Tue·Nov 8, 2022Tuesday·November 8, 2022

1. 01*

   Taming New Physics in $b\to c\bar{u}d(s)$ with $\tau (B^{+})/\tau (B_d)$ and $a_{sl}^d$

   Alexander Lenz🇩🇪 · Jakob Müller🇩🇪 · Maria Laura Piscopo🇩🇪 · Aleksey V. Rusov🇩🇪

   Inspired by the recently observed tensions between the experimental data and the theoretical predictions, based on QCD factorisation, for several colour-allowed non-leptonic $B$-meson decays, we study the potential size of new physics (NP) effects in the decay channels $b\to c\bar{u}d(s)$. Starting from the most general effective Hamiltonian describing the $b\to c\bar{u}d(s)$ transitions, we compute NP contributions to the theoretical predictions of $B$-meson lifetime and of $B$-mixing observables. The well-known lifetime ratio $\tau (B^{+})/\tau (B_d)$ and the experimental bound on the semi-leptonic CP asymmetry $a_{sl}^d$, provide strong, complementary constraints on some of the NP Wilson coefficients.

   hep-phhep-exJHEP(2023)·24 citations
2. 02*

   The Electron-Ion Collider -- A U.S. facility for the European community to explore the mysteries of the building blocks of matter

   Marco Radici🇮🇹 · Silvia Dalla Torre🇮🇹 · Daria Sokhan🇫🇷

   This document is submitted as input to the NuPECC Long Range Plan 2024 by three European members of the EIC Users Group Steering Committee (Vice Chair, one at-large member, and the EU Representative). We submit the document on behalf of the international EIC Users Group (EICUG) community, but we specifically represent 335 European members of the EICUG (25%) based in 80 institutions (30% of the total) located in Armenia, Czech Republic, Finland, France, Germany, Hungary, Ireland, Israel, Italy, Netherlands, Norway, Poland, Slovenia, Spain, Sweden, Switzerland, Ukraine, and the United Kingdom. This European involvement is an important driver of the EIC, but can also be beneficial for a number of related ongoing and planned nuclear physics experiments in Europe. In this document, the shared interest regarding scientific questions and detector R&D between the EIC and European nuclear physics communities is outlined. The aim is to highlight how these synergies offer ample opportunities to foster progress at the forefront of nuclear physics.

   hep-phhep-exnucl-exnucl-th1 citation
3. 03*

   The Decomposition of Neutron-Antineutron Oscillation Operators

   Shao-Long Chen🇨🇳 · Yu-Qi Xiao🇨🇳

   We study the systematic decomposition of the dimension nine neutron-antineutron oscillation operators at tree and one-loop levels. We discuss the topologies' generation and the assignment of the chiral quarks. The completed lists of the decompositions are provided. We furthermore show an example that the neutron-antineutron oscillation occurs at one-loop level, with the tiny neutrino mass being generated via the scotogenic model and proton decay being evaded.

   hep-phJHEP(2023)·3 citations
4. 04*

   Multi-variable Integration with a Neural Network

   Daniel Maître🇬🇧 · Roi Santos-Mateos🇪🇸

   In this article we present a method for automatic integration of parametric integrals over the unit hypercube using a neural network. The method fits a neural network to the primitive of the integrand using a loss function designed to minimize the difference between multiple derivatives of the network and the function to be integrated. We apply this method to two example integrals resulting from the sector decomposition of a one-loop and two-loop scalar integrals. Our method can achieve per-mil and percent accuracy for these integrals over a range of invariant values. Once the neural network is fitted, the evaluation of the integral is between 40 and 125 times faster than the usual numerical integration method for our examples, and we expect the speed gain to increase with the complexity of the integrand.

   hep-phJHEP(2023)·15 citations
5. 05*

   Axion-meson mixing in light of recent lattice $\eta$-${\eta }^{\prime }$ simulations and their two-photon couplings within $U(3)$ chiral theory

   Rui Gao🇨🇳 · Zhi-Hui Guo🇨🇳 · J.A. Oller🇪🇸 · Hai-Qing Zhou🇨🇳

   We study the mixing of the QCD/QCD-like axion and light-flavor mesons ${\pi }^0,\eta ,{\eta }^{\prime }$ within the framework of $U(3)$ chiral perturbation theory up to next-to-leading order in this work. The axion-meson mixing formulas are calculated order by order in the $U(3)$ $\delta$-expansion scheme, namely the joint expansions of the momentum, light-quark masses and $1/N_C$. We provide axion-meson mixing relations in terms of the ${\pi }^0$-$\eta$-${\eta }^{\prime }$ mixing parameters and their masses. The recent lattice simulations on the $\eta$-${\eta }^{\prime }$ systems turn out to be able to offer valuable inputs to constrain the unknown low-energy constants. The relation of the mass and decay constant of the axion is then further explored based on our updated calculations. The two-photon couplings of the light-flavor mesons, together with the axion, are also investigated in the $U(3)$ chiral theory up to next-to-leading order in the $\delta$-counting scheme.

   hep-phJHEP(2023)·22 citations
6. 06*

   Investigations on the light hadron decays of $Z_b(10610)$ and $Z_b(10650)$

   Qi Wu🇨🇳 · Yuanxin Zheng🇨🇳 · Shidong Liu🇨🇳 · Gang Li🇨🇳

   The light hadron decay processes of $Z_b(10610)/Z_b(10650)$ provide us a way to study their nature and decay mechanism. In this work, we evaluate the branching ratios of $Z_b(10610)/Z_b(10650)\to VP$ ($V$ and $P$ stand for light vector and pseudoscalar mesons, respectively) using an effective Lagrangian approach, in which the contributions of intermediate bottomed meson triangle loops are considered. In our calculations, the $Z_b(10610)$ and $Z_b(10650)$ are regarded as $B{\bar{B}}^{\ast }+c.c.$ and $B^{\ast }{\bar{B}}^{\ast }$ molecular states, respectively. The predicted branching ratios of $Z_b(10610)\to VP$ are about in the order of $10^{-2}$, while the branching ratios of $Z_b(10650)\to VP$ are in the order of $10^{-3}$. Furthermore, the dependence of these ratios between different decay modes of $Z_b(10610)/Z_b(10650)$ on the mixing $\eta -{\eta }^{\prime }$ angle ${\theta }_P$ is investigated, which may be a good quantity for the experiments. It is hoped that the calculations here could be tested by future experiments.

