Thu·Nov 11, 2021Thursday·November 11, 2021

1. 01*

   QED Parton Distribution Functions in the MSHT20 Fit

   T. Cridge🇬🇧 · L. A. Harland-Lang🇬🇧 · A. D. Martin🇬🇧 · R.S. Thorne🇬🇧

   We present the MSHT20qed set of parton distribution functions (PDFs). These are obtained from the MSHT20 global analysis via a refit including QED corrections to the DGLAP evolution at $\mathcal{O}(\alpha ),\mathcal{O}(\alpha {\alpha }_S)$ and $\mathcal{O}({\alpha }^2)$, and containing the photon PDF of the proton. As in the previous MMHT15qed study we use an input distribution for the photon that is derived from the LUXqed formulation, and find good consistency for the photon PDF with that of MMHT15qed, as well as with other recent sets. We also present a set of QED corrected neutron PDFs and accompanying photon distribution, and provide the photon PDF of the nucleons separated into elastic and inelastic contributions. We assess the general expectations for the impact of photon-initiated (PI) corrections to processes entering PDF fits, and review the effect of QED corrections on the other partons and on the fit quality, where electroweak corrections (including PI production) are appropriately added to the cross sections wherever possible. We explore the phenomenological implications of this set by comparing to a variety of benchmark cross sections, finding small but significant corrections due to the inclusion of QED effects in the PDFs.

   hep-phhep-exEPJC(2022)·68 citations
2. 02*

   Light-nuclei gluons from dijet production in proton-oxygen collisions

   Petja Paakkinen🇫🇮

   The prospects of measuring a single-differential dijet cross section during the proposed short proton-oxygen data taking at LHC Run 3 are studied using next-to-leading-order perturbative QCD predictions. With reasonable experimental cuts and luminosity estimates, such a measurement is found to be feasible, and a few inverse nanobarns of integrated luminosity is estimated to be enough to yield new constraints on parton distribution functions (PDFs) of light nuclei. In the absence of a dedicated proton-proton reference, a mixed-energy nuclear modification ratio is proposed for cancelling free-proton PDF uncertainties to obtain a direct access to the nuclear modifications of the parton distributions in oxygen.

   hep-phPRD(2022)·18 citations
3. 03*

   A method to challenge symmetries in data with self-supervised learning

   Rupert Tombs🇬🇧 · Christopher G. Lester🇬🇧

   Symmetries are key properties of physical models and of experimental designs, but any proposed symmetry may or may not be realized in nature. In this paper, we introduce a practical and general method to test such suspected symmetries in data, with minimal external input. Self-supervision, which derives learning objectives from data without external labelling, is used to train models to predict 'which is real?' between real data and symmetrically transformed alternatives. If these models make successful predictions in independent tests, then they challenge the targeted symmetries. Crucially, our method handles filtered data, which often arise from inefficiencies or deliberate selections, and which could give the illusion of asymmetry if mistreated. We use examples to demonstrate how the method works and how the models' predictions can be interpreted. Code and data are available at https://zenodo.org/record/6861702.

   hep-phphysics.data-anJINST(2022)·35 citations
4. 04*

   Non-unitarity and sterile neutrinos at the DUNE near detector

   Salvador Urrea🇪🇸

   We study the capabilities of the DUNE near detector to probe the 3+1 sterile formalism and the non-unitarity of the leptonic sector. We add to the current analyses in the literature, the use of the charged current events for the ${\nu }_{\tau }$ appearance channel and the consideration of the energy spectral uncertainty (shape uncertainty) for the different channels which plays an important role, especially at the near detector, and has been usually overlooked in the literature. We find that even with this more conservative and realistic approach, we still obtain an improvement in the sensitivity with respect to the current bounds.

   hep-phJ.Phys.Conf.Ser.(2021)·0 citations
5. 05*

   Flavor and CP Violation from a QCD-like Hidden Sector

   Wafia Bensalem🇨🇦 · Daniel Stolarski🇨🇦

   Confining hidden sectors at the GeV scale are well motivated by asymmetric dark matter and naturalness considerations and can also give interesting collider signatures. Here we study such sectors connected to the Standard Model by a TeV scale mediator charged under both QCD and the dark force. Such a mediator admits a Yukawa coupling between quarks and dark quarks which is generically flavour and $CP$ violating. We show that in contrast to expectation, electric dipole moments do not place a strong constraint on this scenario even with $O(1)$ $CP$-violating phases. We also quantitatively explore constraints from $\Delta F=1,2$ processes as a function of the number of dark quark flavours. Finally, we describe the reach of upcoming measurements at Belle-II and KOTO, and we propose new $CP$-odd observables in rare meson decays that may be sensitive to the $CP$-violating nature of the dark sector.

