Tue·Nov 23, 2021Tuesday·November 23, 2021

1. 01*

   A template method to measure the $t\bar{t}$ polarisation

   J. A. Aguilar-Saavedra🇪🇸 · M.C.N. Fiolhais🇺🇸 · P. Martín-Ramiro🇪🇸 · J. M. Moreno🇪🇸 · A. Onofre🇵🇹

   We develop a template method for the measurement of the polarisation of $t\bar{t}$ pairs produced in hadron collisions. The method would allow to extract the individual fractions of $t_L{\bar{t}}_L$, $t_R{\bar{t}}_R$, $t_L{\bar{t}}_R$ and $t_R{\bar{t}}_L$ pairs with a fit to data, where $L,R$ refer to the polarisation along any axis. These polarisation fractions have not been independently measured at present. Secondarily, the method also provides the net polarisation of $t$ and $\bar{t}$, as well as their spin correlation for arbitrary axes.

   hep-phEPJC(2022)·10 citations
2. 02*

   Neutrino spin operator and dispersion in moving matter

   A.Grigoriev · A.Studenikin🇷🇺 · A.Ternov

   We found a spin integral of motion for neutrino, which propagates in moving and polarized matter. The operator obtained opens up the possibility of consistent classification of neutrino states in such a medium and, as a consequence, a systematic description of the related physical phenomena. Using the operator, we obtain a dispersion relation for neutrinos and consider its particular cases.

   hep-phEPJC(2022)·3 citations
3. 03*

   Likelihood analysis of the flavour anomalies and $g-2$ in the general two Higgs doublet model

   Peter Athron🇨🇳 · Csaba Balazs🇦🇺 · Tomás E. Gonzalo🇩🇪 · Douglas Jacob🇦🇺 · Farvah Mahmoudi🇫🇷 · Cristian Sierra🇨🇳

   We present a likelihood analysis of the general two Higgs doublet model, using the most important currently measured flavour observables, in view of the anomalies in charged current tree-level and neutral current one-loop rare decays of $B$ mesons in $b\to cl\overline{\nu }$ and $b\to s{\mu }^{+}{\mu }^{-}$ transitions, respectively. We corroborate that the model explains the latter and it is able to simultaneously fit the experimental values of the $R(D)$ ratio at $1\sigma$, but it can not accommodate the $R(D^{\ast })$ and $F_L(D^{\ast })$ observables. We find that the fitted values for the angular observables in $b\to s{\mu }^{+}{\mu }^{-}$ transitions exhibit better agreement with the general two Higgs double model in comparison to the SM. We also make predictions for future collider observables $\mathrm{BR}(t\to ch)$, $\mathrm{BR}(h\to bs)$, $\mathrm{BR}(h\to \tau \mu )$, $\mathrm{BR}(B_s\to {\tau }^{+}{\tau }^{-})$, $\mathrm{BR}(B^{+}\to K^{+}{\tau }^{+}{\tau }^{-})$ and the flavour violating decays of the $\tau$ lepton, $\mathrm{BR}(\tau \to 3\mu )$ and $\mathrm{BR}(\tau \to \mu \gamma )$. The model predicts values of $\mathrm{BR}(t\to ch)$, $\mathrm{BR}(B_s\to {\tau }^{+}{\tau }^{-})$ and $\mathrm{BR}(B^{+}\to K^{+}{\tau }^{+}{\tau }^{-})$ that are out of reach of future experiments, but its predictions for $\mathrm{BR}(h\to bs)$ and $\mathrm{BR}(h\to \tau \mu )$ are within the future sensitivity of the HL-LHC or the ILC. We also find that the predictions for the $\tau \to 3\mu$ and $\tau \to \mu \gamma$ decays are well within the projected limits of the Belle II experiment. Finally, using the latest measurement of the Fermilab Muon $g-2$ Collaboration, we performed a simultaneous fit to $\Delta a_{\mu }$ constrained by the charged anomalies, finding solutions at the $1\sigma$ level. Once the neutral anomalies are included, however, a simultaneous explanation is unfeasible.

   hep-phJHEP(2022)·36 citations
4. 04*

   Using a nested anomaly detection machine learning algorithm to study the neutral triple gauge couplings at an $e^{+}{e}^{-}$ collider

   Ji-Chong Yang🇨🇳 · Yu-Chen Guo🇨🇳 · Li-Hua Cai🇨🇳

   Anomaly detection algorithms have been proved to be useful in the search of new physics beyond the Standard Model. However, a prerequisite for using an anomaly detection algorithm is that the signal to be sought is indeed anomalous. This does not always hold true, for example when interference between new physics and the Standard Model becomes important. In this case, the search of new physics is no longer an anomaly detection. To overcome this difficulty, we propose a nested anomaly detection algorithm, which appears to be useful in the study of neutral triple gauge couplings at the CEPC, the ILC and the FCC-ee. Our approach inherits the advantages of the anomaly detection algorithm been nested, while at the same time, it is no longer an anomaly detection algorithm. As a complement to anomaly detection algorithms, it can achieve better results on problems that are no longer anomaly detection.

   hep-phNPB(2022)·21 citations
5. 05*

   The pseudoscalar meson and baryon octet interaction with strangeness $S=-2$ in the unitary coupled-channel approximation

   Bao-Xi Sun🇨🇳 · Xin-Yu Liu🇨🇳

   The interaction of the pseudoscalar meson and the baryon octet is investigated by solving the Bethe-Salpeter equation in the infinite and finite volume respectively. It is found that there is a resonance state generated dynamically, which owns a mass about 1550MeV and a large decay width of 120-200MeV. This resonance state couples strongly to the $\pi \Xi$ channel. Therefore, it might not correspond to the $\Xi (1620)$ particle announced by Belle collaboration. At the same time, this problem is studied in the finite volume, and an energy level at 1570MeV is obtained, which is between the $\pi \Xi$ and $\bar{K}\Lambda$ thresholds and independent of the cubic box size.

