Tue·Aug 9, 2022Tuesday·August 9, 2022

1. 01*

   Unanswered Questions in Charmed Baryon Physics

   John M Yelton🇺🇸

   This is an experimentalist's list of questions concerning the physics of the charmed baryon sector which have no satisfactory answer.

   hep-phhep-ex0 citations
2. 02*

   CP Violation in Charmed and Bottom Baryon Physics

   John M Yelton🇺🇸

   This is an experimentalist's view of the recent results on, and prospects for, CP Violation in charmed and bottom baryons

   hep-phhep-ex1 citation
3. 03*

   On direct observation of millicharged particles at $c$-$\tau$ factories and other $e^{+}{e}^{-}$-colliders

   Dmitry Gorbunov🇷🇺 · Dmitry Kalashnikov🇷🇺 · Pavel Pakhlov🇷🇺 · Timofey Uglov🇷🇺

   Hypothetical particles with tiny electric charges (millicharged particles or MCPs) can be produced in electron-positron annihilation if kinematically allowed. Typical searches for them at $e^{+}{e}^{-}$ colliders exploit a signature of a single photon with missing energy carried away by the undetected MCP pair. We put forward an idea to look alternatively for MCP energy deposits inside a tracker, which is a direct observation. The new signature is relevant for non-relativistic MCPs, and we illustrate its power on the example of the $c$-$\tau$ factory, where we argued that the corresponding searches may be background-free. We find that it can probe the MCP charge down to $3\times 10^{-3}$ of the electron charge for the MCP masses in $\mathcal{O}(5)$ MeV vicinity of each energy beam value where the factory will collect a luminosity of 100 fb${}^{-1}$ in one year. This mass region is unreachable with the searches for missing energy and single photon.

   hep-phPLB(2023)·9 citations
4. 04*

   One-loop radiative correction to the Toshev relation for neutrino oscillations in matter

   Zhi-zhong Xing (1, 2 and 3)🇨🇳 · Jun-yu Zhu (1 and 2) ((1) Institute of High Energy Physics, Chinese Academy of Sciences, (2) School of Physical Sciences, University of Chinese Academy of Sciences, (3) Center for High Energy Physics, Peking University)🇨🇳

   The one-loop electroweak radiative corrections to coherent forward neutrino scattering in a medium slightly violates the tree-level universality of neutral-current contributions of three neutrino flavors to the matter potential that is relevant to neutrino oscillations in matter. We examine this small but nontrivial quantum effect by deriving the differential equations of those effective neutrino oscillation quantities with respect to the electron number density of matter. The tree-level Toshev relation $\sin 2{\tilde{\theta }}_{23}\sin \tilde{\delta }=\sin 2{\theta }_{23}\sin \delta$, which links the fundamental flavor-mixing and CP-violating parameters

   hep-ph2 citations
5. 05*

   Two-loop mixed QCD-EW corrections to neutral current Drell-Yan

   Simone Devoto🇮🇹

   We present the mixed QCD-EW two-loop virtual amplitudes for the neutral current Drell-Yan production, one of the bottlenecks for the complete calculation of the NNLO mixed QCD-EW corrections. We present the computational details and the first steps towards their automation. We describe the evaluation of all the relevant two-loop Feynman integrals using analytical and semi-analytical methods, the subtraction of the universal infrared singularities and present the numerical evaluation of the finite remainder.

   hep-phPoS(2022)·1 citation
6. 06*

   Dark Energy and Neutrino Superfluids

   Andrea Addazi🇨🇳 · Salvatore Capozziello🇮🇹 · Qingyu Gan🇨🇳 · Antonino Marcianò🇨🇳

   We show that the neutrino mass, the dark matter and the dark energy can be explained in a unified framework, postulating a new invisible Born-Infeld field, which we name "non-linear dark photon", undergoing a meV-scale dynamical transmutation and coupled to neutrinos. Dark energy genesis is dynamically explained as a byproduct of the dark photon condensation, inducing the bare massless neutrinos to acquire an effective mass around the meV scale. It is fascinating to contemplate the channel induced by the non-linear dark photon leading to the pairing of the non-relativistic neutrinos, hence generating a cosmological superfluid state. As a consequence, the appearance of a light neutrino composite boson is predicted, providing a good cold dark matter candidate. In particular, if our model is enriched by an extra global Lepton number $U_L(1)$ symmetry, then the neutrino pair can be identified with a composite Majoron field with intriguing phenomenological implications for the neutrinoless-double-beta-decay ($0\nu \beta \beta$). Our model carries interesting phenomenological implications since dark energy, dark matter and the neutrino mass are time-varying dynamical variables, as a consequence of the non-linear Born-Infeld interaction terms. Limits arising from PLANCK+SNe+BAO collaborations data are also discussed. Finally, our model allows for an inverse hierarchy of neutrino masses, with interesting implications for the JUNO experiment.

   hep-phastro-ph.COgr-qchep-thPhys.Dark Univ.(2022)·12 citations
7. 07*

   Impact of Nuclear effects in Energy Reconstruction Methods on Sensitivity of Neutrino Oscillation Parameters at NO$\nu$A experiment

