Thu·Dec 1, 2022Thursday·December 1, 2022

1. 01*

   Evaluation of three-loop self-energy master integrals with four or five propagators

   Stephen P. Martin🇺🇸

   I obtain identities satisfied by the 3-loop self-energy master integrals with four or five propagators with generic masses, including the derivatives with respect to each of the squared masses and the external momentum invariant. These identities are then recast in terms of the corresponding renormalized master integrals, enabling straightforward numerical evaluation of them by the differential equations approach. Some benchmark examples are provided. The method used to obtain the derivative identities relies only on the general form implied by integration by parts relations, without actually following the usual integration by parts reduction procedure. As a byproduct, I find a simple formula giving the expansion of the master integrals to arbitrary order in the external momentum invariant, in terms of known derivatives of the corresponding vacuum integrals.

   hep-phPRD(2023)·3 citations
2. 02*

   Limiting multiple hyperchargeless scalar triplets using electroweak phase transition and other constraints

   Nabarun Chakrabarty🇮🇳

   While an additional scalar multiplet over and above the Standard Model can lead to a strong electroweak phase transition, depending on its quantum numbers, it also potentially confronts crucial constraints from theory and experiments. Should there exist more than one copy of such a multiplet, it is possible to predict that number from the requirements of a strong electroweak phase transition and agreement with the latest constraints. We aim to probe this specific issue in this study in the context of $N$ degenerate scalar triplets governed by a global O$(N)$ symmetry. We fold in important constraints from $h\to \gamma \gamma$ signal strength, dark matter direct detection and Landau pole behaviour. A combined analysis reveals $N\gtrsim 70$ for a strong phase transition and consistency with the constraints. We also look into possible gravitational wave signals in the parameter regions of interest.

   hep-ph0 citations
3. 03*

   Hadronic light-by-light contribution to the muon $g-2$ from holographic QCD with solved $U(1{)}_A$ problem

   Josef Leutgeb🇦🇹 · Jonas Mager🇦🇹 · Anton Rebhan🇦🇹

   We employ the comparatively minimal extension of hard-wall AdS/QCD due to Katz and Schwartz which takes into account the U(1)${}_A$ anomaly for computing hadronic light-by-light scattering contributions of pseudoscalar and axial vector mesons to the anomalous magnetic moment of the muon $a_{\mu }$. By including a gluon condensate as one extra tunable parameter besides those fixed by $f_{\pi }$ and the pion, kaon, and rho masses, we obtain remarkably accurate fits for $\eta$ and ${\eta }^{\prime }$ masses and their decay rates to photons, leading to $a_{\mu }$ contributions in complete agreement with the Standard Model result by the Muon $g-2$ Theory Initiative. Turning to the less well understood axial vector contributions, we update our previous predictions obtained in flavor-symmetric hard-wall AdS/QCD models without U(1)${}_A$ breaking.

   hep-phPRD(2023)·72 citations
4. 04*

   Strong two-meson decays of light and charmed vector mesons

   Roberto Correa da Silveira🇧🇷 · Fernando E. Serna🇧🇷 · Bruno El-Bennich🇧🇷

   We calculate the strong decay couplings for $\rho \to \pi \pi$, $\varphi \to KK$, $K^{\ast }\to K\pi$ and $D^{\ast }\to D\pi$ in a unified and consistent approach based on the impulse approximation, nonperturbative solutions of the quark-gap equation and the Poincaré invariant Bethe-Salpeter amplitudes of vector and pseudoscalar mesons. In particular, we obtain the coupling $g_{D^{\ast }D\pi }=17.24_{-2.30}^{+3.06}$ in very good agreement with the experimental value by CLEO, which corresponds to a strong effective coupling between heavy vector and pseudoscalar mesons to the pion of $\hat{g}=0.58_{-0.08}^{+0.10}$.

   hep-phhep-exhep-latnucl-thPRD(2023)·13 citations
5. 05*

   Unitarity bounds on extensions of Higgs sector

   Bo-Qiang Lu🇨🇳 · Da Huang🇨🇳

   It is widely believed that extensions of the minimal Higgs sector is one of the promising directions for resolving many puzzles beyond the Standard Model (SM). In this work, we study the unitarity bounds on the models by extending the two-Higgs-doublet model with an additional real or complex Higgs triplet scalar. By noting that the SM gauge symmetries $SU(2{)}_L\times U(1{)}_Y$ are recovered at high energies, we can classify the two-body scattering states by decomposing the direct product of two scalar multiplets into their direct sum of irreducible representations of electroweak gauge groups. In such state bases, the s-wave amplitudes of two-body scalar scatterings can be written in the form of block-diagonalized scattering matrices. Then the application of the perturbative unitarity conditions on the eigenvalues of scattering matrices leads to the analytic constraints on the model parameters. Finally, we numerically investigate the complex triplet scalar extension of the two-Higgs-doublet model, finding that the perturbative unitarity places useful stringent bounds on the model parameter space.

   hep-phJHEP(2023)·3 citations
6. 06*

   The photon production and collective flows from magnetic induced gluon fusion and splitting in early stage of high energy nuclear collision

   Moran Jia🇨🇳 · Huixia Li🇨🇳 · Defu Hou🇨🇳

   We present an event-by-event study of photon production in early stage of high energy nuclear collisions, where the system is dominant by highly occupied of gluons and initialized by McLerran-Venugopalan model. The photons are produced through the gluon fusion and splitting processes when strong magnetic field is included. We study the spectra and collective flows of the photons and show their dependence on transverse momentum $q_T$. It is found that in our approach the photons from boost invariant evolving glasma provide visible enhancement on spectrum and obvious contribution on $v_2$ of the total direct photons. The results, by weighting on top of parton-hadron-string dynamics (PHSD) model, agree even better with experiment measurements in Au-Au 20\%-40\% centrality collisions at $\sqrt{s_{NN}}=200$GeV.

