United States

Samuel Ting

Discovery of the J particle at Brookhaven National Laboratory and the physics of electrons and positrons

Cosmic strings are powerful witnesses to cosmic events including any period of early matter domination. If such a period of matter domination was catalyzed by metastable, long-lived particles, then there will be complementary signals to ascertain the nature of the dark sector in experiments detecting primordial features in the gravitational wave (GW) power spectrum and laboratory searches for long-lived particles. We give explicit examples of global and local <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>U</mi><mo stretchy="false">(</mo><mn>1</mn><mo stretchy="false">)</mo></math> gauge extended dark sectors to demonstrate such a complementarity as the union of the two experiments reveals more information about the dark sector than either experiment. Demanding that Higgs-portal long-lived scalar be looked for, in various experiments such as DUNE, FASER, FASER-II, MATHUSLA, and SHiP, we identify the parameter space that leads to complementary observables for GW detectors such as the Laser Interferometer Space Antenna and Einstein Telescope.

China

Satyabrata Datta

India

Ambar Ghosal

Poland

Anish Ghoshal

United Kingdom

Graham White

Complementarity between cosmic string gravitational waves and long-lived particle searches in a laboratory

Utilizing 4.5 $ \text{fb}^{-1} $ of $ e^+e^- $ annihilation data collected at center-of-mass energies ranging from 4599.53 MeV to 4698.82 MeV by the BESIII detector at the BEPCII collider, we searched for singly Cabibbo-suppressed hadronic decays $ \Lambda_{c}^{+}\to\Sigma^{0} K^{+}\pi^{0} $ and $ \Lambda_{c}^{+}\to\Sigma^{0}K^{+} \pi^+ \pi^- $ with a single-tag method. No significant signals were observed for both decays. The upper limits on the branching fractions at the 90% confidence level were determined to be $ 5.0\times 10^{-4} $ for $ \Lambda_{c}^{+}\to\Sigma^{0} K^{+}\pi^{0} $ and $ 6.5\times 10^{-4} $ for $ \Lambda_c^{+}\to\Sigma^0K^{+}\pi^{+}\pi^{-} $ .

M. Ablikim

Russia

M.N. Achasov

Sweden

P. Adlarson

X.C. Ai

Germany

R. Aliberti

Italy

A. Amoroso

Q. An

Y. Bai

O. Bakina

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

R.A. Briere

A. Brueggemann

H. Cai

M.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.K. Chen

S.K. Choi

X. Chu

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

Y.X. 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

G.F. Fan

J.J. Fan

Y.H. Fan

J. Fang

S.S. Fang

W.X. 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

Search for Cabibbo-suppressed decays ${\boldsymbol\Lambda_{\boldsymbol c}^{\bf +} }$ → Σ$^{0}$ $\textit{K}$ $^{+}$ $\textit{π}$ $^{0}$ and $ {\boldsymbol\Lambda_{\boldsymbol c}^{\bf +} }$ → Σ$^{0}$ $\textit{K}$ $^{+}$ $\textit{π}$ $^{+}$ $\textit{π}$ $^{−}$ * This study has been supported in part by National Key R&D Program of China (2020YFA0406300, 2020YFA0406400, 2023YFA1606000); National Natural Science Foundation of China (NSFC) (12205141, 11635010, 11735014, 11935015, 11935016, 11935018, 12025502, 12035009, 12035013, 12061131003, 12192260, 12192261, 12192262, 12192263, 12192264, 12192265, 12221005, 12225509, 12235017, 12361141819); Natural Science Foundation of Hunan Province (2024JJ2044); the Chinese Academy of Sciences (CAS) Large-Scale Scientific Facility Program; the CAS Center for Excellence in Particle Physics (CCEPP); Joint Large-Scale Scientific Facility Funds of the NSFC and CAS (U1832207); 100 Talents Program of CAS; The Institute of Nuclear and Particle Physics (INPAC) and Shanghai Key Laboratory for Particle Physics and Cosmology; German Research Foundation DFG (FOR5327); Istituto Nazionale di Fisica Nucleare, Italy; Knut and Alice Wallenberg Foundation (2021.0174, 2021.0299); Ministry of Development of Turkey (DPT2006K-120470); National Research Foundation of Korea (NRF-2022R1A2C1092335); National Science and Technology fund of Mongolia; National Science Research and Innovation Fund (NSRF) via the Program Management Unit for Human Resources & Institutional Development, Research and Innovation of Thailand (B16F640076, B50G670107); Polish National Science Centre (2019/35/O/ST2/02907); Swedish Research Council (2019.04595); The Swedish Foundation for International Cooperation in Research and Higher Education (CH2018-7756); and U. S. Department of Energy (DE-FG02-05ER41374)

We analyze the recent data from the BESIII collaboration on the $ X(3872) $ state in the $ J/\psi\pi^+\pi^- $ and $ D^0\bar{D}^0\pi^0 $ decay channels. The quantum number and mass of the $ X(3872) $ state allow us to exploit the universal feature of the very near-threshold $ D\bar D^* $ scattering in the $\textit{S}$ wave. The analysis of $ J/\psi\pi^+\pi^- $ and $ D^0\bar{D}^0\pi^0 $ data separately, as well as the combined analysis of these data together, all support the conclusion that $ X(3872) $ is an extremely weakly bound charm meson molecule.