   Paramita Deka🇮🇳 · Jaydip Singh🇮🇳 · Kalpana Bora🇮🇳

   Long baseline (LBL) neutrino experiments aim to measure the neutrino oscillation parameters to high precision. These experiments use nuclear targets for neutrino scattering and hence are inflicted with complexities of nuclear effects. Nuclear effects and their percolation into sensitivity measurement of neutrino oscillations parameters are not yet fully understood and therefore need to be dealt with carefully. In a recent work [1], we reported some results on this for NO$\nu$A experiment using the kinematic method of neutrino energy reconstruction, where it was observed that the nuclear effects are important in sensitivity analysis, and inclusion of realistic detector setup specifications increases uncertainty in this analysis as compared to ideal detector case. With this motivation, in this work, we use two methods of neutrino energy reconstruction - kinematic and calorimetric, including the nuclear effects, and study their impact on sensitivity analysis. We consider nuclear interactions such as RPA and 2p2h and compare two energy reconstruction methods with reference to events generation, measurement of neutrino oscillation parameters $\Delta m_{32}^2$ and ${\theta }_{23}$ for disappearance channel, mass hierarchy sensitivity, and CP-violation sensitivity for appearance channel of the NO$\nu$A experiment. It is observed that with an ideal detector setup, the kinematic method shows significant dependence on nuclear effects compared to the calorimetric method. We also investigate the impact of realistic detector setup for NO$\nu$A in these two methods (with nuclear effects) and find that the calorimetric method shows more bias (uncertainty increases) in sensitivity contours, as compared to the kinematic method. This is found to be true for both the mass hierarchies and for both neutrino and antineutrino incoming beams.

   hep-phNPB(2023)·3 citations
8. 08*

   Molecular states of $D^{\ast }{D}^{\ast }{\bar{K}}^{\ast }$ nature

   N. Ikeno🇯🇵 · M. Bayar🇹🇷 · E. Oset🇪🇸

   We study the interaction of two $D^{\ast }$ and a ${\bar{K}}^{\ast }$ by using the Fixed Center Approximation to the Faddeev equations to search for bound states of the three body system. Since the $D^{\ast }{D}^{\ast }$ interaction is attractive and gives a bound state, and so is the case of the $D^{\ast }{\bar{K}}^{\ast }$ interaction, where the $J^P=0^{+}$ bound state is identified with the $X_0(2900)$, the $D^{\ast }{D}^{\ast }{\bar{K}}^{\ast }$ system leads to manifestly exotic bound states with $ccs$ open quarks. We obtain bound states of isospin $I=1/2$, negative parity and total spin $J=0,1,2$. For $J=0$ we obtain one state, and for $J=1,2$ we obtain two states in each case. The binding energies range from $56$ MeV to $151$ MeV and the widths from $80$ MeV to $100$ MeV.

   hep-phPRD(2023)·15 citations
9. 09*

   Flavour bounds on the flavon of a minimal and a non-minimal ${\mathcal{Z}}_2\times {\mathcal{Z}}_N$ symmetry

   Gauhar Abbas🇮🇳 · Vartika Singh🇮🇳 · Neelam Singh🇮🇳 · Ria Sain🇮🇳

   We investigate flavour bounds on the ${\mathcal{Z}}_2\times {\mathcal{Z}}_5$ and ${\mathcal{Z}}_2\times {\mathcal{Z}}_9$ flavour symmetries. These flavour symmetries are a minimal and a non-minimal forms of the ${\mathcal{Z}}_2\times {\mathcal{Z}}_N$ flavour symmetry, that can provide a simple set-up for the Froggatt-Nielsen mechanism. The ${\mathcal{Z}}_2\times {\mathcal{Z}}_5$ and ${\mathcal{Z}}_2\times {\mathcal{Z}}_9$ flavour symmetries are capable of explaining the fermionic masses and mixing pattern of the standard model including that of the neutrinos. The bounds on the parameter space of the flavon field of the ${\mathcal{Z}}_2\times {\mathcal{Z}}_5$ and ${\mathcal{Z}}_2\times {\mathcal{Z}}_9$ flavour symmetries are derived using the current quark and lepton flavour physics data and future projected sensitivities of quark and lepton flavour effects. The strongest bounds on the flavon of the ${\mathcal{Z}}_2\times {\mathcal{Z}}_5$ symmetry come from the $D^0-{\bar{D}}^0$ mixing. The bounds on the ${\mathcal{Z}}_2\times {\mathcal{Z}}_9$ flavour symmetry are stronger than that of the minimal ${\mathcal{Z}}_2\times {\mathcal{Z}}_5$ symmetry. The ratio $R_{\mu \mu }$ provides rather robust bounds on the flavon parameters in the future phase-\rom{1} and phase-\rom{2} of the LHCb by leaving only a very small region in the allowed parameter space of the models.

   hep-phhep-exEPJC(2023)·13 citations
10. 10*

    Damping of neutrino oscillations, decoherence and the lengths of neutrino wave packets

    Evgeny Akhmedov🇩🇪 · Alexei Y. Smirnov (Max-Planck-Inst. fuer Kernphysik, Heidelberg)🇩🇪

    Spatial separation of the wave packets (WPs) of neutrino mass eigenstates leads to decoherence and damping of neutrino oscillations. Damping can also be caused by finite energy resolution of neutrino detectors or, in the case of experiments with radioactive neutrino sources, by finite width of the emitted neutrino line. We study in detail these two types of damping effects using reactor neutrino experiments and experiments with radioactive ${}^{51}$Cr source as examples. We demonstrate that the effects of decoherence by WP separation can always be incorporated into a modification of the energy resolution function of the detector and so are intimately entangled with it. We estimate for the first time the lengths ${\sigma }_x$ of WPs of reactor neutrinos and neutrinos from a radioactive ${}^{51}$Cr source. The obtained values, ${\sigma }_x=(2\times 10^{-5}-1.4\times 10^{-4})$ cm, are at least six orders of magnitude larger than the currently available experimental lower bounds. We conclude that effects of decoherence by WP separation cannot be probed in reactor and radioactive source experiments.

    hep-phhep-exJHEP(2022)·40 citations
11. 11*

    Percolation leads to finite-size effects on the transition temperature and center of mass energy required for the quark-gluon plasma formation