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

   Probing New Physics in the Vector-like Lepton Model by Lepton Electric Dipole Moments

   Koichi Hamaguchi🇯🇵 · Natsumi Nagata🇯🇵 · Genta Osaki🇯🇵 · Shih-Yen Tseng🇯🇵

   We examine the lepton dipole moments in an extension of the Standard Model (SM), which contains vector-like leptons that couple only to the second-generation SM leptons. The model naturally leads to sizable contributions to the muon $g-2$ and the muon electric dipole moment (EDM). One feature of this model is that a sizable electron EDM is also induced at the two-loop level due to the existence of new vector-like leptons in the loops. We find parameter regions that can explain the muon $g-2$ anomaly and are also consistent with the experimental constraints coming from the electron EDM and the Higgs decay $h\to {\mu }^{+}{\mu }^{-}$. The generated EDMs can be as large as $O(10^{-22})e\cdot \mathrm{cm}$ for the muon and $O(10^{-30})e\cdot \mathrm{cm}$ for the electron, respectively, which can be probed in future experiments for the EDM measurements.

   hep-phJHEP(2023)·15 citations
8. 08*

   Scattering versus Forbidden Decay in Dark Matter Freeze-in

   Shao-Ping Li🇨🇳

   It is generically believed that the two-body scattering is suppressed by higher-order weak couplings with respect to the two-body decay. We show that this does not always hold when a heavy particle is produced by forbidden decay in a thermal plasma, where the scattering shares the same order of couplings with the decay. We find that there is a simple and close relation between the forbidden decay and the same-order scattering. To illustrate this point, we consider freeze-in production of heavy dark matter via a light scalar mediator. We point out that, when the Boltzmann (quantum) statistics is used, the forbidden decay can contribute to the dark matter relic density at 5$\%$-24$\%$ (10$\%$-$39\%$) with a weak thermal coupling, while the contribution from the scattering channel can be several orders of magnitude larger than from the forbidden decay if the thermal coupling is much smaller. Such a relative effect between the scattering and the forbidden decay could also exist in other plasma-induced processes, such as the purely thermal generation of the right-handed neutrino dark matter, or of the lepton asymmetry in leptogenesis.

   hep-phPRD(2023)·3 citations
9. 09*

   High-energy signals from heavy-flavor physics

   Andrèe Dafne Bolognino🇮🇹 · Francesco Giovanni Celiberto🇮🇹 · Michael Fucilla🇮🇹 · Dmitry Yu. Ivanov🇷🇺 · Mohammed M.A. Mohammed🇮🇹 · Alessandro Papa🇮🇹

   Working in the hybrid high-energy/collinear factorization, where the next-to-leading resummation of energy logarithms is combined with collinear parton densities and fragmentation functions, we study observables sensitive to high-energy dynamics in the context of heavy-flavor physics.

   hep-phActa Phys.Polon.Supp.(2023)·16 citations
10. 10*

    Holographic Study of the $Q\bar{Q}$ Chaotic Dynamics in General Thermal Background

    N. Losacco🇮🇹

    The holographic approach is applied to study the chaotic behaviour of a strongly coupled $Q\bar{Q}$ pair in general thermal background. We consider two different backgrounds, one with finite temperature and baryon density, and one with finite temperature and constant magnetic field along a fixed direction. The results allow us to understand the dependence of the chaotic dynamics on the background, to test the universal bound on chaos conjectured by Maldacena, Shenker and Standford (MSS)

    hep-phEPJ Web Conf.(2022)·1 citation
11. 11*

    Contribution of the Weinberg-type operator to atomic electric dipole moments

    Naohiro Osamura🇯🇵

    We report the calculation of the isovector CP-odd $\pi N$ interaction generated by the Weinberg operator, the CP violating three-gluon operator. This enables to restrict models which induce the operator by using experimental data of atomic electric dipole moment. The QCD sum rules are used to determine the matrix element required to assess the CP-odd $\pi N$ interactions. The relation between the Weinberg operator and the Hg and Xe EDMs is clarified, and the constraint on the Weinberg operator is obtained using the experimental data for the Hg EDM.

    hep-phnucl-thphysics.atom-phAIP Conf.Proc.(2024)·0 citations
12. 12*

    Disentangling longitudinal and transverse modes of the $\varphi$ meson through dilepton and kaon decays

    In Woo Park🇰🇷 · Hiroyuki Sako🇯🇵 · Kazuya Aoki🇯🇵 · Philipp Gubler🇯🇵 · Su Houng Lee🇰🇷

    Angular distributions of $\varphi$ meson decay amplitudes of $e^{+}{e}^{-}$ and $K^{+}{K}^{-}$ channels are computed using both specific interaction Lagrangians and simple arguments relying on angular momentum conservation. Based on the obtained results, we assess methods to experimentally disentangle the longitudinal and transverse polarization modes of the $\varphi$ meson and discuss advantages and disadvantages of employing either the leptonic or hadronic decay modes for this task.

    hep-phPRD(2023)·26 citations
13. 13*

    SuSpect3: A C++ Code for the Supersymmetric and Higgs Particle Spectrum of the MSSM

    Jean-Loic Kneur🇫🇷 · Gilbert Moultaka🇫🇷 · Michael Ughetto🇫🇷 · Dirk Zerwas🇫🇷 · Abdelhak Djouadi🇪🇸

    We present the program SuSpect3 that calculates the masses and couplings of the Higgs and supersymmetric particles predicted by the Minimal Supersymmetric Standard Model (MSSM). The model is implemented in both its non-constrained version, the MSSM, and its constrained versions, such as the minimal supergravity and the gauge or anomaly mediated supersymmetry breaking models, in which the soft supersymmetry-breaking parameters obey certain universal boundary conditions at the high energy scale. The low energy parameters are then obtained using renormalization group equations and electroweak symmetry breaking, and all the dominant radiative corrections have been consistently implemented. SuSpect3 is a major rewrite, in C++ object oriented programming, of the FORTRAN code SuSpect. It includes all the features of the earlier code in an improved and updated manner, and involves new options such as compressed SUSY scenarios, an MSSM-inflation model and the possibility of using the observed Higgs mass as an input. The main features and the use of the program are explained.

