Mon·Dec 20, 2021Monday·December 20, 2021

1. 01*

   Flavor Seesaw Mechanism

   Sudip Jana🇩🇪 · Sophie Klett🇩🇪 · Manfred Lindner🇩🇪

   In the Standard Model, Yukawa couplings parametrize the fermion masses and mixing angles with the exception of neutrino masses. The hierarchies and apparent regularities among the quark and lepton masses are, however, otherwise a mystery. We propose a new class of models having vector-like fermions that can potentially address this problem and provide a new mechanism for fermion mass generation. The masses of the third and second generations of quarks and leptons arise at tree level via the seesaw mechanism from new physics at moderately higher scales, while loop corrections produce the masses for the first generation. This mechanism has a number of interesting and testable consequences. Among them are unavoidable flavor-violating signals at the upcoming experiments and the fact that neutrinos have naturally only Dirac masses.

   hep-phPRD(2022)·22 citations
2. 02*

   Production of charged Higgs $H^{\pm }$ through $cb$-fusion at LHC

   J. Hernández-Sánchez🇲🇽 · C. G. Honorato🇲🇽 · S. Moretti🇬🇧 · S. Rosado-Navarro🇲🇽

   Considering the framework of the 2-Higgs Doublet Model Type III (2HDM-III), wherein two doublets are coupled both to up as down fermions, and the Flavour Changin Currents (FCNCs) is controlled by a four-zero Texture approach in the Yukawa matrices. We study the production of charged Higgs ($H^{\pm }$) by means of $cb$ quark fusion followed by channel decay $H^{\pm }\to {\tau }^{\pm }\nu$ : $cb\to H^{\pm }\to {\tau }^{\pm }\bar{\nu }$. Taking in account the experimental bounds, as well as the theoretical constraints analysed in previous work arXiv:2003.06263[hep-ph]. One can show that in a lepton-specific-like incarnation of the model, we obtain a significant sensitivity for the LHC machine. We consider in the aforementioned study to both irreducible and reducible backgrounds of the SM.

   hep-ph0 citations
3. 03*

   Hunting Squarks in Higgsino LSP scenarios at the LHC

   Ernesto Arganda🇪🇸 · Antonio Delgado🇺🇸 · Roberto A. Morales🇦🇷 · Mariano Quirós🇪🇸

   The assumption that strongly interacting sparticles will decay directly to the LSP plus jets breaks down in situations where those decays are Yukawa suppressed. That occurs when producing the first two generations of squarks and when, at the same time, there are several electroweakinos lighter than those squarks. In this paper we analyze the signal of pair production of squarks that subsequently decay to an intermediate neutralino (${\tilde{\chi }}_3^0$) plus jets. The neutralino will then decay to the LSP (mainly higgsino) and a Higgs. We have simulated the events and designed a discovery strategy based on a signal of two jets, four $b$-quarks and missing transverse energy. We obtain very promising values for the LHC sensitivity at 14 TeV and 300 fb${}^{-1}$.

   hep-phPRD(2023)·1 citation
4. 04*

   Concerning pion parton distributions

   Z.-F. Cui🇨🇳 · M. Ding🇩🇪 · J. M. Morgado🇪🇸 · K. Raya🇪🇸 · D. Binosi🇮🇹 · L. Chang🇨🇳 · J. Papavassiliou🇪🇸 · C. D. Roberts🇨🇳 · J. Rodríguez-Quintero🇪🇸 · S. M. Schmidt🇩🇪

   Analyses of the pion valence-quark distribution function (DF), $u^{\pi }(x;\zeta )$, which explicitly incorporate the behaviour of the pion wave function prescribed by quantum chromodynamics (QCD), predict $u^{\pi }(x\simeq 1;\zeta )\sim (1-x{)}^{\beta (\zeta )}$, $\beta (\zeta \gtrsim m_p)>2$, where $m_p$ is the proton mass. Nevertheless, more than forty years after the first experiment to collect data suitable for extracting the $x\simeq 1$ behaviour of $u^{\pi }$, the empirical status remains uncertain because some methods used to fit existing data return a result for $u^{\pi }$ that violates this constraint. Such disagreement entails one of the following conclusions: the analysis concerned is incomplete; not all data being considered are a true expression of qualities intrinsic to the pion; or QCD, as it is currently understood, is not the theory of strong interactions. New, precise data are necessary before a final conclusion is possible. In developing these positions, we exploit a single proposition, viz. there is an effective charge which defines an evolution scheme for parton DFs that is all-orders exact. This proposition has numerous corollaries, which can be used to test the character of any DF, whether fitted or calculated.

