Mon·Jun 14, 2021Monday·June 14, 2021

1. 01*

   Using atomic clocks to detect local dark matter halos

   Chris Kouvaris🇬🇷 · Eleftherios Papantonopoulos🇬🇷 · Lauren Street🇺🇸 · L.C.R. Wijewardhana🇺🇸

   It is possible that bosonic dark matter forms halos around the Sun or the Earth. We discuss the possibility of probing such halos with atomic clocks. Focusing on either a Higgs portal or photon portal interaction between the dark matter and the Standard Model, we search the possible parameter space for which a clock on Earth and a clock in space would have a discernible frequency difference. Bosonic dark matter halos surrounding the Earth can potentially be probed with current optical atomic clocks.

   hep-phastro-ph.COhep-thPRD(2021)·6 citations
2. 02*

   Leptons and other forces of Nature

   Subhankar Roy🇮🇳 · Sagar Tirtha Goswami🇮🇳

   Assuming that neutrinos are not Majorana fermions and the right handed Dirac neutrino does not exist, we propose a model in which the second and the third generations of the leptons are composites, while the first generation is fundamental. The composite states are formed by the fundamental leptons and two new fundamental hidden scalar particles. In addition, there exist two hidden forces besides the SM interactions. The gauge symmetry $SU(2{)}_L\otimes U(1{)}_Y\otimes U(1{)}_h\otimes SU(2{)}_h$ of the electroweak and the hidden forces breaks down to $U(1{)}_Y\otimes U(1{)}_h$ after the spontaneous symmetry breaking (SSB). We explain the neutrino masses in terms of the binding dynamics of a hidden force. The phenomenon of neutrino oscillation can also be explained by our model in a dynamical framework of the hidden forces

   hep-phJ.Phys.G(2022)·0 citations
3. 03*

   $B_c\to D^{(\ast )}\tau {\bar{\nu }}_{\tau }$ processes in an effective field theory approach

   Anupama Bhol🇮🇳 · Suchismita Sahoo🇮🇳 · Soram Robertson Singh🇮🇳

   We present a compressive study on rare semileptonic $B_c\to D^{(\ast )}\tau {\bar{\nu }}_{\tau }$ decays involving $b\to u\tau {\bar{\nu }}_{\tau }$ quark level transitions in an effective field theory approach. We consider the presence of an additional (pseudo)vector and (pseudo)scalar type interactions which can be either complex or real and constrain the new couplings using the existing data on $R_{D^{(\ast )}}$, $R_{J/\psi }$, $R_{\pi }^l$, Br($B_{u,c}\to \tau {\bar{\nu }}_{\tau }$) and Br($B\to \pi \tau {\bar{\nu }}_{\tau }$) parameters. In order to segregate the sensitivity of new coefficients, we check the effects of these couplings on the branching ratios, lepton non-universality and various angular observables of $B_c\to D^{(\ast )}\tau {\bar{\nu }}_{\tau }$ processes.

   hep-ph2 citations
4. 04*

   WimPyDD: an object-oriented Python code for the calculation of WIMP direct detection signals

   Injun Jeong🇰🇷 · Sunghyun Kang🇰🇷 · Stefano Scopel (Sogang U.)🇰🇷 · Gaurav Tomar (Technical U. of Munich)🇩🇪

   We introduce WimPyDD, a modular, object-oriented and customizable Python code that calculates accurate predictions for the expected rates in Weakly Interacting Massive Particle (WIMP) direct-detection experiments within the framework of Galilean-invariant non-relativistic effective theory in virtually any scenario, including inelastic scattering, an arbitrary WIMP spin and a generic WIMP velocity distribution in the Galactic halo. WimPyDD exploits the factorization of the three main components that enter in the calculation of direct detection signals: i) the Wilson coefficients that encode the dependence of the signals on the ultraviolet completion of the effective theory; ii) a response function that depends on the nuclear physics and on the main features of the experimental detector (acceptance, energy resolution, response to nuclear recoils); iii) a halo function that depends on the WIMP velocity distribution and that encodes the astrophysical inputs. In WimPyDD these three components are calculated and stored separately for later interpolation and combined together only as the last step of the signal evaluation procedure. This makes the phenomenological study of the direct detection scattering rate with WimPyDD transparent and fast also when the parameter space of the WIMP model has a large dimensionality.

