

France

G. Aad

Norway

E. Aakvaag

United States

B. Abbott

United Arab Emirates

S. Abdelhameed

K. Abeling

N. Abicht

S. Abidi

M. Aboelela

Morocco

A. Aboulhorma

Israel

H. Abramowicz

Y. Abulaiti

Italy

B. Acharya

A. Ackermann

C. Adam Bourdarios

Poland

L. Adamczyk

S. Addepalli

M. Addison

J. Adelman

Türkiye

A. Adiguzel

T. Adye

A. Affolder

Y. Afik

Spain

M. Agaras

A. Aggarwal

Romania

C. Agheorghiesei

Azerbaijan

F. Ahmadov

S. Ahuja

X. Ai

G. Aielli

A. Aikot

M. Ait Tamlihat

B. Aitbenchikh

M. Akbiyik

T. Åkesson

A. Akimov

Japan

D. Akiyama

N. Akolkar

S. Aktas

G. Alberghi

Canada

J. Albert

P. Albicocco

G. Albouy

S. Alderweireldt

Z. Alegria

Switzerland

M. Aleksa

I. Aleksandrov

C. Alexa

Greece

T. Alexopoulos

F. Alfonsi

M. Algren

M. Alhroob

Czechia

B. Ali

Saudi Arabia

H. Ali

S. Ali

S. Alibocus

South Africa

M. Aliev

Search for heavy neutral leptons in decays of W bosons using leptonic and semi-leptonic displaced vertices in $$ \sqrt{s} $$ = 13 TeV $\textit{pp}$ collisions with the ATLAS detector