Within the framework of nonrelativistic QCD (NRQCD) factorization, and based on the Collins-Soper operator definition of fragmentation functions, we present a systematic calculation of the fragmentation functions for a heavy quark fragmenting into color-singlet $\textit{P}$-wave quarkonium states. After reproducing and confirming the known leading-order results, we further compute the relativistic corrections up to order $$ \mathcal{O}\left({v}^2\right) $$ . Our analysis applies both to quarkonium systems composed of heavy quarks with the same flavor and to $\textit{B}$ -type mesons formed by heavy quarks of different flavors. Numerical results show that, for all color-singlet $\textit{P}$-wave channels, the $$ \mathcal{O}\left({v}^2\right) $$ relativistic corrections give sizable negative contributions over most of the momentum-fraction $\textit{z}$ region. We further compute inclusive cross sections for $\textit{P}$-wave quarkonium plus charmed hadrons in $\textit{e}$ $\textit{e}$ annihilation via the single photon process up to $$ \mathcal{O}\left({v}^2\right) $$ by applying our obtained fragmentation functions, and the resulting predictions are consistent with the full fixed-order results in the high-energy region.

China

Sai Cui

Sheng-Juan Jiang

Guang-Zhi Xu

Kui-Yong Liu

Order-$\textit{v}$ 2 relativistic corrections to heavy-quark fragmentation into $\textit{P}$-wave quarkonium states

Constraints on Wilson coefficients (WCs) corresponding to dimension-6 operators of the standard model effective field theory (SMEFT) are determined from a simultaneous fit to seven sets of CMS measurements probing Higgs boson, electroweak vector boson, top quark, and multijet production. Measurements of electroweak precision observables are also included and provide complementary constraints to those from the CMS experiment. The CMS measurements, using LHC proton-proton collision data at $$\sqrt{s}=13\,\text {Te}\text {V} $$ , corresponding to integrated luminosities of 36.3 or 138 $$\,\text {fb}^{-1}$$ , are chosen to provide sensitivity to a broad set of operators, for which consistent SMEFT predictions can be derived. These are primarily measurements of differential cross sections which are parameterized as functions of the WCs. In measurements targeting $${\text {t}} (\bar{\textrm{t}})\text {X} $$ production, SMEFT effects are modelled at the detector level. Individual constraints on 64 WCs, and constraints on 43 linear combinations of WCs, are obtained.

Armenia

V. Chekhovsky

A. Hayrapetyan

V. Makarenko

A. Tumasyan

Austria

W. Adam

J. Andrejkovic

L. Benato

T. Bergauer

K. Damanakis

M. Dragicevic

C. Giordano

P. Hussain

Belgium

M. Jeitler

N. Krammer

A. Li

D. Liko

I. Mikulec

J. Schieck

R. Schöfbeck

D. Schwarz

M. Sonawane

W. Waltenberger

C.E. Wulz

T. Janssen

H. Kwon

T. Laer

P. Mechelen

J. Bierkens

N. Breugelmans

J. D’Hondt

S. Dansana

A. Moor

M. Delcourt

F. Heyen

Y. Hong

S. Lowette

I. Makarenko

D. Müller

S. Tavernier

M. Tytgat

G. Onsem

S. Putte

D. Vannerom

B. Bilin

B. Clerbaux

A. Das

I. Bruyn

G. Lentdecker

H. Evard

L. Favart

P. Gianneios

A. Khalilzadeh

F. Khan

A. Malara

M. Shahzad

L. Thomas

M. Vanden Bemden

C. Vander Velde

P. Vanlaer

F. Zhang

M. Coen

D. Dobur

G. Gokbulut

J. Knolle

L. Lambrecht

D. Marckx

K. Skovpen

N. Bossche

J. Linden

J. Vandenbroeck

L. Wezenbeek

S. Bein

A. Benecke

A. Bethani

G. Bruno

A. Cappati

J. Favereau De Jeneret

C. Delaere

A. Giammanco

A. Guzel

Sa. Jain

V. Lemaitre

J. Lidrych

P. Mastrapasqua

S. Turkcapar

Brazil

G. Alves

E. Coelho

G. Correia Silva

C. Hensel

T. Menezes De Oliveira

C. Mora Herrera

P. Rebello Teles

M. Soeiro

E. Tonelli Manganote

A. Vilela Pereira

W. Aldá Júnior

M. Barroso Ferreira Filho

H. Brandao Malbouisson

W. Carvalho

J. Chinellato

Combined effective field theory interpretation of Higgs boson, electroweak vector boson, top quark, and multijet measurements