   hep-phastro-ph.COComput.Phys.Commun.(2022)·32 citations
5. 05*

   Non-linear evolution in the re-summed next-to-leading order of perturbative QCD:\confronting the experimental data

   Carlos Contreras (UFTSM)🇨🇱 · Eugene Levin (Tel Aviv U./UTFSM)🇮🇱 · Michael Sanhueza (UTFSM)🇨🇱

   In this paper we compare the experimental HERA data with the next-to-leading order approach (NLO) of Ref.[C.~Contreras, E.~Levin, R.~Meneses and M.~Sanhueza,Eur. Phys. J. C 80 (2020) no.11, 1029). This approach includes the re-summed NLO corrections to the kernel of the evolution equation, the correct asymptotic behaviour in the NLO at $\tau =r^2{Q}_s^2\gg 1$; the impact parameter dependence of the saturation scale in accord with the Froissarrt theorem as well as the non-linear corrections. In this paper, we successfully describe the experimental data with the quality, which is not worse, than in the leading order fits with larger number of the phenomenological parameters. It is demonstrated, that the data could be described, taking into account both the diffusion on $\ln (k_T)$, which stems from perturbative QCD, and the Gribov's diffusion in impact parameters. It is shown an ability to describe the data at rather large values of ${\alpha }_S$.

   hep-phPRD(2021)·8 citations
6. 06*

   Quark-hadron duality for heavy meson mixings in the 't Hooft model

   Hiroyuki Umeeda🇹🇼

   We study local quark-hadron duality and its violation for the $D^0-{\bar{D}}^0$, $B_d^0-{\bar{B}}_d^0$ and $B_s^0-{\bar{B}}_s^0$ mixings in the 't Hooft model, offering a laboratory to test QCD in two-dimensional spacetime together with the large-$N_c$ limit. With the 't Hooft equation being numerically solved, the width difference is calculated as an exclusive sum over two-body decays. The obtained rate is compared to inclusive one that arises from four-quark operators to check the validity of the heavy quark expansion (HQE). In view of the observation in four-dimensions that the HQE prediction for the width difference in the $D^0-{\bar{D}}^0$ mixing is four orders of magnitude smaller than the experimental data, in this work we investigate duality violation in the presence of the GIM mechanism. We show that the order of magnitude of the observable in the $D^0-{\bar{D}}^0$ mixing is enhanced in the exclusive analysis relative to the inclusive counterpart, when the 4D-like phase space function is used for the inclusive analysis. By contrast, it is shown that for the $B_d^0-{\bar{B}}_d^0$ and $B_s^0-{\bar{B}}_s^0$ mixings, small yet non-negligible corrections to the inclusive result emerge, which are still consistent with what is currently indicated in four-dimensions.

   hep-phJHEP(2021)·11 citations
7. 07*

   Quantum logic inspired techniques for spacetime-symmetry tests with (anti-)protons

   Juan M. Cornejo🇩🇪 · Ralf Lehnert🇺🇸 · Malte Niemann🇩🇪 · Johannes Mielke🇩🇪 · Teresa Meiners🇩🇪 · Amado Bautista-Salvador🇩🇪 · Marius Schulte🇩🇪 · Diana Nitzschke🇩🇪 · Matthias J. Borchert🇯🇵 · Klemens Hammerer🇩🇪 · Stefan Ulmer🇯🇵 · Christian Ospelkaus🇩🇪

   Cosmological observations as well as theoretical approaches to physics beyond the Standard Model provide strong motivations for experimental tests of fundamental symmetries, such as CPT invariance. In this context, the availability of cold baryonic antimatter at CERN has opened an avenue for ultrahigh-precision comparisons of protons and antiprotons in Penning traps. This work discusses an experimental method inspired by quantum logic techniques that will improve particle localization and readout speed in such experiments. The method allows for sympathetic cooling of the (anti-)proton to its quantum-mechanical ground state as well as the readout of its spin alignment, replacing the commonly used continuous Stern-Gerlach effect. Both of these features are achieved through coupling to a laser-cooled `logic' ion co-trapped in a double-well potential. This technique will boost the measurement sampling rate and will thus provide results with lower statistical uncertainty, contributing to stringent searches for time dependent variations in the data. Such measurements ultimately yield extremely high sensitivities to CPT violating coefficients acting on baryons in the Standard-Model Extension, will allow the exploration of previously unmeasured types of symmetry violations, and will enable antimatter-based axion-like dark matter searches with improved mass resolution.