    J. C. Texca García🇲🇽 · D. Rosales Herrera🇲🇽 · J. E. Ramírez🇲🇽 · A. Fernández Téllez🇲🇽 · C. Pajares🇪🇸

    We investigate the finite-size effects on the transition temperature associated with the quark-gluon plasma (QGP) formation. From a percolation perspective, the onset of the QGP in high-energy collisions occurs when the spanning cluster of color strings emerges. The principal result presented here is the finite-size effects on the transition temperature expressed as a power law in terms of the nucleon number. We found that the transition temperature is higher for small systems than for large ones. It means that minimal triggering conditions events in pp collisions require about twenty times higher energies than AuAu-PbPb collisions. We also estimate the center of mass energy required for the QGP formation as a function of the nucleon number. Our results are consistent with the minimal center of mass energies at which the QGP has been observed.

    hep-phcond-mat.dis-nnPRD(2022)·11 citations
12. 12*

    Neutron-Mirror-Neutron Oscillation and Neutron Star Cooling

    Itzhak Goldman🇮🇱 · Rabindra N. Mohapatra🇺🇸 · Shmuel Nussinov🇮🇱 · Yongchao Zhang🇨🇳

    It was pointed out in a recent paper that the observed cooling rate of old, cold neutron stars (NS) can provide an upper limit on the transition rate of neutron to mirror neutron ($n-n^{\prime }$). This limit is so stringent that it would preclude any discovery of $n\to n^{\prime }$ oscillation in the current round of terrestrial searches for the process. Motivated by this crucially important conclusion, we critically analyze this suggestion and note an interesting new effect present in nearly exact mirror models for $n\to n^{\prime }$ oscillation, which significantly affect this bound. The new element is the $\beta$ decay $n^{\prime }\to p^{\prime }+e^{\prime }+{\bar{\nu }}_e^{\prime }$, which creates a cloud of mirror particles $n^{\prime }$, $p^{\prime }$, $e^{\prime }$ and $D^{\prime }$ inside the NS core. The $e^{\prime }$ can "rob" the energy generated by the $n\to n^{\prime }$ transition via $e-e^{\prime }$ scattering enabled by the presence of a (minute) milli-charge in mirror particles. This energy is emitted as unobserved mirror photons via fast mirror bremsstrahlung leading to a relaxation of this upper limit.

    hep-phastro-ph.HEhep-exnucl-thPRL(2022)·15 citations
13. 13*

    Implications of Recent KATRIN Results for Lower-Limits on Neutrino Masses

    Ephraim Fischbach🇺🇸 · Dennis E. Krause🇺🇸 · Quan Le Thien🇺🇸 · Carol Scarlett🇺🇸

    Recently announced results from the KATRIN collaboration imply an upper bound on the effective electron anti-neutrino mass $m_{{\nu }_e}$, $m_{{\nu }_e}<0.8\mathrm{eV}/c^2$. Here we explore the implications of combining the KATRIN upper bound using a previously inferred lower bound on the smallest neutrino mass state, $m_{i,\min }\gtrsim 0.4\mathrm{eV}/c^2$ implied by the stability of white dwarfs and neutron stars in the presence of long-range many-body neutrino-exchange forces. By combining a revised lower bound estimate with the expected final upper bound from KATRIN, we find that the available parameter space for $m_{{\nu }_e}$ may be closed completely within the next few years. We then extend the argument when a single light sterile neutrino flavor is present to set a lower mass limit on sterile neutrinos.

    hep-ph1 citation
14. 14*

    Pion inspired by QCD: Nakanishi and Light-Front Integral Representations

    R.M. Moita🇧🇷 · J.P.B.C. de Melo🇧🇷 · T. Frederico🇧🇷 · W. de Paula🇧🇷

    The pion structure in Minkowski space is explored using the Nakanishi integral representation. A general framework is developed for the pion Bethe-Salpeter amplitude based on the Kallen-Lehmann representation of the dressed quarks with an ansatz for the pseudo-scalar $\pi -q\bar{q}$ vertex fulfilling the axial Ward-Takahashi identity. The Nakanishi weight functions are derived for the scalar amplitudes associated with the decomposition of the pion Bethe-Salpeter amplitude in different operator bases in the Dirac spinor space in terms of the involved spectral densities. The approach is applied to an analytical model of the pion Bethe-Salpeter amplitude, which is combined with Landau gauge lattice QCD results for the quark running mass at space-like momentum. From the Nakanishi integral representation several pion observables were calculated, such as the decay constant, the spin decomposition of the valence probabilities, longitudinal and transverse momentum distributions from the valence component of the light-front wave function.

    hep-phhep-thnucl-thPRD(2022)·5 citations
15. 15*

    Reformulation of the twist-3 gluon Sivers effect toward the application to the heavy quarkonium production

    Shinsuke Yoshida🇨🇳 · Difei Zheng🇨🇳

    In this paper, we propose a new calculation method for the twist-3 gluon Sivers effect within the collinear factorization approach. The method called pole calculation has been used to derive the cross section formula for the single transverse-spin asymmetry(SSA) as a standard method. We point out that we encounter a problem when we try to apply the pole calculation to the SSA in the heavy quarkonium production whose hadronization mechanism is described by non-relativistic QCD(NRQCD) framework. We show that the new calculation method solves this problem and successfully reproduces known results derived by the pole calculation. Our new method extends the applicability of the twist-3 calculation technique to heavy quarkonium productions which are ideal observables for the investigation of the gluon Sivers effect.

    hep-phPRD(2022)·3 citations
16. 16*

    The double thresholds distort the lineshapes of the $P_{\psi s}^{\Lambda }(4338{)}^0$ resonance

