Abstract We study neutrino mass generation and dark matter in a left-right symmetric model. The model is based on an SU(3) c × SU(2) L × SU(2) R × U(1) B−L gauge theory with a softly broken parity symmetry. Masses of the charged leptons and neutrinos are generated radiatively at one-loop and three-loop level respectively, through their interactions with newly introduced neutral fermion and scalar particles. A mass hierarchy of those new particles is required to reproduce the observed patterns of the charged lepton spectrum and neutrino oscillation data. The resulting light particles, whose mass can be as light as GeV, serve as good dark matter candidates. The phenomenology of such dark matter candidates is governed by their interactions to left- or right-handed neutrinos. We study physics of dark matter with several benchmark parameter sets that reproduce the realistic neutrino mass matrix structure, and identify viable parameter spaces.
Nuclear and particle physics. Atomic energy. Radioactivity
Prompt Gamma Neutron Activation Analysis (PGNAA) is a nondestructive technique for elemental analysis of large-volume samples. However，the presence of neutron self-shielding effects during measurements can cause significant discrepancies between measured and true values. To address this issue，this study proposes a correction method based on an optimization algorithm to compensate for neutron self-shielding in PGNAA measurements. An experimental setup consisting of an AmBe neutron source and a high-purity germanium detector was employed to analyze boron in aqueous solutions. Standard samples were measured，and neutron self-shielding correction factors derived from MCNP simulations were used to establish a calibration curve relating boron concentration to characteristic gamma-ray counts. A neutron self-shielding correction curve for boron solutions was then computed via MCNP simulations and incorporated into a calibration model developed using the differential evolution algorithm to estimate the concentrations of unknown samples. Validation using leave-one-out cross-validation demonstrated an average relative error of 1.5%，confirming the feasibility of the proposed method for accurately determining boron concentrations in aqueous solutions of unknown composition.
Nuclear and particle physics. Atomic energy. Radioactivity
Abstract Using the D1D5 CFT we investigate transitions involving a member of a certain class of states called superstrata states, which are holographically dual to certain smooth, horizonless, 1/8-BPS, three-charge black hole microstates known as superstrata. We study these transitions by deforming the CFT away from the free orbifold point using a marginal deformation which contains a twist operator and a supercharge operator. We apply two marginal deformations to an initial state containing a graviton acting on a superstratum state. We compute amplitudes capturing transitions from this state to a graviton acting on a microstratum state, a member of a class of states which are holographically dual to certain smooth, horizonless, non-BPS, three-charge black hole microstates known as microstrata, non-BPS analogues of superstrata. We compare the resulting amplitude for various initial and final state energies to determine the preferred transition process. This may give hints as to how the dual superstratum geometry may preferentially back-react in this setting.
Nuclear and particle physics. Atomic energy. Radioactivity
Patrick Aigner, Luigi Bellafronte, Emanuele Gendy
et al.
Abstract We present a systematic study of one-loop quantum corrections in scalar effective field theories from a geometric viewpoint, emphasizing the role of field-space curvature and its renormalisation. By treating the scalar fields as coordinates on a Riemannian manifold, we exploit field redefinition invariance to maintain manifest coordinate independence of physical observables. Focusing on the non-linear sigma model (NLSM) and ϕ 4 theory, we demonstrate how loop corrections induce momentum- and scale-dependent shifts in the curvature of the field-space manifold. These corrections can be elegantly captured through the recently proposed geometry-kinematics duality, which generalizes the colour-kinematics duality in gauge theories to curved field-space backgrounds. Our results highlight a universal structure emerging in the contractions of Riemann tensors that contribute to renormalisation of the field-space curvature. In particular, we find explicit expressions and a universal structure for the running curvature and Ricci scalar in simple models, illustrating how quantum effects reshape the underlying geometry. This geometric formulation unifies a broad class of scalar EFTs, providing insight into the interplay of curvature, scattering amplitudes, and renormalization.
Nuclear and particle physics. Atomic energy. Radioactivity
Back-streaming neutrons from the spallation target of the China Spallation Neutron Source (CSNS) that emit through the incoming proton channel were exploited to build a white neutron beam facility (the so-called Back-n white neutron source), which was completed in March 2018. The Back-n neutron beam is very intense, at approximately 2 × 10 7 n/cm 2 /s at 55 m from the target, and has a nominal proton beam with a power of 100 kW in the CSNS-I phase and a kinetic energy of 1.6 GeV and a thick tungsten target in multiple slices with modest moderation from the cooling water through the slices. In addition, the excellent energy spectrum spanning from 0.5 eV to 200 MeV, and a good time resolution related to the time-of-flight measurements make it a typical white neutron source for nuclear data measurements; its overall performance is among that of the best white neutron sources in the world. Equipped with advanced spectrometers, detectors, and application utilities, the Back-n facility can serve wide applications, with a focus on neutron-induced cross-sectional measurements. This article presents an overview of the neutron beam characteristics, the experimental setups, and the ongoing applications at Back-n.