    hep-phComput.Phys.Commun.(2023)·9 citations
14. 14*

    Chiral perturbation theory

    Stefan Scherer🇩🇪 · Matthias R. Schindler🇺🇸

    Chiral perturbation theory (ChPT) is an effective field theory that describes the properties of strongly-interacting systems at energies far below typical hadron masses. The degrees of freedom are hadrons instead of the underlying quarks and gluons. ChPT is a systematic and model-independent approximation method based on an expansion of amplitudes in terms of light-quark masses and momenta. The following is a brief overview of ChPT that is largely based on Scherer, Schindler, Lect. Notes Phys. 830 (2012), which can be referred to for a more detailed introduction.

    hep-phnucl-th2 citations
15. 15*

    Production of the triply heavy ${\Omega }_{ccc}$ and ${\Omega }_{bbb}$ baryons at $e^{+}{e}^{-}$ colliders

    Su-Zhi Wu🇨🇳 · Pei Wu🇨🇳 · You-Wei Li🇨🇳

    Non-relativistic quantum chromodynamics (NRQCD) factorization formulism is an important approach to investigate the production of the heavy quarkonium. In this paper, we study the production of the ${\Omega }_{ccc}$ and ${\Omega }_{bbb}$ at the $e^{+}{e}^{-}$ collider, using the NRQCD factorization formulism. We calculate the total and differential cross sections exactly of the processes, $e^{+}{e}^{-}\to {\gamma }^{\ast }/Z^{\ast }\to {\Omega }_{ccc}\bar{c}\bar{c}\bar{c}$ and $e^{+}{e}^{-}\to {\gamma }^{\ast }/Z^{\ast }\to {\Omega }_{bbb}\bar{b}\bar{b}\bar{b}$, in the leading order at the $e^{+}{e}^{-}$ colliders with different energies. The results show that it is hard to observe them at the $e^{+}{e}^{-}$ collider directly.

    hep-phPhysRevD.107.116022,2023·2 citations
16. 16*

    The ReBB model at 8 TeV: Odderon exchange is not a probability, but a certainty

    I. Szanyi🇭🇺 · T. Csörgő🇭🇺

    The Real Extended Bialas-Bzdak (ReBB) model study is extended to the 8 TeV $pp$ TOTEM elastic differential cross section data. The analysis shows that the ReBB model describes the $pp$ and $p\bar{p}$ differential cross section data in the limited $0.37\le -t\le 1.2$ GeV${}^2$ and $1.96\le \sqrt{s}\le 8$ TeV kinematic region, in a statistically acceptable manner. In this kinematic region a greater than 30 $\sigma$ model-dependent Odderon signal is observed by comparing the $pp$ and ReBB extrapolated $p\bar{p}$ differential cross sections. Thus, in practical terms, within the framework of the ReBB model, Odderon exchange is not a probability, but a certainty.

    hep-phActa Phys.Polon.Supp.(2023)·2 citations
17. 17*

    Vector meson-nucleon scattering length $|{\alpha }_{VN}|$ and trace anomalous energy contribution to the nucleon mass $T_A$

    Chengdong Han🇨🇳 · Wei Kou🇨🇳 · Rong Wang🇨🇳 · Xurong Chen🇨🇳

    Low-energy scattering processes of vector meson and nucleon are an important window for studying non-perturbative QCD. The interaction of vector meson with nucleon, vector meson-nucleon scattering length $|{\alpha }_{VN}|$, is an important component of the study of hadronic interactions. Nowadays many scattering length values $|{\alpha }_{VN}|$ have been reported using the recent photoproduction experiment data or quasi data. In addition, the study of trace anomalous energy contribution to the proton mass is also a hot topic in non-perturbative QCD and hadron physics. However, it is difficult to measure proton trace anomalous energy experimentally, and the study of the trace anomaly of proton is still inconclusive. In this study, we established the relationship between the scattering length of the vector meson-proton $|{\alpha }_{Vp}|$ and the trace anomaly contribution of the proton mass $T_A$. With the scattering length values extracted by using the Vector Meson Dominance model, we obtained the trace anomaly contribution of the proton mass $T_A$ = (22.8$\%$ $\pm$ 1.2$\%$), which is of similar order of magnitude as the 23$\%$ given by Lattice QCD calculation. We conjecture that the trace anomaly contribution of nucleon is independent of the type of vector meson probe. We hope that high precision measurements of vector meson-nucleon scattering length could give us a better chance to explore the origin of the nucleon mass.

    hep-phEPJA(2023)·5 citations
18. 18*

    On the Possibility of Demonstrating Confinement in Non-Supersymmetric Theories by Deforming Confining Supersymmetric Theories

    Michael Dine🇺🇸

    We review arguments that supersymmetric QCD with $N$ colors and $N_f\ge 0$ massive quarks confines. We explain that this remains the case for small soft breakings and small supersymmetric masses for any quarks. These results continue to hold at large $N$. We then consider these theories with large soft breakings -- real QCD -- describing the problem in terms of the direct computation of the linear potential between a heavy quark and antiquark. We provide naive arguments that confinement persists, and then give a more general treatment. The features required for the naive arguments are generally believed to hold at large $N$. Extending them to finite $N$ requires only mild assumptions.