    Lu Meng🇩🇪 · Bo Wang🇨🇳 · Shi-Lin Zhu🇨🇳

    Very recently, the LHCb Collaboration reported the first observation of the hidden charm pentaquark with strangeness, $P_{\psi s}^{\Lambda }(4338{)}^0$. Considering this state is very close to the ${\Xi }_c^0{\bar{D}}^0$ and ${\Xi }_c^{+}{D}^{-}$ thresholds, we explore the possible bias of the Breit-Wigner parameterization, with emphasis on the effect of its coupling to the double thresholds ${\Xi }_c^0{\bar{D}}^0$ and ${\Xi }_c^{+}{D}^{-}$. We first use a qualitative picture based on the ``uniformization" of the Riemann surface of the two-channel system to understand the positions of the enhancement. Then we use the Lippmann-Schwinger equation (LSE) formalism (equivalent to the $K$-matrix parameterization) with two models, the zero-range model and Flatté model to investigate the $J/\psi \Lambda$ lineshapes. Our results show that the nominal peak of the $P_{\psi s}^{\Lambda }(4338{)}^0$ could arise either from the pole well above the ${\Xi }_c^{+}{D}^{-}$ threshold on the $(-,+)$ sheet or from the pole well below the ${\Xi }_c^0{\bar{D}}^0$ threshold on the $(-,-)$ sheet in the two-channel system. Using the Breit-Wigner distribution to depict the above two lineshapes could be misleading. We also find a novel type of lineshapes with the enhancement constrained by the threshold difference. We urge the LHCb collaboration to perform the refined experimental analysis considering the unitarity and analyticity, e.g. using the K-matrix parameterization. As a by-product, we obtain that the ratio of the isospin violating decay ${\Gamma }_{P_{\psi s}^{\Lambda }\to J/\psi \Sigma }/{\Gamma }_{P_{\psi s}^{\Lambda }\to J/\psi \Lambda }$ could be up to $10\%$.

    hep-phhep-exPRD(2023)·48 citations
17. 17*

    Spectroscopy behavior of fully heavy tetraquarks

    Hong-Tao An🇨🇳 · Si-Qiang Luo🇨🇳 · Zhan-Wei Liu🇨🇳 · Xiang Liu🇨🇳

    Stimulated by the observation of the $X(6900)$ from LHCb in 2020 and the recent results from CMS and ATLAS in the di-$J/\psi$ invariant mass spectrum, in this work we systemically study all possible configurations for the ground fully heavy tetraquark states in constituent quark model. By our calculation, we present their spectroscopy behaviors like binding energy, lowest meson-meson thresholds, specific wave function, magnetic moment, transition magnetic moment, radiative decay width, rearrangement strong width ratio, internal mass contributions, relative lengths between (anti)quarks, and the spatial distribution of four valence (anti)quarks. We cannot find stable S-wave state for the fully heavy tetraquark system. We hope that our results are valuable to further explore fully heavy tetraquark states in experiment.

    hep-phhep-exEPJC(2023)·53 citations
18. 18*

    Triangle singularity in $B^0\to {\pi }^{-}{K}^{+}X(3872)$ via the $D_{s1}\bar{D}{D}^{\ast }$ loop and possible precise measurement of the $X(3872)$ mass

    Mao-Jun Yan🇨🇳 · Ying-Hui Ge🇨🇳 · Xiao-Hai Liu🇨🇳

    We investigate the $B^0\to {\pi }^{-}{K}^{+}X(3872)$ decay via the $D_{s1}(2536)\bar{D}{D}^{\ast }$ rescattering diagram. The line shape of the $K^{+}X(3872)$ distribution curve around $D_{s1}(2536)\bar{D}$ threshold is very sensitive to the $X(3872)$ mass because the triangle singularity (TS) can be generated from the loop. By means of this characteristic, we can determine whether the $X(3872)$ mass is below or above the $D^{\ast 0}{\bar{D}}^0$ threshold with high precision. The narrowness of $D_{s1}(2536)$ in the loop is one of the key reasons why the TS mechanism of measuring the $X(3872)$ mass may work. The $X(3872)$ width impact on the $K^{+}X(3872)$ line shape is also crucial in the TS mechanism. If the width is as large as 1 MeV, the proposed method of measuring the $X(3872)$ mass would be ruined.

    hep-phhep-exPRD(2022)·12 citations
19. 19*

    Fate of the first-order chiral phase transition in QCD: Implications for dark QCD studied via a Nambu-Jona-Lasinio model

    Yuanyuan Wang🇨🇳 · Mamiya Kawaguchi🇨🇳 · Shinya Matsuzaki🇨🇳 · Akio Tomiya🇯🇵

    The first-order nature of the chiral phase transition in QCD-like theories can play crucial roles to address a dark side of the Universe, where the created out-of equilibrium is essential to serve as cosmological and astrophysical probes such as gravitational wave productions, which have extensively been explored. This interdisciplinary physics is built based on a widely-accepted conjecture that the thermal chiral phase transition in QCD-like theories with massless (light) three flavors is of first order. We find that such a first order feature may not hold, when ordinary or dark quarks are externally coupled to a weak enough background field of photon or dark photon (which we collectively call a ``magnetic" field). We assume that a weak ``magnetic" background field could be originated from some ``magnetogenesis" in the early Universe. We work on a Nambu-Jona-Lasinio model which can describe the chiral phase transition in a wide class of QCD-like theories. We show that in the case with massless (light) three flavors, the first-order feature goes away when $2f_{\pi }^2\lesssim eB(\ll (4\pi f_{\pi }{)}^2)$, where $eB$ is the ``magnetic" field strength and $f_{\pi }$ the pion decay constant at the vacuum. This disappearance is the generic consequence of the presence of the ``magnetically" induced scale anomaly and the ``magnetic" catalysis for the chiral symmetry breaking, and would impact or constrain modeling dark QCD coupled to an external ``magnetic" field.