   hep-phCommun.Theor.Phys.(2022)·1 citation
6. 06*

   Non-perturbative bounds for $B\to D^{(\ast )}\ell {\nu }_{\ell }$ decays and phenomenological applications

   Guido Martinelli🇮🇹 · Silvano Simula🇮🇹 · Ludovico Vittorio🇮🇹

   We show how to extract the Cabibbo-Kobayashi-Maskawa (CKM) matrix element $|V_{cb}|$ from exclusive semileptonic $B\to D^{(\ast )}$ decays by using the Dispersive Matrix (DM) method. It is a new approach which allows to determine in a full non-perturbative way the hadronic form factors (FFs) in the whole kinematical range, without making any assumption on their dependence on the momentum transfer. We investigate also the issue of Lepton Flavor Universality (LFU) by computing a pure theoretical estimate of the ratio $R(D^{(\ast )})$. Our approach is applied to the preliminary LQCD computations of the FFs, published by the FNAL/MILC [1] and the JLQCD [2] Collaborations, for the $B\to D^{\ast }$ decays and to the final ones, computed by FNAL/MILC [3], for the $B\to D$ transitions . Since the FNAL/MILC Collaborations have recently published the final results of their LQCD computations of the FFs [4] for the $B\to D^{\ast }$ case, we present also the results of our procedure after its application on these data. We find $|V_{cb}|=(41.0\pm 1.2)\cdot 10^{-3}$ and $|V_{cb}|=(41.3\pm 1.7)\cdot 10^{-3}$ from $B\to D$ and $B\to D^{\ast }$ decays, respectively. These estimates are consistent within $1\sigma$ with the most recent inclusive determination $|V_{cb}{|}_{incl}=(42.16\pm 0.50)\cdot 10^{-3}$ [5]. Furthermore, we obtain $R(D)=0.289(8)$ and $R(D^{\ast })=0.269(8)$, which are both compatible with the latest experimental averages [6] at the $\sim$1.6$\sigma$ level.

   hep-phhep-exhep-latPoS(2022)·6 citations
7. 07*

   FIMP dark matter mediated by massive gauge boson around the phase transition period and the gravitational waves production

   Ligong Bian🇨🇳 · Yi-Lei Tang🇨🇳 · Ruiyu Zhou🇨🇳

   We study the feebly interacting massive particle dark matter whose production processes are significantly affected by the phase evolution and the complicated thermal corrections to the vector boson. We calculate the freeze-in processes to obtain the correct dark matter relic density by enumerating all the possible $1\leftrightarrow 2$ and $2\leftrightarrow 2$ processes. The predicted gravitational waves emitted by the first-order phase transitions and the cosmic strings are evaluated.

   hep-phPRD(2022)·13 citations
8. 08*

   Scattering amplitudes in the Regge limit and the soft anomalous dimension through four loops

   Giulio Falcioni🇬🇧 · Einan Gardi🇬🇧 · Niamh Maher🇬🇧 · Calum Milloy🇮🇹 · Leonardo Vernazza🇮🇹

   Using rapidity evolution equations we study two-to-two gauge-theory scattering amplitudes in the Regge limit. We carry out explicit computations at next-to-next-to-leading logarithmic accuracy through four loops and present new results for both infrared-singular and finite contributions to the amplitude. New techniques are devised in order to derive the colour structure stemming from three-Reggeon exchange diagrams in terms of commutators of channel operators, obtaining results that are valid for any gauge group, and apply to scattered particles in any colour representation. We also elucidate the separation between contributions to the Regge cut and Regge pole in the real part of the amplitude to all loop orders. We show that planar contributions due to multiple-Reggeon exchange diagrams can be factorised as a Regge pole along with the single-Reggeon exchange, and when this is done, the singular part of the gluon Regge trajectory is directly determined by the cusp anomalous dimension. We explicitly compute the Regge cut component of the amplitude through four loops and show that it is non-planar. From a different perspective, the new results provide important information on soft singularities in general kinematics beyond the planar limit: by comparing the computed corrections to the general form of the four-loop soft anomalous dimension we derive powerful constraints on its kinematic dependence, opening the way for a bootstrap-based determination.

   hep-phhep-thJHEP(2022)·49 citations
9. 09*

   QCD resummation for high-p${}_T$ jet shapes at hadron colliders

   Kamel Khelifa-Kerfa🇬🇧

   Exploiting the substructure of jets observed at the LHC to better understand and interpret the experimental data has recently been a very active area of research. In this thesis we study the substructure of high-p${}_T$ QCD jets, which form a background to many new physics searches. In particular, we explore in detail the perturbative distributions of a certain class of observables known as non-global jet shapes. More specifically, we identify and present state-of-the-art calculations, both at fixed-order and to all-orders in the perturbative expansion, of a set of large logarithms known as non-global logarithms. Hitherto, these logarithms have been largely mistreated, and in many cases ignored, in the literature despite being first pointed out more than a decade ago. Our work has triggered the interest of many groups, particularly Soft and Collinear Effective Theory (SCET) groups, and led to a flurry of papers on non-global logarithms and related issues.

   hep-ph7 citations
10. 10*

    The Higgs condensate as a quantum liquid: Comparison with the ATLAS full Run 2 data