   hep-phhep-exhep-latnucl-ex+1EPJA(2022)·57 citations
5. 05*

   Electroweak effects in polarized muon-electron scattering

   A.B. Arbuzov (1,2)🇷🇺 · S.G. Bondarenko (1)🇷🇺 · L.V. Kalinovskaya (3)🇷🇺 · L.A. Rumyantsev (3)🇷🇺 · V.L. Yermolchyk (3,4) ((1) Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna, 141980 Russia (2) Department of higher mathematics, Dubna State University, Dubna, 141982 Russia (3) Dzhelepov Laboratory of Nuclear Problems, Joint Institute for Nuclear Research, Dubna, 141980 Russia (4) Institute for Nuclear Problems, Belarusian State University, Minsk, 220006 Belarus)🇷🇺

   A theoretical description of elastic polarized muon-electron scattering is presented. Complete one-loop electroweak radiative corrections are calculated with taking into account the exact dependence on the muon mass. The effects due to some higher order corrections and the electroweak scheme dependence are analyzed. The case of longitudinally polarized fermions in the initial state is investigated. Analytical results are derived with the help of the SANC system. Numerical results are presented for unpolarized and polarized cross sections. Calculations are realized in the Monte Carlo integrator MCSANCee and generator ReneSANCe which allow the implementation of any experimental cut used in the analysis of elastic $\mu -e$ scattering data.

   hep-phPRD(2022)·8 citations
6. 06*

   Alternative signatures of the quintuplet fermions at the LHC and future linear colliders

   Nilanjana Kumar🇮🇳 · Vandana Sahdev🇮🇳

   Large fermionic multiplets appear in different extensions of the Standard Model (SM), which are essential to predict small neutrino masses, relic abundance of the dark matter (DM) and the measured value of muon anomalous magnetic moment (muon (g-2)). Models containing quintuplet of fermions ($\Sigma$), along with other scalar multiplets, can address recent anomalies in the flavor sector while satisfying the constraints from the electroweak physics. In standard scenarios, the exotic fermions couple with the SM particles directly and there exists a strong limit on their masses from collider experiments such as the Large Hadron Collider (LHC). In this paper, we choose a particular scenario where the quintuplet fermions are heavier than the scalars, which is naturally motivated from the muon (g-2) data. A unique nature of these models is that they predict non-standard signatures at the colliders as the quintuplet fermions decay via the scalars once produced at the colliders. We study these non-standard interactions and provide alternative search strategies for these exotic fermions at the LHC and future linear colliders (such as $e^{+}{e}^{-}$ colliders). We also discuss their exclusion and discovery limits. For the doubly charged quintuplet fermion (${\Sigma }^{\pm \pm }$), discovery is possible with 5$\sigma$ significance at integrated luminosity of 3000 fb${}^{-1}$ at 14 TeV LHC if $M_{\Sigma }\le 980$ GeV. For the singly charged quintuplet fermion (${\Sigma }^{\pm }$), the discovery is challenging at LHC but there might be a possibility of 5 $\sigma$ discovery with 1000 fb${}^{-1}$ luminosity at $e^{+}{e}^{-}$ collider for $M_{\Sigma }\le 700$ GeV.

   hep-phPRD(2022)·8 citations
7. 07*

   Chiral symmetry restoration with three chiral partners

   Juan M. Torres-Rincon🇩🇪

   I discuss the masses of chiral partners in the context of chiral symmetry restoration at finite temperature. Using the Nambu-Jona-Lasinio model I first remind the usual situation where two mesons of opposed parity become degenerate above the chiral transition temperature. Then I consider an effective theory for D mesons where the positive parity companion presents a "double pole structure". In this case three different masses need to be analyzed as functions of the temperature. I suggest a possible restoration pattern at high temperatures when the back-reaction of the quark condensate is incorporated.