Xian-Wei Kang

Jin-Zhe Zhang

Xin-Heng Guo

Nature of $\textit{X}$(3872) from recent BESIII data: considering the universal feature of an $\textit{S}$-wave threshold resonance * Supported by the National Natural Science Foundation of China (12275023)

The traditional Fermi function ansatz for nuclear beta decay describes enhanced perturbative effects in the limit of large nuclear charge <italic>Z</italic> and/or small electron velocity <italic>&#946;</italic>. We define and compute the quantum field theory object that replaces this ansatz for neutron beta decay, where neither of these limits hold. We present a new factorization formula that applies in the limit of small electron mass, analyze the components of this formula through two loop order, and resum perturbative corrections that are enhanced by large logarithms. We apply our results to the neutron lifetime, supplying the first two-loop input to the long-distance corrections. Our result can be summarized as <display><formula id='fm0010'><math altimg='si1.svg'><msub><mrow><mi>&#964;</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>&#215;</mo><mo stretchy='false'>|</mo><msub><mrow><mi>V</mi></mrow><mrow><mi>u</mi><mi>d</mi></mrow></msub><msup><mrow><mo stretchy='false'>|</mo></mrow><mrow><mn>2</mn></mrow></msup><mo stretchy='true' maxsize='2.4ex' minsize='2.4ex'>[</mo><mn>1</mn><mo linebreak='badbreak' linebreakstyle='after'>+</mo><mn>3</mn><msup><mrow><mi>&#955;</mi></mrow><mrow><mn>2</mn></mrow></msup><mo stretchy='true' maxsize='2.4ex' minsize='2.4ex'>]</mo><mo stretchy='true' maxsize='2.4ex' minsize='2.4ex'>[</mo><mn>1</mn><mo linebreak='badbreak' linebreakstyle='after'>+</mo><msub><mrow><mi mathvariant='normal'>&#916;</mi></mrow><mrow><mi>R</mi></mrow></msub><mo stretchy='true' maxsize='2.4ex' minsize='2.4ex'>]</mo><mo linebreak='badbreak' linebreakstyle='after'>=</mo><mfrac><mrow><mn>5263.284</mn><mo stretchy='false'>(</mo><mn>17</mn><mo stretchy='false'>)</mo><mspace width='0.2em' /><mi mathvariant='normal'>s</mi></mrow><mrow><mn>1</mn><mo linebreak='badbreak' linebreakstyle='after'>+</mo><mn>27.04</mn><mo stretchy='false'>(</mo><mn>7</mn><mo stretchy='false'>)</mo><mo>&#215;</mo><msup><mrow><mn>10</mn></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>&#8722;</mo><mn>3</mn></mrow></msup></mrow></mfrac><mspace width='0.25em' /><mo>,</mo></math></formula></display> with <math altimg='si2.svg'><mo stretchy='false'>|</mo><msub><mrow><mi>V</mi></mrow><mrow><mi>u</mi><mi>d</mi></mrow></msub><mo stretchy='false'>|</mo></math> the up-down quark mixing parameter, <math altimg='si3.svg'><msub><mrow><mi>&#964;</mi></mrow><mrow><mi>n</mi></mrow></msub></math> the neutron's lifetime, <italic>&#955;</italic> the ratio of axial to vector charge, and <math altimg='si4.svg'><msub><mrow><mi mathvariant='normal'>&#916;</mi></mrow><mrow><mi>R</mi></mrow></msub></math> the short-distance matching correction. We find a shift in the long-distance radiative corrections compared to previous work, and discuss implications for extractions of <math altimg='si2.svg'><mo stretchy='false'>|</mo><msub><mrow><mi>V</mi></mrow><mrow><mi>u</mi><mi>d</mi></mrow></msub><mo stretchy='false'>|</mo></math> and tests of the Standard Model.