    Paolo Cea🇮🇹

    Recently, we proposed to picture the Higgs condensate of the Standard Model as a quantum liquid analogous to the superfluid Helium II. In this scenario the Higgs condensate excitations resemble closely two Standard Model Higgs bosons. The lightest Higgs boson was already identified with the LHC narrow resonance at 125 GeV. Concerning the heavy Higgs boson, we found preliminary evidence in our previous phenomenological analysis in the so-called golden channel. In the present note we compared our proposal to the full Run 2 data set released recently by the ATLAS Collaboration. Even though we do not found a clear statistical evidence for our Standard Model heavy Higgs, we found that our theoretical proposal is still in accordance with the available observations.

    hep-phhep-ex2 citations
11. 11*

    Atomic Size Dark Matter Pearls, Electron Signal

    C. D. Froggatt (Glasgow University)🇬🇧 · H.B.Nielsen (Niels Bohr Institute)🇩🇰

    We explain both the observation of dark matter by the seasonal variation of the DAMA-LIBRA data and the observation of ``electron recoil'' events at Xenon1T by the SAME dark matter model. This DM is bubbles of a new type of vacuum containing ordinary atomic matter under high pressure ensured by the surface tension of the domain wall. Surrounding it a cloud of electrons almost of atomic size. Also we explain the self interactions of dark matter suggested by astronomical studies of dwarf galaxies etc. Interaction in the shielding slows the dark matter down to a low terminal velocity. Nuclei in the underground detectors are thus not detected. Further we explain the ``mysterious'' X-ray line of 3.5 keV from our dark matter particles colliding with each other so that the surfaces/skins unite. Even the 3.5 keV X-ray radiation from the Tycho supernova remnant is explained as our pearls hitting cosmic rays in the remnant. DAMA-LIBRA and Xenon1T experiments see supposedly our dark matter pearls excited during their stopping in the shielding or the air. The most remarkable support for our type of model is that both these underground experiments see events with about 3.5 keV energy, just the energy of the X-ray line. We get a good numerical understanding of the fitted cross section over mass ratio of self interacting dark matter observed in the study of dwarf galaxies. Also the total energy of the dark matter pearls stopped in the shield is reasonably matching order of magnitudewise with the absolute observation rates of DAMA-LIBRA and Xenon1T, although the their ratio requires further development. Accepting that the different phases of the vacuum could be realized inside the Standard Model, our whole scheme also could. No new physics is needed for dark matter!

    hep-ph8 citations
12. 12*

    Validity of the Semiclassical Approximation in 1+1 Electrodynamics: Numerical Solutions to the Linear Response Equation

    Ian M. Newsome🇺🇸

    From previous work arXiv:2010.09811, the semiclassical backreaction equation in 1+1 dimensions was solved and a criterion was implemented to assess the validity of the semiclassical approximation in this case. The criterion involves the behavior of solutions to the linear response equation which describes perturbations about solutions to the semiclassical backreaction equation. The linear response equation involves a time integral over a two-point correlation function for the current induced by the quantum field and it is expected that significant growth in this two-point function (and therefore in quantum fluctuations) will result in significant growth in solutions to the linear response equation. It was conjectured for early times that the difference of two nearby solutions to the semiclassical backreaction equation, with similar initial conditions, can act as an approximate solution to the linear response equation. A comparative analysis between the approximate and numerical solutions to the linear response equation, for the critical scale for particle production, will be presented for the case of a massive, quantized spin 1/2 field in order to determine how robust the approximation method is for representing its solutions.

    hep-phgr-qchep-th1 citation
13. 13*

    A Bottom-Up Approach: The Data Driven Flavour Model

    L. Merlo🇪🇸

    A bottom-up approach has been adopted to identify a flavour model that agrees with present experimental measurements. The charged fermion mass hierarchies suggest that only the top Yukawa term should be present at the renormalisable level. The flavour symmetry of the Lagrangian including the fermionic kinetic terms and only the top Yukawa is then a combination of $U(2)$ and $U(3)$ factors. Lighter charged fermion and active neutrino masses and quark and lepton mixings arise considering specific spurion fields. The associated phenomenology is investigated and the model turns out to have almost the same flavour protection of the Minimal Flavour Violation, in both quark and lepton sectors. Promoting the spurions to be dynamical fields, the associated scalar potential is also studied and a minimum is identified such that fermion masses and mixings are correctly reproduced.

    hep-phMoscow Univ.Phys.Bull.(2022)·0 citations
14. 14*

    Low Energy Effective Theory for Axion Strings

    Michael Dine🇺🇸

    We consider aspects of the low energy description of global cosmic strings. In the non-relativistic limit, we study the extent to which these are described by the combination of the Nambu-Gotto and Kalb-Ramond actions. While in a formal sense this is the case for infiniately long strings, for more realistic situations, the collective coordinates of the system do not provide a complete description for more than brief intervals; as time evolves it becomes necessary to include low momentum goldstone excitations as well.

    hep-phhep-thJCAP(2022)·0 citations
15. 15*

    Zee model in a modular $A_4$ symmetry

    Takaaki Nomura🇨🇳 · Hiroshi Okada🇰🇷 · Yong-hui Qi🇰🇷

    We study a Zee model applying a modular $A_4$ symmetry in supersymmetry framework, where we construct our lepton model as minimum modular weight as possible. We show our predictions on phases and neutrino masses through numerical analysis. We find a model that can fit in both normal and inverted hierarchy cases of neutrino mass. The predictions of neutrino observables are shown where we obtain more constrained allowed region in the inverted hierarchy case.

