<p>We investigate the semileptonic decays of charmed mesons to light vector mesons within the framework of light-cone sum rules. Our calculation is performed at leading order in quantum chromodynamics (QCD) coupling, incorporating contributions up to twist-five accuracy from both two-particle and three-particle light-cone distribution amplitudes. Transition form factors are predicted twist by twist to assess the convergence property of the operator product expansion. It is verified that the twist-four and twist-five contributions are indeed negligible for all the decays under consideration. Twist-three dominance is observed for some of the form factors, subject to heavy quark effective field theory interpretation. Branching ratios for the decays <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mo>+</mo></msup><mo stretchy="false">→</mo><msup><mi>ρ</mi><mn>0</mn></msup><msup><mo>ℓ</mo><mo>+</mo></msup><msub><mi>ν</mi><mo>ℓ</mo></msub></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>D</mi><mi>s</mi><mo>+</mo></msubsup><mo stretchy="false">→</mo><msup><mi>K</mi><mrow><mo>*</mo><mn>0</mn></mrow></msup><msup><mo>ℓ</mo><mo>+</mo></msup><msub><mi>ν</mi><mo>ℓ</mo></msub></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mn>0</mn></msup><mo stretchy="false">→</mo><msup><mi>K</mi><mrow><mo>*</mo><mo>−</mo></mrow></msup><msup><mo>ℓ</mo><mo>+</mo></msup><msub><mi>ν</mi><mo>ℓ</mo></msub></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mo>+</mo></msup><mo stretchy="false">→</mo><msup><mover accent="true"><mi>K</mi><mo stretchy="false">¯</mo></mover><mrow><mo>*</mo><mn>0</mn></mrow></msup><msup><mo>ℓ</mo><mo>+</mo></msup><msub><mi>ν</mi><mo>ℓ</mo></msub></math> are obtained, and a 10%–20% discrepancy from experimental measurements is found. Our finding indicates that the resonant-width and nonresonant QCD backgrounds effects should be potentially significant, implying the necessity to further implement their contributions in future precision studies of the semileptonic charm decays.</p>

China

Wang Lin

Xiao-En Huang

Shan Cheng

De-Liang Yao

Semileptonic decays of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>D</mi><mo stretchy="false">→</mo><mi>ρ</mi><msup><mi>l</mi><mo>+</mo></msup><mi>ν</mi></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>D</mi><mrow><mo stretchy="false">(</mo><mi>s</mi><mo stretchy="false">)</mo></mrow></msub><mo stretchy="false">→</mo><msup><mi>K</mi><mo>*</mo></msup><msup><mi>l</mi><mo>+</mo></msup><mi>ν</mi></math> from light-cone sum rules

Compared with the Poincaré braneworld, the de Sitter (dS) braneworld aligns more closely with the present universe characterized by a small but finite cosmological constant. To explore the quasinormal ringing properties within the dS brane scenario, we investigate the gravitational perturbations in both thin and thick dS brane configurations. Analysis of the perturbation equations reveals that the effective potential along the extra dimension exhibits the shape of Pöschl-Teller potential, asymptotically approaching a constant value (mass gap) at infinity. In particular, this mass gap can be reduced. And analytical calculations further indicate that the gravitational perturbations, apart from the zero mode, possess a series of discrete, purely imaginary quasinormal modes in the late stages. This result implies that these perturbations decay without oscillation over time. The analytical findings also demonstrate that the brane structure primarily determines the distribution of the quasinormal spectrum while preserving the purely imaginary nature of the quasinormal frequencies. Subsequently, we further simulate the gravitational wave signal by numerically evolving the perturbation equations, which yield late-stage results consistent with the analytical predictions. Interestingly, these quasinormal modes carry information about the cosmological constant on the brane, which provides a potential new pathway for the study of cosmology in the dS brane scenario.

Hai-Long Jia

Wen-Di Guo

Yu-Xiao Liu

Qin Tan

Quasinormal ringing of de Sitter braneworlds

<p>We advance the study of pure de Sitter supergravity by introducing a finite formulation of unimodular supergravity via the super-Stückelberg mechanism. Building on previous works, we construct a complete four-dimensional action of spontaneously broken <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">N</mi><mo>=</mo><mn>1</mn></math> supergravity to all orders in the Stückelberg fields, which allows for de Sitter solutions. The introduction of finite supergravity transformations extends the super-Stückelberg procedure beyond the second order, offering a recursive solution to all orders in the Goldstino sector. This work bridges the earlier perturbative approaches and the complete finite theory, opening new possibilities for de Sitter vacua in supergravity models and eventually string theory.</p>

Austria

Sukṛti Bansal

United Kingdom

Silvia Nagy

Antonio Padilla

Ivonne Zavala

Stückelberg path to pure de Sitter supergravity

The 1 + 3-de Sitter space, as a solution of Einstein’s equations, provides a framework for investigating various physical concepts, including quantum mechanics. In this context, the group Sp(2,2) plays a crucial role as the universal covering of the de Sitter space, contributing significantly to the understanding of associated quantum mechanics. In this study, the presentation of infinitesimal generators of the group Sp(2,2) and quantum operators on the de Sitter space is conducted using the coherent states quantization method, also known as Berezin’s quantization method. This approach allows for a systematic examination of the generators and operators within the quantum framework. Furthermore, the exploration of these generators and operators is facilitated by the unitary representation of the principal series of the group Sp(2,2), offering insights into the underlying quantum mechanics principles governing the de Sitter space.