Abstract In this paper, we study the mixed system of boson stars (BSs) with wormholes at their center. The boson star is obtained by employing a complex scalar field without self-interaction or a complex scalar field with quartic self-interaction and the wormhole is obtained by employing a phantom field. Utilizing the numerical method, we successfully obtain both symmetric and asymmetric solutions within the two asymptotically flat regions. The key focus of our study involves the systematic exploration of variations in results by varying the throat parameter η 0, and the parameter c, representing the quartic term in potential. In the ground state, we find the mass M and Noether charge Q versus the scalar field frequencies ω are multi-valued curves when the η 0 is small or the self-interaction is strong, the multi-valued curves will turn into single-valued curves as η 0 or c increases. Furthermore, we observe that asymmetric solutions can transition into symmetric solutions at specific scalar field frequencies ω for certain settings of η 0 and c. In addition, when it comes to the excited state, the properties of symmetric solutions remain akin to those in the ground state, while asymmetrical results display different characteristics from the ground state. We also present the wormhole spacetime geometry to investigate the properties of this model.
Nuclear and particle physics. Atomic energy. Radioactivity
Detection of parity P\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \left(\mathcal{P}\right) $$\end{document} and time-reversal T\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \left(\mathcal{T}\right) $$\end{document} symmetry-odd electric dipole moments (EDMs) within currently achievable resolution would evidence physics beyond the Standard Model of particle physics. Via the CPT\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \left(\mathcal{CPT}\right) $$\end{document}-theorem, which includes charge conjugation C\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \left(\mathcal{C}\right) $$\end{document}, such low-energy searches complement high-energy physics experiments that probe CP\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \left(\mathcal{CP}\right) $$\end{document}-violation up to the TeV scale. Heavy-elemental atoms and molecules are considered to be among the most promising candidates for a first direct detection of P\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \mathcal{P} $$\end{document}, T\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \mathcal{T} $$\end{document}-violation due to enhancement effects that increase steeply with increasing nuclear charge number Z. However, different P\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \mathcal{P} $$\end{document}, T\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \mathcal{T} $$\end{document}-odd sources on the subatomic level can contribute to molecular or atomic EDMs, which are target of measurements, and this complicates obtaining rigorous bounds on P\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \mathcal{P} $$\end{document}, T\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \mathcal{T} $$\end{document}-violation on a fundamental level. Consequently, several experiments of complementary sensitivity to these individual P\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \mathcal{P} $$\end{document}, T\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \mathcal{T} $$\end{document}-odd sources are required for this purpose. Herein, a simply-applicable qualitative model is developed for global analysis of the P\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \mathcal{P} $$\end{document}, T\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \mathcal{T} $$\end{document}-odd parameter space from an electronic-structure theory perspective. Rules of thumb are derived for the choice of atoms and molecules in terms of their angular momenta and nuclear charge number. Contrary to naive expectations from Z-scaling laws, it is demonstrated that medium-heavy molecules with Z ≤ 54 can be of great value to tighten global bounds on P\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \mathcal{P} $$\end{document}, T\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \mathcal{T} $$\end{document}-violating parameters, in particular, if the number of complementary experiments increases. The model is confirmed by explicit density functional theory calculations of all relevant P\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \mathcal{P} $$\end{document}, T\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \mathcal{T} $$\end{document}-odd electronic structure parameters in systems that were used in past experiments or are of current interest for future experiments, respectively: the atoms Xe, Cs, Yb, Hg, Tl, Ra, Fr and the molecules CaOH, SrOH, YO, CdH, BaF, YbF, YbOH, HfF+, WC, TlF, PbO, RaF, ThO, ThF+ and PaF3+.