   hep-phSciPost Phys.Proc.(2022)·1 citation
8. 08*

   Thermal freeze-out parameters and pseudo-entropy from charged hadron spectra in high energy collisions

   Xu-Hong Zhang🇨🇳 · Ya-Qin Gao🇨🇳 · Fu-Hu Liu🇨🇳 · Khusniddin K. Olimov🇺🇿

   We collected the transverse momentum (mass) spectra of charged hadrons (${\pi }^{-}$, ${\pi }^{+}$, $K^{-}$, $K^{+}$, $\overline{p}$, and $p$) produced in collisions over a center-of-mass energy range from 2.70 to 200 GeV (per nucleon pair). The modified Tsallis--Pareto-type function (the TP-like function) with average transverse flow velocity is used to describe the contribution of participant or constituent quarks to transverse momentum of considered hadron. The experimental spectra of ${\pi }^{\mp }$ and $K^{\mp }$ (or $\overline{p}$ and $p$) are fitted by the convolution of two (or three) TP-like functions due to the fact that two (or three) constituent quarks are regarded as two (or three) energy resources in the formation of considered hadron. From the reasonable fits to the spectra, the thermal freeze-out parameters are extracted, and the pseudo-entropy is newly defined and extracted. Some parameters quickly change in the energy range of less than 7.7 GeV, and slowly change in the energy range of greater than 7.7 GeV, indicating the variation of collision mechanism at around 7.7 GeV.

   hep-phhep-exnucl-exnucl-thAdv.High Energy Phys.(2022)·8 citations
9. 09*

   Probing New Physics at Future Tau Neutrino Telescopes

   Guo-yuan Huang🇩🇪 · Sudip Jana🇩🇪 · Manfred Lindner🇩🇪 · Werner Rodejohann🇩🇪

   We systematically investigate new physics scenarios that can modify the interactions between neutrinos and matter at upcoming tau neutrino telescopes, which will test neutrino-proton collisions with energies $\gtrsim 45\mathrm{TeV}$, and can provide unique insights to the elusive tau neutrino. At such high energy scales, the impact of parton distribution functions of second and third generations of quarks (usually suppressed) can be comparable to the contribution of first generation with small momentum fraction, hence making tau neutrino telescopes an excellent facility to probe new physics associated with second and third families. Among an inclusive set of particle physics models, we identify new physics scenarios at tree level that can give competitive contributions to the neutrino cross sections while staying within laboratory constraints: charged/neutral Higgs and leptoquarks. Our analysis is close to the actual experimental configurations of the telescopes, and we perform a ${\chi }^2$-analysis on the energy and angular distributions of the tau events. By numerically solving the propagation equations of neutrino and tau fluxes in matter, we obtain the sensitivities of representative upcoming tau neutrino telescopes, GRAND, POEMMA and Trinity, to the charged Higgs and leptoquark models. While each of the experiments can achieve a sensitivity better than the current collider reaches for certain models, their combination is remarkably complementary in probing the new physics. In particular, the new physics will affect the energy and angular distributions in different ways at those telescopes.

   hep-phastro-ph.HEhep-exJCAP(2022)·33 citations
10. 10*

    Effective Dirac neutrino mass operator in the Standard Model with a local Abelian extension

    Diego Restrepo🇨🇴 · David Suarez🇨🇴

    We present 48 types of solutions to the anomaly cancellation conditions of local Abelian extensions of the Standard Model (SM) with right-handed singlet chiral fermions. At least two of them acquire effective light Dirac neutrino masses, while the others get heavy masses from the spontaneous symmetry breaking of the local Abelian symmetry, forming a dark sector with multi-component and multi-generational fermionic dark matter. The corresponding effective Dirac neutrino mass operator can be realized at tree-level or radiatively by introducing extra scalars, and in some cases after imposing extra scotogenic conditions. The Dirac Zee model with Dirac fermionic dark matter is presented as an example of model where the neutrino and dark matter phenomenology are basically independent of each other.