   hep-phphysics.atom-phquant-phNew J.Phys.(2021)·25 citations
8. 08*

   Anomalous couplings in associated $VH$ production with Higgs decay to massive $b$ quarks at NNLO in QCD

   Wojciech Bizoń🇩🇪 · Fabrizio Caola🇬🇧 · Kirill Melnikov🇩🇪 · Raoul Röntsch🇨🇭

   We combine the NNLO QCD description of Higgs boson production in association with an electroweak vector boson $V=W\mathrm{or}Z$ with a similarly-precise description of Higgs boson decays into a pair of massive $b$ quarks and with the anomalous couplings that modify interactions of the Higgs and electroweak vector bosons. The resulting numerical code provides the most advanced theoretical tool to investigate such anomalous couplings in the associated Higgs boson production process. We study the impact of anomalous couplings on fiducial cross sections and differential distributions and argue that, with increased QCD precision, smaller anomalous couplings become accessible in kinematic regions where the effects of higher-dimensional operators in the Standard Model Effective Field Theory remain small and the EFT expansion is under control.

   hep-phPRD(2022)·29 citations
9. 09*

   The Magnetic Field Effect on Thermodynamics of Hot QCD Matter using Extensive and non-Extensive Statistics

   Essam Tarek🇪🇬 · M.M.Ahmed🇪🇬 · Asmaa G. Shalaby🇪🇬

   We study in detail the thermodynamics of the quantum chromodynamics (QCD) matter utilizing two different statistics, extensive and non-extensive. The thermodynamics such as (pressure, number density, energy density , entropy and magnetization) are determined from both statistics at zero and non-zero magnetic field, eB = 0; 0:2; 0:3GeV^2. The magnetic field effect appears by adding a vacuum contribution to the free energy along side the thermal contribution. The extensive thermodynamics can be emerged from the resonance hadron gas model which is incorporated in the present work. Accordingly, we repeat our calculations at zero and non-zero magnetic field for the non-extensive statistics. The theoretical results of thermodynamical quantities calculated from both statistics are confronted to the lattice results which show a reasonable agreement with the extensive thermodynamics, but overrated in non-extensive thermodynamics at high temperature only and higher entropic index. The response of the QCD matter due to the magnetic field is additionally examined, and it is concluded that QCD matter is considered as a paramagnetic matter.

   hep-phhep-th0 citations
10. 10*

    Dispersion-theoretical analysis of the electromagnetic form factors of the nucleon: Past, present and future

    Yong-Hui Lin🇩🇪 · Hans-Werner Hammer🇩🇪 · Ulf-G. Meißner🇩🇪

    We review the dispersion-theoretical analysis of the electromagnetic form factors of the nucleon. We emphasize in particular the role of unitarity and analyticity in the construction of the isoscalar and isovector spectral functions. We present new results on the extraction of the nucleon radii, the electric and magnetic form factors and the extraction of $\omega$-meson couplings. All this is supplemented by a detailed calculation of the theoretical uncertainties, using bootstrap and Bayesian methods to pin down the statistical errors, while systematic errors are determined from variations of the spectral functions. We also discuss the physics of the time-like form factors and point out further issues to be addressed in this framework.

    hep-phhep-exhep-latnucl-ex+1EPJA(2021)·74 citations
11. 11*

    Vacuum birefringence at the Gamma Factory

    Felix Karbstein🇩🇪

    We explore the perspectives of studying vacuum birefringence at the Gamma Factory. To this end, we assess in detail the parameter regime which can be reliably analyzed resorting to the leading contribution to the Heisenberg-Euler effective Lagrangian. We explicitly show that -- contrarily to naive expectations -- this approach allows for the accurate theoretical study of quantum vacuum signatures up to fairly large photon energies. The big advantage of this parameter regime is the possibility of studying the phenomenon in experimentally realistic, manifestly inhomogeneous pump and probe field configurations. Thereafter, we focus on two specific scenarios giving rise to a vacuum birefringence effect for traversing gamma probe photons. In the first scenario the birefringence phenomenon is induced by a quasi-constant static magnetic field. In the second case it is driven by a counter-propagating high-intensity laser field.