    hep-phhep-th4 citations
19. 19*

    The baryon coupling scheme in an unified SU(3) and SU(6) symmetry formalism

    Luiz L. Lopes🇧🇷 · Kauan D. Marquez🇧🇷 · Débora P. Menezes🇧🇷

    We calculate the baryon-meson coupling constants for the spin-1/2 baryonic octet and spin-3/2 decuplet in a unified approach relying on symmetry arguments such as the fact that the Yukawa couplings, present in the Lagrangian density of the Walecka-type models, must be an invariant under SU(3) and SU(6) group transformations. The coupling constants of the baryon with the scalar $\sigma$ meson are fixed to reproduce the known potential depths for the hyperons and $\Delta$ resonances, in an approach that can be extended to all particles. We then apply the calculated coupling constants to study neutron star matter with hyperons and deltas admixed to its composition. We conclude that the ${\Delta }^{-}$ is by far the most important exotic particle that can be present in the neutron star interior. It is always present, independent of the chosen parameterization, and might appear in almost every known neutron star, once its onset happens at very low density. Yet, its presence affects the astrophysical properties of the canonical 1.4 M${}_{\odot }$ star, and, in some cases, it can even contribute to an increase in the maximum mass reached.

    hep-phastro-ph.HEnucl-thPRD(2023)·33 citations
20. 20*

    KKMChh: matching CEEX photonic ISR to a QED-corrected parton shower

    S. A. Yost🇺🇸 · S. Jadach🇵🇱 · B. F. L. Ward🇺🇸 · Z. Wąs🇵🇱

    KKMChh adapts the CEEX (Coherent Exclusive Exponentiation) formalism of the Monte Carlo Program KKMC for Z boson production and decay to hadron scattering. Amplitude-level soft photon exponentiation of initial and final state radiation, together with initial-final interference, is matched to a perturbative calculation to second order next-to-leading logarithm, and electroweak corrections to the hard process are included via DIZET. The first release of KKMChh included complete initial state radiation calculated with current quark masses. This version assumes idealized pure-QCD PDFs with negligible QED contamination. Traditional PDFs neglect QED evolution but are not necessarily free of QED influence in the data. QED-corrected PDFs provide a firmer starting point for precision QED work. We describe a new procedure for matching KKMChh's initial state radiation to a QED-corrected PDF, and compare this to earlier approaches.

    hep-phPoS·8 citations
21. 21*

    Constraints on the hadronic light-by-light in the Melnikov-Vainshtein regime

    Johan Bijnens🇸🇪 · Nils Hermansson-Truedsson🇨🇭 · Antonio Rodríguez-Sánchez🇮🇹

    The muon anomalous magnetic moment continues to attract attention due to the possible tension between the experimentally measured value and the theoretical Standard Model prediction. With the aim to reduce the uncertainty on the hadronic light-by-light contribution to the magnetic moment, we derive short-distance constraints in the Melnikov-Vainshtein regime which are useful for data-driven determinations. In this kinematical region, two of the four electromagnetic currents are close in the four-point function defining the hadronic light-by-light tensor. To obtain the constraints, we develop a systematic operator product expansion of the tensor in question to next-to-leading order in the expansion in operators. We evaluate the leading in ${\alpha }_s$ contributions and derive constraints for the next-to-leading operators that are also valid nonperturbatively.

    hep-phJHEP(2023)·45 citations
22. 22*

    The Hierarchy Problem and the Top Yukawa: An Alternative to Top Partner Solutions

    Andreas Bally🇩🇪 · Yi Chung🇩🇪 · Florian Goertz🇩🇪

    We discuss the role of the top-quark Yukawa coupling $y_t$ concerning the hierarchy problem and construct an alternative scheme to the conventional solutions with top partners. In traditional models, like SUSY or composite Higgs, top partners cancel the top loop contribution to the Higgs quadratic term. The lack of evidence for such colored partners however drives these models into more and more fine-tuned regions. Here, an alternative means to mitigate the top loop, allowing for natural electroweak symmetry breaking, is presented. Emphasizing that we have not measured the top-Higgs interactions at high scales yet, we envisage scenarios where this interaction is only approaching its sizable strength in the infra-red, but gets strongly suppressed at high scales. We first discuss possible effects via a modification of the running of the top Yukawa coupling. Then, we turn to models where the top Yukawa is generated at one-loop level. Originated from a dimension-six operator, it drops when crossing the mass threshold of new degrees of freedom. In either case, the top partners are replaced by some new top-philic particles with strong interaction. Thus, a very different phenomenology, such as large top mass running and signals in four top final states, is introduced, which will be discussed in detail. With the assistance of this mechanism, the solution to the hierarchy problem can be pushed to a (well-defined) higher scale, and a final test of naturalness might be deferred to a 100 TeV Collider, like the FCC.

    hep-phhep-exPRD(2023)·18 citations
23. 23*

    New Searches for Muonphilic Particles at Proton Beam Dump Spectrometers

    Diana Forbes🇺🇸 · Christian Herwig🇺🇸 · Yonatan Kahn🇺🇸 · Gordan Krnjaic🇺🇸 · Cristina Mantilla Suarez🇺🇸 · Nhan Tran🇺🇸 · Andrew Whitbeck🇺🇸

    We introduce a new search strategy for visibly decaying muonphilic particles using a proton beam spectrometer modeled after the SpinQuest experiment at Fermilab. In this setup, a $\sim$100 GeV primary proton beam impinges on a thick fixed target and yields a secondary muon beam. As these muons traverse the target material, they scatter off nuclei and can radiatively produce hypothetical muonphilic particles as initial- and final-state radiation. If such new states decay to dimuons, their combined invariant mass can be measured with a downstream spectrometer immersed in a Tesla-scale magnetic field. For a representative setup with $3\times 10^{14}$ muons on target with typical energies of $\sim$ 20 GeV, a $15\%$ invariant mass resolution, and an effective 100 cm target length, this strategy can probe the entire parameter space for which $\sim$ 200 MeV -- GeV scalar particles resolve the muon $g-2$ anomaly. We present sensitivity to these scalar particles at the SpinQuest experiment where no additional hardware is needed and the search could be parasitically executed within the primary nuclear physics program. Future proton beam dump experiments with optimized beam and detector configurations could have even greater sensitivity.