    hep-phEPJC(2025)·20 citations
16. 16*

    Positronium Decays with Dark $Z$ and Fermionic Dark Matter

    Dong-Won Jung🇰🇷 · Chaehyun Yu🇰🇷 · Kang Young Lee🇰🇷

    We investigate the invisible decay of positronium to probe the fermionic light dark matter mediated by the dark $Z$ boson. Too tiny is the invisible decay rate of positronium through weak interaction in the standard model to be detected in the experiment. We show that it can be enhanced to be observed in the future if the dark matter is lighter than the electron in the dark $Z$ model. We also compute the relic abundance of such light dark matter and discuss the Big Bang Nucleosynthesis constraint with an alternative thermal history scenario.

    hep-phPRD(2022)·6 citations
17. 17*

    Detection Prospects of Dark Matter in Einstein Telescope

    Chuan-Ren Chen🇹🇼 · Chrisna Setyo Nugroho🇹🇼

    We improve the calculations of the elastic motion induced by the dark matter hits on the surface of the mirror equipped with the interferometer for gravitational waves detection. We focus on the discovery potential of such a dark matter signal on the third-generation European gravitational waves detector, the Einstein Telescope. By taking the thickness of mirror into account, more than one resonances are predicted in the sensitive regime of high frequency interferometer. When mass of dark matter is heavier than a few PeV or is highly boosted, the signal-to-noise ratio could exceed one, and Einstein Telescope should be about to detect this dark matter signal.

    hep-phastro-ph.IMPRD(2022)·12 citations
18. 18*

    Inhomogeneous pion condensed phase hosting topologically stable baryons

    Massimo Mannarelli🇮🇹 · Fabrizio Canfora🇨🇱 · Stefano Carignano🇪🇸 · Marcela Lagos🇨🇱 · Aldo Vera🇨🇱

    We discuss the inhomogeneous pion condensed phase within the framework of chiral perturbation theory. We show how the general expression of the condensate can be obtained solving three coupled differential equations, expressing how the pion fields are modulated in space. Upon using some simplifying assumptions, we determine an analytic solution in (3+1)-dimensions. The obtained inhomogeneous condensate is characterized by a non-vanishing topological charge, which can be identified with the baryonic number. In this way, we obtain an inhomogeneous system of pions hosting an arbitrary number of baryons at fixed positions in space.

    hep-phhep-thEPJ Web Conf.(2022)·0 citations
19. 19*

    From topological amplitude to rescattering dynamics

    Di Wang🇨🇳

    We proposed a theoretical framework to correlate the topological diagram at quark level and rescattering dynamics at hadron level. In the framework, both the hadronic triangle diagram, and the topological-scattering diagram, which is the intermediate structure between topological diagram and triangle diagram, are expressed in the tensor form. The completeness of topological-scattering diagram is confirmed by the quark substructure of meson-meson scattering. The coefficient of each triangle diagram can be derived from the topological-scattering diagram and the total rescattering amplitudes are consistent with the ones derived from the chiral Lagrangian. If only the short-distance $T$ diagram is considered as the weak vertex in triangle diagram, the rescattering contributions in the $C$, $E$ and $P$ diagrams have definite proportional relation of $L(C):L(E):L(P)=-2:1:1$ under the $SU(3{)}_F$ symmetry, and the rescattering contributions in the $T$ and $A$ diagrams only arise from the $SU(3{)}_F$ breaking effects. Taking $D\to K\pi$ and $D\to \pi \pi$ modes as examples, we present our framework in detail. We find the Isospin relations in these decays are still valid in terms of triangle diagrams. Besides, the conclusions in the $D$ meson decays under the $SU(3{)}_F$ symmetry can be generalized to the $B$ meson decays under the $SU(4{)}_F$ symmetry.

    hep-phJHEP(2022)·12 citations
20. 20*

    Upcgen: a Monte Carlo simulation program for dilepton pair production in ultra-peripheral collisions of heavy ions

    Nazar Burmasov🇷🇺 · Evgeny Kryshen🇷🇺 · Paul Buehler🇦🇹 · Roman Lavicka🇦🇹

    Ultra-peripheral collisions (UPCs) of heavy ions can be used as a clean environment to study two-photon induced interactions such as dilepton pair photoproduction. Recently, precise data on lepton pair production in UPCs were obtained by the ATLAS experiment at the LHC where significant deviations, of up to 20%, from available theoretical predictions were observed. In this work, we present a Monte Carlo event generator, Upcgen, that implements a refined treatment of the photon flux allowing us to improve the agreement with ATLAS data at large dilepton rapidities. Besides, the new generator offers a possibility to study photon polarization effects and set arbitrary values of the lepton anomalous magnetic moment that can be used in the future studies of tau g-2 via ditau production measurements in UPCs.

    hep-phnucl-exnucl-thComput.Phys.Commun.(2022)·27 citations
21. 21*

    Stability of Classical Chromodynamic Fields

    Sylwia Bazak🇵🇱 · Stanislaw Mrowczynski🇵🇱

    A system of gluon fields generated at the earliest phase of relativistic heavy-ion collisions can be described in terms of classical fields. Numerical simulations show that the system is unstable but a character of the instability is not well understood. With the intention to systematically study the problem, we analyze a stability of classical chromomagnetic and chromoelectric fields which are constant and uniform. We consider the Abelian configurations discussed in the past where the fields are due to the single-color potentials linearly depending on coordinates. However, we mostly focus on the nonAbelian configurations where the fields are generated by the multi-color non-commuting constant uniform potentials. We derive a complete spectrum of small fluctuations around the background fields which obey the linearized Yang-Mills equations. The spectra of Abelian and nonAbelian configurations are similar but different and they both include unstable modes. We briefly discuss the relevance of our results for fields which are uniform only in a limited spatial domain.

