ITP OpenIR中国科学院理论物理研究所http://ir.itp.ac.cn/:802024-03-19T11:09:59Z2024-03-19T11:09:59ZNovel loop-diagrammatic approach to QCD θ parameter and application to the left-right modelHisano, JunjiKitahara, TeppeiOsamura, NaohiroYamada, Atsuyukihttp://ir.itp.ac.cn/:80/handle/311006/281142024-03-19T02:48:53Z2024-03-19T02:48:53Z题名: Novel loop-diagrammatic approach to QCD θ parameter and application to the left-right model
作者: Hisano, Junji; Kitahara, Teppei; Osamura, Naohiro; Yamada, Atsuyuki
摘要: When the QCD axion is absent in full theory, the strong CP problem has to be explained by an additional mechanism, e.g., the left-right symmetry. Even though treelevel QCD theta($) over bar parameter is restricted by the mechanism, radiative corrections to theta($) over bar are mostly generated, which leads to a dangerous neutron electric dipole moment (EDM). The ordinary method for calculating the radiative theta($) over bar utilizes an equation theta($) over bar = -arg detmloop q based on the chiral rotations of complex quark masses. In this paper, we point out that when full theory includes extra heavy quarks, the ordinary method is unsettled for the extra quark contributions and does not contain its full radiative corrections. We formulate a novel method to calculate the radiative corrections to theta($) over bar through a direct loop-diagrammatic approach, which should be more robust than the ordinary one. As an application, we investigate the radiative theta($) over bar in the minimal left-right symmetric model. We first confirm a seminal result that two-loop level radiative theta($) over bar completely vanishes (corresponding to oneloop corrections to the quark mass matrices). Furthermore, we estimate the size of a nonvanishing radiative theta($) over bar at three-loop level. It is found that the resultant induced neutron EDM is comparable to the current experimental bound, and the expected size is restricted by the perturbative unitarity bound in the minimal left-right model.2024-03-19T02:48:53ZΞc - Ξ′c mixing from lattice QCDLiu, HangLiu, LiumingSun, PengSun, WeiTan, Jin-XinWang, WeiYang, Yi-BoZhang, Qi-Anhttp://ir.itp.ac.cn/:80/handle/311006/281132024-03-19T03:39:54Z2023-12-07T03:01:03Z题名: Ξc - Ξ′c mixing from lattice QCD
作者: Liu, Hang; Liu, Liuming; Sun, Peng; Sun, Wei; Tan, Jin-Xin; Wang, Wei; Yang, Yi-Bo; Zhang, Qi-An
摘要: In heavy quark limit, the lowest-lying charmed baryons with two light quarks can form an SU(3) triplet and sextet. The Xi(c) in the SU(3) triplet and Xi'(c) in the sextet have the same J(PC) quantum number and can mix due to the finite charm quark mass and the fact the strange quark is heavier than the up/down quark. We explore the Xi(c)-Xi'(c) mixing by calculating the two-point correlation functions of the Xi(c) and Xi'(c) baryons from lattice QCD. Based on the lattice data, we adopt two independent methods to determine the mixing angle between Xi(c) and Xi'(c). After making the chiral and continuum extrapolation, it is found that the mixing angle theta is 1.2 degrees +/- 0.1 degrees, which seems insufficient to account for the large SU(3) symmetry breaking effects found in weak decays of charmed baryons. (c) 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).2023-12-07T03:01:03ZΛc(2910) and Λc(2940) as conventional baryons dressed with the D*N channelZhang, Zi-LeLiu, Zhan-WeiLuo, Si-QiangWang, Fu-LaiWang, BoXu, Haohttp://ir.itp.ac.cn/:80/handle/311006/281122024-03-19T03:39:53Z2023-12-07T03:01:02Z题名: Λc(2910) and Λc(2940) as conventional baryons dressed with the D*N channel
作者: Zhang, Zi-Le; Liu, Zhan-Wei; Luo, Si-Qiang; Wang, Fu-Lai; Wang, Bo; Xu, Hao
摘要: In this work, we treat Ac(2910)+ and Ac(2940)+ as the conventional udc cores dressed with the D*N channel. We provide a possible interpretation to both Ac(2910)+ and Ac(2940)+ within the same framework. In the study, we consider not only the effects between the conventional triquark core and the D*N channel but also the D*N-D*N interactions. The mass of the Ac state with JP = 1=2- is larger than that with JP = 3=2- in this unquenched picture, which is very different from the prediction of the conventional quenched quark model. Based on the mass spectrum, the spin parity of Ac(2940)+ is more likely to be 1=2-, while Ac(2910)+ prefers 3=2-. We look forward to the future experiments that can test our results with more precise experimental data.2023-12-07T03:01:02ZWhat can we learn from the total width of the Higgs boson?*Cao, Qing-HongLi, Hao-LinXu, Ling-XiaoYu, Jiang-Haohttp://ir.itp.ac.cn/:80/handle/311006/281112024-03-19T03:39:51Z2023-12-07T03:01:00Z题名: What can we learn from the total width of the Higgs boson?*
作者: Cao, Qing-Hong; Li, Hao-Lin; Xu, Ling-Xiao; Yu, Jiang-Hao