We consider the V-A Fermi interaction and apply an earlier developed method for summing up the leading asymptotics for scattering amplitudes in non-renormalizable theories. We consider the amplitude of fermion-antifermion scattering and derive the corresponding RG equation that sums the leading logarithmic contributions just like in renormalizable models. Numerical solution of this equation in the asymptotic regime <italic>s</italic>&#8239;&#8764;&#8239; <italic>t</italic>&#8239;&#8764;&#8239; <italic>u</italic>&#8239;&#8764;&#8239; <italic>E</italic> 2&#8239;&#8594;&#8239;&#8734; leads to amplitude logarithmically decreasing with energy, thus restoring the unitarity violated at the tree level.

Russia

Arthur Borlakov

Dmitry Kazakov

Asymptotic freedom of V-A Fermi interaction

In light of ongoing issues with the first-row unitarity test of the Cabibbo-Kobayashi-Maskawa matrix, we showcase a global fit to measurements of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>K</mi><mo stretchy="false">→</mo><mo>ℓ</mo><mi>ν</mi></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>K</mi><mo stretchy="false">→</mo><mi>π</mi><mo>ℓ</mo><mi>ν</mi></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>τ</mi><mo stretchy="false">→</mo><mi>K</mi><mi>ν</mi></math>, and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>τ</mi><mo stretchy="false">→</mo><mi>K</mi><mi>π</mi><mi>ν</mi></math> decays for the first time. Fitting the semileptonic and three-body <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>τ</mi></math> decay data simultaneously becomes computationally feasible because we employ a simple form factor parametrization for the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>K</mi><mi>π</mi></math> form factor that manifestly connects the semileptonic and pair-production regions. We find good agreement with the data and use our analyses to infer <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">|</mo><msub><mi>V</mi><mrow><mi>u</mi><mi>s</mi></mrow></msub><mo stretchy="false">|</mo></math> and the parameters for the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>K</mi><mi>π</mi></math> form factors. Our result for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">|</mo><msub><mi>V</mi><mrow><mi>u</mi><mi>s</mi></mrow></msub><mo stretchy="false">|</mo></math> sits close to the results extracted from exclusive <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>K</mi><mrow><mo>ℓ</mo><mn>2</mn></mrow></msub></math> and somewhat above the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>K</mi><mrow><mo>ℓ</mo><mn>3</mn></mrow></msub></math> decay and inclusive <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>τ</mi></math> decay result. Moreover, our results for the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>K</mi><mo stretchy="false">→</mo><mi>π</mi></math> vector form factor at zero momentum transfer are compatible with lattice QCD determinations, despite not using lattice QCD inputs for this quantity in our fit of the hadronic matrix elements. We are further able to determine some of the pole parameters of the individual scalar and vector <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>K</mi><mi>π</mi></math> resonances with masses below the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>τ</mi></math> mass. We caution that our results account only for short-distance electromagnetic corrections but not long-distance contributions; this is due to the lack of a consistent description of long-distance corrections to the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>K</mi><mi>π</mi></math> matrix elements both above and below threshold for an arbitrary model of the form factors.

Matthew Kirk

Danny van Dyk

Global determination of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mo stretchy="false">|</mo><msub><mrow><mi>V</mi></mrow><mrow><mi>u</mi><mi>s</mi></mrow></msub><mo stretchy="false">|</mo></mrow></math>

Within the framework of nonrelativistic quantum chromodynamics (NRQCD) factorization, we compute the $$ \mathcal{O}\left({v}^4\right) $$ relativistic corrections to the fragmentation of a heavy quark into the color-singlet $$ {}^1{S}_0^{\left[1\right]} $$ and $$ {}^3{S}_1^{\left[1\right]} $$ quarkonium states. Using the Collins-Soper definition of the fragmentation function, we reproduce the known $$ \mathcal{O}\left({v}^2\right) $$ results. We find that the $$ \mathcal{O}\left({v}^4\right) $$ correction gives a positive contribution relative to the leading order result over a wide range of the light-cone momentum fraction $\textit{z}$, while its magnitude remains much smaller than that of the $$ \mathcal{O}\left({v}^2\right) $$ correction. This behavior indicates a good convergence of the NRQCD relativistic expansion in this process. We further extend the calculation to the fragmentation functions in the unequal-mass case at $$ \mathcal{O}\left({v}^4\right) $$ and obtain the corresponding analytical expressions.