    hep-phastro-ph.COhep-thnucl-thPRD(2022)·4 citations
20. 20*

    Simple Rules for Evanescent Operators in One-Loop Basis Transformations

    Jacky Kumar🇩🇪

    The basis transformations of the effective operators often involve Fierz and other relations which are only valid in $D=4$ space-time dimensions. In general, in $D$ space-time dimensions, however, the evanescent operators have to be introduced to preserve such identities. Such operators contribute to one-loop basis transformations as well as to two-loop renormalization group running. In this talk, I discussed a simple procedure for systematically changing of basis at 1-loop level including shifts due to evanescent operators. As an example, we apply this method to derive the 1-loop basis transformation from the BMU basis useful for NLO QCD calculations, to the JMS basis used in the matching to the SMEFT.

    hep-ph0 citations
21. 21*

    Baryon asymmetry and lower bound on right handed neutrino mass in fast expanding Universe: an analytical approach

    Mainak Chakraborty🇮🇳 · Sourov Roy🇮🇳

    The expansion rate of the Universe deviates from its standard value when the total energy density includes contribution from a new scalar field apart from the radiation energy density. The non-trivial modifications incurred in the Boltzmann equations render the well known analytical solutions unsuitable in non standard scenario. In the present study we derive analytical expressions for the efficiency factor (which is nothing but solution of set of Boltzmann equations) using certain legible approximations. A fair degree of accuracy of these formulas have been observed by juxtaposing the analytical results with that obtained through numerical solution of Boltzmann equations. Faster expansion of the Universe results in decrement of the effective decay parameter which brings down the amount of washout of asymmetry due to inverse decay. Thus in non-standard cosmology scenario, a larger fraction of the asymmetry (generated at early epoch) is expected to survive till present epoch. Alteration of the cosmology does not affect the underlying particle physics model responsible for the generation of the CP asymmetry. Therefore starting from an identical particle physics model we will end up with a larger final baryon asymmetry in the non-standard scenario. It hints towards the possible relaxation of the lower bound of the lightest right handed neutrino mass required to produce adequate asymmetry which is in agreement with current experimental data.

    hep-phJCAP(2022)·14 citations
22. 22*

    Higgs Inflation Using the Unstable Standard Model Potential

    John McDonald🇬🇧

    It is likely that the Higgs potential of the Standard Model is unstable, turning negative at $\varphi <\Lambda \sim 10^{10}$ GeV. Here we consider whether it is possible to have Higgs Inflation on the positive stable region of the potential at $\varphi <\Lambda$. To do this we add a non-minimally coupled induced gravity sector with scalar $\chi$ to the Standard Model. For an appropriate form for the non-minimal coupling of $\chi$, we show that it is possible to have conventional Higgs inflation at small $\varphi <\Lambda$ if the effective Planck mass in the Jordan frame during inflation is sufficiently small, with a phase transition to $\chi \ne 0$ at the end of Higgs inflation which increases the Jordan frame Planck mass to its presently observed value. In the Einstein frame this corresponds to a suppression of the Higgs kinetic and potential term at the end of inflation. We show that the predictions of Higgs inflation at tree level are unaltered from conventional Higgs Inflation, with the exception of the magnitude of the Higgs field during inflation. Hence Higgs Inflation can be achieved using the potential of the unmodified Standard Model.

    hep-phastro-ph.COgr-qchep-thPRD(2023)·2 citations
23. 23*

    Molecular nature of the $a_1$(1260) axial-vector meson

    Samson Clymton🇰🇷 · Hyun-Chul Kim🇰🇷

    We investigate $\pi \rho$ scattering based on the coupled-channel formalism with the $\pi \rho$ and $K{\bar{K}}^{\ast }$ ($\bar{K}{K}^{\ast }$) channels included. We construct the kernel amplitudes by using the meson-exchange model and compute the coupled integral equation for $\pi \rho$ scattering. By performing the partial-wave expansion, we show explicitly that the $a_1(1260)$ meson is dynamically generated by the coupled-channel formalism. The $a_1$ meson only appears by including the $K{\bar{K}}^{\ast }$ ($\bar{K}{K}^{\ast }$) channel. We obtain the pole position of the $a_1$ meson as $\sqrt{s_R}=(1170.7-i173.0)$ MeV. We conclude that the $a_1$ meson can be interpreted as a kaon and vector kaon molecular state.

    hep-phPRD(2022)·14 citations
24. 24*

    Modeling Strangeness Enhancements to resolve the Muon Excess in Cosmic Ray Extensive Air Shower Data

    Julien Manshanden🇩🇪 · Günter Sigl🇩🇪 · Maria V. Garzelli🇩🇪

    Experimental observations of extensive air showers have revealed an excess of the muon content with respect to their theoretical simulations, which we refer to as the muon puzzle. This muon puzzle hampers a precise determination of the ultra-high-energy cosmic ray mass composition. We investigate the potential of producing states of dense quark-gluon matter (which we call fireballs) to resolve the muon puzzle as quantified with data from the Pierre Auger Observatory on the depth of the shower maximum and the number of muons at ground. Adopting a phenomenological fireball model, we find that the inelasticity enhancement associated with the formation of a plasma state is in tension with data on the electromagnetic longitudinal shower development. Instead, we restrict the fireball model to only enhance the strangeness produced in Standard Model hadronic interactions, and dub this model the strangeball model. With an analytic approach based on the Heitler-Matthews model we then find explicit sets of strangeball parameters that resolve the muon puzzle. Constraints from data on shower-to-shower fluctuations of the muon number require strangeness enhancements already at energies accessible to current-generation collider experiments. At Tevatron and LHC energies we estimate 40% of the interactions to produce strangeballs, corresponding to a 5-9% increase of the average fraction of energy retained in the hadronic cascade compared to predictions from current hadronic interaction models. A comparison with relevant measurements of the LHCf and LHCb detectors does not directly exclude this scenario, though the obtained tension with LHCb suggests a stringent test at 14 TeV.