   hep-phPRD(2023)·12 citations
7. 07*

   Quark generalized TMDs at skewness and Wigner Distribution in boost invariant longitudinal space

   Vikash Kumar Ojha🇮🇳 · Sujit Jana🇮🇳 · Tanmay Maji🇮🇳

   The boost-invariant longitudinal space, defined by the parameter $\sigma =\frac{1}{2}{b}^{-}{P}^{+}$ can be studied from the Fourier transformation of distributions over the conjugate variable skewness $\xi$. We investigate quark Wigner distributions in the $\sigma$ space in dressed quark model and found diffraction patterns that are analogous to the single slit experiment of light in optics. The width of the central maxima varies with energy transfer to the system and essentially $\xi$ behaves like a slit-width. Qualitatively similar diffraction pattern is reported recently in other models. In this model, we compute all the leading twist GTMDs with non-zero skewness for quarks which provides Wigner distributions under Fourier transformation.

   hep-phPRD(2023)·19 citations
8. 08*

   From five-loop scattering amplitudes to open trees with the Loop-Tree Duality

   Selomit Ramírez-Uribe🇪🇸 · Roger J. Hernández-Pinto🇲🇽 · Germán Rodrigo🇪🇸 · German F. R. Sborlini🇪🇸

   Characterizing multiloop topologies is an important step towards developing novel methods at high perturbative orders in quantum field theory. In this article, we exploit the Loop-Tree Duality (LTD) formalism to analyse multiloop topologies that appear for the first time at five loops. Explicitly, we open the loops into connected trees and group them according to their topological properties. Then, we identify a kernel generator, the so-called N${}^7$MLT universal topology, that allow us to describe any scattering amplitude of up to five loops. Furthermore, we provide factorization and recursion relations that enable us to write these multiloop topologies in terms of simpler subtopologies, including several subsets of Feynman diagrams with an arbitrary number of loops. Our approach takes advantage of many symmetries present in the graphical description of the original fundamental five-loop topologies. The results obtained in this article might shed light into a more efficient determination of higher-order corrections to the running couplings, which are crucial in the current and future precision physics program.

   hep-phSymmetry(2022)·13 citations
9. 09*

   Fitting a Collider in a Quantum Computer: Tackling the Challenges of Quantum Machine Learning for Big Datasets

   Miguel Caçador Peixoto🇵🇹 · Nuno Filipe Castro🇵🇹 · Miguel Crispim Romão🇵🇹 · Maria Gabriela Jordão Oliveira🇵🇹 · Inês Ochoa🇵🇹

   Current quantum systems have significant limitations affecting the processing of large datasets with high dimensionality, typical of high energy physics. In the present paper, feature and data prototype selection techniques were studied to tackle this challenge. A grid search was performed and quantum machine learning models were trained and benchmarked against classical shallow machine learning methods, trained both in the reduced and the complete datasets. The performance of the quantum algorithms was found to be comparable to the classical ones, even when using large datasets. Sequential Backward Selection and Principal Component Analysis techniques were used for feature's selection and while the former can produce the better quantum machine learning models in specific cases, it is more unstable. Additionally, we show that such variability in the results is caused by the use of discrete variables, highlighting the suitability of Principal Component analysis transformed data for quantum machine learning applications in the high energy physics context.

   hep-phhep-exphysics.data-anquant-phFront.Artif.Intell.(2023)·13 citations
10. 10*

    Space-time variation of the s and c quark masses

    V.V. Flambaum🇦🇺 · P. Munro-Laylim🇦🇺

    Space-time variation of fundamental physical constants in expanding Universe is predicted by a number of popular models. The masses of second generation quarks are larger than first generation quark masses by several orders of magnitude, therefore space-time variation in quark masses may significantly vary between each generation. We evaluate limits on variation in the s and c quark masses from Big Bang nucleosynthesis, Oklo natural nuclear reactor, Yb+, Cs and Rb clock data. The construction of 229Th nuclear clock is expected to enhance these limits by several orders of magnitude. Furthermore, constraints are obtained on an oscillating scalar or pseudoscalar cold dark matter field, as interactions of the field with quarks produce variations in quark masses.

    hep-phastro-ph.COnucl-thphysics.atom-phPRD(2023)·6 citations
11. 11*

    Anisotropic gravitational waves induced by hypermagnetic fields during the electroweak phase transition epoch

    Mingqiu Li🇨🇳 · Qi-Shu Yan🇨🇳 · Mei Huang🇨🇳

    We study the anisotropies of gravitational waves induced by weak hypermagnetic fields which are randomly distributed and oriented during the electroweak phase transition in the early universe. The theory setup of this study is the standard model plus a real singlet scalar field, which can produce the needed strongly first order electroweak phase transition. Then we investigate how the hypermagnetic fields can convert to magnetic fields and we compute the departure of energy difference between the symmetric phase and the broken phase when the magnetic fields are turned on. It is found that the presence of the hypermagnetic fields can increase the Euclidean action, thus can decrease nucleation temperature, which can lead to a supercool plasma. We point out that the hypermagnetic field can enhance the gravitational wave production from a first order electroweak phase transition and the inhomogeneity of primordial hypermagnetic field can lead to anisotropies of gravitational waves. By examining three well-motivated distribution of hypermagnetic fields, we calculate the corresponding angular power spectra of stochastic gravitational wave background and find they can be significantly larger than the contributions of the Sachs-Wolfe effects and integrated Sachs-Wolfe effects. Our results show that the anisotropies of gravitational wave could provide a novel probe to the primordial hypermagnetic field in the electroweak phase transition epoch.