   hep-phJHEP(2022)·8 citations
6. 06*

   Production and attenuation of cosmic-ray boosted dark matter

   Chen Xia🇨🇳 · Yan-Hao Xu🇨🇳 · Yu-Feng Zhou🇨🇳

   Light sub-GeV halo dark matter (DM) particles up-scattered by high-energy cosmic-rays (CRs) (referred to as CRDM) can be energetic and become detectable by conventional DM direct detection experiments. We perform a refined analysis on the exclusion bounds of the spin-independent DM-nucleon scattering cross section ${\sigma }_{\chi p}$ in this approach. For the exclusion lower bounds, we determine the parameter of the effective distance $D_{\text{eff}}$ for CRDM production using spatial-dependent CR fluxes and including the contributions from the major heavy CR nuclear species. We obtain $D_{\text{eff}}\simeq 9$ kpc for CRDM particles with kinetic energy above $\sim 1\text{GeV}$, which pushes the corresponding exclusion lower bounds down to ${\sigma }_{\chi p}\sim 4\times 10^{-32}{\text{cm}}^2$ for DM particle mass at MeV scale and below. For the exclusion upper bounds from Earth attenuation, previous estimations neglecting the nuclear form factor leaded to typical exclusion upper bounds of ${\sigma }_{\chi p}\sim \mathcal{O}(10^{-28}){\text{cm}}^2$ from the XENON1T data. Using both the analytic and numerical approaches, we show that for CRDM particles, the presence of the nuclear form factor strongly suppresses the effect of Earth attenuation. Consequently, the cross section that can be excluded by the XENON1T data can be a few orders of magnitude higher, which closes the gap in the cross sections excluded by the XENON1T experiment and that by the astrophysical measurements such that for the cosmic microwave background (CMB), galactic gas cloud cooling, and structure formation, etc..

   hep-phJCAP(2022)·79 citations
7. 07*

   Unpolarized DIS structure functions in Double-Logarithmic Approximation

   B.I. Ermolaev🇷🇺 · S.I. Troyan🇷🇺

   We present description of the DIS structure functions F_1 and F_2 at small $x$ obtained in double-logarithmic approximation (DLA). First we clarify our previous results on F_1 and then obtain explicit expressions for F_2. Our calculations confirm our previous result that the small-$x$ asymptotics of F_1 is controlled by a new Pomeron that has nothing to do with the BFKL Pomeron, though their intercepts are pretty close. The latter means that studying the small-x dependence of the unpolarized DIS cannot ascertain which of those Pomerons is actually involved. However, we predict a quite different and universal Q^2-dependence of F_1,F_2 in DLA compared to the approaches involving the both DGLAP and BFKL. On that basis, we construct simple relations between logarithms of F_1, F_2, which can be verified with analysis of experimental data. In contrast to F_1, the intercept controlling the small-x asymptotics of F_2 is very small but positive, which ensures growth of F_2 at small x.

   hep-phhep-ex0 citations
8. 08*

   Production cross sections of tetraquark states in elementary hadronic collisions

   Gábor Balassa🇭🇺 · György Wolf🇭🇺

   Inclusive production cross sections of the possible exotic state X(3872) in proton-proton, pionp-roton and proton-antiproton collisions are calculated using a statistical based model, which is previously used to describe inclusive charmed and bottomed hadron production cross sections in the low energy region. With the extensions made here, the model is capable to include tetraquarks as well, using the diquark picture of tetraquarks. The evaluated cross section ratio of $\Psi (2S)$ and $X(3872)$ at $\sqrt{s}=7$ TeV agrees well with the measured value.

   hep-phEPJA(2021)·6 citations
9. 09*

   Signals of $W^{\prime }$ and $Z^{\prime }$ bosons at the LHC in the $SU(3)\times SO(5)\times U(1)$ gauge-Higgs unification