    hep-phAnnalen Phys.(2022)·21 citations
12. 12*

    inclusiveAI: A machine learning representation of the $F_2$ structure function over all charted $Q^2$ and $x$ range

    S. Brown🇺🇸 · G. Niculescu🇺🇸 · I. Niculescu🇺🇸

    Structure function data provide insight into the nucleon quark distribution. They are relatively straightforward to extract from the world's vast, and growing, amount of inclusive lepto-production data. In turn, structure functions can be used to model the physical processes needed for planning and optimizing future experiments. In this paper a machine learning algorithm capable of predicting, using a unique set of parameters, the $F_2$ structure function, for four-momentum transfer $0.055\le Q^2\le 800.0$ GeV${}^2$ and for Bjorken $x$ from $2.8\times 10^{-5}$ to the pion threshold is presented. The model was trained and reproduces the hydrogen and the deuterium data at the 7~\% level, comparable with the average uncertainty of the experimental data. Extending the model to other nuclei or expanding the kinematic range are straightforward. The model is at least ten times faster than existing structure functions parameterizations, making it an ideal candidate for event generators and systematic studies.

    hep-phnucl-exPRC(2021)·2 citations
13. 13*

    Two-sided constraints on Lorentz Invariance violation from Tibet-AS$\gamma$ and LHAASO Very-High-Energy photon observations

    Petr Satunin🇷🇺

    We present new two-sided constraints on Lorentz Invariance violation energy scale for photons with quartic dispersion relation from recent gamma ray observations by Tibet-AS$\gamma$ and LHAASO experiments. The constraints are based on the consideration of the processes of photon triple splitting (superluminal scenario) and the suppression of shower formation (subluminal). The constraints in subluminal scenario are better than the pair production constraints and are the strongest in the literature.

    hep-phastro-ph.HEEPJC(2021)·12 citations
14. 14*

    A three Higgs doublet model with symmetry-suppressed flavour changing neutral currents

    Dipankar Das🇮🇳 · P.M. Ferreira🇵🇹 · António P. Morais🇵🇹 · Ian Padilla-Gay🇩🇰 · Roman Pasechnik🇸🇪 · J. Pedro Rodrigues🇵🇹

    We construct a three-Higgs doublet model with a flavour non-universal $\mathrm{U}(1)\times {\mathbb{Z}}_2$ symmetry. That symmetry induces suppressed flavour-changing interactions mediated by neutral scalars. New scalars with masses below the TeV scale can still successfully negotiate the constraints arising from flavour data. Such a model can thus encourage direct searches for extra Higgs bosons in the future collider experiments, and includes a non-trivial flavour structure.

    hep-phhep-exJHEP(2021)·15 citations
15. 15*

    Non-relativistic and potential non-relativistic effective field theories for scalar mediators

    Simone Biondini🇨🇭 · Vladyslav Shtabovenko🇩🇪

    Yukawa-type interactions between heavy Dirac fermions and a scalar field are a common ingredient in various extensions of the Standard Model. Despite of that, the non-relativistic limit of the scalar Yukawa theory has not yet been studied in full generality in a rigorous and model-independent way. In this paper we intend to fill this gap by initiating a series of investigations that make use of modern effective field theory (EFT) techniques. In particular, we aim at constructing suitable non-relativistic and potential non-relativistic EFTs of Yukawa interactions (denoted as NRY and pNRY respectively) in close analogy to the well known and phenomenologically successful non-relativistic QCD (NRQCD) and potential non-relativistic QCD (pNRQCD). The phenomenological motivation for our study lies in the possibility to explain the existing cosmological observations by introducing heavy fermionic dark matter particles that interact with each other by exchanging a light scalar mediator. A systematic study of this compelling scenario in the framework of non-relativistic EFTs (NREFTs) constitutes the main novelty of our approach as compared to the existing studies.