    hep-phastro-ph.COPRD(2023)·4 citations
12. 12*

    Revealing the Signal of QCD Phase Transition in Heavy-Ion Collisions

    Yi Lu🇨🇳 · Fei Gao🇨🇳 · Xiaofeng Luo🇨🇳 · Lei Chang🇨🇳 · Yu-xin Liu🇨🇳

    We propose a novel method to construct the Landau thermodynamic potential directly from the fluctuations measured in heavy-ion collisions. The potential is capable of revealing the signal of the critical end-point (CEP) and the first order phase transition (FOPT) of QCD in the system even away from the phase transition region. With the available experimental data, we show that the criterion of the FOPT is negative for most of the collision energies which indicates no signal of FOPT. The data at $\sqrt{s_{\mathrm{NN}}}=7.7$ GeV with 0-5% centrality shows a different behavior and the mean value of the data satisfies the criterion. However, the uncertainty is still too large to make a certain conclusion. The higher order fluctuations are also required for confirming the signal. We emphasize therefore that new measurements with higher precision for the $C_{1,...,6}$ within 0-5% centrality in the vicinity of $\sqrt{s_{\mathrm{NN}}}=7.7$ GeV are in demand which may finally reveal the signal of QCD phase transition.

    hep-phnucl-exnucl-th1 citation
13. 13*

    Quantum SMEFT tomography: top quark pair

    Luca Mantani🇬🇧

    In recent years, an interest in the study of quantum information has grown within the high-energy particle physics community. The possibility to establish the presence of entanglement at particle colliders, such as the Large Hadron Collider (LHC) at CERN, is a novel and thrilling research direction, offering the opportunity to push quantum mechanics to its limits by using the heaviest fundamental particle: the top quark. With this in mind, we propose to use measurements of quantum entanglement to probe the behaviour of fundamental interactions and to search for New Physics at high energy within the Standard Model Effective Field Theory paradigm. Inspired by recent proposals to measure entanglement of top quark pairs produced at the LHC, we examine how the existence of new interactions between fundamental particles modify the Standard Model expectations. By performing analytical calculations, we unveil a non-trivial pattern of effects depending on the kinematical phase space configurations.

    hep-phPoS·2 citations
14. 14*

    Sterile Neutrinos: Propagation in Matter and Sensitivity to Sterile Mass Ordering

    Dibya S. Chattopadhyay🇮🇳 · Moon Moon Devi🇮🇳 · Amol Dighe🇮🇳 · Debajyoti Dutta🇮🇳 · Dipyaman Pramanik🇧🇷 · Sushant K. Raut🇮🇳

    We analytically calculate the neutrino conversion probability $P_{\mu e}$ in the presence of sterile neutrinos, with exact dependence on $\Delta m_{41}^2$ and with matter effects explicitly included. Using perturbative expansion in small parameters, the terms involving the small mixing angles ${\theta }_{24}$ and ${\theta }_{34}$ can be separated out, with ${\theta }_{34}$ dependence only arising due to matter effects. We express $P_{\mu e}$ in terms of the quantities of the form $\sin (x)/x$, which helps in elucidating its dependence on matter effects and a wide range of $\Delta m_{41}^2$ values. Our analytic expressions allow us to predict the effects of the sign of $\Delta m_{41}^2$ at a long baseline experiment like DUNE. We numerically calculate the sensitivity of DUNE to the sterile mass ordering and find that this sensitivity can be significant in the range $|\Delta m_{41}^2|\sim (10^{-4}-10^{-2})$ eV${}^2$, for either mass ordering of active neutrinos. The dependence of this sensitivity on the value of $\Delta m_{41}^2$ for all mass ordering combinations can be explained by investigating the resonance-like terms appearing due to the interplay between the sterile sector and matter effects.

    hep-phhep-exJHEP(2023)·9 citations
15. 15*

    Proton structure functions at NLO in the dipole picture with massive quarks

    Henri Hänninen🇫🇮 · Heikki Mäntysaari🇫🇮 · Risto Paatelainen🇫🇮 · Jani Penttala🇫🇮

    We predict heavy quark production cross sections in Deep Inelastic Scattering at high energy by applying the Color Glass Condensate effective theory. We demonstrate that when the calculation is performed consistently at next-to-leading order accuracy with massive quarks it becomes possible, for the first time in the dipole picture with perturbatively calculated center-of-mass energy evolution, to simultaneously describe both light and heavy quark production data at small $x_{\mathrm{Bj}}$. We furthermore show how the heavy quark cross section data provides additional strong constraints on the extracted non-perturbative initial condition for the small-$x_{\mathrm{Bj}}$ evolution equations.

    hep-phnucl-thPRL(2023)·41 citations
16. 16*

    A coupled-channel system with anomalous thresholds and unitarity

    Csaba L. Korpa🇭🇺 · Matthias F.M. Lutz🇩🇪 · Xiao-Yu Guo🇨🇳 · Yonggoo Heo🇩🇪

    We consider the isospin one-half example system, with $D\pi ,D\eta ,D_s\bar{K},D^{\ast }\pi ,D^{\ast }\eta ,D^{\ast }\bar{K}$ coupled channels in the $J^P=1^{-}$ partial wave, chosen such that various phenomena that come with the opening of an anomalous threshold can be illustrated in a step-wise procedure by a suitable variation of up, down and strange quark masses. We use a set of LEC in the chiral Lagrangian that were adjusted to a large set of Lattice QCD results. The six phase shifts and inelasticity parameters are presented for various choices of the pion mass. For a pion mass of 150 MeV there are no anomalous thresholds encountered. The small change from 150 MeV to 145 MeV pion mass causes a dramatic impact of the anomalous threshold on the phase shifts.

    hep-phhep-latnucl-thPRD(2023)·10 citations
17. 17*

    EW one-loop corrections to the longitudinally polarized Drell--Yan scattering. (I). The Neutral current case

    S. Bondarenko (1)🇷🇺 · Ya. Dydyshka (2,3)🇷🇺 · L. Kalinovskaya (2)🇷🇺 · R. Sadykov (2)🇷🇺 · V. Yermolchyk (2,3) ((1) Bogoliubov Laboratory of Theoretical Physics, JINR, 141980 Dubna, Moscow region, Russia, (2) Dzhelepov Laboratory of Nuclear Problems, JINR, 141980 Dubna, Moscow region, Russia, (3) Institute for Nuclear Problems, Belarusian State University, Minsk, 220006 Belarus)🇷🇺