    hep-phhep-thnucl-thPRD(2022)·8 citations
22. 22*

    Molecular interpretation of the LHCb pentaquarks from an analysis of $J/\psi p$ spectrum

    Meng-Lin Du🇪🇸

    A coupled-channel approach including the ${\Lambda }_c{\bar{D}}^{(\ast )}$ and ${\eta }_{c}p$ channels in addition to the ${\Sigma }_c^{(\ast )}{\bar{D}}^{(\ast )}$ and $J/\psi p$ channels, as required by unitarity and heavy quark spin symmetry (HQSS), is applied to the hidden-charm pentaquark $P_c$ states, i.e., $P_c(4312)$, $P_c(4440)$ and $P_c(4457)$, discovered by LHCb Collaboration. It is demonstrated that to obtain cutoff independent results, the one-pion exchange potential in the multichannel systems is to be supplemented with next-leading order counter terms responsible for the $S$-wave-to-$D$-wave transitions. We show that the experimental data for the $J/\psi p$ mass distributions are fully in line with the ${\Sigma }_c\bar{D}$ and ${\Sigma }_c{\bar{D}}^{\ast }$ hadronic molecular interpretation of the $P_c(4312)$ and $P_c(4440)/P_c(4457)$, respectively. A narrow ${\Sigma }_c^{\ast }\bar{D}$ molecule around 4.38 GeV is required by the HQSS with the evidence for its existence seen in the $J/\psi p$ spectrum. Moreover, we predict the line shapes for the elastic and inelastic channels.

    hep-phEPJ Web Conf.(2022)·3 citations
23. 23*

    WIMPs Without Weakness: Generalized Mass Window with Entropy Injection

    Pouya Asadi🇺🇸 · Tracy R. Slatyer🇺🇸 · Juri Smirnov🇸🇪

    We study general freeze-out scenarios where an arbitrary number of initial and final dark matter particles participate in the number-changing freeze-out interaction. We consider a simple sector with two particle species undergoing such a thermal freeze-out; one of the relics is stable and gives rise to the dark matter today, while the other one decays to the Standard Model, injecting significant entropy into the thermal bath that dilutes the dark matter abundance. We show that this setup can lead to a stable relic population that reproduces the observed dark matter abundance without requiring weak scale masses or couplings. The final dark matter abundance is estimated analytically. We carry out this calculation for arbitrary temperature dependence in the freeze-out process and identify the viable dark matter mass and cross section ranges that explain the observed dark matter abundance. This setup can be used to open parameter space for both heavy (above the unitarity bound) or light (sub-GeV) dark matter candidates. We point out that the best strategy for probing most parts of our parameter space is to look for signatures of an early matter-dominant epoch.

    hep-phastro-ph.COhep-thPRD(2022)·18 citations
24. 24*

    An Exceptional G(2) Extension of the Standard Model from the Correspondence with Cayley-Dickson Algebras Automorphism Groups

    Nicolo' Masi🇮🇹

    In this article I propose a new criterion to extend the Standard Model of particle physics from a straightforward algebraic conjecture: the symmetries of physical microscopic forces originate from the automorphism groups of main Cayley-Dickson algebras, from complex numbers to octonions and sedenions. This correspondence leads to a natural enlargement of the Standard Model color sector, from a SU(3) gauge group to an exceptional Higgs-broken G(2) group, following the octonionic automorphism relation guideline. In this picture, an additional ensemble of massive G(2)-gluons emerges, which is separated from the particle dynamics of the Standard Model.

    hep-phhep-thSci.Rep.(2021)·18 citations
25. 25*

    Notes on Confinement on ${\mathbf{R}}^3\times {\mathbf{S}}^1$: From Yang-Mills, super-Yang-Mills, and QCD(adj) to QCD(F)

    Erich Poppitz🇨🇦

    This is a pedagogical introduction to the physics of confinement on $R^3\times S^1$, using $SU(2)$ Yang-Mills with massive or massless adjoint fermions as the prime example; at the end, we also add fundamental flavours. The small-$S^1$ limit is remarkable, allowing for controlled semiclassical determination of the nonperturbative physics in these, mostly non-supersymmetric, theories. We begin by reviewing the Polyakov confinement mechanism on $R^3$. Moving on to $R^3\times S^1$, we show how introducing adjoint fermions stabilizes center symmetry, leading to abelianization and semiclassical calculability. We explain how monopole-instantons and twisted monopole-instantons arise. We describe the role of various novel topological excitations in extending Polyakov's confinement to the locally four-dimensional case, discuss the nature of the confining string, and the $\theta$-angle dependence.~We study the global symmetry realization and, when available, present evidence for the absence of phase transitions as a function of the $S^1$ size. As our aim is not to cover all work on the subject, but to prepare the interested reader for its study, we also include brief descriptions of topics not covered in detail: the necessity for analytic continuation of path integrals, the study of more general theories, and the 't Hooft anomalies involving higher-form symmetries.