   Shuichiro Funatsu🇨🇳 · Hisaki Hatanaka🇯🇵 · Yutaka Hosotani🇯🇵 · Yuta Orikasa🇨🇿 · Naoki Yamatsu🇯🇵

   The $pp\to \{W,W^{\prime }\}\to l\nu$ and $pp\to \{\gamma ,Z,Z^{\prime }\}\to l^{+}{l}^{-}$ ($l=e,\mu$) processes in the $SU(3{)}_C\times SO(5)\times U(1{)}_X$ gauge-Higgs unification (GHU) models are studied, where $W^{\prime }$ and $Z^{\prime }$ bosons are Kaluza-Klein (KK) exited states of the electroweak gauge bosons. From the experimental data collected at the Large Hadron Collider, constraints on the KK mass scale and the Aharonov-Bohm phase are obtained. One can explore the KK mass scale in the GUT inspired GHU model up to 18 TeV for the luminosity 300 fb${}^{-1}$ and 22 TeV for the luminosity 3000 fb${}^{-1}$ at $\sqrt{s}=14$ TeV.

   hep-phPRD(2022)·11 citations
10. 10*

    Constraints on ultralight axions, vector gauge bosons, and unparticles from geodetic and frame-dragging measurements

    Tanmay Kumar Poddar🇮🇳

    The geodetic and frame-dragging effects are the direct consequences of the spacetime curvature near Earth which can be probed from the Gravity probe B (GP-B) satellite. The satellite result matches quite well with Einstein's general relativistic result. The gyroscope of the satellite which measures the spacetime curvature near Earth contains lots of electrons and nucleons. Ultralight axions, vector gauge bosons, and unparticles can interact with these electrons and nucleons through different spin-dependent and spin-independent operators and change the drift rate of the gyroscope. Some of these ultralight particles can either behave as a long range force between some dark sector or Earth and the gyroscope or they can behave as a background oscillating dark matter fields or both. These ultralight particles can contribute an additional precession of the gyroscopes, limited to be no larger than the uncertainty in the GP-B measurements. Compared with the experimental results, we obtain bounds on different operator couplings.

    hep-phastro-ph.COgr-qcEPJC(2022)·15 citations
11. 11*

    Resonance contributions in $B^{-}\to K^{+}{K}^{-}{\pi }^{-}$ within the light-come sum rule approach

    Yu-Ji Shi🇩🇪 · Ulf-G. Meißner🇩🇪 · Zhen-Xing Zhao🇨🇳

    In this work, we study the resonance contributions to the decay $B^{-}\to K^{+}{K}^{-}{\pi }^{-}$, which is dominated by the scalar $f_0(980),K_0^{\ast }(1430)$, vector $\rho (1450),\varphi (1020),K^{\ast }(892)$ and tensor $f_2(1270)$ resonances. The three-body decay is reduced to various quasi two-body decays, where the $B$ meson firstly decays into a resonance and a pion or a kaon, subsequently the resonance decays into the other two final-state mesons. The quasi two-body decays are calculated within the light-cone sum rule approach utilizing the leading twist $B$ meson light-cone distribution amplitudes. Finally, the decay branching fraction contribution from each resonance are calculated. Some of them are compatible with experiment or previous theoretical works. Including the effects of non-resonant and final-state interactions, we also evaluate the total branching fraction.

    hep-phhep-exEPJC(2022)·6 citations
12. 12*

    Quantum gravity phenomenology at the dawn of the multi-messenger era -- A review

    A. Addazi · J. Alvarez-Muniz · R. Alves Batista · G. Amelino-Camelia · V. Antonelli · M. Arzano · M. Asorey · J.-L. Atteia · S. Bahamonde · F. Bajardi · A. Ballesteros · B. Baret and 148 other authors

    The exploration of the universe has recently entered a new era thanks to the multi-messenger paradigm, characterized by a continuous increase in the quantity and quality of experimental data that is obtained by the detection of the various cosmic messengers (photons, neutrinos, cosmic rays and gravitational waves) from numerous origins. They give us information about their sources in the universe and the properties of the intergalactic medium. Moreover, multi-messenger astronomy opens up the possibility to search for phenomenological signatures of quantum gravity. On the one hand, the most energetic events allow us to test our physical theories at energy regimes which are not directly accessible in accelerators; on the other hand, tiny effects in the propagation of very high energy particles could be amplified by cosmological distances. After decades of merely theoretical investigations, the possibility of obtaining phenomenological indications of Planck-scale effects is a revolutionary step in the quest for a quantum theory of gravity, but it requires cooperation between different communities of physicists (both theoretical and experimental). This review is aimed at promoting this cooperation by giving a state-of-the art account of the interdisciplinary expertise that is needed in the effective search of quantum gravity footprints in the production, propagation and detection of cosmic messengers.