摘要: As one of the key properties of the Higgs boson, the Higgs total width is sensitive to the global profile of the Higgs boson couplings, and thus new physics would modify the Higgs width. We investigate the total width in various new physics models, including various scalar extensions, composite Higgs models, and the fraternal twin Higgs model. Typically, the Higgs width is smaller than the standard model value due to mixture with other scalars if the Higgs is elementary, or curved Higgs field space for the composite Higgs. On the other hand, except for the possible invisible decay mode, the enhanced Yukawa coupling in the two Higgs doublet model or the exotic fermion embeddings in the composite Higgs could enhance the Higgs width greatly. The precision measurement of the Higgs total width at the high-luminosity LHC can be used to discriminate certain new physics models.2023-12-07T03:01:00ZWeyl Phonons in Chiral CrystalsZhang, TiantianHuang, ZhihengPan, ZitianDu, LuojunZhang, GuangyuMurakami, Shuichihttp://ir.itp.ac.cn/:80/handle/311006/281102024-03-19T03:39:49Z2023-12-07T03:00:59Z题名: Weyl Phonons in Chiral Crystals
作者: Zhang, Tiantian; Huang, Zhiheng; Pan, Zitian; Du, Luojun; Zhang, Guangyu; Murakami, Shuichi
摘要: Chirality is an indispensable conceptthat pervades fundamentalscience and nature, manifesting itself in diverse forms, e.g., quasiparticles, and crystal structures. Ofparticular interest are Weyl phonons carrying specific Chern numbersand chiral phonons doing circular motions. Up to now, they have beenstudied independently and the interpretations of chirality seem tobe different in these two concepts, impeding our understanding. Here,we demonstrate that they are entangled in chiral crystals. Employinga typical chiral crystal of elementary tellurium (Te) as a case study,we expound on the intrinsic relationship between Chern number of Weylphonons and pseudoangular momentum (PAM, l ( ph )) of chiral phonons. We propose Raman scatteringas a new technique to demonstrate the existence of Weyl phonons inTe, by detecting the chirality-induced energy splitting between thetwo constituent chiral phonon branches for Weyl phonons. Moreover,we also observe the obstructed phonon surface states for the firsttime.2023-12-07T03:00:59ZW-boson mass anomaly from a general SU(2) L scalar multipletWu, JiajunHuang, DaGeng, Chao-Qianghttp://ir.itp.ac.cn/:80/handle/311006/281092024-03-19T03:39:47Z2023-12-07T03:00:57Z题名: W-boson mass anomaly from a general SU(2) L scalar multiplet
作者: Wu, Jiajun; Huang, Da; Geng, Chao-Qiang
摘要: We explain the W-boson mass anomaly by introducing an W-boson mass arises at the one-loop level, which can be expressed in terms of the electroweak (EW) oblique parameters T and S at leading order. We first rederive the general formulae of T and S induced by a scalar multiplet of EW charges, confirming the results in literature. We then study several specific examples of great phenomenological interest by applying these general expressions. As a result, it is found that the model with a scalar multiplet in an T and S. However, the cases with scalars in a complex representation under T and S. We further consider the strong constraints from the perturbativity and EW global fit of the precision data and vary the isospin representation and hypercharge of the additional scalar multiplet to assess the extent of the model to solve the W-boson mass anomaly. It turns out that these constraints play important roles in setting limits on the model parameter space. We also briefly describe the collider signatures of the extra scalar multiplet, especially when it contains long-lived, heavy, highly charged states.2023-12-07T03:00:57ZVisualizing slow internal relaxations in a two-dimensional glassy systemChen, YanshuangYe, ZefangWang, KexinHuang, JipingTong, HuaJin, YuliangChen, KeTanaka, HajimeTan, Penghttp://ir.itp.ac.cn/:80/handle/311006/281082024-03-19T06:23:47Z2023-12-07T03:00:56Z题名: Visualizing slow internal relaxations in a two-dimensional glassy system
作者: Chen, Yanshuang; Ye, Zefang; Wang, Kexin; Huang, Jiping; Tong, Hua; Jin, Yuliang; Chen, Ke; Tanaka, Hajime; Tan, Peng
摘要: Glasses relax internally even when their structure is frozen. Observations of a two-dimensional glass former now show that although structure relaxation freezes with the glass transition, non-constrained bonds survive; this accounts for persisting internal relaxation. Unlike a crystal, a glassy solid state displays slow internal relaxation processes besides vibrational modes even when structural (alpha) relaxation is frozen. The precise nature of such residual local relaxation modes remains poorly understood due to the lack of real-space information. Here we directly visualize the internal relaxations in a glass via a long-time observation of the dynamics of a mechanically driven two-dimensional granular system that shows a pinning-induced transition. This allows directly visualizing the internal relaxations in a glass. On approaching the glass