Numerous studies have demonstrated that the phenomenological optical potential of tightly bound nuclear systems presents a threshold anomaly phenomenon in the near-Coulomb barrier energy region, where the relationship between the real and imaginary potentials can be well described by the dispersion relation. However, for some weakly bound nuclear systems, the phenomenological optical potential seems to manifest differently, and the dispersion relation struggles to describe the behavior between real and imaginary potentials. Recently, we measured the angular distributions of the transfer reaction Pb-207(Li-7,Li-6)Pb-208 in both near and deep barrier energy regions, as well as the elastic scattering angular distributions of the entrance channel Li-7+Pb-207. Optical potentials of the Li-6+Pb-208 system were extracted. The current results indicate that the optical potentials exhibit an abnormal threshold anomaly, and the dispersion relation is not applicable. Possible explanations are discussed, yet further investigations into the underlying physics are required.

The full data set of the Daya Bay reactor neutrino experiment is used to probe the effect of the charged current non-standard interactions (CC-NSI) on neutrino oscillation experiments. Two different approaches are applied and constraints on the corresponding CC-NSI parameters are obtained with the neutrino flux taken from the Huber-Mueller model with a $5\%$ uncertainty. For the quantum mechanics-based approach (QM-NSI), the constraints on the CC-NSI parameters $\epsilon_{e\alpha}$ and $\epsilon_{e\alpha}^{s}$ are extracted with and without the assumption that the effects of the new physics are the same in the production and detection processes, respectively. The approach based on the weak effective field theory (WEFT-NSI) deals with four types of CC-NSI represented by the parameters $[\varepsilon_{X}]_{e\alpha}$. For both approaches, the results for the CC-NSI parameters are shown for cases with various fixed values of the CC-NSI and the Dirac CP-violating phases, and when they are allowed to vary freely. We find that constraints on the QM-NSI parameters $\epsilon_{e\alpha}$ and $\epsilon_{e\alpha}^{s}$ from the Daya Bay experiment alone can reach the order $\mathcal{O}(0.01)$ for the former and $\mathcal{O}(0.1)$ for the latter, while for WEFT-NSI parameters $[\varepsilon_{X}]_{e\alpha}$, we obtain $\mathcal{O}(0.1)$ for both cases.

This work briefly introduces our recent studies on reactions induced by proton drip-line nuclei, B-8 and F-17, at energies around the Coulomb barrier. Using detector arrays with large solid-angle coverage, the complete kinematics measurements were performed for systems of B-8+Sn-120 and F-17+Ni-58. For the B-8+Sn-120, the coincident measurement of the breakup fragments was achieved for the first time for a proton-halo nuclear system. The correlations between the breakup fragments reveal that the prompt breakup occurring on the outgoing trajectory dominates the breakup dynamics of B-8. For F-17+Ni-58, the complete reaction channel information, such as quasi-elastic scattering, breakup and total fusion, was derived for the first time. An enhancement of the fusion cross section of F-17+Ni-58 was observed at the energy below the Coulomb barrier. Theoretical calculations indicate that this phenomenon is mainly due to the couplings to the continuum states. Moreover, different direct reaction dynamics were found in B-8 and F-17 systems, suggesting the influence of proton-halo structure on the reaction dynamics.

Data for the angular distribution of the inclusive 7 Be production cross section in the 8 B + 208 Pb system at an incident energy of 50 MeV, equivalent to the nominal Coulomb barrier height, were measured at the CRIB facility. A coupled discretized continuum channel calculation was able to describe the data well, with no evidence for a significant contribution from nonelastic breakup. The energy dependence of the breakup cross section was investigated with the aid of previous measurements of the inclusive 7 Be production cross section for the same system at a deep sub-barrier energy and at approximately four times the Coulomb barrier. We infer an increasing importance of nonelastic breakup as the incident energy is increased above the barrier, ruling out proton-stripping as a possible mechanism for this process due to the increasingly badly Q-matched character of this transfer reaction as the incident energy increases.

The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 2,717 new measurements from 869 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as supersymmetric particles, heavy bosons, axions, dark photons, etc. Particle properties and search limits are listed in Summary Tables. We give numerous tables, figures, formulae, and reviews of topics such as Higgs Boson Physics, Supersymmetry, Grand Unified Theories, Neutrino Mixing, Dark Energy, Dark Matter, Cosmology, Particle Detectors, Colliders, Probability and Statistics. Most of the 120 reviews are updated, including many that are heavily revised. The Review is divided into two volumes. Volume 1 includes the Summary Tables and 97 review articles. Volume 2 consists of the Particle Listings and contains also 23 reviews that address specific aspects of the data presented in the Listings. The complete Review (both volumes) is published online on the website of the Particle Data Group (pdg.lbl.gov) and in a journal. Volume 1 is available in print as the PDG Book. A Particle Physics Booklet with the Summary Tables and essential tables, figures, and equations from selected review articles is available in print, as a web version optimized for use on phones, and as an Android app.