    hep-phastro-ph.HEgr-qchep-thPPNP(2022)·606 citations
13. 13*

    Constraints on the dark photon from deep inelastic scattering

    A. W. Thomas🇦🇺 · X. G. Wang🇦🇺 · A. G. Williams🇦🇺

    We investigate constraints on the dark photon arising from an analysis of deep inelastic scattering (DIS) data. We perform extractions of parton distribution functions (PDFs) with and without a dark photon being present and allow the dark photon mixing parameter and mass to vary. We also include the effects of vector meson dominance to ensure the correct photo-production limit. By considering the variation of the total ${\chi }^2$ arising from such extractions we infer exclusion limits on the kinetic mixing parameter of the dark photon for dark photon mass up to $80\mathrm{GeV}$.

    hep-phhep-exPRD(2022)·27 citations
14. 14*

    Dark matter stability at fixed points in a modular $A_4$ symmetry

    Tatsuo Kobayashi🇯🇵 · Hiroshi Okada🇰🇷 · Yuta Orikasa🇨🇿

    We propose a new mechanism of stabilization for dark matter under fixed points of modular $A_4$ symmetry, thanks to recovering a residual symmetry for each of fixed points at $\tau =\omega ,i,i\times \infty$. We find that a model at $\tau =i$ successfully reproduces the neutrino oscillation data without conflict of the DM stability.

    hep-phPhys.Dark Univ.(2022)·27 citations
15. 15*

    Mechanism for baryogenesis via feebly interacting massive particles

    Andreas Goudelis🇫🇷 · Pantelis Papachristou🇬🇷 · Vassilis C. Spanos🇬🇷

    We present a simple mechanism which allows the simultaneous generation of the baryon asymmetry of the Universe along with its dark matter content. To this goal, we employ the out-of-equilibrium decays of heavy bath states into a feebly coupled dark matter particle and Standard Model charged fermions. These decays lead to dark matter production via the freeze-in mechanism and, assuming that they further violate $CP$, can generate a viable matter-antimatter asymmetry in the resonant regime. We illustrate this mechanism by studying a particular realization of this general scenario, where the role of the heavy bath particles is played by $SU(3{)}_{\text{c}}\times SU(2{)}_{\text{L}}$-singlet vectorlike fermions with a non-zero hypercharge and dark matter is identified with a gauge-singlet real scalar field. We show that in the context of this simple model the cosmological constraints for the dark matter abundance and the baryon asymmetry are satisfied for masses of heavy vectorlike fermion states of a few TeV, potentially within reach of the High-Luminosity Run of the Large Hadron Collider. Dark matter, in turn, is predicted to be rather light, with a mass of a few keV.

    hep-phPRD(2022)·15 citations
16. 16*

    Bayesian Approach to Inverse Problems: an Application to NNPDF Closure Testing

    Luigi Del Debbio🇬🇧 · Tommaso Giani🇳🇱 · Michael Wilson🇬🇧

    We discuss the Bayesian approach to the solution of inverse problems and apply the formalism to analyse the closure tests performed by the NNPDF collaboration. Starting from a comparison with the approach that is currently used for the determination of parton distributions (PDFs) by the NNPDF collaboration, we discuss some analytical results that can be obtained for linear problems and use these results as a guidance for the more complicated non-linear problems. We show that, in the case of Gaussian distributions, the posterior probability density of the parametrized PDFs is fully determined by the results of the NNPDF fitting procedure. In the particular case that we consider, the fitting procedure and the Bayesian analysis yield exactly the same result. Building on the insight that we obtain from the analytical results, we introduce new estimators to assess the statistical faithfulness of the fit results in closure tests. These estimators are defined in data space, and can be studied analytically using the Bayesian formalism in a linear model in order to clarify their meaning. Finally we present numerical results from a number of closure tests performed with current NNPDF methodologies. These further tests allow us to validate the NNPDF4.0 methodology and provide a quantitative comparison of the NNPDF4.0 and NNPDF3.1 methodologies. As PDFs determinations move into precision territory, the need for a careful validation of the methodology becomes increasingly important: the error bar has become the focal point of contemporary PDFs determinations. In this perspective, theoretical assumptions and other sources of error are best formulated and analysed in the Bayesian framework, which provides an ideal language to address the precision and the accuracy of current fits.