    hep-phhep-exPRD(2023)·26 citations
24. 24*

    The Cosmic Neutrino Background on the Surface of the Earth

    Asimina Arvanitaki🇨🇦 · Savas Dimopoulos🇨🇦

    We argue that the reflection of relic neutrinos from the surface of the Earth results in a significant local $\nu -\bar{\nu }$ asymmetry, far exceeding the expected primordial lepton asymmetry. The net fractional electron neutrino number $\frac{n_{{\nu }_e}-n_{{\bar{\nu }}_e}}{n_{{\nu }_e}}$ is up to $\mathcal{O}(10^5)\sqrt{\frac{m_{\nu }}{0.1\text{eV}}}$ larger than that implied by the baryon asymmetry. This enhancement is due to the weak 4-Fermi repulsion of the ${\nu }_e$ from ordinary matter which slows down the ${\nu }_e$ near the Earth's surface, and to the resulting evanescent neutrino wave that penetrates below the surface. This repulsion thus creates a net ${\nu }_e$ overdensity in a shell $\sim 7\text{meters}\sqrt{\frac{0.1\text{eV}}{m_{\nu }}}$ thick around the Earth's surface. Similarly the repulsion between ${\bar{\nu }}_{\mu }$ or ${\bar{\nu }}_{\tau }$ and ordinary matter creates an overdensity of ${\bar{\nu }}_{\mu ,\tau }$ of similar size. These local enhancements increase the size of $\mathcal{O}(G_F)$ torques of the $C\nu B$ on spin-polarized matter by a factor of order $10^5$. In addition, they create a gradient of the net neutrino density which naturally provides a way out of the forty-year-old ``no-go'' theorems on the vanishing of $\mathcal{O}(G_F)$ forces. The torque resulting from such a gradient force can be $10^8$ times larger than that of earlier proposals. Although the size of these effects is still far from current reach, they may point to new directions for $C\nu B$ detection.

    hep-phastro-ph.COhep-thPRD(2023)·26 citations
25. 25*

    Probing the Mechanism of Neutrinoless Double-Beta Decay in Multiple Isotopes

    Matteo Agostini🇬🇧 · Frank F. Deppisch🇬🇧 · Graham Van Goffrier🇬🇧

    A large experimental program is being mounted to search for neutrinoless double-beta decay over the next decade. Multiple experiments using different target isotopes are being prepared to explore the whole parameter space allowed for inverted-ordered light neutrinos, and have the potential to make discoveries in several other scenarios, including normal-ordered light neutrinos and other exotic mechanisms. We investigate to what extent long-range and exotic short-range contributions may be distinguished by combining measurements of the decay half-life across isotopes. We demonstrate how measurements in two isotopes may facilitate a joint measurement up to a two-fold degeneracy, and how a further measurement in a third isotope may remove this degeneracy. We also highlight the precision of the nuclear matrix elements needed to convert half-lives into information on the underlying decay mechanism. Considering their correlations and uncertainties in the framework of a global Bayesian analysis, we assess the consequences of a possible future 10-fold reduction in uncertainties. Our work motivates an experimental program measuring neutrinoless double-beta decay in more than one isotope, as this would break parameter degeneracies and advance our understanding of particle physics beyond the Standard Model.

    hep-phhep-exnucl-exJHEP(2023)·19 citations
26. 26*

    Feature Selection with Distance Correlation

    Ranit Das🇺🇸 · Gregor Kasieczka🇩🇪 · David Shih🇺🇸

    Choosing which properties of the data to use as input to multivariate decision algorithms -- a.k.a. feature selection -- is an important step in solving any problem with machine learning. While there is a clear trend towards training sophisticated deep networks on large numbers of relatively unprocessed inputs (so-called automated feature engineering), for many tasks in physics, sets of theoretically well-motivated and well-understood features already exist. Working with such features can bring many benefits, including greater interpretability, reduced training and run time, and enhanced stability and robustness. We develop a new feature selection method based on Distance Correlation (DisCo), and demonstrate its effectiveness on the tasks of boosted top- and $W$-tagging. Using our method to select features from a set of over 7,000 energy flow polynomials, we show that we can match the performance of much deeper architectures, by using only ten features and two orders-of-magnitude fewer model parameters.

    hep-phcs.LGhep-exphysics.data-anPRD(2024)·17 citations
27. 27*

    Gravitational wave signatures of PBH-generated baryon-dark matter coincidence

    Basabendu Barman🇵🇱 · Debasish Borah🇮🇳 · Suruj Jyoti Das🇮🇳 · Rishav Roshan🇰🇷

    We propose a new way of probing non-thermal origin of baryon asymmetry of universe (BAU) and dark matter (DM) from evaporating primordial black holes (PBH) via stochastic gravitational waves (GW) emitted due to PBH density fluctuations. We adopt a baryogenesis setup where CP violating out-of-equilibrium decays of a coloured scalar, produced non-thermally at late epochs from PBH evaporation, lead to the generation of BAU. The same PBH evaporation is also responsible for non-thermal origin of superheavy DM. Unlike the case of baryogenesis {\it via leptogeneis} that necessarily corners the PBH mass to $\sim \mathcal{O}(1)$ g, here we can have PBH mass as large as $\sim \mathcal{O}(10^7)$ g due to the possibility of producing BAU directly below sphaleron decoupling temperature. Due to the larger allowed PBH mass we can also have observable GW with mHz-kHz frequencies originating from PBH density fluctuations keeping the model constrained and verifiable at ongoing as well as near future GW experiments like LIGO, BBO, DECIGO, CE, ET etc. Due to the presence of new coloured particles and baryon number violation, the model also has complementary detection prospects at laboratory experiments.

    hep-phastro-ph.COPRD(2023)·43 citations
28. 28*

    New physics in $B\to K^{\ast }{\tau }^{+}{\tau }^{-}$: A model independent analysis