Daya Bay presents the first measurement of cosmogenic He-8 isotope production in liquid scintillator, using an innovative method for identifying cascade decays of He-8 and its child isotope, Li-8. We also measure the production yield of Li-9 isotopes using well-established methodology. The results, in units of 10(-8)mu-1g(-1) cm(2), are 0.307 +/- 0.042, 0.341 +/- 0.040, and 0.546 +/- 0.076 for He-8, and 6.73 +/- 0.73, 6.75 +/- 0.70, and 13.74 +/- 0.82 for 9Li at average muon energies of 63.9 GeV, 64.7 GeV, and 143.0 GeV, respectively. The measured production rate of He-8 isotopes is more than an order of magnitude lower than any other measurement of cosmogenic isotope production. It replaces the results of previous attempts to determine the ratio of He-8 to Li-9 production that yielded a wide range of limits from 0% to 30%. The results provide future liquid-scintillator-based experiments with improved ability to predict cosmogenic backgrounds.

This Letter reports the first measurement of the oscillation amplitude and frequency of reactor antineutrinos at Daya Bay via neutron capture on hydrogen using 1958 days of data. With over 3.6 million signal candidates, an optimized candidate selection, improved treatment of backgrounds and efficiencies, refined energy calibration, and an energy response model for the capture-on-hydrogen sensitive region, the relative ν[over ¯]_{e} rates and energy spectra variation among the near and far detectors gives sin^{2}2θ_{13}=0.0759_{-0.0049}^{+0.0050} and Δm_{32}^{2}=(2.72_{-0.15}^{+0.14})×10^{-3}  eV^{2} assuming the normal neutrino mass ordering, and Δm_{32}^{2}=(-2.83_{-0.14}^{+0.15})×10^{-3}  eV^{2} for the inverted neutrino mass ordering. This estimate of sin^{2}2θ_{13} is consistent with and essentially independent from the one obtained using the capture-on-gadolinium sample at Daya Bay. The combination of these two results yields sin^{2}2θ_{13}=0.0833±0.0022, which represents an 8% relative improvement in precision regarding the Daya Bay full 3158-day capture-on-gadolinium result.

Reactions of weakly bound stable and unstable nuclei have been extensively investigated for several decades. Unique structural effects and breakup mechanisms of weakly bound nuclei have consistently been focal points in the research of nuclear physics, especially at energies around the Coulomb barrier. This paper will review the recent experimental researches performed by the Nuclear Reaction Group at the China Institute of Atomic Energy on weakly bound nuclear reactions in the near-barrier energy region. A anomalous threshold phenomenon in the optical potentials of the 6He + 208Bi system has been observed. Results indicate that the dispersion relation cannot describe the relation between the real part and imaginary part of the optical potential. Moreover, breakup mechanisms of stable weakly bound nuclei 6,7Li as well as proton-rich nuclei 17F and 8B have been studied. The similarities and differences in breakup mechanisms and their effects are discussed.

Quantum mechanics serves as the fundamental cornerstone for numerous areas of research. Finding simple and analytical quantum transmission coefficients for potentials is a rare occurrence. Notably, we have discovered a readily provable yet unreported symmetry tunneling law. For an infinite parabolic potential, it can be proved analytically that the sum of the one-dimensional tunneling probabilities at incident energies equal to the barrier height plus or minus any energy deviation is consistently 1. Based on this relationship, the original WKB approximation and the Kemble's formula can be generalized to the above-barrier energy region in a simplified but more accurate manner, referred to as the symmetric WKB approach in this context. For the realistic potential between two nuclei, numerical results demonstrate that the symmetry relationship at the above-barrier energy region and the sub-barrier energy is also well satisfied, as well as in the cases of the multichannel WKB method. The symmetry tunneling law has been effectively extended to the Eckart potential as well. Such symmetry in tunneling may have universal characteristics but its underlying reason remains to be uncovered, which may help us to further understand the quantum mechanisms.