    hep-phJCAP(2023)·14 citations
25. 25*

    CP-violation, Asymmetries and Interferences in $t\bar{t}\varphi$

    Duarte Azevedo🇩🇪 · Rodrigo Capucha🇵🇹 · António Onofre🇵🇹 · Rui Santos🇵🇹

    We use the associated production of top-quark pairs with a generic scalar boson at the LHC to explore the sensitivity of a large set of observables to the sign of the CP mixing angle, present in the coupling between the scalar boson and the top quarks. The mass of the scalar boson is set to $m_{\varphi }=125$ GeV and its coupling to top-quarks is varied such that $\alpha =$ 0${}^{\circ }$, 22.5${}^{\circ }$, 45.0${}^{\circ }$, 67.5${}^{\circ }$, 90.0${}^{\circ }$, 135.0${}^{\circ }$ and 180.0${}^{\circ }$. Dileptonic final states of the $t\bar{t}\varphi$ system are used, with the scalar boson decaying as $\varphi \to b\bar{b}$. A new method to reconstruct the scalar mass, originally designed for the low mass regime is used, improving the resolution of the Higgs mass by roughly a factor of two. A full phenomenological analysis is performed using Standard Model background and signal events generated with MadGraph5aMC@NLO and reconstructed using a kinematical fit. The most sensitive CP-observables are selected to compute Confidence Level (CL) limits as a function of the sign of the top quark Yukawa couplings to the scalar boson. We also explore the sensitivity to interference terms using differential distributions and angular asymmetries. Given the significant difference between the pure scalar and pure pseudo-scalar production cross section values, it is unlikely the $t\bar{t}\varphi$ channel alone will be sensitive to the sign of the CP-mixing angle or interference terms, even at the end of the LHC. Using the $b_2^{t\bar{t}\varphi }$ and $b_4^{t\bar{t}\varphi }$ variables, exclusion limits at 95\% CL for the CP-even and CP-odd components of the top quark Yukawa couplings are expected to be set to $\tilde{\kappa }\in$ [-0.698,+0.698] and $|\kappa |\in$ [0.878,1.04], respectively, at the end of the High Luminosity phase of the LHC (HL-LHC) by using the dileptonic decay channel alone.

    hep-phJHEP(2022)·22 citations
26. 26*

    Neutrino Decoherence and the Mass Hierarchy in the JUNO Experiment

    Eric Marzec🇺🇸 · Joshua Spitz🇺🇸

    The finite size of a neutrino wavepacket at creation can affect its oscillation probability. Here, we consider the electron antineutrino wavepacket and decoherence in the context of the nuclear reactor based experiment JUNO. Given JUNO's high expected statistics [$\sim$100k IBD events (${\bar{\nu }}_{e}p\to e^{+}n$)], long baseline ($\sim$53\,km), and excellent energy resolution [$\sim$$0.03/\sqrt{E_{\mathrm{vis}}(\mathrm{MeV})}$], its sensitivity to the size of the wavepacket is expected to be quite strong. Unfortunately, this sensitivity may weaken the experiment's ability to measure the orientation of the neutrino mass hierarchy for currently allowed values of the wavepacket size. Here, we report both the JUNO experiment's ability to determine the hierarchy orientation in the presence of a finite wavepacket and its simultaneous sensitivity to size of the wavepacket and the hierarchy. We find that wavepacket effects are relevant for the hierarchy determination up to nearly two orders of magnitude above the current experimental lower limit on the size, noting that there is no theoretical consensus on the expectation of this value. We also consider the effect in the context of other aspects of JUNO's nominal three-neutrino oscillation measurement physics program and the prospect of future enhancements to sensitivity, including from precise measurements of $\Delta m_{3l}^2$ and a near detector.

    hep-phPRD(2022)·15 citations
27. 27*

    New physics contributions to moments of inclusive $b\to c$ semileptonic decays

    Matteo Fael🇩🇪 · Muslem Rahimi🇩🇪 · K. Keri Vos🇳🇱

    Inclusive semileptonic $B\to X_c\ell {\bar{\nu }}_{\ell }$ decays, where $\ell =\mu ,e$, are by now standard candles in the determination of the CKM element $|V_{cb}|$. These determinations rely on the heavy-quark expansion and use moments of decay spectra to extract the non-perturbative parameters directly from data under the standard model assumption. At the same time, new physics could influence the moments of the inclusive decay. In this paper, we compute power-corrections and next-to-leading order corrections in the strong coupling constant using the full basis of dimension-six new physics operators for the inclusive $B\to X_c\ell \bar{\nu }$ decay. We provide predictions for lepton energy, hadronic and leptonic invariant mass moments, and perform a phenomenological study to show the possible impact of new physics. Our results could be used to perform a global fit including new physics contributions.

    hep-phJHEP(2023)·11 citations
28. 28*

    Partial compositeness under precision scrutiny

    Haiying Cai🇰🇷 · Giacomo Cacciapaglia🇫🇷

    We revisit the impact of top partial compositeness on electroweak precision observables in the misaligned vacuum basis. We identify a new source for $S$ in the singlet mixing case, and for $S$-$T$ in the bi-doublet mixing, stemming from misalignment in the gauge couplings of the top partners. Hence, a positive shift in $T$ can be obtained in both cases, as preferred by the recent CDF measurement of the $W$ mass. These results, obtained for the minimal fundamental coset SU(4)/Sp(4), apply to any composite Higgs model with top partial compositeness.