    ↳ hep-thhep-lathep-phSymmetry(2022)·43 citations
26. 26*

    A New Model of Intranuclear Neutron-Antineutron Transformations in ${}_8^{16}$O

    J. L. Barrow🇺🇸 · A. S. Botvina🇷🇺 · E. S. Golubeva🇷🇺 · J-M. Richard🇫🇷

    There has been much work in recent years pertaining to viability studies for the intranuclear observation of neutron-antineutron transformations. These studies begin firstly with the design and implementation of an event generator for the simulation of this rare process, where one hopes to retain as much of the underlying nuclear physics as possible in the initial state, and then studying how these effects may perturb the final state observable particles for detector efficiency studies following simulated reconstruction. There have been several searches for intranuclear neutron-antineutron transformations, primarily utilizing the ${}_8^{16}$O nucleus, and completed within large underground water Cherenkov detectors such as Super-Kamiokande. The latest iteration of a generator is presented here for use in such an experiment. This generator includes several new features, including a new radial (position) annihilation probability distribution and related intranuclear suppression factor for ${}_8^{16}$O, as well as a highly general, modern nuclear multifragmentation model with photonic de-excitations. The latter of these may allow for improved identification of the signal using large underground detectors such as Super-Kamiokande and the future Hyper-Kamiokande, potentially increasing the overall signal efficiencies of these rare searches. However, it should be noted that certain fast photonic de-excitations may be washed out by ${\pi }^0$ decays to photons. These new features implemented in these $\bar{n}$\isotope[15][8]{O} simulations increase the overall physical realism of the model, and are easily portable to other future searches such as to extranuclear $\bar{n}{}_6^{12}$C for the ESS NNBAR experiment, as well as intranuclear $\bar{n}{}_{18}^{39}$Ar used in DUNE.

    ↳ hep-exhep-phnucl-thPRC(2022)·5 citations
27. 27*

    Pulsar Polarization Arrays

    Tao Liu🇨🇳 · Xuzixiang Lou🇨🇳 · Jing Ren🇨🇳

    Pulsar timing arrays (PTAs) consisting of widely distributed and well-timed millisecond pulsars can serve as a galactic interferometer to measure gravitational waves. With the same data acquired for PTAs, we propose to develop pulsar polarization arrays (PPAs), to explore astrophysics and fundamental physics. As in the case of PTAs, PPAs are best suited to reveal temporal and spatial correlations at large scales that are hard to mimic by local noise. To demonstrate the physical potential of PPAs, we consider detection of ultralight axion-like dark matter (ALDM), through cosmic birefringence induced by its Chern-Simon coupling. Because of its tiny mass, the ultralight ALDM can be generated as a Bose-Einstein condensate, characterized by a strong wavy nature. Incorporating both temporal and spatial correlations of the signal, we show that PPAs have a potential to probe the Chern-Simon coupling up to $\sim 10^{-14}-10^{-17}$GeV${}^{-1}$, with a mass range $\sim 10^{-27}-10^{-21}$eV.

    ↳ astro-ph.HEastro-ph.COastro-ph.IMhep-phPRL(2023)·51 citations
28. 28*

    Effective Field Theories and Lattice QCD for the X Y Z frontier

    Nora Brambilla🇩🇪

    Exotic states have been predicted before and after the advent of QCD. In the last decades they have been observed at accelerator experiments in the sector with two heavy quarks, at or above the quarkonium strong decay threshold and called X Y Z states. These states offer a unique possibility for investigating the dynamical properties of strongly correlated systems in QCD. I will show how an alliance of nonrelativistic effective field theories and lattice can allow us to address these states in QCD. In particular I will explain what are the opportunities and challenges of lattice QCD in this respect and which new tools should be developed.

    ↳ hep-lathep-phhep-thnucl-thPoS(2022)·13 citations
29. 29*

    Modulation of pulse profile as a signal for phase transitions in a pulsar core

    Partha Bagchi🇨🇳 · Biswanath Layek🇮🇳 · Anjishnu Sarkar🇮🇳 · Ajit M. Srivastava🇮🇳

    We calculate detailed modification of pulses from a pulsar arising from the effects of phase transition induced density fluctuations on the pulsar moment of inertia. We represent general statistical density fluctuations using a simple model where the initial moment of inertia tensor of the pulsar (taken to be diagonal here) is assumed to get random additional contributions for each of its component which are taken to be Gaussian distributed with certain width characterized by the strength of density fluctuations $ϵ$. Using sample values of $ϵ$, (and the pulsar deformation parameter $\eta$) we numerically calculate detailed pulse modifications by solving Euler's equations for the rotational dynamics of the pulsar. We also give analytical estimates which can be used for arbitrary values of $ϵ$ and $\eta$. We show that there are very specific patterns in the perturbed pulses which are observable in terms of modulations of pulses over large time periods. In view of the fact that density fluctuations fade away eventually leading to a uniform phase in the interior of pulsar, the off-diagonal components of MI tensor also vanish eventually. Thus, the modification of pulses due to induced wobbling (from the off-diagonal MI components) will also die away eventually. This allows one to distinguish these transient pulse modulations from the effects of any wobbling originally present. Further, the decay of these modulations in time directly relates to relaxation of density fluctuations in the pulsar giving valuable information about the nature of phase transition occurring inside the pulsar.

    ↳ astro-ph.HEhep-phnucl-exnucl-thMNRAS(2022)·5 citations
30. 30*

    Anomaly of non-Abelian discrete symmetries

    Tatsuo Kobayashi🇯🇵 · Hikaru Uchida🇯🇵

    We study anomalies of non-Abelian discrete symmetries; which part of non-Abelian group is anomaly free and which part can be anomalous. It is found that the anomaly-free elements of the group $G$ generate a normal subgroup $G_0$ of $G$ and the residue class group $G/G_0$, which becomes the anomalous part of $G$, is isomorphic to a single cyclic group. The derived subgroup $D(G)$ of $G$ is useful to study the anomaly structure. This structure also constrains the structure of the anomaly-free subgroup; the derived subgroup $D(G)$ should be included in the anomaly-free subgroup. We study the detail structure of the anomaly-free subgroup from the structure of the derived subgroup in various discrete groups. For example, when $G=S_n\simeq A_n⋊Z_2$ and $G=\Delta (6n^2)\simeq \Delta (3n^2)⋊Z_2$, in particular, $A_n$ and $\Delta (3n^2)$ are at least included in the anomaly-free subgroup, respectively. This result holds in any arbitrary representations.