    hep-phFront.in Phys.(2022)·5 citations
11. 11*

    Phenomenology of jet angularities at the LHC

    Daniel Reichelt🇬🇧 · Simone Caletti🇮🇹 · Oleh Fedkevych🇮🇹 · Simone Marzani🇮🇹 · Steffen Schumann🇩🇪 · Gregory Soyez🇫🇷

    We compute resummed and matched predictions for jet angularities in hadronic dijet and Z+jet events with and without grooming the candidate jets using the SoftDrop technique. Our theoretical predictions also account for non-perturbative corrections from the underlying event and hadronisation through parton-to-hadron level transfer matrices extracted from dedicated Monte Carlo simulations with SHERPA. Thanks to this approach we can account for non-perturbative migration effects in both the angularities and the jet transverse momentum. We compare our predictions against recent measurements from the CMS experiment. This allows us to test the description of quark- and gluon-jet enriched phase-space regions separately. We supplement our study with SHERPA results based on the matching of NLO QCD matrix elements with the parton shower. Both theoretical predictions offer a good description of the data, within the experimental and theoretical uncertainties. The latter are however sizeable, motivating higher-accuracy calculations.

    hep-phhep-exJHEP(2022)·59 citations
12. 12*

    Earth as a transducer for axion dark-matter detection

    Ariel Arza🇷🇺 · Michael A. Fedderke🇺🇸 · Peter W. Graham🇺🇸 · Derek F. Jackson Kimball🇺🇸 · Saarik Kalia🇺🇸

    We demonstrate that ultralight axion dark matter with a coupling to photons induces an oscillating global terrestrial magnetic field signal in the presence of the background geomagnetic field of the Earth. This signal is similar in structure to that of dark-photon dark matter that was recently pointed out and searched for in [arXiv:2106.00022] and [arXiv:2108.08852]. It has a global vectorial pattern fixed by the Earth's geomagnetic field, is temporally coherent on long time scales, and has a frequency set by the axion mass $m_a$. In this work, we both compute the detailed signal pattern, and undertake a search for this signal in magnetometer network data maintained by the SuperMAG Collaboration. Our analysis identifies no strong evidence for an axion dark-matter signal in the axion mass range $2\times 10^{-18}\text{eV}\lesssim m_a\lesssim 7\times 10^{-17}\text{eV}$. Assuming the axion is all of the dark matter, we place constraints on the axion-photon coupling $g_{a\gamma }$ in the same mass range; at their strongest, for masses $3\times 10^{-17}\text{eV}\lesssim m_a\lesssim 4\times 10^{-17}\text{eV}$, these constraints are comparable to those obtained by the CAST helioscope.

    hep-phastro-ph.COPRD(2022)·59 citations
13. 13*

    Chiral models of composite axions and accidental Peccei-Quinn symmetry

    Roberto Contino🇮🇹 · Alessandro Podo🇺🇸 · Filippo Revello🇬🇧

    We introduce a class of composite axion models that provide a natural solution to the strong CP problem, and possibly account for the observed dark matter abundance. The QCD axion arises as a composite Nambu-Goldstone boson (NGB) from the dynamics of a chiral gauge theory with a strongly-interacting and confining SU(N) factor and a weakly-interacting U(1), with no fundamental scalar fields. The Peccei-Quinn (PQ) symmetry is accidental and all the mass scales are generated dynamically. We analyze specific models where the PQ symmetry is broken only by operators of dimension 12 or higher. We also classify several other models where the PQ symmetry can be potentially protected up to the dimension 15 or 18 level. Our framework can be easily extended to a scenario where the Standard Model (SM) is unified into a simple gauge group, and we discuss the case of non-supersymmetric SU(5) unification. The GUT models predict the existence of additional pseudo NGBs, parametrically lighter than the GUT and PQ scales, which could have an impact on the cosmological evolution and leave observable signatures. We also clarify the selection rules under which higher-dimensional PQ-violating operators can generate a potential for the axion in the IR, and provide a discussion of the discrete symmetries in composite axion models associated to the number of domain walls. These results can be of general interest for composite axion models based on a QCD-like confining gauge group.