Evaluating the capabilities of GEANT4 code and COMSOL Multiphysics software can be achieved through coupling for an betavoltaic battery design. Spatial distribution of the deposited energy for the beta particles in the semiconductor transducer has been simulated by using the GEANT4 and then, electron-hole pair generation rate has been obtained. Subsequently, output performances of the battery such as the current-voltage (I–V) characteristics and the maximum electrical power have been determined by using the COMSOL Multiphysics in which the electron-hole pair generation rate from the GEANT4 simulation was utilized as input. Validation is done by considering an optimized planar betavoltaic battery. The results of the current study have been compared with other articles. The results are in good agreement and the relative errors are less than 8%. Our simulation model can be extended to the betavoltaic batteries with other semiconductors and radioactive isotopes, and can be provides a powerful tool for predicting the output performance and optimizing the betavoltaic batteries.
Nuclear and particle physics. Atomic energy. Radioactivity
Eric D. Brooks, MD, MHS, Fantine Giap, MD, Vincent Cassidy, MD
et al.
Purpose: Obtaining prior authorization (PA) before treatment is becoming increasingly burdensome in oncology, especially in radiation oncology. Here, we describe the impact of a strategic novel operational PA redesign to shorten authorization time and to improve patient access to cancer care at a large United States academic proton therapy center. We ask whether such a redesign may be replicable and adoptable across oncology centers.
Materials and Methods: Our PA redesign strategy was based on a 3-tiered approach. Specifically, we (1) held payors accountable to legally backed timelines, (2) leveraged expertise on insurance policies and practices, and (3) updated the submission, appeal writing, and planning procedures for PA. Metrics were compared at the following 3 time points: 6 months before, at phase-in, and at 6 months after intervention.
Results: In analyzing the impact of improving PA access to care, the percentage of approvals for commercial proton beam therapy improved by an absolute 30.6% postintervention (P < .001). The proportion of commercially insured patients treated with proton beam therapy also increased by 6.2%, and the number of new starts rose by 11.7 patients/mo. Overall patient census increased by 13 patients/d. Median authorization time was 1 week, and 90% of surveyed providers reported reduced PA burden and improved patient care.
Conclusion: This is the first validated, comprehensive operational strategy to improve access to cancer therapy while reducing the burden of PA. This novel approach may be helpful for addressing barriers to PA in medical and surgical oncology because the redesign is predicated on laws that regulate PA across disciplines.
Medical physics. Medical radiology. Nuclear medicine, Nuclear and particle physics. Atomic energy. Radioactivity
In this work we derive a systematic short-range expansion of the many-body wave function. At leading order, the wave function is factorized to a zero-energy $s$-wave correlated pair and spectator particles, while terms that include energy derivatives and larger orbital angular momentum two-body functions appear at subleading orders. The validity of the expansion is tested for the two-body case, as well as the many-body case, where infinite neutron matter is considered. An accurate and consistent description of both coordinate-space two-body densities and the one-body momentum distribution is obtained. These results show the possibility to utilize such an expansion for describing different observables in strongly-interacting many-body systems, including nuclear, atomic and condensed-matter systems. This work also enables a systematic description of large momentum transfer reactions in nuclear systems sensitive to short-range correlations, provides a link between such experiments and low-energy nuclear physics, and motivates measurement of new observables in these experiments.
Abstract We study the brane/flux annihilation in the double-throat system in which the corresponding cycles of two throats are homologically equivalent. When we put D 3 ¯ $$ \overline{\mathrm{D}3} $$ -branes at only one of throat tips, two throats are no longer identical. Then the brane/flux annihilation can be interpreted as the process for reducing the difference between two throat geometries through the transition to the supersymmetric vacuum. To see this, we describe the changes in the amounts of the NSNS 3-form flux supporting the B-cycle contained in two throat regions during the brane/flux annihilation. We also compare our analysis with the recently proposed thraxion scenario, which also describes the inequivalence of two throats caused by the different NSNS 3-form flux distributions in two throat regions.
Nuclear and particle physics. Atomic energy. Radioactivity
We analyze the critical behavior of isotropic systems with dipole-dipole interaction by renormalization-group methods in fixed space-time dimensions. Working in three-dimensional theory we analytically find three-loop expressions for critical exponents in the limit of dominating dipole-dipole forces. Resummation of the series obtained provides numerical values close to O(3)-theory predictions, justifying the applicability of such a simplified model to systems with strong dipole-dipole interaction.