    Complete one-loop electroweak corrections to neutral current Drell-Yan process $pp\to {\ell }^{+}{\ell }^{-}X$ are presented for the case of longitudinal polarization of initial particles. Cross sections for longitudinally polarized protons allow us to estimate different combinations of polarized quark distributions from single- and double-spin asymmetries. Numerical impact of electroweak next-order corrections to asymmetries as function of the vector boson rapidity and lepton pseudorapidities in the hadron-hadron centre-of-mass frame using the MC generator ReneSANCe is thoroughly studied.

    hep-phPhys.Part.Nucl.Lett.(2023)·2 citations
18. 18*

    Sunrise integral in non-relativistic QCD with elliptics

    A.V. Kotikov🇷🇺

    The main steps of the process of obtaining the result [1] in terms of elliptic polylogarithms for a two-loop sunrise integral with two different internal masses with pseudothreshold kinematics for all orders of the dimensional regulator are shown.

    hep-phPhys.Part.Nucl.Lett.(2023)·0 citations
19. 19*

    Four-loop HQET propagators from the DRA method

    Roman N. Lee🇷🇺 · Andrey F. Pikelner🇷🇺

    We use dimensional recurrence relations and analyticity to calculate four-loop propagator-type master integrals in the heavy-quark effective theory. Compared to previous applications of the DRA method, we apply a new technique of fixing homogeneous solutions from pole parts of integrals evaluated in different rational space-time dimension points. The latter were calculated from the integration-by-parts reduction of finite integrals in shifted space-time dimension and/or with increased propagators powers. We provide results for epsilon expansions of master integrals near $d=4$ and $d=3$ using constructed alternative sets of integrals with expansion coefficients having conjectural uniform transcendental weight.

    hep-phhep-thJHEP(2023)·8 citations
20. 20*

    Towards the global fit of the TMD gluon density in the proton from the LHC data

    A.V. Lipatov🇷🇺 · G.I. Lykasov🇷🇺 · M.A. Malyshev🇷🇺

    We propose a new analytical expression for the Transverse Momentum Dependent (TMD, or unintegrated) gluon density in the proton. Essential phenomenological parameters are extracted from the LHC data on inclusive hadron production in $pp$ collisions at low transverse momenta, $p_T\sim 1$~GeV. The latter are described in the framework of modified soft quark-gluon string model, where gluonic state and non-zero transverse momentum of partons inside the proton are taken into account. To determine the parameters important at moderate and large $x$ we used measurements of inclusive $b$-jet and Higgs boson production at the LHC as well as latest HERA data on proton structure functions $F_2^c(x,Q^2)$ and $F_2^b(x,Q^2)$ and reduced cross sections ${\sigma }_{\mathrm{red}}^c(x,Q^2)$ and ${\sigma }_{\mathrm{red}}^b(x,Q^2)$. The Catani-Ciafaloni-Fiorani-Marchesini evolution equation is applied to extend the initial gluon distribution into the whole kinematical region. We have achieved simultaneous description of all considered processes with ${\chi }^2/d.o.f.=2.2$, thus moving forward to the global fit of TMD gluon density from collider data. The obtained TMD gluon distribution in a proton is available for public usage and implemented into the TMDlib package and Monte-Carlo event generator PEGASUS.

    hep-phPRD(2023)·24 citations
21. 21*

    The Low-Scale Seesaw Solution to the $M_W$ and $(g-2{)}_{\mu }$ Anomalies

    Arturo de Giorgi🇪🇸 · Luca Merlo🇪🇸 · Stefan Pokorski🇵🇱

    The recent CDF-II measurement of the $W$-boson mass shows a strong tension with the corresponding Standard Model prediction. Once active neutrino masses are explained in the context of the Low-Scale Seesaw mechanisms, this tension can be resolved. We investigate the possibility of explaining the longstanding muon anomalous magnetic moment anomaly within the same frameworks. We present a simplified extension of the Standard Model, accounting only for the second lepton generation, that describes a massive active neutrino and provides a combined solution to these anomalies. The model is renormalisable and introduces in the spectrum, beyond the sterile species of the Low-Scale Seesaw mechanism, only one pair of exotic vector-like leptons, doublets under the electroweak symmetry. We moreover discuss the extension of this model to the realistic three-family case.

    hep-phFortsch.Phys.(2023)·20 citations
22. 22*

    Improved hot dark matter bound on the QCD axion

    Alessio Notari🇪🇸 · Fabrizio Rompineve🇨🇭 · Giovanni Villadoro🇮🇹

    We strengthen the cosmological bound on the axion mass, by solving the momentum-dependent Boltzmann equations for axion-pion scatterings and by using a phenomenological production rate derived from pion-pion scattering data, overcoming the breakdown of chiral perturbation theory. Using present cosmological datasets we obtain $m_a\le 0.24\text{eV}$. To further improve the bound and exploit the reach of upcoming cosmological surveys, reliable non-perturbative calculations above the QCD crossover are needed.

    hep-phastro-ph.COPRL(2023)·82 citations
23. 23*

    A Precision Relation between $\Gamma (K\to {\mu }^{+}{\mu }^{-})(t)$ and $\mathcal{B}(K_L\to {\mu }^{+}{\mu }^{-})/\mathcal{B}(K_L\to \gamma \gamma )$

    Avital Dery🇺🇸 · Mitrajyoti Ghosh🇺🇸 · Yuval Grossman🇺🇸 · Teppei Kitahara🇯🇵 · Stefan Schacht🇬🇧