    hep-phEPJC(2022)·94 citations
17. 17*

    Sterile Neutrino Searches with MicroBooNE: Electron Neutrino Disappearance

    Peter B. Denton🇺🇸

    A sterile neutrino is a well motivated minimal new physics model that leaves an imprint in neutrino oscillations. Over the last two decades, a number of hints pointing to a sterile neutrino have emerged, many of which are pointing near $m_4\sim 1$ eV. Here we show how MicroBooNE data can be used to search for electron neutrino disappearance using each of their four analysis channels. We find a hint for oscillations with the highest single channel significance of $2.4\sigma$ (using the Feldman-Cousins approach) coming from the Wire-Cell analysis and a simplified treatment of the experimental systematics. The preferred parameters are ${\sin }^2(2{\theta }_{14})=0.35_{-0.16}^{+0.19}$ and $\Delta m_{41}^2=1.25_{-0.39}^{+0.74}$ eV${}^2$. This region of parameter space is in good agreement with existing hints from source experiments, is at a similar frequency but higher mixing than indicated by reactor anti-neutrinos, and is at the edge of the region allowed by solar neutrino data. Existing unanalyzed data from MicroBooNE could increase the sensitivity to the $>3\sigma$ level.

    hep-phhep-exPRL(2022)·63 citations
18. 18*

    Chirality production during axion inflation

    E.V. Gorbar · A.I. Momot · I.V. Rudenok · O.O. Sobol · S.I. Vilchinskii

    We study the generation of the chiral charge during axion inflation where the pseudoscalar inflaton field $\varphi$ couples axially to the electromagnetic field through the term $(\beta /M_p)\varphi \mathbf{E}\cdot \mathbf{B}$ with dimensionless coupling constant $\beta$. To describe the evolution of electromagnetic field and determine $⟨\mathbf{E}\cdot \mathbf{B}⟩$ sourcing the chiral asymmetry during inflation due to the chiral anomaly, we employ the gradient expansion formalism. It operates with a set of vacuum expectation values of bilinear electromagnetic functions and allows us to take into account the backreaction of generated fields on the inflaton evolution as well as the Schwinger production of charged fermions. In addition, we include the chiral magnetic effect contribution to the electric current ${\mathbf{j}}_{\mathrm{CME}}=e^2/(2{\pi }^2){\mu }_5\mathbf{B}$, where ${\mu }_5$ is the chiral chemical potential which quantifies the chiral charge production. Solving a set of equations for the inflaton field, scale factor, quadratic functions of the electromagnetic field, and the chiral charge density (chiral chemical potential), we find that the chirality production is quite efficient leading to the generation of a large chemical potential at the end of axion inflation.

    hep-phastro-ph.COhep-thUkr.J.Phys.(2023)·14 citations
19. 19*

    Light scalars in neutron star mergers

    P. S. Bhupal Dev🇺🇸 · Jean-François Fortin🇨🇦 · Steven P. Harris🇺🇸 · Kuver Sinha🇺🇸 · Yongchao Zhang🇨🇳

    Due to their unique set of multimessenger signals, neutron star mergers have emerged as a novel environment for studies of new physics beyond the Standard Model (SM). As a case study, we consider the simplest extension of the SM scalar sector involving a light CP-even scalar singlet $S$ mixing with the SM Higgs boson. These $S$ particles can be produced abundantly in neutron star mergers via the nucleon bremsstrahlung process. We show that the $S$ particles may either be trapped in or stream freely out of the merger remnant, depending on the $S$ mass, its mixing with the SM Higgs boson, and the temperature and baryon density in the merger. In the free-streaming region, the scalar $S$ will provide an extra channel to cool down the merger remnant, with cooling timescales as small as $\mathcal{O}$(ms). On the other hand, in the trapped region, the Bose gas of $S$ particles could contribute a larger thermal conductivity than the trapped neutrinos in some parts of the parameter space, thus leading to faster thermal equilibration than expected. Therefore, future observations of the early postmerger phase of a neutron star merger could effectively probe a unique range of the $S$ parameter space, largely complementary to the existing and future laboratory and supernova limits. In view of these results, we hope the merger simulation community will be motivated to implement the effects of light CP-even scalars into their simulations in both the free-streaming and trapped regimes.