Nuclear and particle physics. Atomic energy. Radioactivity
Go Ichikawa,0,1,∗ Yasuhiro Fuwa, Takuro Hasegawa, Masahiro Hino, Katsuya Hirota, Takashi Ino, Yoshihisa Iwashita, Masaaki Kitaguchi, 5 Jun Koga, Shun Matsuzaki, Kenji Mishima, Takanori Mogi, Koki Morikawa, Hiroki Okabe, Hidetoshi Otono, Yoshichika Seki, 9 Daiichiro Sekiba, Tatsushi Shima, Haruki Shimizu, Hirohiko Shimizu, Naoyuki Sumi, Hirochika Sumino, Satoru Yamashita, Kodai Yano and Tamaki Yoshioka High Energy Accelerator Research Organization (KEK), Tsukuba, 305-0801, Japan J-PARC Center, Tokai, 319-1195, Japan Japan Atomic Energy Agency, Tokai, 319-1195, Japan Department of Physics, Nagoya University, Nagoya, 464-8602, Japan Institute for Integrated Radiation and Nuclear Science, Kyoto University, Kumatori, 594-0494, Japan 5 Kobayashi-Maskawa Institute for the Origin of Particles and the Universe (KMI), Nagoya Unversity, Nagoya, 464-8602, Japan Department of Physics, Graduate School of Science, Kyushu University, Fukuoka, 819-0395, Japan Department of Physics, The University of Tokyo, Tokyo 113-0033, Japan Research Center for Advanced Particle Physics (RCAPP), Kyushu University, Fukuoka, 819-0395, Japan Center for Physics and Mathematis, Osaka Electro-Communication University, Neyagawa, 572-8530, Japan : Institute of Applied Physics, University of Tsukuba, Tsukuba, 305-8573, Japan Research Center for Nuclear Physics (RCNP), Osaka University, Ibaraki, 567-0047, Japan The Graduate University for Advanced Studies, Hayama, 240-0193, Japan Department of General Systems Studies, Graduate School of Arts and Science, The University of Tokyo, Tokyo, 153-8902, Japan International Center for the Elementary Particle Physics (ICEPP), The University of Tokyo, Tokyo, 113-0033, Japan E-mail: go.ichikawa@kek.jp
The study of nuclear reactions between elementary particles and atomic nuclei plays an important role in understanding the interdisciplinary area of Nuclear Physics and Particle Physics. The study of photoproduction of mesons has a long history going back to 1950′s. It was in the next decade, studies on photoproduction of π meson on deuteron started. Since then coherent and incoherent photoproduction of π meson on deuteron have been studied theoretically and experimentally. The study of photoproduction of pions describes the coupling among photon, meson and nucleon fields and also gives information about strong interactions that indirectly hold the nucleus together. A thorough investigation of the photoproduction process is firmly believed to give first hand information on two important aspects, one being the threshold of π photoproduction amplitude and the other being propagation of low-energy pions in nuclear medium. The purpose of the present contribution is to theoretically study pion photoproduction on deuterons using model independent irreducible tensor formalism developed earlier to study the photodisintegration of deuterons[1].
L. Xie, P. Cao,a,b,1,∗ T. Yu, X. Tang, Z. Jiang, Q. An, Xi. Huang, C. Li, J. Li, M. Gu, Q. Zhang, G. Luan, X. Ruan, G. He, J. Ren, J. Bai, f J. Bao, Y. Bao, H. Chen, Q. Chen, f Y. Chen, Z. Chen, Z. Cui, R. Fan, C. Feng, K. Gao, X. Gao, C. Han, Z. Han, f Y. He, Y. Hong, j Y. Hu, H. Huang, H. Jiang, W. Jiang, H. Jing, L. Kang, B. Li, Q. Li, X. Li, Y. Li, J. Liu, R. Liu, f S. Liu, X. Liu, f Z. Long, C. Ning, M. Niu, B. Qi, Z. Ren, f Z. Song, K. Sun, j Z. Sun, Z. Tan, J. Tang, j B. Tian, L. Wang, j P. Wang, Z. Wang, Z. Wen, f X. Wu, X. Wu, X. Yang, Y. Yang, f H. Yi, L. Yu, Y. Yu, G. Zhang, L. Zhang, j X. Zhang, Y. Zhang, Z. Zhang, L. Zhou, j Z. Zhou j and K. Zhu j State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei, China Department of Modern Physics, University of Science and Technology of China, Hefei, China Institute of High Energy Physics, Chinese Academy of Sciences (CAS), Beijing, China State Key Laboratory of Particle Detection and Electronics, Institute of High Energy Physics Chinese Academy of Sciences, Beijing, China Key Laboratory of Nuclear Data, China Institute of Atomic Energy, Beijing, China f Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, China Spallation Neutron Source Science Center, Dongguan, China State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing, China Northwest Institute of Nuclear Technology, Xi’an, China University of Chinese Academy of Sciences, Beijing, China