    hep-phhep-thJHEP(2022)·51 citations
14. 14*

    Tagging the Higgs boson decay to bottom quarks with colour-sensitive observables and the Lund jet plane

    Luca Cavallini🇮🇹 · Andrea Coccaro🇮🇹 · Charanjit K. Khosa🇮🇹 · Giulia Manco🇮🇹 · Simone Marzani🇮🇹 · Fabrizio Parodi🇮🇹 · Daniela Rebuzzi🇮🇹 · Alberto Rescia🇮🇹 · Giovanni Stagnitto🇨🇭

    We study the problem of distinguishing $b$-jets stemming from the decay of a colour singlet, such as the Higgs boson, from those originating from the abundant QCD background. In particular, as a case study, we focus on associate production of a vector boson and a Higgs boson decaying into a pair of $b$-jets, which has been recently observed at the LHC. We consider the combination of several theory-driven observables proposed in the literature, together with Lund jet plane images, in order to design an original $Hbb$ tagger. The observables are combined by means of standard machine learning algorithms, which are trained on events obtained with fast detector simulation techniques. We find that the combination of high-level single-variable observables with the Lund jet plane provides an excellent discrimination performance. We also study the dependence of the tagger on the invariant mass of the decaying particles, in order to assess the extension to a generic $Xbb$ tagger.

    hep-phhep-exEPJC(2022)·23 citations
15. 15*

    On-shell Higgsing for EFTs

    Reuven Balkin🇮🇱 · Gauthier Durieux🇨🇭 · Teppei Kitahara🇯🇵 · Yael Shadmi🇮🇱 · Yaniv Weiss🇮🇱

    We study the on-shell version of the Higgs mechanism in effective theories (EFTs) containing particles of different spins, focusing on contact terms as a simple starting point. We derive the massive contact terms and their coefficients from the massless amplitudes of the EFT above the symmetry breaking scale, by covariantizing the massless contact terms under the massive little group. In the little-group-covariant massive-spinor formalism, this notationally amounts to bolding spinor labels. Mass-suppressed contributions to the contact-term coefficients arise from higher-point contact terms with additional soft Higgs legs. We apply this procedure to obtain massive four-point amplitudes featuring scalars, spin 1/2 fermions and vectors, in the standard-model EFT. The subleading helicity-flipped components of each massive contact term, which are dictated by little-group covariance, are associated with the residues of factorizable massless amplitudes. Extra "frozen" Higgses emitted from each leg of a massless contact term supply the additional light-like momentum component, needed to form a massive leg of the same polarization. As another application, we derive various components of massive three-point amplitudes from massless amplitudes with up to three additional Higgses, in a standard-model-like toy model.

    hep-phhep-thJHEP(2022)·41 citations
16. 16*

    The Phonon Background from Gamma Rays in Sub-GeV Dark Matter Detectors

    Kim V. Berghaus🇺🇸 · Rouven Essig🇺🇸 · Yonit Hochberg🇮🇱 · Yutaro Shoji🇮🇱 · Mukul Sholapurkar🇺🇸

    High-energy photons with $\mathcal{O}$(MeV) energies from radioactive contaminants can scatter in a solid-state target material and constitute an important low-energy background for sub-GeV dark matter direct-detection searches. This background is most noticeable for energy deposits in the $1-100$ meV range due to the partially coherent scattering enhancement in the forward scattering direction. We comprehensively quantify the resulting single- and multi-phonon background in Si, Ge, GaAs, SiC, and Al${}_2$O${}_3$ target materials, which are representative of target materials of interest in low-mass dark matter searches. We use a realistic representation of the high-energy photon background, and contrast the expected background phonon spectrum with the expected dark matter signal phonon spectrum. An active veto is needed to suppress this background sufficiently in order to allow for the detection of a dark matter signal, even in well-shielded environments. For comparison we also show the expected single- and multi-phonon event rates from coherent neutrino-nucleus scattering due to solar neutrinos, and find that they are sub-dominant to the photon-induced phonon background.