    hep-phastro-ph.HEnucl-thJCAP(2022)·18 citations
20. 20*

    Probing Neutrino-Portal Dark Matter at the Forward Physics Facility

    Kevin J. Kelly🇺🇸 · Felix Kling🇩🇪 · Douglas Tuckler🇨🇦 · Yue Zhang🇨🇦

    The Forward Physics Facility (FPF), planned to operate near the ATLAS interaction point at the LHC, offers exciting new terrain to explore neutrino properties at TeV energy scales. It will reach an unprecedented regime for terrestrial neutrino experiments and provide the opportunity to reveal new physics of neutrinos at higher energy scales. We demonstrate that future detectors at the FPF have the potential to discover new mediators that couple predominantly to neutrinos, with masses between 0.3 and 20 GeV and small couplings not yet probed by existing searches. Such a neutrinophilic mediator is well motivated for addressing the origin of several neutrino-portal dark matter candidates, including thermal freeze-out and sterile-neutrino dark matter scenarios. Experimentally, the corresponding signatures include neutrino charged-current scattering events associated with large missing transverse momentum, and excessive apparent tau-neutrino events. We discuss the FPF detector capabilities needed for this search, most importantly the hadronic energy resolution.

    hep-phhep-exPRD(2022)·42 citations
21. 21*

    Effective limits on single scalar extensions in the light of recent LHC data

    Anisha🇮🇳 · Supratim Das Bakshi🇮🇳 · Shankha Banerjee🇨🇭 · Anke Biekötter🇬🇧 · Joydeep Chakrabortty🇮🇳 · Sunando Kumar Patra🇮🇳 · Michael Spannowsky🇬🇧

    In this paper, we work with 16 different single scalar particle extensions of the Standard Model. We present the sets of dimension-6 effective operators and the associated Wilson coefficients as functions of model parameters after integrating out the heavy scalars up to 1-loop, including the heavy-light mixing, for each such scenario. Using the correspondence between the effective operators and the observables at electroweak scale, and employing Bayesian statistics, we compute the allowed ranges of new physics parameters that are further translated and depicted in 2-dimensional Wilson coefficient space in the light of the latest CMS and ATLAS data up to $137{\text{ fb}}^{-1}$ and $139{\text{ fb}}^{-1}$, respectively. We also adjudge the status of those new physics extensions that offer similar sets of relevant effective operators. In addition, we provide a model-independent fit of $23$ Standard Model effective field theory Wilson coefficients using electroweak precision observables, single and di-Higgs data as well as kinematic distributions of di-boson production.

    hep-phhep-exhep-thPRD(2023)·48 citations
22. 22*

    Scalable Qubit Representations of Neutrino Mixing Matrices

    M.J. Molewski🇺🇸 · B.J.P. Jones🇺🇸

    Oscillating neutrino beams exhibit quantum coherence over distances of thousands of kilometers. Their unambiguously quantum nature suggests an appealing test system for direct quantum simulation. Such techniques may enable presently analytically intractable calculations involving multi-neutrino entanglements, such as collective neutrino oscillations in supernovae, but only once oscillation phenomenology is properly re-expressed in the language of quantum circuits. Here we resolve outstanding conceptual issues regarding encoding of arbitrarily mixed neutrino flavor states in the Hilbert space of an n-qubit quantum computer. We introduce algorithms to encode mixing and oscillation of any number of flavor-mixed neutrinos, both with and without CP-violation, with an efficient number of prescriptive input parameters in terms of sub-rotations of the PMNS matrix in standard form. Examples encoded for an IBM-Q quantum computer are shown to converge to analytic predictions both with and without CP-violation.