    We find that the phase appearing in the unitarity relation between $\mathcal{B}(K_L\to {\mu }^{+}{\mu }^{-})$ and $\mathcal{B}(K_L\to \gamma \gamma )$ is equal to the phase shift in the interference term of the time-dependent $K\to {\mu }^{+}{\mu }^{-}$ decay. A probe of this relation at future kaon facilities constitutes a Standard Model test with a theory precision of about $2\%$. The phase has further importance for sensitivity studies regarding the measurement of the time-dependent $K\to {\mu }^{+}{\mu }^{-}$ decay rate to extract the CKM matrix element combination $|V_{ts}{V}_{td}\sin (\beta +{\beta }_s)|\approx A^2{\lambda }^5\bar{\eta }$. We find a model-independent theoretically clean prediction, ${\cos }^2{\phi }_0=0.96\pm 0.03$. The quoted error is a combination of the theoretical and experimental errors, and both of them are expected to shrink in the future. Using input from the large-$N_C$ limit within chiral perturbation theory, we find a theory preference towards solutions with negative $\cos {\phi }_0$, reducing a four-fold ambiguity in the angle ${\phi }_0$ to a two-fold one.

    hep-phJHEP(2023)·18 citations
24. 24*

    Lepton-Flavoured Scalar Dark Matter in Dark Minimal Flavour Violation

    Harun Acaroğlu🇩🇪 · Prateek Agrawal🇬🇧 · Monika Blanke🇩🇪

    We study a simplified model of lepton-flavoured complex scalar dark matter set up in the Dark Minimal Flavour Violation framework. In this model the Standard Model is extended by a scalar dark matter flavour triplet and a charged fermionic mediator, through which dark matter couples to the right-handed charged leptons of the Standard Model. This interaction is parameterized by a new $3\times 3$ coupling matrix $\lambda$. Consistent with the field content of the model, also the Standard Model's approximate flavour symmetry is extended to include an additional global $U(3)$ associated with the dark matter flavour triplet. In addition to the Standard Model Yukawa couplings, the new coupling matrix $\lambda$ is assumed to constitute the only source that violates this extended symmetry. We analyse the parameter space of this model by investigating constraints from collider searches, lepton flavour violating decays, the observed dark matter relic density, and direct as well as indirect dark matter detection experiments. By performing a combined analysis of all constraints we find that restrictions from lepton flavour violating decays, the observed relic density and dark matter nucleon scattering are dominant. The combination of the latter two renders limits from collider searches irrelevant while indirect detection constraints are weak due to a $p$-wave suppression of the annihilation rate. We conclude that lepton-flavoured scalar dark matter has a rich phenomenology and is a viable dark matter candidate.

    hep-phJHEP(2023)·17 citations
25. 25*

    Minimal length corrections to magnetic birefringence in vacuum

    Ribhu Paul🇮🇳

    We consider the modification to Kruglov's non-linear electrodynamics in the presence of minimal length ($l_p$), by considering a specific formulation of generalized uncertainty principle (GUP). The presence of minimal length has been motivated by several candidate theories of quantum-gravity (both perturbative and non-perturbative). We show that, such minimal length modifications could lead to momentum dependent bounds on zero-point electric field strength, for the aforementioned non-linear model of electrodynamics. We further show that, the existence of minimal length modifies the measure of vacuum birefringence $\Delta n$ in a constant and uniformly strong, external magnetic field. We therefore suggest, the presence of a frictional mechanism of fundamental origin, acting in the parallel direction of polarization of photons (in the presence of strong magnetic field), as an additional effect of quantized background.

    ↳ gr-qchep-phhep-thEur.Phys.J.Plus(2023)·0 citations
26. 26*

    Boost invariant spin hydrodynamics within the first order in derivative expansion

    Rajesh Biswas🇮🇳 · Asaad Daher🇵🇱 · Arpan Das🇵🇱 · Wojciech Florkowski🇵🇱 · Radoslaw Ryblewski🇵🇱

    Boost-invariant equations of spin hydrodynamics confined to the first-order terms in gradients are numerically solved. The spin equation of state, relating the spin density tensor to the spin chemical potential, is consistently included in the first order. Depending on its form and the structure of the spin transport coefficients, we find solutions which are both stable and unstable within the considered evolution times of 10 fm/c. These findings are complementary to the recent identification of stable and unstable modes for perturbed uniform spin systems described by similar hydrodynamic frameworks.

    ↳ nucl-thhep-phPRD(2023)·27 citations
27. 27*

    Tilted non-spatially-flat inflation

    Bharat Ratra🇺🇸

    We construct non-linear inflaton potential energy densities that describe not-necessarily very-slowly-rolling closed and open inflation models, and compute tilted primordial spatial inhomogeneity power spectra that follow from quantum mechanical fluctuations during inflation in these models. Earlier non-flat inflation model power spectra computations assumed an inflaton potential energy density with a linear slope that resulted in very-slow-roll during inflation and untilted power spectra. These new tilted power spectra differ from those that have previously been used to study cosmological data in non-flat cosmological models.

    ↳ astro-ph.COgr-qchep-phhep-thPRD(2022)·10 citations
28. 28*

    Geometric confinement in gauge theories

    Alexander D. Popov🇩🇪

    In 1978, Friedberg and Lee introduced the phenomenological soliton bag model of hadrons, generalizing the MIT bag model developed in 1974 shortly after the formulation of QCD. In this model, quarks and gluons are confined due to coupling with a real scalar field $\rho$ which tends to zero outside some compact region $S\subset {\mathbb{R}}^3$ determined dynamically from the equations of motion. The gauge coupling in the soliton bag model is running as the inverse power of $\rho$ already at the semiclassical level. We show that this model arises naturally as a consequence of introducing the warped product metric $\mathrm{d}{s}_M^2+{\rho }^2\mathrm{d}{s}_G^2$ on the principal $G$-bundle $P(M,G)\cong M\times G$ with a non-Abelian group $G$ over Minkowski space $M={\mathbb{R}}^{3,1}$. Confinement of quarks and gluons in a compact domain $S\subset {\mathbb{R}}^3$ is a consequence of the collapse of the bundle manifold $M\times G$ to $M$ outside $S$ due to shrinking of the group manifold $G$ to a point. We describe the formation of such regions $S$ as a dynamical process controlled by the order parameter field $\rho$.