    hep-phJHEP(2021)·21 citations
16. 16*

    Hidden sectors and a multi-temperature universe

    Amin Aboubrahim🇩🇪 · Wan-Zhe Feng🇨🇳 · Pran Nath🇺🇸 · Zhu-Yao Wang🇺🇸

    A variety of supergravity and string based models contain hidden sectors which can play a role in particle physics phenomena and in cosmology. In this note we discuss the possibility that the visible sector and the hidden sectors in general live in different heat baths. Further, it is entirely possible that dark matter resides partially or wholly in hidden sectors in the form of dark Dirac fermions, dark neutralinos or dark photons. A proper analysis of dark matter and of dark forces in this case requires that one deals with a multi-temperature universe. We discuss the basic formalism which includes the multi-temperature nature of visible and hidden sectors in the analysis of phenomena observable in the visible sectors. Specifically we discuss the application of the formalism for explaining the velocity dependence of dark matter cross sections as one extrapolates from galaxy scales to scales of galaxy clusters. Here the dark photon exchange among dark fermions can produce the desired velocity dependent cross sections consistent with existing galactic cross section data indicating the existence of a new fifth (dark) force. We also discuss the possibility that the dark photon may constitute a significant portion of dark matter. We demonstrate a realization of this possibility in a universe with two hidden sectors and with the visible sector and the hidden sectors in different heat baths which allows a satisfaction of the constraints that the dark photon have a lifetime larger than the age of the universe and that its relic density be consistent with Planck data. Future directions for further work are discussed.

    hep-ph8 citations
17. 17*

    Many-gluon tree amplitudes on modern GPUs: A case study for novel event generators

    Enrico Bothmann🇩🇪 · Walter Giele🇺🇸 · Stefan Hoeche🇺🇸 · Joshua Isaacson🇺🇸 · Max Knobbe🇩🇪

    The compute efficiency of Monte-Carlo event generators for the Large Hadron Collider is expected to become a major bottleneck for simulations in the high-luminosity phase. Aiming at the development of a full-fledged generator for modern GPUs, we study the performance of various recursive strategies to compute multi-gluon tree-level amplitudes. We investigate the scaling of the algorithms on both CPU and GPU hardware. Finally, we provide practical recommendations as well as baseline implementations for the development of future simulation programs. The GPU implementations can be found at: https://www.gitlab.com/ebothmann/blockgen-archive.

    hep-phhep-exphysics.comp-phSciPost Phys.Codeb.(2022)·41 citations
18. 18*

    Higgs-boson production in top-quark fragmentation

    Colomba Brancaccio🇩🇪 · Michał Czakon🇩🇪 · Terry Generet🇩🇪 · Michael Krämer🇩🇪

    We compute the fragmentation functions for the production of a Higgs boson at $\mathcal{O}(y_t^2{\alpha }_s)$. As part of this calculation, the relevant splitting functions are also derived at the same perturbative order. Our results can be used to compute differential cross sections with arbitrary top-quark and Higgs-boson masses from massless calculations. They can also be used to resum logarithms of the form $\ln (p_T/m)$ at large transverse momentum $p_T$ to next-to-leading-logarithmic accuracy by solving the DGLAP equations.

    hep-phJHEP(2021)·11 citations
19. 19*

    A hidden, heavier resonance of the Higgs field

    M. Consoli🇮🇹

    In Veltman's original view, the Standard Model with a large Higgs particle mass of about 1 TeV was the natural completion of non-renormalizable Glashow model. This mass was thus a second threshold for weak interactions, as the W mass was for the non-renormalizable 4-fermion V-A theory. Today, after the observation of the narrow scalar resonance at 125 GeV, Veltman's large-mass idea seems to be ruled out. Yet, this is not necessarily true. Depending on the description of SSB in ${\Phi }^4$ theory, and by combining analytic calculations and lattice simulations, besides the known particle at 125 GeV, a new resonance of the Higgs field may also show up around 700 GeV. The peculiarity, though, is that this heavier state would couple to longitudinal vector bosons with the same typical strength of the low-mass state and thus represent a relatively narrow resonance. In this way, such hypothetical new resonance would naturally fit with some excess of 4-lepton events observed by ATLAS around 680 GeV. Analogous data from CMS are needed to confirm or disprove this interpretation. Implications of a two-mass structure for radiative corrections are also discussed.