    ↳ quant-phhep-exhep-phPRD(2022)·17 citations
23. 23*

    Nonmetricity theories and aspects of gauge symmetry

    Israel Quiros🇲🇽

    In this paper we discuss on the phenomenological viability of nonmetricity theories of gravity which are based in the class of generalized Weyl spacetimes -- denoted by $W_4$ -- where arbitrary nonmetricity is allowed. This class of geometry includes the so called teleparallel spaces $Z_4$, which are the geometric basement of the symmetric teleparallel theories (STTs). The guiding principle in our discussion is Weyl gauge symmetry (WGS), which is a manifest symmetry of $W_4$ spaces. Here we derive the master equation that drives the gauge invariant variations of the length of vectors during parallel transport in $W_4$. This is the mathematical basis of the second clock effect (SCE). We are able to give qualitative and quantitative estimates for the SCE, as well as for the perihelion shift, in the coincident gauge of $Z_4$ space. We conclude that generalized Weyl spaces do not represent phenomenologically viable descriptions of Nature due to the SCE and, also to their predictions for the perihelion shift. All of the present results are based in the assumption of: (i) a gauge invariant parallel transport law and (ii) a consistency hypothesis which enables identifying hypothetical vectors and tensors defined in $W_4$, with related physical vectors and tensors arising in the given gravitational theory. Our discussion is mostly geometrical without relying on specific theories of gravity, unless it is absolutely necessary.

    ↳ gr-qchep-phPRD(2022)·38 citations
24. 24*

    Particle physics facing a pandemic

    Adam Kardos🇭🇺 · Sven-Olaf Moch🇩🇪 · German Rodrigo🇪🇸

    Our ordinary life changed quite a bit in March of 2020 due to the global Covid-19 pandemic. While spring time in general well awaited and regarded as a synonym for rejuvenation the spring of 2020 brought lock-down, curfew, home office and digital education to the lives of many. The particle physics community was not an exception: research institutes and universities introduced home office and digital lecturing and all workshops, conferences and summer schools were canceled, got postponed or took place online. Using publicly available data from the INSPIRE and arXiv databases we investigate the effects of this dramatic change of life to the publishing trends of the high-energy physics community with an emphasis on particle phenomenology and theory. To get insights we gather information about publishing trends in the last 20 years, and analyse it in detail.

    ↳ physics.soc-phhep-exhep-phhep-thOpen Res Europe(2023)·0 citations
25. 25*

    Tree-level unitarity in Higgs inflation in the metric and the Palatini formulation

    Asuka Ito🇹🇼 · Wafaa Khater🇵🇸 · Syksy Rasanen🇫🇮

    We calculate the tree-level amplitudes for electrically neutral $2\to 2$ scattering for the Standard Model Higgs doublet non-minimally coupled to the Ricci scalar. We consider both the metric and the Palatini formulation of gravity. We find the partial wave unitarity limit for a general background field value. Our results are in agreement with previous work. In the electroweak vacuum, tree-level unitarity is violated at $\sim M_{\text{Planck}}/\xi$ in the metric formulation, and at $\sim M_{\text{Planck}}/\sqrt{\xi }$ in the Palatini formulation. In the inflationary large field background, the unitarity limit is at $\sim M_{\text{Planck}}/\sqrt{\xi }$ in both formulations. We compare the unitarity violation energy to scales relevant during inflation. We also calculate a direct collider limit on $\xi$ in the Palatini formulation, $\xi <2.5\times 10^{31}$.

    ↳ astro-ph.COgr-qchep-phhep-thJHEP(2022)·37 citations
26. 26*

    New scenario of QCD axion clump formation I: Linear analysis

    Naoya Kitajima🇯🇵 · Kazuhiro Kogai🇯🇵 · Yuko Urakawa🇯🇵

    The QCD axion acquires the potential through the non-perturbative effect of the QCD matters around the QCD phase transition. During this period, the direct interaction between the axion and the QCD matters sets in. Focusing on the impact of this direct interaction, we propose two scenarios where the fluctuation of the axion can rapidly grow, potentially leading to the formation of axion miniclusters even if the Peccei-Quinn (PQ) symmetry was already broken during inflation. The first scenario assumes that the primordial curvature perturbation at the horizon scale during the QCD epoch was significantly enhanced and the second one assumes that the initial misalignment was tuned around the hilltop of the potential.