    ↳ hep-thhep-lathep-phnucl-thSymmetry(2023)·1 citation
29. 29*

    Nested sampling statistical errors

    Andrew Fowlie🇨🇳 · Qiao Li🇨🇳 · Huifang Lv🇨🇳 · Yecheng Sun🇨🇳 · Jia Zhang🇨🇳 · Le Zheng

    Nested sampling (NS) is a popular algorithm for Bayesian computation. We investigate statistical errors in NS both analytically and numerically. We show two analytic results. First, we show that the leading terms in Skilling's expression using information theory match the leading terms in Keeton's expression from an analysis of moments. This approximate agreement was previously only known numerically and was somewhat mysterious. Second, we show that the uncertainty in single NS runs approximately equals the standard deviation in repeated NS runs. Whilst intuitive, this was previously taken for granted. We close by investigating our results and their assumptions in several numerical examples, including cases in which NS uncertainties increase without bound.

    ↳ astro-ph.IMhep-phphysics.data-anstat.COMNRAS(2023)·1 citation
30. 30*

    Testing $\Lambda$CDM with eBOSS data using a model independent diagnostic

    Arman Shafieloo🇰🇷 · Sangwoo Park · Varun Sahni🇮🇳 · Alexei A. Starobinsky🇷🇺

    The $Om3$ diagnostic (Shafieloo et al. 2012) tests the consistency of the cosmological constant as a candidate for dark energy using Baryon Acoustic Oscillation (BAO) data. An important feature of $Om3$ is that it is independent of any parametric assumption for dark energy, neither does it depend upon the dynamics of the Universe during the pre-recombination nor post-recombination eras. In other words, $Om3$ can be estimated using BAO observables and used either to confirm or falsify the cosmological constant independently of the value of the Hubble constant $H_0$ (expansion rate at $z=0$), and the comoving sound horizon at the baryon drag epoch, $r_d$ (which is a function of the physics of the Universe prior to recombination). Consequently, $Om3$ can play a key role in identifying the nature of dark energy (DE) regardless of the existing tensions in the standard model of cosmology and the possible presence of systematics in some of the data sets. We revisit $Om3$ using the most recent BAO observables from the eBOSS survey in order to test the consistency of the cosmological constant with this data. Our results show the consistency of dark energy being the cosmological constant. Moreover, with eBOSS data, we have achieved a precision of $1.5\%$ for this three-point diagnostic. This demonstrates that $Om3$ can be a potent diagnostic of dark energy when used in conjunction with the high precision data expected from forthcoming large scale structure surveys such as the Dark Energy Spectroscopic Instrument (DESI) and Euclid.

    ↳ astro-ph.COhep-phPRD(2023)·2 citations
31. 31*

    Constraints on axionlike particles from a combined analysis of three flaring $\text{Fermi}$ flat-spectrum radio quasars

    James Davies🇬🇧 · Manuel Meyer🇩🇪 · Garret Cotter🇬🇧

    Many theories beyond the Standard Model of particle physics predict the existence of axionlike particles (ALPs) that mix with photons in the presence of a magnetic field. Searching for the effects of ALP-photon mixing in gamma-ray observations of blazars has provided some of the strongest constraints on ALP parameter space so far. Previously, only individual sources have been analysed. We perform a combined analysis on $\text{Fermi}$ Large Area Telescope data of three bright, flaring flat-spectrum radio quasars, with the blazar jets themselves as the dominant mixing region. For the first time, we include a full treatment of photon-photon dispersion within the jet, and account for the uncertainty in our B-field model by leaving the field strength free in the fitting. Overall, we find no evidence for ALPs, but are able to exclude the ALP parameters $m_a\lesssim 200$ neV and $g_{a\gamma }\gtrsim 5\times 10^{-12}$ GeV${}^{-1}$ with 95\% confidence.

    ↳ astro-ph.HEhep-phPRD(2023)·41 citations
32. 32*

    Primordial black holes and induced gravitational waves from double-pole inflation

    Chengjie Fu🇨🇳 · Shao-Jiang Wang🇨🇳

    The primordial black hole (PBH) productions from the inflationary potential with an inflection point usually rely heavily on the fine-tuning of the model parameters. We propose in this work a new kind of the $\alpha$-attractor inflation with asymmetric double poles that naturally and easily lead to a period of non-attractor inflation, during which the PBH productions are guaranteed with less fine-tuning the model parameters. This double-pole inflation can be tested against the observational data in the future with rich phenomenological signatures: (1) the enhanced curvature perturbations at small scales admit a distinctive feature of ultraviolet oscillations in the power spectrum; (2) the quasi-monochromatic mass function of the produced PBHs can be made compatible to the asteroid-mass PBHs as the dominant dark matter component, the planet-mass PBHs as the OGLE ultrashort-timescale microlensing events, and the solar-mass PBHs as the LIGO-Virgo events; (3) the induced gravitational waves can be detected by the gravitational-wave detectors in space and Pulsar Timing Array/Square Kilometer Array.

    ↳ astro-ph.COgr-qchep-phJCAP(2023)·32 citations
33. 33*

    Rational Tracer: a Tool for Faster Rational Function Reconstruction

    Vitaly Magerya🇩🇪

    Rational Tracer (Ratracer) is a tool to simplify complicated arithmetic expressions using modular arithmetics and rational function reconstruction, with the main idea of separating the construction of expressions (via tracing, i.e. recording the list of operations) and their subsequent evaluation during rational reconstruction. Ratracer can simplify arithmetic expressions (provided as text files), solutions of linear equation systems (specifically targeting Integration-by-Parts (IBP) relations between Feynman integrals), and even more generally: arbitrary sequences of rational operations, defined in C++ using the provided library ratracer.h. Any of these can also be automatically expanded into series prior to reconstruction. This paper describes the usage of Ratracer specifically focusing on IBP reduction, and demonstrates its performance benefits by comparing with Kira+FireFly and Fire6. Specifically, Ratracer achieves a typical ~10x probe time and ~5x overall time speedup over Kira+FireFly, and even higher if only a few terms in $\epsilon$ need to be reconstructed.