    hep-phActa Phys.Polon.B(2021)·12 citations
20. 20*

    On the wall velocity dependence of electroweak baryogenesis

    Glauber C. Dorsch🇧🇷 · Stephan J. Huber🇬🇧 · Thomas Konstandin🇩🇪

    We re-evaluate the status of supersonic electroweak baryogenesis using a generalized fluid Ansatz for the non-equilibrium distribution functions. Instead of truncating the expansion to first order in momentum, we allow for higher order terms as well, including up to 21 fluctuations. The collision terms are computed analytically at leading-log accuracy. We also point out inconsistencies in the standard treatments of transport in electroweak baryogenesis, arguing that one cannot do without specifying an Ansatz for the distribution function. We present the first analysis of baryogenesis using the fluid approximation to higher orders. Our results support the recent findings that baryogenesis may indeed be possible even in the presence of supersonic wall velocities.

    hep-phastro-ph.COJCAP(2021)·68 citations
21. 21*

    The MicroBooNE Experiment, the NuMI Absorber, and Heavy Neutral Leptons

    Kevin J. Kelly🇺🇸 · Pedro A.N. Machado🇺🇸

    Motivated by the recent search for a Higgs-Portal Scalar decaying inside the MicroBooNE detector, we demonstrate that the same search can be used to constrain Heavy Neutral Leptons. These are gauge-singlet fermions that interact with the Standard Model by mixing with neutrinos only and could be related to the origin of neutrino masses. By recasting the results of the MicroBooNE Collaboration's analysis, we show that, for a Heavy Neutral Lepton that mixes predominantly with muon-flavored neutrinos, previously unexplored parameter space can be excluded for masses between 30 and 150 MeV. Additionally, we make our Monte Carlo tools publicly available.

    hep-phhep-exPRD(2021)·46 citations
22. 22*

    Superadiabatic basis in cosmological particle production: application to preheating

    Yusuke Yamada🇯🇵

    We discuss the adiabatic basis dependence of particle number in time-dependent backgrounds. In particular, we focus on preheating after inflation, and show that, for the optimal basis, the time dependence of the produced particle number can be well approximated by a simple connection formula, which can be obtained by analysing Stokes phenomenon in given backgrounds. As we show explicitly, the simple connection formula can describe various parameter regions such as narrow and broad resonance regime in a unified manner.

    ↳ hep-thastro-ph.COgr-qchep-phJCAP(2021)·23 citations
23. 23*

    On Discrete Anomalies in Chiral Gauge Theories

    Philip Boyle Smith🇬🇧 · Avner Karasik🇬🇧 · Nakarin Lohitsiri🇬🇧 · David Tong🇬🇧

    We study two well-known $SU(N)$ chiral gauge theories with fermions in the symmetric, anti-symmetric and fundamental representations. We give a detailed description of the global symmetry, including various discrete quotients. Recent work argues that these theories exhibit a subtle mod 2 anomaly, ruling out certain phases in which the theories confine without breaking their global symmetry, leaving a gapless composite fermion in the infra-red. We point out that no such anomaly exists. We further exhibit an explicit path to the gapless fermion phase, showing that there is no kinematic obstruction to realising these phases.

    ↳ hep-thhep-lathep-phJHEP(2022)·27 citations
24. 24*

    NNNLLA BFKL pomeron eigenvalue in the planar N=4 SYM theory

    V.N. Velizhanin🇷🇺

    We find the eigenvalue of the kernel of BFKL equation in the next-to-next-to-next-to-leading logarithm approximation (NNNLLA) in the planar N=4 SYM theory by using the quantum spectral curve to compute values at fixed spin, and reconstructing the general result using the LLL-algorithm, which also was used for the reconstruction of the general result for the intercept function for arbitrary conformal spin at fourth order, computed earlier in paper 1802.06908 up to the rational part. We have found, that a new type of harmonic sums enter into results. Those sums have the argument multiplied by factor two with compare to usual harmonic sums and contain the last imagine index, what reflect their relations with the multiple polylogarithms, generated by ``fourth root of unity''. The final result contains Catalan number, which did not appear early in the calculations for the anomalous dimension of twist-2 operators.

    ↳ hep-thhep-ph9 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.