    ↳ astro-ph.COgr-qchep-phhep-thJCAP(2022)·13 citations
27. 27*

    Science Case for the new High-Intensity Muon Beams HIMB at PSI

    M. Aiba🇨🇭 · A. Amato🇨🇭 · A. Antognini🇨🇭 · S. Ban🇯🇵 · N. Berger🇩🇪 · L. Caminada🇨🇭 · R. Chislett🇬🇧 · P. Crivelli🇨🇭 · A. Crivellin🇨🇭 · G. Dal Maso🇨🇭 · S. Davidson🇫🇷 · M. Hoferichter🇨🇭 and 24 other authors

    In April 2021, scientists active in muon physics met to discuss and work out the physics case for the new High-Intensity Muon Beams (HIMB) project at PSI that could deliver of order $10^{10}$\,s${}^{-1}$ surface muons to experiments. Ideas and concrete proposals were further substantiated over the following months and assembled in the present document. The high intensities will allow for completely new experiments with considerable discovery potential and unique sensitivities. The physics case is outstanding and extremely rich, ranging from fundamental particle physics via chemistry to condensed matter research and applications in energy research and elemental analysis. In all these fields, HIMB will ensure that the facilities S$\mu$S and CHRISP on PSI's High Intensity Proton Accelerator complex HIPA remain world-leading, despite the competition of muon facilities elsewhere.

    ↳ hep-excond-mat.mtrl-scihep-ph82 citations
28. 28*

    Utilizing cosmic-ray positron and electron observations to probe the averaged properties of Milky Way pulsars

    Ilias Cholis🇺🇸 · Iason Krommydas🇬🇷

    Pulsars have long been studied in the electromagnetic spectrum. Their environments are rich in high-energy cosmic-ray electrons and positrons likely enriching the interstellar medium with such particles. In this work we use recent cosmic-ray observations from the AMS-02, CALET and DAMPE collaborations to study the averaged properties of the local Milky Way pulsar population. We perform simulations of the local Milky Way pulsar population, for interstellar medium assumptions in agreement with a range of cosmic-ray nuclei measurements. Each such simulation contains $\sim 10^4$ pulsars of unique age, location, initial spin-down power and cosmic-ray electron/positron spectra. We produce more than $7\times 10^3$ such Milky Way pulsar simulations. We account for and study i) the pulsars' birth rates and the stochastic nature of their birth, ii) their initial spin-down power distribution, iii) their time evolution in terms of their braking index and characteristic spin-down timescale, iv) the fraction of spin-down power going to cosmic-ray electrons and positrons and v) their propagation through the interstellar medium and the Heliosphere. We find that pulsars of ages $\sim 10^5-10^7$ yr, have a braking index that on average has to be 3 or larger. Given that electromagnetic spectrum observations of young pulsars find braking indices lower than 3, our work provides strong hints that pulsars' braking index increases on average as they age, allowing them to retain some of their rotational energy. Moreover, we find that pulsars have relatively uniform properties as sources of cosmic-ray electrons and positrons in terms of the spectra they produce and likely release O($10\%$) of their rotational energy to cosmic-rays in the ISM. Finally, we find at $\simeq$12 GeV positrons a spectral feature that suggests a new subpopulation of positron sources contributing at these energies.

    ↳ astro-ph.HEhep-phPRD(2022)·23 citations
29. 29*

    Natural evidence for fuzzy sphere noncommutative geometry: super-Chandrasekhar white dwarfs

    Surajit Kalita🇮🇳 · T. R. Govindarajan🇮🇳 · Banibrata Mukhopadhyay🇮🇳

    Noncommutative geometry is one of the quantum gravity theories, which various researchers have been using to describe different physical and astrophysical systems. However, so far, no direct observations can justify its existence, and this theory remains a hypothesis. On the other hand, over the past two decades, more than a dozen over-luminous type Ia supernovae have been observed, which indirectly predict that they originate from white dwarfs with super-Chandrasekhar masses $2.1-2.8{\mathrm{M}}_{\odot }$. In this article, we discuss that considering white dwarfs as squashed fuzzy spheres, a class of noncommutative geometry, helps in accumulating more mass than the Chandrasekhar mass-limit. The length-scale beyond which the effect of noncommutativity becomes prominent is an emergent phenomenon, which depends only on the inter-electron separations in the white dwarf.

    ↳ gr-qcastro-ph.HEhep-phquant-ph0 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.