    ↳ physics.data-anhep-ph43 citations
34. 34*

    Primordial Black Holes having Gravitomagnetic Monopole

    Chandrachur Chakraborty (MCNS-MAHE, India)🇮🇳 · Sudip Bhattacharyya (TIFR, India)🇮🇳

    A primordial black hole (PBH) is thought to be made of the regular matter or ordinary mass ($M$) only, and hence could have already been decayed due to the Hawking radiation if its initial ordinary mass were $\lesssim 5\times 10^{11}$ kg. Here, we study the role of gravitomagnetic monopole for the evaporation of PBHs, and propose that the lower energy PBHs (equivalent to ordinary mass $M<<5\times 10^{11}$ kg) could still exist in our present Universe, if it has gravitomagnetic monopole. If a PBH was initially made of both regular matter and gravitomagnetic monopole, the regular matter could decay away due to the Hawking radiation. The remnant gravitomagnetic monopole might not entirely decay, which could still be found as a PBH in the form of the pseudo `mass-energy'. If a PBH with $M\gtrsim 5\times 10^{11}$ kg is detected, one may not be able to conclude if it has gravitomagnetic monopole. But, a plausible detection of a relatively low energy (equivalent to $2.176\times 10^{-8}$ kg $<M\lesssim 5\times 10^{11}$ kg) PBH in future may imply the existence of a gravitomagnetic monopole PBH, which may or may not contain the ordinary mass.

    ↳ astro-ph.HEastro-ph.COgr-qchep-phPRD(2022)·16 citations
35. 35*

    Spin 1/2 from Gluons

    A. P. Balachandran🇺🇸

    The theta vacuum in QCD is the standard vacuum, twisted by the exponential of the Chern-Simons term. But what is the quantum operator $U(g)$ for winding number $1$? We construct $U(g)$ in this note. The Poincare' rotation generators commute with it only if they are augmented by the spin 1/2 representation of the Lorentz group coming from large gauge transformations. This result is analogous to the 'spin-isopin' mixing result due to Jackiw and Rebbi [1], and Hasenfratz and 't Hooft[2] and a similar result in fuzzy physics [3]. Hence states can drastically affect representations of observables. This fact is further shown by charged states dressed by infrared clouds. Following Mund, Rehren and Schroer [4], we find that Lorentz invariance is spontaneously broken in these sectors. This result has been extended earlier to QCD (references [15] given in the Final Remarks) where even the global QCD group is shown to be broken. It is argued that the escort fields of [4] are the Higgs fields for Lorentz and colour breaking. They are string-localised fields where the strings live in a union of de Sitter spaces. Their oscillations and those of the infrared clouds generate the associated Goldstone modes.

    ↳ hep-thgr-qchep-phMod.Phys.Lett.A(2023)·2 citations
36. 36*

    Scale setting and the light baryon spectrum in $N_f=2+1$ QCD with Wilson fermions

    Gunnar S. Bali🇩🇪 · Sara Collins🇩🇪 · Peter Georg🇩🇪 · Daniel Jenkins🇩🇪 · Piotr Korcyl🇵🇱 · Andreas Schäfer🇩🇪 · Enno E. Scholz🇩🇪 · Jakob Simeth🇩🇪 · Wolfgang Söldner🇩🇪 · Simon Weishäupl🇩🇪

    We determine the light baryon spectrum on ensembles generated by the Coordinated Lattice Simulations (CLS) effort, employing $N_f=2+1$ flavours of non-perturbatively improved Wilson fermions. The hadron masses are interpolated and extrapolated within the quark mass plane, utilizing three distinct trajectories, two of which intersect close to the physical quark mass point and the third one approaching the SU(3) chiral limit. The results are extrapolated to the continuum limit, utilizing six different lattice spacings ranging from $a\approx 0.10$fm down to below $0.04$fm. The light pion mass varies from $M_{\pi }\approx 429$MeV down to $127$MeV. In general, the spatial extent is kept larger than four times the inverse pion mass and larger than $2.3$fm, with additional small and large volume ensembles to investigate finite size effects. We determine the Wilson flow scales $\sqrt{t_{0,\mathrm{ph}}}=0.1449_{(9)}^{(7)}$fm and $t_0^{\ast }\approx t_{0,\mathrm{ph}}$ from the octet cascade ($\Xi$ baryon). Determining the light baryon spectrum in the continuum limit, we find the nucleon mass $m_N=941.7_{(7.6)}^{(6.5)}$MeV and the other stable baryon masses to agree with their experimental values within sub-percent level uncertainties. Moreover, we determine SU(3) and SU(2) chiral perturbation theory low energy constants, including the octet and the $\Omega$ baryon sigma~terms ${\sigma }_{\pi N}=43.9(4.7)$MeV, ${\sigma }_{\pi \Lambda }=28.2_{(5.4)}^{(4.3)}$MeV, ${\sigma }_{\pi \Sigma }=25.9_{(6.1)}^{(3.8)}$MeV, ${\sigma }_{\pi \Xi }=11.2_{(6.4)}^{(4.5)}$MeV and ${\sigma }_{\pi \Omega }=6.9_{(4.3)}^{(5.3)}$MeV, as well as various parameters, renormalization factors and improvement coefficients that are relevant for simulations with our lattice action.

    ↳ hep-lathep-phJHEP(2023)·90 citations
37. 37*

    Two-neutrino $\beta \beta$ decay of ${}^{136}$Xe to the first excited $0^{+}$ state in ${}^{136}$Ba

    Lotta Jokiniemi🇨🇦 · Beatriz Romeo🇪🇸 · Catharina Brase🇩🇪 · Jenni Kotila🇫🇮 · Pablo Soriano🇪🇸 · Achim Schwenk🇩🇪 · Javier Menéndez🇪🇸

    We calculate the nuclear matrix element for the two-neutrino $\beta \beta$ decay of ${}^{136}$Xe into the first excited $0^{+}$ state of ${}^{136}$Ba. We use different many-body methods: the quasiparticle random-phase approximation (QRPA) framework, the nuclear shell model, the interacting boson model (IBM-2), and an effective field theory (EFT) for $\beta$ and $\beta \beta$ decays. While the QRPA suggests a decay rate at the edge of current experimental limits, the shell model points to a half-life about two orders of magnitude longer. The predictions of the IBM-2 and the EFT lie in between, and the latter provides systematic uncertainties at leading order. An analysis of the running sum of the nuclear matrix element indicates that subtle cancellations between the contributions of intermediate states can explain the different theoretical predictions. For the EFT, we also present results for two-neutrino $\beta \beta$ decays to the first excited $0^{+}$ state in other nuclei.