Multinucleon transfer (MNT) reactions have received increasing interest in the synthesis of neutron-rich nuclei due to the distinct limitations of other reactions, particularly in the N = 126 region, which represents the last waiting point of astrophysical nucleosynthesis. However, it is still a challenging endeavor to describe the MNT process between heavy nuclei. In this study, we develop a theoretical framework that couples the Langevin dynamics iteratively with the master equation, which is based on the HICOL model (CLIM-H). The random transfer process is achieved by solving the master equation using the Monte Carlo method, where the parametric transfer probability with a Q window is employed. The isotope distributions for 58,64Ni+208Pb, as well as the angular and isotope distributions of the recently measured 206Pb + 118Sn, could be generally reproduced based on this method. Contrary to previous theoretical predictions which show a high production cross section of N = 126 nuclei, current calculations do not reveal appreciable cross sections. The distinguishing characteristic of this approach is its ability to generate not only the mass distribution but also the charge distribution self-consistently, which could provide references for many other studies using the multidimensional Langevin equation considering only the mass asymmetry degree of freedom.

This Letter presents results of a search for the mixing of a sub-eV sterile neutrino with three active neutrinos based on the full data sample of the Daya Bay Reactor Neutrino Experiment, collected during 3158 days of detector operation, which contains 5.55×10^{6} reactor ν[over ¯]_{e} candidates identified as inverse beta-decay interactions followed by neutron capture on gadolinium. The analysis benefits from a doubling of the statistics of our previous result and from improvements of several important systematic uncertainties. No significant oscillation due to mixing of a sub-eV sterile neutrino with active neutrinos was found. Exclusion limits are set by both Feldman-Cousins and CLs methods. Light sterile neutrino mixing with sin^{2}2θ_{14}≳0.01 can be excluded at 95% confidence level in the region of 0.01  eV^{2}≲|Δm_{41}^{2}|≲0.1  eV^{2}. This result represents the world-leading constraints in the region of 2×10^{-4}  eV^{2}≲|Δm_{41}^{2}|≲0.2  eV^{2}.

We present a new determination of the smallest neutrino mixing angle θ_{13} and the mass-squared difference Δm_{32}^{2} using a final sample of 5.55×10^{6} inverse beta-decay (IBD) candidates with the final-state neutron captured on gadolinium. This sample is selected from the complete dataset obtained by the Daya Bay reactor neutrino experiment in 3158 days of operation. Compared to the previous Daya Bay results, selection of IBD candidates has been optimized, energy calibration refined, and treatment of backgrounds further improved. The resulting oscillation parameters are sin^{2}2θ_{13}=0.0851±0.0024, Δm_{32}^{2}=(2.466±0.060)×10^{-3}  eV^{2} for the normal mass ordering or Δm_{32}^{2}=-(2.571±0.060)×10^{-3}  eV^{2} for the inverted mass ordering.

We present an original algorithm in the MAPLE system for solving the scattering problem in single-channel approximation of the coupled-channel method of the optical model (OM) described by a second-order ordinary differential equation (ODE) with a complex-valued potential and regular boundary conditions. The complex-valued potential consists of the known real part, which is a sum of the nuclear potential, the Coulomb potential, and the centrifugal potential, and the imaginary part, which is a product of the unknown coupling constant g ( E ), depending on the collision energy E of a pair of ions, and the derivative of the real part of the known nuclear potential with respect to the ODE independent variable. The presented algorithm implements the solution of the inverse problem, i.e., calculates the unknown coupling constant g ( E ) and scattering matrix S ( g ( E ), E ) from condition | S ( g ( E ) , E ) | 2 = 1 - | T ( E ) | 2 by means of the secant method. The required amplitudes of transmission T ( E ) and reflection R ( E ) subject also to the condition | R ( E ) | 2 = 1 - | T ( E ) | 2 of the model with incoming wave boundary conditions (IWBCs) are previously calculated by the standard MAPLE implemented KANTBP 4M program. The algorithm provides a one-to-one correspondence between the OM with a complex-valued potential and the model of IWBCs with a real-valued potential. The efficiency of the proposed approach is shown by solving numerically the scattering problem and calculating the reference fusion cross section for a pair of heavy ions 16 O+ 144 Sm in the single-channel approximation of the close-coupling method.

The & alpha; decay of 222U was reinvestigated using a general least-square superpulse fitting algorithm dedicated to resolving pileup signals in the decay of very short-lived nuclei. The & alpha;-particle energy of 222U was revised to be 9246(8) keV, and the precision was improved significantly compared with previous result. Using the present & alpha; energy, the anomaly in the systematics of the & alpha;-decay reduced width 82 observed at 222U in the NpNn scheme is solved, all the 82 values converge into a smooth and narrow band with NpNn up to & AP;90 in the northeast of 208Pb.