    Neetu Raj Singh Chundawat🇮🇳

    In this work we consider the implications of current $b\to s{\ell }^{+}{\ell }^{-}$ ($\ell =e,\mu$) measurements on several $B\to K^{\ast }{\tau }^{+}{\tau }^{-}$ observables under the assumption that the possible new physics can have both universal as well as nonuniversal couplings to leptons. For new physics solutions which provide a good fit to all $b\to s{\ell }^{+}{\ell }^{-}$ data, we intend to identify observables with large deviations from the Standard Model (SM) predictions as well as to discriminate between various new physics solutions. For this we consider the $B\to K^{\ast }{\tau }^{+}{\tau }^{-}$ branching fraction, the $K^{\ast }$ longitudinal fraction $f_L$, the tau forward-backward asymmetry $A_{FB}$ and the optimized observables in the $P_i^{{(}^{\prime })}$ basis. Further, we construct the $\tau -\mu$ lepton-flavor differences ($Q^{\tau \mu }$) between these tau observables and their muonic counterparts in $B\to K^{\ast }{\mu }^{+}{\mu }^{-}$ decay. Moreover, we also consider lepton-flavor ratios ($R^{\tau \mu }$) of all of these observables. We find that the current data allows for deviations ranging from 25% up to an order of magnitude from the SM value in a number of observables. For e.g., the magnitudes of $Q_{P_3}^{\tau \mu }$ and $Q_{P_8^{\prime }}^{\tau \mu }$ observables can be enhanced up to an order of magnitude, a twofold enhancement in $Q_{A_{FB}}^{\tau \mu }$ is possible along with $\sim$50% enhancement in $R_{K^{\ast }}^{\tau \mu }$ and $\sim$25% in $R_{A_{FB}}^{\tau \mu }$. Moreover, the branching ratio of $B\to K^{\ast }{\tau }^{+}{\tau }^{-}$ can be suppressed up to 25%. A precise measurement of these observables can also discriminate between a number of new physics solutions.

    hep-phPRD(2023)·28 citations
29. 29*

    Medium Response and Jet-Hadron Correlations in Relativistic Heavy-Ion Collisions

    Shanshan Cao🇨🇳 · Guang-You Qin🇨🇳

    High-energy heavy-ion collisions at the Relativistic Heavy-Ion Collider and the Large Hadron Collider have evolved from qualitative understanding into precise extraction of the properties of the Quantum Chromodynamics medium at extremely high temperature. Jet quenching has offered unique insights into the transport properties of the Quark-Gluon Plasma (QGP) created in these energetic collisions. Apart from medium modification of jets, jet-induced medium excitation constitutes another crucial aspect of jet-QGP interaction, and is indispensable in understanding the soft components of jets. We review recent theoretical and phenomenological developments on medium response to jet energy loss, including an overview of both weakly and strongly coupled approaches for describing the thermalization and propagation of energy deposition from jets, effects of medium response on jet observables, and exploration of its unique signatures in jet-hadron correlations. Jet-induced medium excitation is shown to be an essential component in probing the in-medium dynamics of jets and a critical step towards precise extraction of the QGP properties.

    ↳ nucl-thhep-phnucl-exAnn.Rev.Nucl.Part.Sci.(2023)·39 citations
30. 30*

    Probing new physics on the horizon of black holes with gravitational waves

    Elisa Maggio🇮🇹

    Black holes are the most compact objects in the Universe. According to general relativity, black holes have a horizon that hides a singularity where Einstein's theory breaks down. Recently, gravitational waves opened the possibility to probe the existence of horizons and investigate the nature of compact objects. This is of particular interest given some quantum-gravity models which predict the presence of horizonless and singularity-free compact objects. Such exotic compact objects can emit a different gravitational-wave signal relative to the black hole case. In this thesis, we analyze the stability of horizonless compact objects, and derive a generic framework to compute their characteristic oscillation frequencies. We provide an analytical, physically-motivated template to search for the gravitational-wave echoes emitted by these objects in the late-time postmerger signal. Finally, we infer how extreme mass-ratio inspirals observable by future gravitational-wave detectors will allow for model-independent tests of the black hole paradigm.

    ↳ gr-qcastro-ph.HEhep-phhep-th4 citations
31. 31*

    Path-integrals of perturbative superstrings on curved backgrounds from string geometry theory

    Matsuo Sato🇯🇵 · Kunihito Uzawa🇯🇵

    String geometry theory is one of the candidates of the non-perturbative formulation of string theory. In this paper, from the string geometry theory, we derive path-integrals of perturbative superstrings on all the string backgrounds, $G_{\mu \nu }(x)$ and $B_{\mu \nu }(x)$, by considering fluctuations around the string background configurations, which are parametrized by the string backgrounds.

    ↳ hep-thgr-qchep-phmath.DG+1PRD(2023)·8 citations
32. 32*

    Impact of galactic distributions in celestial capture of dark matter

    Debajit Bose🇮🇳 · Sambo Sarkar🇮🇳

    Celestial capture of dark matter provides a useful handle for constraining its particulate properties. The capture formalism is sensitive to the phase space distribution of dark matter in the vicinity of the celestial object. This article aims to systematically study the impact of uncertainties and the influence of cosmological simulations on the rate at which dark matter particles are captured inside a variety of celestial objects. Going beyond the framework of the Maxwell-Boltzmann distribution or the standard halo model, we take up pragmatic dark matter velocity distributions motivated by observations or cosmological simulations. Within the limits of the standard halo model, we report a maximum $\sim 20\%$ change in the capture rate. This number can go up to $\sim 200\%$ if dark matter particles within the galactic halo are favored to have an empirical velocity distribution profile when well-resolved and sophisticated cosmological simulations are employed to extract their parametric values.