    ↳ nucl-thhep-exhep-phnucl-exPLB(2023)·15 citations
38. 38*

    Photon Ring Astrometry for Superradiant Clouds

    Yifan Chen🇩🇰 · Xiao Xue🇩🇪 · Richard Brito🇵🇹 · Vitor Cardoso🇩🇰

    Gravitational atoms produced from the superradiant extraction of rotational energy of spinning black holes can reach energy densities significantly higher than that of dark matter, turning black holes into powerful potential detectors for ultralight bosons. These structures are formed by coherently oscillating bosons, which induce oscillating metric perturbations deflecting photon geodesics passing through their interior. The deviation of nearby geodesics can be further amplified near critical bound photon orbits. We discuss the prospect of detecting this deflection using photon ring autocorrelations with the Event Horizon Telescope and its next-generation upgrade, which can probe a large unexplored region of the cloud mass parameter space when compared with previous constraints.

    ↳ gr-qcastro-ph.COastro-ph.HEhep-phPRL(2023)·53 citations
39. 39*

    Kinematic signatures of impulsive supernova feedback in dwarf galaxies

    Jan D. Burger🇺🇸 · Jesús Zavala🇮🇸 · Laura V. Sales🇺🇸 · Mark Vogelsberger🇺🇸 · Federico Marinacci🇮🇹 · Paul Torrey🇺🇸

    Impulsive supernova feedback and non-standard dark matter models, such as self-interacting dark matter (SIDM), are the two main contenders for the role of the dominant core formation mechanism at the dwarf galaxy scale. Here we show that the impulsive supernova cycles that follow episodes of bursty star formation leave distinct features in the distribution function of stars: groups of stars with similar ages and metallicities develop overdense shells in phase space. If cores are formed through supernova feedback, we predict the presence of such features in star-forming dwarf galaxies with cored host halos. Their systematic absence would favor alternative dark matter models, such as SIDM, as the dominant core formation mechanism.

    ↳ astro-ph.GAhep-phPRL(2022)·5 citations
40. 40*

    Quantum-probabilistic Hamiltonian learning for generative modelling & anomaly detection

    Jack Y. Araz🇬🇧 · Michael Spannowsky🇬🇧

    The Hamiltonian of an isolated quantum mechanical system determines its dynamics and physical behaviour. This study investigates the possibility of learning and utilising a system's Hamiltonian and its variational thermal state estimation for data analysis techniques. For this purpose, we employ the method of Quantum Hamiltonian-based models for the generative modelling of simulated Large Hadron Collider data and demonstrate the representability of such data as a mixed state. In a further step, we use the learned Hamiltonian for anomaly detection, showing that different sample types can form distinct dynamical behaviours once treated as a quantum many-body system. We exploit these characteristics to quantify the difference between sample types. Our findings show that the methodologies designed for field theory computations can be utilised in machine learning applications to employ theoretical approaches in data analysis techniques.

    ↳ quant-phcs.LGhep-exhep-ph+1PRA(2023)·27 citations
41. 41*

    {\gamma}-Ray and ultra-high energy neutrino background suppression due to solar radiation

    Shyam Balaji🇫🇷

    The Sun emits copious amounts of photons and neutrinos in an approximately spatially isotropic distribution. Diffuse $\gamma$-rays and ultra-high energy (UHE) neutrinos from extragalactic sources may subsequently interact and annihilate with the emitted solar photons and neutrinos respectively. This will in turn induce an anisotropy in the cosmic ray (CR) background due to attenuation of the $\gamma$-ray and UHE neutrino flux by the solar radiation. Measuring this reduction, therefore, presents a simple and powerful astrophysical probe of electroweak interactions. In this letter we compute such anisotropies for TeV $\gamma$-rays, which at the Earth (Sun) can be at least $\simeq 10^{-4},(10^{-2})$. The optical depth at Earth for elongation angles more focused around the Sun ($\lesssim 10^{\circ }$), can be around $10^{-3}$ and larger. Neutrino attenuation is extremely tiny for for PeV scale UHE neutrinos. We briefly discuss observational prospects for experiments such as the Fermi Gamma-Ray Space Telescope Large Area Telescope (Fermi LAT), High-Altitude Water Cherenkov (HAWC) detector, The Large High Altitude Air Shower Observatory (LHAASO), Cherenkov Telescope Array (CTA) and IceCube. The potential for measuring $\gamma$-ray attenuation at orbital locations of other active satellites such as the Parker Solar Probe and James Webb Space Telescope (JWST) is also explored.

    ↳ astro-ph.HEastro-ph.SRhep-phPLB(2023)·6 citations
42. 42*

    Bootstrapping One-Loop Inflation Correlators with the Spectral Decomposition

    Zhong-Zhi Xianyu🇨🇳 · Hongyu Zhang🇨🇳

    Phenomenological studies of cosmological collider physics in recent years have identified many 1-loop inflation correlators as leading channels for discovering heavy new particles around or above the inflation scale. However, complete analytical results for these massive 1-loop correlators are currently unavailable. In this work, we embark on a program of bootstrapping inflation correlators with massive exchanges at 1-loop order, with the input of tree-level inflation correlators and the techniques of spectral decomposition in dS. As a first step, we present for the first time the complete and analytical results for a class of 4-point and 3-point inflation correlators mediated by massive scalar fields at the 1-loop order. Using the full result, we provide simple and reliable analytical approximations for the signals and the background in the squeezed limit. We also identify configurations of the scalar trispectrum where the oscillatory signal from the loop is dominant over the background.

    ↳ hep-thastro-ph.COhep-phJHEP(2023)·77 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.