We point out that the odd-in-velocity contribution to the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">O</mi><mo stretchy="false">(</mo><msup><mi>G</mi><mn>4</mn></msup><mo stretchy="false">)</mo></math> radiated angular momentum for two-body scattering is determined by the radiation-reaction (RR) term in the one-loop waveform. This RR term is actually proportional to the tree-level waveform, and this reduces the calculation of the odd-in-velocity contribution to the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">O</mi><mo stretchy="false">(</mo><msup><mi>G</mi><mn>4</mn></msup><mo stretchy="false">)</mo></math> angular momentum loss, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>J</mi></mrow><mrow><mn>2</mn><mtext> </mtext><mtext> </mtext><mi>rad</mi></mrow></msub></mrow></math>, to two loops, instead of three loops as one would expect by power counting. We exploit this simplification, which follows from unitarity, to obtain a closed-form expression for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>J</mi></mrow><mrow><mn>2</mn><mtext> </mtext><mtext> </mtext><mi>rad</mi></mrow></msub></mrow></math> for generic velocities, which resums all fractional post-Newtonian (PN) corrections to the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">O</mi><mo stretchy="false">(</mo><msup><mi>G</mi><mn>4</mn></msup><mo stretchy="false">)</mo></math> angular momentum loss starting at 1.5PN.

France

Carlo Heissenberg

Radiation-reaction and angular momentum loss at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi mathvariant="script">O</mi><mo stretchy="false">(</mo><msup><mrow><mi>G</mi></mrow><mrow><mn>4</mn></mrow></msup><mo stretchy="false">)</mo></mrow></math>

We study an $\textit{O}$($\textit{N}$) invariant surface defect in the Wilson-Fisher conformal field theory (CFT) in $\textit{d}$ = 4 – $\textit{ϵ}$ dimensions. This defect is defined by mass deformation on a two-dimensional surface that generates localized disorder and is conjectured to factorize into a pair of ordinary boundary conditions in $\textit{d}$ = 3. We determine defect CFT data associated with the lightest $\textit{O}$($\textit{N}$) singlet and vector operators up to the third order in the $\textit{ϵ}$-expansion, find agreements with results from numerical methods and provide support for the factorization proposal in $\textit{d}$ = 3. Along the way, we observe surprising non-renormalization properties for surface anomalous dimensions and operator-product-expansion coefficients in the $\textit{ϵ}$-expansion. We also analyze the full conformal anomalies for the surface defect.

United States

Oleksandr Diatlyk

Zimo Sun

Yifan Wang

Surprises in the ordinary: $\textit{O}$($\textit{N}$) invariant surface defect in the $\textit{ϵ}$-expansion

Fusion excitation functions for 19O and 19F + 12C were simultaneously measured along with 20O + 12C using the active-target detector MuSIC@Indiana. Examination of the cross-section just above the barrier reveals a significant suppression of fusion for the 19O + 12C system starting at E <math altimg='si1.svg'><mmultiscripts><mrow><mo>&#8764;</mo></mrow><mprescripts /><mrow><mi mathvariant='normal'>c</mi><mo>.</mo><mi mathvariant='normal'>m</mi><mo>.</mo></mrow><none /></mmultiscripts></math>12 MeV. This suppression is not simply due to the reduced binding of the unpaired neutron in 19O as 17O + 12C does not exhibit the same sharp suppression of the fusion cross-section. Multiple mean-field models are used as a reference to understand the measured fusion excitation functions.

H. Desilets

Rohit Kumar

R.T. deSouza

S. Hudan

C. Ciampi

A. Chbihi

K.W. Brown

K. Godbey

Brazil

B. Pinheiro

E.N. Cardozo

J. Lubian

Impact of pairing and neutron-excess on suppression of the above-barrier fusion cross-section in 19O + 12C

We search for the leptonic decay $ D^+\to e^+\nu_{e} $ using an $ e^+e^- $ collision data sample with an integrated luminosity of 20.3 fb $ ^{-1} $ collected with the BESIII detector at a center-of-mass energy of 3.773 GeV. Significant signal is not observed, and an upper limit on the branching fraction of $ D^+\to e^+\nu_{e} $ is set as $ 9.7 \times 10^{-7} $ , at a confidence level of 90%. Our upper limit is an order of magnitude smaller than the previous limit for this decay mode.