    ↳ astro-ph.COastro-ph.GAastro-ph.SRhep-phPRD(2023)·28 citations
33. 33*

    QED Fermions in a noisy magnetic field background

    Jorge David Castaño-Yepes🇨🇱 · Marcelo Loewe🇨🇱 · Enrique Muñoz🇨🇱 · Juan C. Rojas🇨🇱 · Renato Zamora🇨🇱

    We consider the effects of a noisy magnetic field background over the fermion propagator in QED, as an approximation to the spatial inhomogeneities that would naturally arise in certain physical scenarios, such as heavy-ion collisions or the quark-gluon plasma in the early stages of the evolution of the Universe. We considered a classical, finite and uniform average magnetic field background $⟨\mathbf{B}(\mathbf{x})⟩=\mathbf{B}$, subject to white-noise spatial fluctuations with auto-correlation of magnitude ${\Delta }_B$. By means of the Schwinger representation of the propagator in the average magnetic field as a reference system, we used the replica formalism to study the effects of the magnetic noise in the form of renormalized quasi-particle parameters, leading to an effective charge and an effective refraction index, that depend not only on the energy scale, as usual, but also on the magnitude of the noise ${\Delta }_B$ and the average field $\mathbf{B}$.

    ↳ hep-thhep-phPRD(2023)·18 citations
34. 34*

    Progress in calculation of the fourth Mellin moment of the pion light-cone distribution amplitude using the HOPE method

    William Detmold🇺🇸 · Anthony V. Grebe🇺🇸 · Issaku Kanamori🇯🇵 · C.-J. David Lin🇹🇼 · Robert J. Perry🇪🇸 · Yong Zhao🇺🇸

    The pion light-cone distribution amplitude (LCDA) is a central non-perturbative object of interest for the calculation of high-energy exclusive processes in quantum chromodynamics. This article describes the progress in the lattice QCD calculation of the fourth Mellin moment of the pion LCDA using a heavy-quark operator product expansion (HOPE).

    ↳ hep-lathep-phnucl-thPoS(2023)·2 citations
35. 35*

    Neutron detection and application with a novel 3D-projection scintillator tracker in the future long-baseline neutrino oscillation experiments

    S. Gwon🇰🇷 · P. Granger🇫🇷 · G. Yang🇺🇸 · S. Bolognesi🇫🇷 · T. Cai🇺🇸 · M.Danilov🇷🇺 · A.Delbart🇫🇷 · A. De Roeck🇨🇭 · S. Dolan🇨🇭 · G. Eurin🇫🇷 · R.F. Razakamiandra🇲🇬 · S. Fedotov🇷🇺 and 38 other authors

    Neutrino oscillation experiments require a precise measurement of the neutrino energy. However, the kinematic detection of the final-state neutron in the neutrino interaction is missing in current neutrino oscillation experiments. The missing neutron kinematic detection results in a feed-down of the detected neutrino energy compared to the true neutrino energy. A novel 3D\textcolor{black}{-}projection scintillator tracker, which consists of roughly ten million active cubes covered with an optical reflector, is capable of measuring the neutron kinetic energy and direction on an event-by-event basis using the time-of-flight technique thanks to the fast timing, fine granularity, and high light yield. The ${\bar{\nu }}_{\mu }$ interactions tend to produce neutrons in the final state. By inferring the neutron kinetic energy, the ${\bar{\nu }}_{\mu }$ energy can be reconstructed better, allowing a tighter incoming neutrino flux constraint. This paper shows the detector's ability to reconstruct neutron kinetic energy and the ${\bar{\nu }}_{\mu }$ flux constraint achieved by selecting the charged-current interactions without mesons or protons in the final state.

    ↳ hep-exhep-phphysics.ins-detPRD(2023)·12 citations
36. 36*

    Intermediate window observable for the hadronic vacuum polarization contribution to the muon $g-2$ from O$(a)$ improved Wilson quarks

    Marco Cè🇨🇭 · Antoine Gérardin🇫🇷 · Georg von Hippel🇩🇪 · Renwick J. Hudspith🇩🇪 · Simon Kuberski🇩🇪 · Harvey B. Meyer🇩🇪 · Kohtaroh Miura🇩🇪 · Daniel Mohler🇩🇪 · Konstantin Ottnad🇩🇪 · Srijit Paul🇩🇪 · Andreas Risch🇩🇪 · Teseo San José🇩🇪 · Hartmut Wittig🇩🇪

    Following the publication of the new measurement of the anomalous magnetic moment of the muon, the discrepancy between experiment and the theory prediction from the $g-2$ theory initiative has increased to $4.2\sigma$. Recent lattice QCD calculations predict values for the hadronic vacuum polarization contribution that are larger than the data-driven estimates, bringing the Standard Model prediction closer to the experimental measurement. Euclidean time windows in the time-momentum representation of the hadronic vacuum polarization contribution to the muon $g-2$ can help clarify the discrepancy between the phenomenological and lattice predictions. We present our calculation of the intermediate distance window contribution using $N_{\mathrm{f}}=2+1$ flavors of O$(a)$ improved Wilson quarks. We employ ensembles at six lattice spacings below $0.1$fm and pion masses down to the physical value. We present a detailed study of the continuum limit, using two discretizations of the vector current and two independent sets of improvement coefficients. Our result at the physical point displays a tension of $3.9\sigma$ with a recent evaluation of the intermediate window based on the data-driven method.