    ↳ hep-thhep-phPRD(2022)·13 citations
31. 31*

    (P)reheating Effects of the Kähler Moduli Inflation I Model

    Islam Khan🇺🇸 · Aaron C. Vincent🇨🇦 · Guy Worthey🇺🇸

    We investigate reheating in the string-theory-motivated Kähler Moduli Inflation I (KMII) potential, coupled to a light scalar field $\chi$ and produce constraints and forecasts based on Cosmic Microwave Background (CMB) and gravitational wave observables. We implement a Markov Chain Monte Carlo (MCMC) sampling method to compute the adopted model's parameter ranges allowed by the current CMB observations. Floquet analysis and numerical lattice simulations are performed to analyze the nonlinear effects of the model's (p)reheating phase. We derive bounds on the $\Lambda$CDM parameters $A_s$, $n_s$, $n_{\mathrm{run}}$, and $r$ based on \textit{Planck} results, finding that correlations between model parameters severely constrain the range of these parameters allowed within this model. While the KMII potential's non-vanishing minimum may provide a possible source for the observed dark energy density ${\rho }_{\mathrm{DE}}$ this cannot be tested with current observations. We estimate the $95\%$ CI bounds on the inflaton mass $m_{\varphi }$ and reheating temperature $T_{\mathrm{reh}}$ to be $2.1\times 10^{13}\mathrm{GeV}\lesssim m_{\varphi }\lesssim 3.2\times 10^{13}\mathrm{GeV}$ and $T_{\mathrm{reh}}\gtrsim 1.8\times 10^3\mathrm{GeV}$, respectively. We observe {both} self-resonance and parametric resonance instability band structures in our Floquet analysis results. Finally, we do not observe any formation of oscillon configurations in our lattice simulations; however, our results predict a stochastic gravitational wave background generated during preheating that would be observable today in the $10^9$ - $10^{11}\mathrm{Hz}$ frequency range.

    ↳ astro-ph.COhep-phPRD(2023)·5 citations
32. 32*

    Parity from gauge symmetry

    Alessio Maiezza🇭🇷 · Fabrizio Nesti🇮🇹

    We argue that Left-Right parity symmetry $\mathcal{P}$ can arise as a discrete remnant of a unified gauge symmetry. The high-energy unification necessarily includes the gauging of the Lorentz symmetry, bringing into the game gravitational interactions, and leading to a gravi-GUT scheme. Parity emerges unbroken below the Planck scale, and can be broken spontaneously at lower energies making contact with the Standard Model. This framework motivates the spontaneous origin of parity violation as in Left-Right symmetric theories with $\mathcal{P}$. The possible unifying gauge groups are identified as SO(1,7) for gravitational and weak interactions, or SO(7,7) for a complete unification.

    ↳ hep-thgr-qchep-phEPJC(2022)·13 citations
33. 33*

    Lepton Flavour Universality tests and Lepton Flavour Violation searches at LHCb

    Sara Celani🇨🇭

    The Standard Model (SM) of particle physics represents our most fundamental knowledge of elementary particles and their interactions. One of the cardinal properties of the SM which has been thoroughly studied during the past years is the so-called Lepton Flavour Universality (LFU): W and Z bosons are predicted to be equally coupled to the three lepton generations. Hints for deviations from LFU have been found by the LHCb collaboration in $b\to s\ell \ell$ and $b\to c\ell \nu$ decays, sparking great interest and further motivating the searches for lepton flavour violating processes. A general review of these results is presented, including prospects in view of the LHC and LHCb upgrade.

    ↳ hep-exhep-phSciPost Phys.Proc.(2025)·3 citations
34. 34*

    Phases of Confining SU(5) Chiral Gauge Theory with Three Generations

    Yang Bai🇺🇸 · Daniel Stolarski🇨🇦

    We explore the possible low energy phases of the confining non-supersymmetric $SU(5)$ chiral gauge theory with three generations of fermions in the $(10+\bar{5})$ representations. This theory has the same fermion and gauge matter content as the simplest Georgi-Glashow grand unified theory of the Standard Model and has an $SU(3)\times SU(3)\times U(1)$ global symmetry. Using 't Hooft anomaly matching, most attractive channel, and soft SUSY breaking approaches, we outline a number of possible consistent low energy vacua including one with a remnant $SO(3)\times U(1)$ symmetry that is analogous to the one-generation model. For the soft SUSY breaking approach, we find that as one extrapolates to large SUSY breaking to recover the original theory, a phase transition is possible. We show that such a phase transition is guaranteed if SUSY breaking is communicated via anomaly mediation.

    ↳ hep-thhep-phJHEP(2022)·20 citations
35. 35*

    Phase diagram of QCD in a magnetic background

    Massimo D'Elia🇮🇹 · Lorenzo Maio🇮🇹 · Francesco Sanfilippo🇮🇹 · Alfredo Stanzione🇮🇹

    We provide numerical evidence that the thermal QCD crossover turns into a first order transition in the presence of large enough magnetic background fields. The critical endpoint is found to be located between $eB=4$ GeV${}^2$ (where the pseudocritical temperature is $T_c=(98\pm 3)$ MeV) and $eB=9$ GeV${}^2$ (where the critical temperature is $T_c=(63\pm 5)$ MeV). Results are based on the analysis of quark condensates and number susceptibilities, determined by lattice simulations of $N_f=2+1$ QCD at the physical point, discretized with three different lattice spacings, $a=0.114,0.086$ and $0.057$ fm, via rooted stout staggered fermions and a Symanzik tree level improved pure gauge action. We also present preliminary results regarding the confining properties of the thermal theory, suggesting that they could change drastically going across the phase transition