    hep-phJHEP(2022)·6 citations
29. 29*

    Three-loop QCD corrections to the decay constant of $B_c$

    Feng Feng🇨🇳 · Yu Jia🇨🇳 · Zhewen Mo🇨🇳 · Jichen Pan🇨🇳 · Wen-Long Sang🇨🇳 · Jia-Yue Zhang🇨🇳

    Within the framework of nonrelativistic QCD (NRQCD) factorization, we compute the three-loop QCD corrections to the decay constant of $B_c$. We reconstruct the analytical expressions for the three-loop renormalization constant and the corresponding anomalous dimension affiliated with the pseudoscalar current composed of two different heavy flavors in NRQCD, which are functions of the ratio between the charm and bottom quark masses. Meanwhile, the short-distance coefficient is obtained with very high numerical accuracy. The three-loop QCD correction turns out to be overwhelmingly large. The phenomenological implication of this new piece of radiative corrections for the $B_c$ leptonic decay is also addressed.

    hep-phhep-ex11 citations
30. 30*

    Magnetohydrodynamics predicts heavy-tailed distributions of axion-photon conversion

    Pierluca Carenza🇸🇪 · Ramkishor Sharma🇸🇪 · M.C. David Marsh🇸🇪 · Axel Brandenburg🇸🇪 · Eike Ravensburg🇸🇪

    The interconversion of axionlike particles (ALPs) and photons in magnetised astrophysical environments provides a promising route to search for ALPs. The strongest limits to date on light ALPs use galaxy clusters as ALP-photon converters. However, such studies traditionally rely on simple models of the cluster magnetic fields, with the state-of-the-art being Gaussian random fields (GRFs). We present the first systematic study of ALP-photon conversion in more realistic, turbulent fields from dedicated magnetohydrodynamic (MHD) simulations, which we compare with GRF models. For GRFs, we analytically derive the distribution of conversion ratios at fixed energy and find that it follows an exponential law. We find that the MHD models agree with the exponential law for typical, small-amplitude mixings but exhibit distinctly heavy tails for rare and large mixings. We explain how non-Gaussian features, e.g.~coherent structures and local spikes in the MHD magnetic field, are responsible for the heavy tail. Our results suggest that limits placed on ALPs using GRFs are robust.

    hep-phastro-ph.HEPRD(2023)·13 citations
31. 31*

    Bounds on ultralight bosons from the Event Horizon Telescope observation of Sgr A${}^{\ast }$

    Akash Kumar Saha🇮🇳 · Priyank Parashari🇮🇳 · Tarak Nath Maity🇮🇳 · Abhishek Dubey🇮🇳 · Subhadip Bouri🇮🇳 · Ranjan Laha🇮🇳

    Recent observation of Sagittarius A${}^{\ast }$ (Sgr A${}^{\ast }$) by the Event Horizon Telescope (EHT) collaboration has uncovered various unanswered questions in black hole (BH) physics. Besides, it may also probe various beyond the Standard Model (BSM) scenarios. One of the most profound possibilities is the search for ultralight bosons (ULBs) using BH superradiance (SR). EHT observations imply that Sgr A${}^{\ast }$ has a non-zero spin. Using this observation, we derive bounds on the mass of ULBs with purely gravitational interactions. Considering self-interacting ultralight axions, we constrain new regions in the parameter space of decay constant, for a certain spin of Sgr A${}^{\ast }$. Future observations of various spinning BHs can improve the present constraints on ULBs.

    ↳ astro-ph.HEastro-ph.COgr-qchep-ph+1EPJC(2024)·24 citations
32. 32*

    The Nielsen identities in screened theories

    Fabio Siringo🇮🇹 · Giorgio Comitini🇮🇹

    One-loop explicit expressions are derived for the gluon Nielsen identity in the formalism of the screened massive expansion for Yang-Mills theory. The gauge-parameter-independence of the poles and residues is discussed in a strict perturbative context and, more generally, in extended resummation schemes. No exact formal proof was reached by the approximate resummation schemes, but some evidence is gathered in favor of an exact invariance of the phase, consistently with previous numerical studies.

    ↳ hep-thhep-lathep-phPRD(2022)·8 citations
33. 33*

    Constraints on the axial-vector and pseudo-scalar mediated WIMP-nucleus interactions from PandaX-4T experiment

    Zhou Huang · Chencheng Han · Abdusalam Abdukerim · Zihao Bo · Wei Chen · Xun Chen · Yunhua Chen · Chen Cheng · Zhaokan Cheng · Xiangyi Cui · Yingjie Fan · Deqing Fang and 79 other authors

    We present the constraints on the axial-vector and pseudo-scalar mediated WIMP-nucleus interactions from the PandaX-4T experiment, using the data set corresponding to a total exposure of 0.63~tonne$\cdot$year. No significant signal excess is observed, and the most stringent upper limits to date on the spin-dependent WIMP-neutron scattering cross section are set at 90\% confidence level with the minimum WIMP-neutron scattering cross section of 5.8$\times 10^{-42}$\si{\cm^{2}} for WIMP mass of 40~\si{\GeV/}$c^2$. Exclusion limits on the axial-vector and pseudo-scalar simplified models are also derived.