Iran

A. Rabeie

Infinitesimal generators and quantum operators in de Sitter space

Jackiw-Teitelboim (JT) gravity in two-dimensional de Sitter space is an intriguing model for cosmological “wave functions of the universe”. Its minisuperspace version already contains all physical information. The size of compact slices is parametrized by a scale factor $\textit{h}$ > 0. The dilaton $\textit{ϕ}$ is chosen to have positive values and interpreted as size of an additional compact slice in a higher-dimensional theory. At the boundaries $\textit{h}$ = 0, $\textit{ϕ}$ = 0, where the volume of the universe vanishes, the curvature is generically singular. According to a conjecture by DeWitt, solutions of the Wheeler-DeWitt (WDW) equation should vanish at singular loci. Recently, the behaviour of JT wave functions at large field values $\textit{h}$, $\textit{ϕ}$ has been obtained by means of a path integral over Schwarzian degrees of freedom of a boundary curve. We systematically analyze solutions of the WDW equation with Schwarzian asymptotic behaviour. We find real analytic solutions that vanish on the entire boundary, in agreement with DeWitt’s conjecture. Projection to expanding and contracting branches may lead to singularities, which can however be avoided by an appropriate superposition of solutions. Our analysis also illustrates the limitations of semiclassical wave functions.

Germany

Wilfried Buchmüller

Arthur Hebecker

Alexander Westphal

DeWitt wave functions for de Sitter JT gravity

We revisit duality-covariant higher-derivative corrections which arise from the generalized Bergshoeff-de Roo (gBdR) identification, a prescription that gives rise to a two parameter family of $\textit{α}$ -corrections to the low-energy effective action of the bosonic and the heterotic string. Although it is able to reproduce all corrections at the leading and sub-leading ($\textit{α}$ ) order purely from symmetry considerations, a geometric interpretation, like for the two-derivative action and its gauge transformation is lacking. To address this issue and to pave the way for the future exploration of higher-derivative (=higher-loop for the $\textit{β}$-functions of the underlying $\textit{σ}$-model) corrections to generalized dualities, consistent truncations and integrable $\textit{σ}$-models, we recover the gBdR identification’s results from the Poláček-Siegel construction that provides a natural notion of torsion and curvature in generalized geometry.

Poland

Achilleas Gitsis

Falk Hassler

Unraveling the generalized Bergshoeff-de Roo identification

Israel

Riccardo Ciccone

Italy

Fabiana Cesare

Lorenzo Pietro

Marco Serone

Erratum: Exploring confinement in Anti-de Sitter space

We revisit the problem of the thermalization process for an Unruh-DeWitt (UDW) detector in de Sitter space. We derive the complete dynamics of the detector in the context of an open quantum system, without utilizing Markovian or RWA approximations. We employ quantum Fisher information (QFI) to estimate the Hubble parameter, which serves as a process function to distinguish the thermalization paths in the detector’s Hilbert space, determined by its local properties, including the detector’s energy gap and its initial state preparation, or by the global spacetime geometry. We find that the non-Markovian contribution generally reduces the QFI compared to the Markovian approximated solution. Regarding arbitrary initial states, the late-time QFI converges to an asymptotic value. In particular, we are interested in the background field within the one-parameter family of α-vacua in de Sitter space. We show that for general choices of $\textit{α}$-vacuum, the asymptotic values of the converged QFI are significantly suppressed compared to previously known results for the Bunch-Davies vacuum.

Langxuan Chen

Jun Feng

Quantum Fisher information of a cosmic qubit undergoing non-Markovian de Sitter evolution

We give the connection formulae for ordinary differential equations with 5 and 6 (and in principle can be generalized to more) regular singularities from the data of instanton partition functions of quiver gauge theories. We check the consistency of these connection formulae by numerically computing the quasinormal modes (QNMs) of Reissner-Nordström de Sitter (RN-dS) blackhole. Analytic expressions are obtained for all the families of QNMs, including the photon-sphere modes, dS modes, and near-extremal modes. We also argue that a similar method can be applied to the dS-Kerr-Newman blackhole.

Pujun Liu

Rui-Dong Zhu

Notes on quasinormal modes of charged de Sitter blackholes from quiver gauge theories

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.

M. Ablikim

Russia

M.N. Achasov

Sweden

P. Adlarson

O. Afedulidis

X.C. Ai

R. Aliberti

A. Amoroso

Q. An

Y. Bai

O. Bakina

I. Balossino

Y. Ban

H.R. Bao

V. Batozskaya

Mongolia

K. Begzsuren

N. Berger

M. Berlowski

M. Bertani

D. Bettoni

F. Bianchi

E. Bianco

A. Bortone

I. Boyko

United States

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).