    ↳ hep-lathep-phhep-thPRD(2022)·76 citations
36. 36*

    Studies of the Earth shielding effect to direct dark matter searches at the China Jinping Underground Laboratory

    Z. Z. Liu · L. T. Yang · Q. Yue · C. H. Yeh · K. J. Kang · Y. J. Li · M. Agartioglu · H. P. An · J. P. Chang · J. H. Chen · Y. H. Chen · J. P. Cheng and 71 other authors

    Dark matter direct detection experiments mostly operate at deep underground laboratories. It is necessary to consider shielding effect of the Earth, especially for dark matter particles interacting with a large cross section. We analyzed and simulated the Earth shielding effect for dark matter at the China Jinping Underground Laboratory (CJPL) with a simulation package, CJPL Earth Shielding Simulation code (CJPL\_ESS), which is applicable to other underground locations. The further constraints on the $\chi$-N cross section exclusion regions are derived based on the studies with CDEX experiment data.

    ↳ hep-exhep-phphysics.ins-detPRD(2022)·52 citations
37. 37*

    The data-driven future of high energy density physics

    Peter W. Hatfield🇬🇧 · Jim A. Gaffney🇺🇸 · Gemma J. Anderson🇺🇸 · Suzanne Ali🇺🇸 · Luca Antonelli🇬🇧 · Suzan Başeğmez du Pree🇳🇱 · Jonathan Citrin🇳🇱 · Marta Fajardo🇵🇹 · Patrick Knapp🇺🇸 · Brendan Kettle🇬🇧 · Bogdan Kustowski🇺🇸 · Michael J. MacDonald🇺🇸 and 11 other authors

    The study of plasma physics under conditions of extreme temperatures, densities and electromagnetic field strengths is significant for our understanding of astrophysics, nuclear fusion and fundamental physics. These extreme physical systems are strongly non-linear and very difficult to understand theoretically or optimize experimentally. Here, we argue that machine learning models and data-driven methods are in the process of reshaping our exploration of these extreme systems that have hitherto proven far too non-linear for human researchers. From a fundamental perspective, our understanding can be helped by the way in which machine learning models can rapidly discover complex interactions in large data sets. From a practical point of view, the newest generation of extreme physics facilities can perform experiments multiple times a second (as opposed to ~daily), moving away from human-based control towards automatic control based on real-time interpretation of diagnostic data and updates of the physics model. To make the most of these emerging opportunities, we advance proposals for the community in terms of research design, training, best practices, and support for synthetic diagnostics and data analysis.

    ↳ physics.plasm-phhep-phNature·14 citations
38. 38*

    Measurement of the 1-jettiness in deep-inelastic scattering at HERA

    Johannes Hessler

    A first measurement of the 1-jettiness event shape observable ${\tau }_1^b$ in neutral-current deep inelastic scattering is presented. For the measurement, the equivalence of ${\tau }_1^b$ to the DIS thrust observable defined in the Breit frame is utilised. The data were taken by the H1 experiment at HERA from 2003 to 2007 at a centre of mass energy of $\sqrt{s}=319\text{ GeV}$. The data amount to an integrated luminosity of $351.6{\text{ pb}}^{-1}$. The triple-differential cross sections are presented as a function of the 1-jettiness ${\tau }_b^1$, the virtuality of the exchanged boson $Q^2$ and the inelasticity of the event $y$. The data exhibit a sensitivity to the strong coupling constant and to resummation and hadronisation effects, as well as to the parton distribution functions of the proton. The data are compared to selected predictions.

    ↳ hep-exhep-phPoS(2022)·6 citations
39. 39*

    Anomalous plasma: chiral magnetic effect and all that

    Igor A. Shovkovy🇺🇸

    Chiral anomalous effects in relativistic plasmas are reviewed. The essence of chiral separation and chiral magnetic effects is explained in simple terms. Qualitative differences between the two phenomena, both of which are triggered by background electromagnetic fields, are highlighted. It is shown how an interplay of the chiral separation and chiral magnetic effects could lead to a new collective plasma mode, called the chiral magnetic wave. It is argued that the chiral magnetic wave is overdamped in weakly interacting plasmas. Its fate in a strongly interacting quark-gluon plasma is less clear, especially in the presence of a superstrong magnetic field. The observational signatures of the chiral anomalous effects are discussed briefly.

    ↳ nucl-thhep-phChapter 18 in Peter Suranyi 87th Birthday…·9 citations
40. 40*

    One-loop matching for quark dipole operators in a gradient-flow scheme

    Emanuele Mereghetti🇺🇸 · Christopher J. Monahan🇺🇸 · Matthew D. Rizik🇺🇸 · Andrea Shindler🇺🇸 · Peter Stoffer🇨🇭

    The quark chromoelectric dipole (qCEDM) operator is a CP-violating operator describing, at hadronic energies, beyond-the-standard-model contributions to the electric dipole moment of particles with nonzero spin. In this paper we define renormalized dipole operators in a regularization-independent scheme using the gradient flow, and we perform the matching at one loop in perturbation theory to renormalized operators of the same and lower dimension in the more familiar MS scheme. We also determine the matching coefficients for the quark chromomagnetic dipole operator (qCMDM), which contributes, for example, to matrix elements relevant to CP-violating and CP-conserving kaon decays. The calculation provides a basis for future lattice QCD computations of hadronic matrix elements of the qCEDM and qCMDM operators.

    ↳ hep-lathep-exhep-phJHEP(2022)·35 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.