China

M. Ablikim

Russia

M.N. Achasov

Sweden

P. Adlarson

Germany

O. Afedulidis

X.C. Ai

R. Aliberti

Italy

A. Amoroso

Q. An

Y. Bai

O. Bakina

I. Balossino

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

R.A. Briere

A. Brueggemann

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.Y. Chen

S.K. Choi

G. Cibinetto

F. Cossio

J.J. Cui

H.L. Dai

J.P. Dai

A. Dbeyssi

R.E. de Boer

D. Dedovich

C.Q. Deng

Z.Y. Deng

A. Denig

I. Denysenko

M. Destefanis

F. De Mori

B. Ding

X.X. Ding

Y. Ding

J. Dong

L.Y. Dong

M.Y. Dong

X. Dong

M.C. Du

S.X. Du

Y.Y. Duan

Z.H. Duan

P. Egorov

Y.H. Fan

J. Fang

S.S. Fang

W.X. Fang

Y. Fang

Y.Q. Fang

R. Farinelli

L. Fava

F. Feldbauer

G. Felici

C.Q. Feng

J.H. Feng

Y.T. Feng

M. Fritsch

C.D. Fu

J.L. Fu

Y.W. Fu

H. Gao

Search for the leptonic decay ${\boldsymbol D^{\bf +}{\bf\to}{\boldsymbol e}^{\bf +}\boldsymbol\nu_{\boldsymbol e}}$ * Supported in part by the National Key R&D Program of China (2023YFA1606000, 2020YFA0406400, 2020YFA0406300), the National Natural Science Foundation of China(NSFC) (11635010, 11735014, 11935015, 11935016, 11875054, 11935018, 12025502, 12035009, 12035013, 12061131003, 12192260, 12192261, 12192262, 12192263, 12192264, 12192265, 12221005, 12225509, 12235017, 12361141819), the Chinese Academy of Sciences (CAS) Large-Scale Scientific Facility Program, the CAS Center for Excellence in Particle Physics (CCEPP), the Joint Large-Scale Scientific Facility Funds of the NSFC and CAS (U2032104, U1832207), the 100 Talents Program of CAS, the Excellent Youth Foundation of Henan Scientific Commitee (242300421044), the Institute of Nuclear and Particle Physics (INPAC) and Shanghai Key Laboratory for Particle Physics and Cosmology, the German Research Foundation DFG (FOR5327), the Istituto Nazionale di Fisica Nucleare, Italy, the Knut and Alice Wallenberg Foundation (2021.0174, 2021.0299), the Ministry of Development of Turkey (DPT2006K-120470), the National Research Foundation of Korea (NRF-2022R1A2C1092335), the National Science and Technology Fund of Mongolia, the National Science Research and Innovation Fund (NSRF) via the Program Management Unit for Human Resources & Institutional Development, Research, and Innovation of Thailand (B16F640076, B50G670107), the Polish National Science Center (2019/35/O/ST2/02907), the Swedish Research Council (2019.04595), the Swedish Foundation for International Cooperation in Research and Higher Education (CH2018-7756), and the US Department of Energy (DE-FG02-05ER41374).

We propose a numerical method to estimate one-point functions and the free-energy density of conformal field theories at finite temperature by solving the Kubo-Martin-Schwinger condition for the two-point functions of identical scalars. We apply the method for the critical <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="normal">O</mi><mo stretchy="false">(</mo><mi>N</mi><mo stretchy="false">)</mo></math> model for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>N</mi><mo>=</mo><mn>1</mn></math>, 2, 3 in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>3</mn><mo>≤</mo><mi>d</mi><mo>≤</mo><mn>4</mn></math>. We find agreement with known results from Monte Carlo simulations and previous results for the 3D Ising model, and we provide new predictions for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>N</mi><mo>=</mo><mn>2</mn></math>, 3.

Julien Barrat

United Kingdom

Enrico Marchetto

Alessio Miscioscia

Elli Pomoni

Thermal Bootstrap for the Critical <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi mathvariant="normal">O</mi><mo stretchy="false">(</mo><mi>N</mi><mo stretchy="false">)</mo></mrow></math> Model

We report on the first <italic>ab initio</italic> informed <italic>&#945;</italic> knock-out reaction in the intermediate-mass region, with the aim to probe the underlying chiral potential and its impact on the emergence of alpha clustering in this mass region. The theoretical predictions of the <math altimg='si1.svg'><mi>&#945;</mi><msup><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow><mrow><mn>16</mn></mrow></msup></math>O clustering in the 20Ne ground state, based on the <italic>ab initio</italic> symmetry-adapted no-core shell model with continuum, yield a triple differential cross section for 20Ne(p, p <italic>&#945;</italic>) 16O that is in a remarkable agreement with the data. This allows us to examine predictions of surface and in-medium <italic>&#945;</italic>-cluster features that emerge from the underlying realistic nucleon-nucleon interaction with no parameters fitted to nuclear data beyond the two-body system, and to compare these to the successful antisymmetrized molecular dynamics approach.