transition, vanishing cage-breaking motion is observed, accompanied by the emergence of a restricted dynamic mode characterizing slow beta relaxation. The emergence of bond rigidity freezes the structure relaxation and leads to slow beta motion. Our findings indicate that unlike crystallization, where all the bonds are constrained, vitrification in a disordered system freezes alpha relaxation and accompanies elastic percolation, but the remaining non-constrained bonds provide room for slow beta relaxation.2023-12-07T03:00:56ZVariational theory of angulons and their rotational spectroscopyZeng, ZhongdaYakaboylu, EnderalpLemeshko, MikhailShi, TaoSchmidt, Richardhttp://ir.itp.ac.cn/:80/handle/311006/281072024-03-19T02:52:04Z2023-12-07T03:00:55Z题名: Variational theory of angulons and their rotational spectroscopy
作者: Zeng, Zhongda; Yakaboylu, Enderalp; Lemeshko, Mikhail; Shi, Tao; Schmidt, Richard
摘要: The angulon, a quasiparticle formed by a quantum rotor dressed by the excitations of a many-body bath, can be used to describe an impurity rotating in a fluid or solid environment. Here, we propose a coherent state ansatz in the co-rotating frame, which provides a comprehensive theoretical description of angulons. We reveal the quasiparticle properties, such as energies, quasiparticle weights, and spectral functions, and show that our ansatz yields a persistent decrease in the impurity's rotational constant due to many-body dressing, which is consistent with experimental observations. From our study, a picture of the angulon emerges as an effective spin interacting with a magnetic field that is self-consistently generated by the molecule's rotation. Moreover, we discuss rotational spectroscopy, which focuses on the response of rotating molecules to a laser perturbation in the linear response regime. Importantly, we take into account initial-state interactions that have been neglected in prior studies and reveal their impact on the excitation spectrum. To examine the angulon instability regime, we use a singleexcitation ansatz and obtain results consistent with experiments, in which a broadening of spectral lines is observed while phonon wings remain highly suppressed due to initial-state interactions. (c) 2023 Author(s).2023-12-07T03:00:55ZUpper limits on the polarized isotropic stochastic gravitational-wave background from advanced LIGO-Virgo's first three observing runsJiang, YangHuang, Qing-Guohttp://ir.itp.ac.cn/:80/handle/311006/281062024-03-19T02:52:01Z2023-12-07T03:00:53Z题名: Upper limits on the polarized isotropic stochastic gravitational-wave background from advanced LIGO-Virgo's first three observing runs
作者: Jiang, Yang; Huang, Qing-Guo
摘要: Parity violation is expected to generate an asymmetry between the amplitude of left and right-handed gravitational-wave modes which leads to a circularly polarized stochastic gravitational-wave background (SGWB). Due to the three independent baselines in the LIGO-Virgo network, we focus on the amplitude difference in strain power characterized by Stokes' parameters and do maximum-likelihood estimation to constrain the polarization degree of SGWB. Our results indicate that there is no evidence for the circularly polarized SGWB in the data. Furthermore, by modeling the SGWB as a power-law spectrum, we place upper limit on the normalized energy density Qgw(25 Hz) < 5.3 x 10-9 at 95% confidence level after marginalizing over the polarization degree and spectral index.2023-12-07T03:00:53ZUpdated and novel limits on double beta decay and dark matter-induced processes in platinumBroerman, B.Laubenstein, M.Nagorny, S. S.Nisi, S.Song, N.Vincent, A. C.http://ir.itp.ac.cn/:80/handle/311006/281052024-03-19T02:51:59Z2023-12-07T03:00:52Z题名: Updated and novel limits on double beta decay and dark matter-induced processes in platinum
作者: Broerman, B.; Laubenstein, M.; Nagorny, S. S.; Nisi, S.; Song, N.; Vincent, A. C.
摘要: A 510 day long-term measurement of a 45.3 g platinum foil acting as the sample and high voltage contact in an ultra-low-background high purity germanium detector was performed at Laboratori Nazionali del Gran Sasso (Italy). The data was used for a detailed study of double beta decay modes in natural platinum isotopes. Limits are set in the range O(10(14)-10(19)) years (90% C.L.) for several double beta decay transitions to excited states confirming, and par-tially extending existing limits. The highest sensitivity of the measurement, greater than 10(19) years, was achieved for the two neutrino and neutrinoless double beta decay modes of the isotope Pt-198. Additionally, novel limits for inelastic dark matter scattering on Pt-195 are placed up to mass splittings of approximately 500 keV. We analyze several techniques to extend the sensitivity and propose a few approaches for future medium-scale experiments with platinum-group elements.2023-12-07T03:00:52Z