Yi-Jie Li

Order-$\textit{v}$ 4 corrections to heavy quark fragmentation to $\textit{S}$-wave heavy quarkonium

A search for nonresonant new physics phenomena in high-mass dilepton events produced in association with b-tagged jets is performed using proton-proton collision data collected in 2016–2018 by the CMS experiment at the CERN LHC, at a center-of-mass energy of 13 TeV corresponding to an integrated luminosity of 138 fb . The analysis considers two effective field theory models with dimension-six operators; involving four-fermion contact interactions between two leptons ($\textit{ℓℓ}$, electrons or muons) and b or s quarks (bb$\textit{ℓℓ}$ and bs$\textit{ℓℓ}$). Two lepton flavor combinations (ee and $\textit{μμ}$) are required and events are classified as having 0, 1, or ≥2 b-tagged jets in the final state. No significant excess is observed over the standard model backgrounds. Upper limits are set on the production cross section of the new physics signals. These translate into lower limits on the energy scale Λ of 6.9 to 9.0 TeV in the bb$\textit{ℓℓ}$ model, depending on model parameters, and on the ratio of energy scale and effective coupling, Λ/$\textit{g}$ , of 2.0 to 2.6 TeV in the bs$\textit{ℓℓ}$ model. Lepton flavor universality is also tested by comparing the dielectron (ee) and dimuon ($\textit{μμ}$) mass spectra for different b-tagged jet multiplicities. No significant deviation from the standard model expectation of unity is observed.

C. Velde

N. Den Bossche

J. De Favereau De Jeneret

Search for nonresonant new physics signals in high-mass dilepton events produced in association with b-tagged jets in proton-proton collisions at $$\sqrt{s}=13$$ TeV

This paper presents a search for new physics through the process where a massive particle, X, decays into a Higgs boson and a second particle, Y. The Higgs boson subsequently decays into a bottom quark–antiquark pair, which is reconstructed as a single large-radius jet. The decay products of Yare also assumed to produce a single large-radius jet. The identification of the Yparticle is enhanced by computing the anomaly score of its candidate jet using an autoencoder, which measures deviations from typical quark- or gluon-induced jets. This allows a simultaneous search for multiple Ydecay scenarios within a single analysis. In the main benchmark process, Yis a scalar particle that decays into a Wboson pair. Two other scalar Ydecay processes are also considered as benchmarks: decays to a light quark–antiquark pair, and decays to a top quark–antiquark pair. A fourth benchmark process considers Yas a hadronically decaying top quark, arising from the decay of a vector-like quark into a top quark and a Higgs boson. Data recorded by the CMS experiment at a center-of-mass energy of 13 $$\,\text {Te}\hspace{-.08em}\text {V}$$ in 2016–2018, corresponding to an integrated luminosity of 138 $$\,\text {fb}^{-1}$$ , are analyzed. The search covers Xmasses between 1.4 and 3.0 $$\,\text {Te}\hspace{-.08em}\text {V}$$ and Ymasses between 90 and 400 $$\,\text {Ge}\hspace{-.08em}\text {V}$$ , with all simulated signals produced in the narrow-width approximation. No significant excess above the standard model background expectation is observed. The most stringent upper limits to date are placed on benchmark signal cross sections for various masses of X and Y particles

M. Matthewman

M. Shooshtari

D. Ocampo Henao

P. Kashko

J. Song

P. Malek

T. Oliveira

Search for resonances decaying to an anomalous jet and a Higgs boson in proton–proton collisions at $$\sqrt{s}=13\,\text {Te}\hspace{-.08em}\text {V} $$