The present work provides a literature survey of breakup reactions induced by weakly bound nuclei at energies around the Coulomb barrier. We review the inclusive and exclusive breakup data of stable weakly bound nuclei 6,7Li and 9Be, as well as light radioactive projectiles reported within the last decade. Several theoretical and data analysis tools used to describe the data are reviewed as well. Similarities and differences in the behavior of breakup reactions involving these weakly bound nuclei are discussed. It is found that, for 6,7Li and 9Be, transfer-triggered breakup is a significant mode, which, however, is not observed in drip-line nuclear systems. Moreover, differences in the breakup dynamics and the contribution of breakup to the total reaction cross section at energies close to the Coulomb barrier seem to emerge between neutron-halo and proton-halo systems. Possible explanations for the observed differences are discussed.

A FORTRAN program for calculating energy values, reflection and transmission matrices, and corresponding wave functions in a coupled-channel approximation of the adiabatic approach is presented. In this approach, a multidimensional Schrodinger equation is reduced to a system of the coupled second-order ordinary differential equations on a finite interval with the homogeneous boundary conditions of the third type at left- and right-boundary points for the discrete spectrum and scattering problems. The resulting system of such equations, containing potential matrix elements and first-derivative coupling terms is solved using high-order accuracy approximations of the finite element method. The scattering problem is solved with non-diagonal potential matrix elements in the left and/or right asymptotic regions and different left and right threshold values. Benchmark calculations for the fusion cross sections of S-36+Ca-48, Ni-64+Mo-100 reactions are presented. As a test desk, the program is applied to the calculation of the reflection and transmission matrices and corresponding wave functions of the exact solvable wave-guide model, and also the fusion cross sections and mean angular momenta of the O-16+Sm-144 reaction. Program summary Program Title: KANTBP CPC Library link to program files: https://doi.org/10.17632/4vm9fhyvh3.1 Licensing provisions: CC BY NC 3.0 Programming language: FORTRAN Nature of problem: In the adiabatic approach [1], a multidimensional Schrodinger equation for quantum reflection [2], the photoionization and recombination of a hydrogen atom in a homogeneous magnetic field [3-6], the three-dimensional tunneling of a diatomic molecule incident upon a potential barrier [7], wave-guide models [8], the fusion model of the collision of heavy ions [9-11], and low-energy fusion reactions of light- and medium mass nuclei [12] is reduced by separating the longitudinal coordinate, labeled as z, from transversal variables to a system of second-order ordinary differential equations containing the potential matrix elements and first-derivative coupling terms. The purpose of this paper is to present a program based on the use of high-order accuracy approximations of the finite element method (FEM) for calculating energy levels, reflection and transmission matrices and wave functions for such systems of coupled-channel second order differential equations (CCSODEs) on finite intervals of the variable z is an element of [Z(min), Z(max)] with homogeneous boundary conditions of the third-type at the left- and right-boundary points, which follow from the discrete spectrum and scattering problems. Solution method: The boundary-value problems for the system of CCSODEs are solved by the FEM using high-order accuracy approximations [13,14]. The generalized algebraic eigenvalue problem AF = E B F with respect to pair unknowns (E, F), arising after the replacement of the differential eigenvalue problem by the finite-element approximation, is solved by the subspace iteration method [14]. The generalized algebraic eigenvalue problem of a special form (A - E B) F = D F with respect to pair unknowns (D, F) arising after the corresponding replacement of the scattering boundary problem in open channels at fixed energy value, E, is solved by the LD L-T factorization of the symmetric matrix and back-substitution methods [14]. Additional comments including restrictions and unusual features: The user must supply subroutine POTCAL for evaluating potential matrix elements. The user should also supply subroutines ASYMEV (when solving the eigenvalue problem) or ASYMSL and ASYMSR (when solving the scattering problem) which evaluate asymptotics of the wave functions at boundary points in the case of a boundary conditions of the third-type for the above problems. (C) 2022 Elsevier B.V. All rights reserved.

β decay of proton-rich nuclei plays an important role in exploring isospin mixing. The β decay of ^{26}P at the proton drip line is studied using double-sided silicon strip detectors operating in conjunction with high-purity germanium detectors. The T=2 isobaric analog state (IAS) at 13 055 keV and two new high-lying states at 13 380 and 11 912 keV in ^{26}Si are unambiguously identified through β-delayed two-proton emission (β2p). Angular correlations of two protons emitted from ^{26}Si excited states populated by ^{26}P β decay are measured, which suggests that the two protons are emitted mainly sequentially. We report the first observation of a strongly isospin-mixed doublet that deexcites mainly via two-proton decay. The isospin mixing matrix element between the ^{26}Si IAS and the nearby 13 380-keV state is determined to be 130(21) keV, and this result represents the strongest mixing, highest excitation energy, and largest level spacing of a doublet ever observed in β-decay experiments.