G.H. Sargsyan

Japan

Kazuki Yoshida

Kazuyuki Ogata

K.D. Launey

J.E. Escher

Czechia

D. Langr

T. Dytrych

<italic>Ab initio</italic> informed 20Ne(p, p <italic>&#945;</italic>) 16O reaction elucidates the emergence of alpha clustering from chiral potentials

We revisit the instanton partition function for 5d $$ \mathcal{N} $$ = 1 SO($\textit{N}$) gauge theories compactified on S , computed from the topological vertex formalism with the O-vertex based on a 5-brane web diagram with an O5-plane. We introduce an identity that enables us to rewrite the unrefined partition function into a new expression in terms of the Nekrasov factors summed over Young diagrams, which can be interpreted as the freezing of an O7-plane. Based on this, we propose topological vertex formalism with an O7 -plane.

Sung-Soo Kim

Xiaobin Li

Futoshi Yagi

Rui-Dong Zhu

O-vertex, O7

Recently the asymptotic lattice spacing dependence of spectral quantities in lattice QCD has been computed to $$\textrm{O}(a^2)$$ using Symanzik Effective theory (Husung et al. in Phys Lett B 829:137069, 2022; Husung in Eur Phys J C 83:142, 2023). Here, we extend these results to matrix elements and correlators of local fermion bilinears, namely the scalar, pseudo-scalar, vector, axial-vector, and tensor. This resembles the typical current insertions for the effective Hamiltonian of electro-weak or BSM contributions, but is only a small fraction of the local fields typically considered. We again restrict considerations to lattice QCD actions with Wilson or Ginsparg–Wilson quarks and thus lattice formulations of QCD without flavour-changing interactions realising at least $$\textrm{SU}(N_{\textrm{f}})_\textrm{V}\times \textrm{SU}(N_{\textrm{b}}|N_{\textrm{b}})_\textrm{V}$$ flavour symmetries for $$N_{\textrm{f}}$$ sea-quarks and $$N_{\textrm{b}}$$ quenched valence-quarks respectively in the massless limit. Overall we find only few cases $${\hat{\Gamma }}$$ , which worsen the asymptotic lattice spacing dependence $$a^n[2b_0{\bar{g}}^2(1/a)]^{{\hat{\Gamma }}}$$ compared to the classically expected $$a^n$$ -scaling. Other than for trivial flavour quantum numbers, only the axial-vector and much milder the tensor may cause some problems at $$\textrm{O}(a)$$ , strongly suggesting to use at least tree-level Symanzik improvement of those local fields.

Spain

Nikolai Husung

Lattice artifacts of local fermion bilinears up to $$\text {O}(\text {a}^2)$$

We investigate the heavy-quark expansion (HQE) for inclusive semileptonic $$ \overline{B} $$ decays, at tree level, by computing the fully differential decay rate up to order $$ \mathcal{O}\left({\Lambda}_{\textrm{QCD}}^5/{m}_b^5\right) $$ . We provide analytic results for the first three moments in the lepton energy, hadronic invariant mass and leptonic invariant mass ($\textit{q}$ ) with a lower cut on the lepton energy in the $$ \overline{B} $$ rest frame, as well as for the first three $\textit{q}$ moments with a lower cut on $\textit{q}$ . By means of the lowest-lying state saturation ansatz we study the numerical behaviour of the HQE providing insights into the theoretical error budget associated with power corrections. Available CLEO data on the second central $\textit{q}$ moment with a lower cut on the lepton energy present puzzling discrepancies with the theoretical expectations. This observation makes new measurements of these observables desirable, which could improve the precision of global fit analyses for the inclusive determination of |$\textit{V}$ |.

Gael Finauri

Kinematic moments of $$ \overline{B}\to {X}_c\ell {\overline{\nu}}_{\ell } $$ to order $$ \mathcal{O}\left({\Lambda}_{\textrm{QCD}}^5/{m}_b^5\right) $$

In this work, I consider N-component scalar quantum field theory in two dimensions interacting with an upside-down quartic potential. Working in the large N limit, the model can be solved non-perturbatively using the saddle-point method for sufficiently strong negative coupling. At high temperature, the O(N) model dimensionally reduces to $$ \mathcal{PT} $$ -symmetric quantum mechanics, for which powerful non-perturbative solution methods exist. It is found that the solution from quantum mechanics can be matched by the saddle-point method in quantum field theory when allowing for saddles beyond the principal Riemann sheet. I show that saddle points on non-principal Riemann sheets lead to a fully consistent solution of the 2d negative-coupling O(N) model for all temperatures.

Paul Romatschke

On the negative coupling O(N) model in 2d at high temperature