    ↳ hep-lathep-phPoS(2023)·2 citations
37. 37*

    Vortex-bound solitons in topological superfluid ${}^3$He

    J. T. Mäkinen · K. Zhang🇨🇳 · V. B. Eltsov

    The different superfluid phases of ${}^3$He are described by $p$-wave order parameters that include anisotropy axes both in the orbital and spin spaces. The anisotropy axes characterize the broken symmetries in these macroscopically coherent quantum many-body systems. The systems' free energy has several degenerate minima for certain orientations of the anisotropy axes. As a result, spatial variation of the order parameter between two such regions, settled in different energy minima, forms a topological soliton. Such solitons can terminate in the bulk liquid, where the termination line forms a vortex with trapped circulation of mass and spin superfluid currents. Here we discuss possible soliton-vortex structures based on the symmetry and topology arguments and focus on the three structures observed in experiments: solitons bounded by spin-mass vortices in the B phase, solitons bounded by half-quantum vortices in the polar and polar-distorted A phases, and the composite defect formed by a half-quantum vortex, soliton and the Kibble-Lazarides-Shafi wall in the polar-distorted B phase. The observations are based on nuclear magnetic resonance (NMR) techniques and are of three types: first, solitons can form a potential well for trapped spin waves, observed as an extra peak in the NMR spectrum at shifted frequency; second, they can increase the relaxation rate of the NMR spin precession; lastly, the soliton can present the boundary conditions for the anisotropy axes in bulk, modifying the bulk NMR signal. Owing to solitons' prominent NMR signatures and the ability to manipulate their structure with external magnetic field, solitons have become an important tool for probing and controlling the structure and dynamics of superfluid ${}^3$He, in particular half-quantum vortices with core-bound Majorana modes.

    ↳ cond-mat.otherhep-phmath-phmath.MP+1J.Phys.Condens.Matter(2023)·5 citations
38. 38*

    Lifetime of the hypertriton

    D. Gazda🇨🇿 · A. Pérez-Obiol🇪🇸 · A. Gal🇮🇱 · E. Friedman🇮🇱

    Conflicting values of the hypertriton lifetime $\tau ({}_{\Lambda }^3\mathrm{H})$ were derived in relativistic heavy ion (RHI) collision experiments over the last decade. A very recent ALICE Collaboration measurement is the only experiment where the reported $\tau ({}_{\Lambda }^3\mathrm{H})$ comes sufficiently close to the free-$\Lambda$ lifetime ${\tau }_{\Lambda }$,as expected naively for a very weakly bound $\Lambda$ in ${}_{\Lambda }^3\mathrm{H}$. We revisited theoretically this ${}_{\Lambda }^3\mathrm{H}$ lifetime puzzle, using ${}_{\Lambda }^3\mathrm{H}$ and ${}^3\mathrm{He}$ wave functions computed within the abinitio no-core shell model employing interactions derived from chiral effective field theory to calculate the two-body decay rate $\Gamma ({}_{\Lambda }^3\mathrm{H}\to {}^3\mathrm{He}+{\pi }^{-})$. We found significant but opposing contributions arising from $\Sigma NN$ admixtures in ${}_{\Lambda }^3\mathrm{H}$ and from ${\pi }^{-}-{}^3\mathrm{He}$ final-state interaction. To derive $\tau ({}_{\Lambda }^3\mathrm{H})$, we evaluated the inclusive ${\pi }^{-}$ decay rate ${\Gamma }_{{\pi }^{-}}({}_{\Lambda }^3\mathrm{H})$ by using the measured branching ratio $\Gamma ({}_{\Lambda }^3\mathrm{H}\to {}^3\mathrm{He}+{\pi }^{-})/{\Gamma }_{{\pi }^{-}}({}_{\Lambda }^3\mathrm{H})$ and added the ${\pi }^0$ contributions through the $\Delta I=\frac{1}{2}$ rule. The resulting $\tau ({}_{\Lambda }^3\mathrm{H})$ varies strongly with the rather poorly known $\Lambda$ separation energy $E_{\mathrm{sep}}({}_{\Lambda }^3\mathrm{H})$ and it is thus possible to associate each one of the distinct RHI $\tau ({}_{\Lambda }^3\mathrm{H})$ measurements with its own underlying value of $E_{\mathrm{sep}}({}_{\Lambda }^3\mathrm{H})$.

    ↳ nucl-thhep-phnucl-exEPJ Web Conf.(2022)·1 citation
39. 39*

    Vortex rings in heavy-ion collisions at energies $\sqrt{s_{NN}}=$ 3--30 GeV and possibility of their observation

    Yu. B. Ivanov🇷🇺

    The ring structures that appear in Au+Au collisions at collision energies $\sqrt{s_{NN}}=$ 3 -- 30 GeV are studied. The calculations are performed within the model of three-fluid dynamics. It is demonstrated that a pare of vortex rings are formed, one at forward and another at backward rapidities, in ultra-central Au+Au collisions at $\sqrt{s_{NN}}>$ 4 GeV. The vortex rings carry information about early stage of the collision, in particular about the stopping of baryons. It is shown that these rings can be detected by measuring the ring observable $R_{\Lambda }$ even in rapidity range $0<y<0.5$ (or $-0.5<y<0$) on the level of 0.5--1.5\% at $\sqrt{s_{NN}}=$ 5 -- 20 GeV. At forward/backward rapidities, the $R_{\Lambda }$ signal is expected to be stronger. Possibility of observation of the vortex-ring signal against background of non-collective transverse polarization is discussed.

    ↳ nucl-thhep-phnucl-exPRC(2023)·6 citations
40. 40*

    Reflections on Parity Breaking

    Jacob McNamara🇺🇸 · Matthew Reece🇺🇸

    Parity and CP symmetries are broken in the world around us. Nonetheless, parity (or CP) may be a gauge symmetry which is higgsed in our universe. This is assumed in many scenarios for physics beyond the Standard Model, including the classic Nelson--Barr proposal for the Strong CP problem. Gauged parity can only arise in quantum gravity, where it corresponds to a path integral over both orientable and non-orientable spacetime manifolds. We show that spontaneous breaking of gauged parity leads to exactly stable domain walls, and describe the implications for the cosmology of models with gauged parity. These domain walls carry an unusual sort of charge, which superficially has features in common with both gauge charges and global charges. We show that these unusual charges are consistent with the expected absence of global symmetries in quantum gravity when there exists a complete spectrum of dynamical objects required by the Swampland Cobordism Conjecture, including end-of-the-world branes.

    ↳ hep-thhep-ph54 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.