The second and final version of ColdADC, called ColdADC_P2, is presented. ColdADC_P2 is a 16-channel, 12-bit, 2 MS/s digitizer application-specific integrated circuit (ASIC) intended for use inside the DUNE Far Detector. ColdADC_P2 contains two 16 MS/s pipelined analog-to-digital converters (ADCs) that each digitizes the output of eight sample-and-hold amplifiers (SHAs). Because the application requires immersion in liquid argon (LAr), ColdADC_P2 was developed using specialized design techniques for long-term reliability in cryogenic environments and a customized cryogenic standard cell library. ColdADC_P2, with a die area of approximately 52.4 mm2 and fabricated in 65-nm CMOS technology, achieves 130- $\mu \text{V}$ rms noise performance and 11.8-bit effective-number-of-bits (ENOB) at a temperature of 77 K, with channel-to-channel crosstalk of < 0.06% while dissipating 338 mW (21 mW per channel). Residual nonlinearity that is consistent with dielectric absorption in the capacitors internal to the ADC is corrected using a lookup table.

Background: To understand superheavy element synthesis reactions, quantifying the role of quantum shells in quasifission dynamics is important. In reactions with actinide nuclides, a wide peak in the binary quasifission mass yield is seen, centered close to the 208Pb mass. It is generally attributed to the 208Pb spherical closed shells causing a valley in the potential-energy surface, attracting flux to these mass splits. However, an early experiment studying 48Ca, 50Ti+238U reactions showed strong evidence that sequential fission plays an important role in generating the observed peak. These conflicting interpretations have not been resolved up to now.Purpose: This work aims to measure quasifission mass spectra for reactions with nuclei lighter than 208Pb, having negligible sequential fission, to search for systematic features correlated with the proton shells known to affect low-energy fission mass distributions of the same actinide elements.Methods: Systematic measurements have been made at energies near and below the capture barriers (where quasifission is most prominent) of mass-angle distributions for fission following collisions of 48Ti projectiles with even-even nuclides from 154Sm to 200Hg. Mean excitation energies above the ground-states ranged from 51 to 33 MeV, respectively.Results: With increasing compound nucleus atomic number ZCN, a rapid transition occurs from fission having characteristics of fusion-fission to fast quasifission. The heaviest reactions form 240Cf, 244Fm, and 248No. Low -energy fission of neighboring isotopes is mass asymmetric, correlated with proton number Z = 56. However, peak quasifission yields are at mass-symmetry for all reactions. There appears to be a very small (P-3%) systematic excess of yield correlated with Z = 56, however this is at the limit of sensitivity of the experiment.Conclusions: No significant (>3%) systematic features are seen in the quasifission mass spectra that can be unambiguously identified as resulting from shells. This small influence may result from attenuation of shell effects due to the excitation energy introduced, even in these near-barrier reactions giving low excitation energies typical of superheavy element synthesis reactions.

Quasielastic scattering and breakup angular distributions for the neutron halo nucleus Be-11 on a Pb-208 target at the laboratory energy of 210 MeV, which corresponds to 5.2 times the Coulomb barrier, were measured at HIRFL-RIBLL (Heavy-Ion Research Facility in Lanzhou and Radioactive Ion Beam Line in Lanzhou). The quasielastic scattering angular distribution of Be-11 shows an obvious suppression of the Coulomb nuclear interference peak (CNIP) even at such a high incident energy. Theoretical results with the continuum discretized coupled channels (CDCC) method are in correspondence with the experimental data. The measured angular distribution of the Be-10 fragments is well reproduced considering elastic breakup contribution with the CDCC calculations plus nonelastic breakup contribution with the model of Ichimura, Austern and Vincent [Phys. Rev. C 32,431 (1985)]. The reduced reaction cross section of the Be-11 + Pb-208 system was compared with those of other reaction systems including tightly and weakly bound projectiles impinging on medium and heavy mass targets, where the former shows a significant enhancement. Systematical comparisons between the experimental data and theoretical calculations suggest that elastic scattering with heavy targets (such as Pb-208) at relatively high incident energies is still sensitive to the structure of neutron-rich nuclei.