Peter Vander Griend

Zehua Cao

Richard J. Hill

Ryan Plestid

The Fermi function and the neutron's lifetime

We present the first detailed study of Standard Model neutrino tridents involving tau leptons at the near detectors of accelerator neutrino facilities. The rates of these processes were previously thought to be negligible, even at future facilities. Our full <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>2</mn><mo stretchy="false">→</mo><mn>4</mn></math> calculation, including both coherent and incoherent scatterings, reveals that the DUNE near detector could observe a considerable number of tau tridents—an important background to new physics searches. We identify promising kinematic features that may allow distinction of tau tridents from the usual neutrino charged-current background at DUNE, and thus establish the observation of tau tridents for the first time. We also comment on the detection prospects at other accelerator and collider neutrino experiments.

Innes Bigaran

P.S. Bhupal Dev

Diego Lopez Gutierrez

Pedro A.N. Machado

Tau tridents at accelerator neutrino facilities

We determine the chiral vortical conductivities, as well as the orbital and spin moment of inertia of a charged, chiral, and rigidly rotating free Fermi gas. To this purpose, we begin by calculating the vacuum expectation values of a vector and axial vector current using the free fermion propagator in this medium. This propagator is derived by employing the Fock-Schwinger method based on the solutions of the Dirac equation in the presence of rotation and finite axial chemical potential. We present a complete derivation of these solutions. We demonstrate that in the first approximation, the chiral vortical conductivity associated with the vector current is proportional to the product of the vector and axial chemical potentials. In contrast, the chiral vortical conductivity related to the axial vector current depends on the temperature, the vector, and the axial vector chemical potential squares. We use the relation between the axial vector current and the angular momentum density associated with spin to determine the spin and the orbital moment of inertia of a rigidly rotating Fermi gas in a charged and chirally imbalanced medium separately. In addition, we compute the total moment of inertia by utilizing the methods presented in the first part of the paper and show that the orbital moment of inertia of a free fermion gas vanishes.

Iran

M. Abedlou Ahadi

N. Sadooghi

Chiral vortical conductivities and the moment of inertia of a rigidly rotating Fermi gas

A geometric interpretation for an algebraic interacting boson-fermion model with configuration mixing is presented. The formalism is based on an extended Bose-Fermi matrix coherent states and is applied to gain insight on intertwined quantum shape-phase transitions and shape coexistence in odd-mass Nb nuclei.

Israel

A. Leviatan

N. Gavrielov

Geometry of configuration mixing in Bose-Fermi systems

Correlation $ \chi^{BQ}_{11} $ and quadratic fluctuations $ \chi^B_2,\ \chi^Q_2,\ \chi^T_2 $ of baryon number $\textit{B}$, electric charge $\textit{Q,}$ and temperature $\textit{T}$ are investigated in a two-flavor Polyakov loop extended Nambu-Jona-Lasinio (PNJL) model at finite temperature and magnetic field. The inverse magnetic catalysis (IMC) effect is introduced through magnetic-field-dependent parameters $ G(eB) $ and $ T_0(eB) $ , and we compare the results in scenarios with and without the IMC effect. Under a nonvanishing magnetic field, correlation $ \chi^{BQ}_{11} $ and fluctuations $ \chi^B_2,\ \chi^Q_2,\ \chi^T_2 $ increase with temperature and then exhibit a peak around the pseudocritical temperatures of chiral restoration and deconfinement phase transitions in the cases with and without the IMC effect. The correlation and fluctuations along the phase transition line under an external magnetic field are characterized by scaled correlation ${\hat {\chi}}_{11}^{BQ}={\chi_{11}^{BQ}(eB,T_{pc}^c(eB))}/{\chi_{11}^{BQ}(eB=0,T_{pc}^c(eB=0))}$ and scaled fluctuations ${\hat {\chi}}_2^{B(Q,T)}={\chi_2^{B(Q,T)}(eB,T_{pc}^c(eB))}/{\chi_2^{B(Q,T)}(eB=0,T_{pc}^c(eB=0))}$ at pseudocritical temperature $ T_{pc}^c $ of chiral restoration phase transition. $ {\hat {\chi}}_{11}^{BQ},\ {\hat {\chi}}_2^{B} $ , and $ {\hat {\chi}}_2^{Q} $ increase with the magnetic field, and the inclusion of the IMC effect enhances their values somewhat. However, $ {\hat {\chi}}_2^{T} $ is altered by the IMC effect. Without the IMC effect, $ {\hat \chi}^T_2 $ increases slightly and then decreases with the magnetic field. Considering the IMC effect using $ G(eB) $ , $ {\hat \chi}^T_2 $ monotonically increases with the magnetic field, and that using $ T_0(eB) $ is a nonmonotonic function of the magnetic field.

Shijun Mao

Correlations and fluctuations in a magnetized PNJL model with and without the inverse magnetic catalysis effect * Supported by the National Natural Science Foundation of China (12275204)

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.

O. Afedulidis

I. Balossino

Z.Y. Chen

Y. Fang

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).