    ↳ hep-exhep-phPLB(2022)·25 citations
34. 34*

    Weinberg operator contribution to the CP-odd nuclear force in the quark model

    Nodoka Yamanaka🇯🇵 · Makoto Oka🇯🇵

    The contribution of the CP violating three-gluon interaction, proposed by Weinberg, to the short-range CP-odd nuclear force is evaluated in the nonrelativistic quark model. We first show that the naive leading contribution generated by the quark exchange process vanishes at sufficiently short distance within the resonating group method, by considering the one-loop level gluon exchange CP-odd interquark potential induced by the Weinberg operator with massive quarks and gluons. We then estimate the true leading contribution by evaluating the gluonic correction to the CP-odd interquark potential in the closure approximation. It is found that the resulting irreducible CP-odd nuclear force is comparable to that generated by the chiral rotation of the CP-even short-range nuclear force, where the CP-odd mass calculated with QCD sum rules is used as input. The explicit calculation of the electric dipole moment (EDM) of the ${}^3$He nucleus yields $d_{{}^3\mathrm{He}}^{(\mathrm{irr})}(w)=-1.5we$ MeV. The total ${}^3$He EDM, accounting for the intrinsic nucleon EDM, the pion-exchange and the short-range CP-odd nuclear force, is $d_{{}^3\mathrm{He}}^{(\mathrm{tot})}(w)=20_{-11}^{+14}we$ MeV, with the dominant effect coming from the intrinsic nucleon EDM.

    ↳ nucl-thhep-exhep-phnucl-exPRD(2022)·7 citations
35. 35*

    Confinement in non-Abelian lattice gauge theory via persistent homology

    Daniel Spitz🇩🇪 · Julian M. Urban🇩🇪 · Jan M. Pawlowski🇩🇪

    We investigate the structure of confining and deconfining phases in SU(2) lattice gauge theory via persistent homology, which gives us access to the topology of a hierarchy of combinatorial objects constructed from given data. Specifically, we use filtrations by traced Polyakov loops, topological densities, holonomy Lie algebra fields, as well as electric and magnetic fields. This allows for a comprehensive picture of confinement. In particular, topological densities form spatial lumps which show signatures of the classical probability distribution of instanton-dyons. Signatures of well-separated dyons located at random positions are encoded in holonomy Lie algebra fields, following the semi-classical temperature dependence of the instanton appearance probability. Debye screening discriminating between electric and magnetic fields is visible in persistent homology and pronounced at large gauge coupling. All employed constructions are gauge-invariant without a priori assumptions on the configurations under study. This work showcases the versatility of persistent homology for statistical and quantum physics studies, barely explored to date.

    ↳ hep-latcond-mat.stat-mechhep-phhep-th+1PRD(2023)·17 citations
36. 36*

    Precision calculation of the recoil--finite-size correction for the hyperfine splitting in muonic and electronic hydrogen

    Aldo Antognini🇨🇭 · Yong-Hui Lin🇩🇪 · Ulf-G. Meißner🇩🇪

    We present a high-precision calculation of the recoil--finite-size correction to the hyperfine splitting (HFS) in muonic and electronic hydrogen based on nucleon electromagnetic form factors obtained from dispersion theory. This will help guide the upcoming searches of the HFS transition in muonic hydrogen, and will allow a precise determination of the polarizability and Zemach radius contributions when this transition is found.

    ↳ nucl-thhep-phphysics.atom-phPLB(2022)·16 citations
37. 37*

    Four-top quark physics at the LHC

    Freya Blekman🇩🇪 · Fréderic Déliot🇫🇷 · Valentina Dutta🇺🇸 · Emanuele Usai🇺🇸

    The production of four top quarks is a rare process in the Standard Model that provides unique opportunities and sensitivity to Standard Model observables including potential enhancement from many popular new physics extensions. This article summarises the latest experimental measurements of the four-top quark production cross section at the LHC. An overview of the interpretations of the experimental results in terms of the top quark Yukawa coupling and limits on physics beyond the Standard Model is also given as well as prospects for future measurements and opportunities offered by this challenging final state.

    ↳ hep-exhep-phUniverse(2022)·22 citations
38. 38*

    Non-invertible Time-reversal Symmetry

    Yichul Choi🇺🇸 · Ho Tat Lam🇺🇸 · Shu-Heng Shao🇺🇸

    In gauge theory, it is commonly stated that time-reversal symmetry only exists at $\theta =0$ or $\pi$ for a $2\pi$-periodic $\theta$-angle. In this paper, we point out that in both the free Maxwell theory and massive QED, there is a non-invertible time-reversal symmetry at every rational $\theta$-angle, i.e., $\theta =\pi p/N$. The non-invertible time-reversal symmetry is implemented by a conserved, anti-linear operator without an inverse. It is a composition of the naive time-reversal transformation and a fractional quantum Hall state. We also find similar non-invertible time-reversal symmetries in non-Abelian gauge theories, including the $\mathcal{N}=4$ $SU(2)$ super Yang-Mills theory along the locus $|\tau |=1$ on the conformal manifold.

    ↳ hep-thcond-mat.str-elhep-phPRL(2023)·132 citations
39. 39*

    An Effective Field Theory for Large Oscillons

    D. G. Levkov🇷🇺 · V. E. Maslov🇷🇺 · E. Ya. Nugaev🇷🇺 · A. G. Panin🇷🇺

    We consider oscillons - localized, quasiperiodic, and extremely long-living classical solutions in models with real scalar fields. We develop their effective description in the limit of large size at finite field strength. Namely, we note that nonlinear long-range field configurations can be described by an effective complex field $\psi (t,\mathbf{x})$ which is related to the original fields by a canonical transformation. The action for $\psi$ has the form of a systematic gradient expansion. At every order of the expansion, such an effective theory has a global U(1) symmetry and hence a family of stationary nontopological solitons - oscillons. The decay of the latter objects is a nonperturbative process from the viewpoint of the effective theory. Our approach gives an intuitive understanding of oscillons in full nonlinearity and explains their longevity. Importantly, it also provides reliable selection criteria for models with long-lived oscillons. This technique is more precise in the nonrelativistic limit, in the notable cases of nonlinear, extremely long-lived, and large objects, and also in lower spatial dimensions. We test the effective theory by performing explicit numerical simulations of a $(d+1)$-dimensional scalar field with a plateau potential.

    ↳ hep-thastro-ph.COhep-phJHEP(2022)·20 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.