A sample of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>365</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math> of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></mrow><mo stretchy="false">→</mo><mi mathvariant="normal">ϒ</mi><mo stretchy="false">(</mo><mn>4</mn><mi>S</mi><mo stretchy="false">)</mo><mo stretchy="false">→</mo><mrow><mi>B</mi><mover accent="true"><mi>B</mi><mo stretchy="false">¯</mo></mover></mrow></math> data collected by the Belle II experiment is used to measure the partial branching fractions of charmless semileptonic <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>B</mi></math> meson decays and determine the magnitude of the Cabibbo-Kobayashi-Maskawa (CKM) matrix element <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>V</mi><mrow><mi>u</mi><mi>b</mi></mrow></msub></math>. Events containing a signal electron or muon <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo>ℓ</mo></math> and a fully reconstructed hadronic <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>B</mi></math> decay that constrains the signal kinematics are selected, while the rest of the event defines the hadronic system <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>X</mi><mi>u</mi></msub></math> associated with the signal. To discriminate the signal from the 50-times larger background originating from CKM-favored semileptonic <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>B</mi></math> decays, a template fit is performed in both signal and control regions after applying an optimized selection. The partial branching fraction measured for lepton energies greater than 1 GeV in the signal <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>B</mi></math> meson rest frame is <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi mathvariant="normal">Δ</mi><mi mathvariant="script">B</mi></mrow><mo stretchy="false">(</mo><mrow><mi>B</mi><mo stretchy="false">→</mo><msub><mi>X</mi><mi>u</mi></msub><mo>ℓ</mo><mi>ν</mi></mrow><mo stretchy="false">)</mo><mo>=</mo><mo stretchy="false">(</mo><mn>1.54</mn><mo>±</mo><mn>0.08</mn><mrow><mo stretchy="false">(</mo><mi>stat</mi><mo stretchy="false">)</mo></mrow><mo>±</mo><mn>0.12</mn><mrow><mo stretchy="false">(</mo><mi>syst</mi><mo stretchy="false">)</mo></mrow><mo stretchy="false">)</mo><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>3</mn></mrow></msup></math>. From this measurement, using the Gambino, Giordano, Ossola, Uraltsev theoretical framework, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">|</mo><msub><mi>V</mi><mrow><mi>u</mi><mi>b</mi></mrow></msub><mo stretchy="false">|</mo><mo>=</mo><mo stretchy="false">(</mo><mn>4.01</mn><mo>±</mo><mn>0.1</mn><msubsup><mn>9</mn><mrow><mo>−</mo><mn>0.08</mn></mrow><mrow><mo>+</mo><mn>0.07</mn></mrow></msubsup><mo stretchy="false">)</mo><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>3</mn></mrow></msup></math> is determined, where the uncertainties are experimental and theoretical, respectively. This value is consistent with the world average obtained from previous inclusive measurements. Different theoretical predictions and partial branching fractions measured in other phase-space regions, defined by additional selections on the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>X</mi><mi>u</mi></msub></math> and leptonic system masses, are also used to determine <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">|</mo><msub><mi>V</mi><mrow><mi>u</mi><mi>b</mi></mrow></msub><mo stretchy="false">|</mo></math>. This allows for a comparison of the resulting values across theoretical frameworks and phase-space regions.

M. Abumusabh

I. Adachi

K. Adamczyk

L. Aggarwal

H. Ahmed

Y. Ahn

H. Aihara

N. Akopov

S. Alghamdi

M. Alhakami

A. Aloisio

N. Althubiti

K. Amos

N. Anh Ky

C. Antonioli

D.M. Asner

H. Atmacan

T. Aushev

R. Ayad

V. Babu

H. Bae

N.K. Baghel

S. Bahinipati

P. Bambade

Sw. Banerjee

M. Barrett

M. Bartl

J. Baudot

A. Beaubien

F. Becherer

J. Becker

J.V. Bennett

F.U. Bernlochner

V. Bertacchi

M. Bertemes

E. Bertholet

M. Bessner

S. Bettarini

V. Bhardwaj

B. Bhuyan

F. Bianchi

T. Bilka

D. Biswas

A. Bobrov

D. Bodrov

G. Bonvicini

J. Borah

A. Boschetti

A. Bozek

M. Bračko

P. Branchini

R.A. Briere

T.E. Browder

A. Budano

S. Bussino

Q. Campagna

M. Campajola

L. Cao

G. Casarosa

C. Cecchi

P. Chang

Measurement of inclusive <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>B</mi><mo stretchy="false">→</mo><msub><mi>X</mi><mi>u</mi></msub><mo>ℓ</mo><mi>ν</mi></math> partial branching fractions and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">|</mo><msub><mi>V</mi><mrow><mi>u</mi><mi>b</mi></mrow></msub><mo stretchy="false">|</mo></math> at Belle II