    hep-phastro-ph.COhep-exPRD(2022)·19 citations
17. 17*

    ChiliPDF: Chebyshev Interpolation for Parton Distributions

    Markus Diehl🇩🇪 · Riccardo Nagar🇮🇹 · Frank J. Tackmann🇩🇪

    Parton distribution functions (PDFs) are an essential ingredient for theoretical predictions at colliders. Since their exact form is unknown, their handling and delivery for practical applications relies on approximate numerical methods. We discuss the implementation of PDFs based on a global interpolation in terms of Chebyshev polynomials. We demonstrate that this allows for significantly higher numerical accuracy at lower computational cost compared with local interpolation methods such as splines. Whilst the numerical inaccuracy of currently used local methods can become a nontrivial limitation in high-precision applications, in our approach it is negligible for practical purposes. This holds in particular for differentiation and for Mellin convolution with kernels that have end point singularities. We illustrate our approach for these and other important numerical operations, including DGLAP evolution, and find that they are performed accurately and fast. Our results are implemented in the C++ library ChiliPDF.

    hep-phEPJC(2022)·25 citations
18. 18*

    Interplay between Resonant Leptogenesis, Neutrinoless Double Beta Decay and Collider Signals in a Model with Flavor and CP Symmetries

    Garv Chauhan🇧🇪 · P. S. Bhupal Dev🇺🇸

    We present a low-scale type-I seesaw scenario with discrete flavor and CP symmetries. This scenario not only explains the measured values of the lepton mixing angles, but also makes predictions for leptonic CP violation, and connects the low-energy CP phases relevant for neutrino oscillation and neutrinoless double beta decay experiments with the high-energy CP phases relevant for leptogenesis. We show that the three right-handed Majorana neutrinos in this scenario have (almost) degenerate masses and their decays can explain the observed baryon asymmetry of the Universe via resonant leptogenesis. We study the correlation of the predicted baryon asymmetry with lepton-number-violating signals at high-energy colliders, including both prompt and displaced vertex/long-lived signatures, as well as in low-energy neutrinoless double beta decay experiments. We find that the normal ordering of light neutrino masses leads to an enhanced collider signal, whereas the neutrinoless double beta decay provides a promising probe in the inverted ordering case.

    hep-phNPB(2023)·25 citations
19. 19*

    Searching for light new physics at the LHC via lepton-number violation

    Wafia Bensalem🇨🇦 · David London🇨🇦 · Daniel Stolarski🇨🇦 · Alberto Tonero🇨🇦

    We study the collider phenomenology of a simplified model containing a right-handed $W$ in which the $W_R$ couples predominantly to the third generation in the quark sector. The model also includes a light Majorana neutrino, with $M_1\sim \mathcal{O}(100)$ GeV, giving rise to lepton-number-violating signatures that are visible at the LHC. Taking into account all the searches from the LHC and Tevatron, we find that this $W_R$ can still be as light as $M_R\sim 300$ GeV. We show that this type of new physics, and others like it, can be detected at the LHC using final states with three same-sign same-flavour leptons.

    hep-phhep-exJHEP(2022)·1 citation
20. 20*

    Solar mass black holes from neutron stars and bosonic dark matter

    Raghuveer Garani🇮🇹 · Dmitry Levkov🇷🇺 · Peter Tinyakov🇧🇪

    Black holes with masses $\approx 1M_{\odot }$ cannot be produced via stellar evolution. A popular scenario of their formation involves transmutation of neutron stars - by accumulation of dark matter triggering gravitational collapse in the star centers. We show that this scenario can be realized in the models of bosonic dark matter despite the apparently contradicting requirements on the interactions of dark matter particles: on the one hand, they should couple to neutrons strongly enough to be captured inside the neutron stars, on the other, their loop-induced self-interactions impede collapse. Observing that these conflicting conditions are imposed at different scales, we demonstrate that models with efficient accumulation of dark matter can be deformed at large fields to make unavoidable its subsequent collapse into a black hole. Workable examples include weakly coupled models with bended infinite valleys.

    hep-phastro-ph.COastro-ph.HEPRD(2022)·32 citations
21. 21*

    Incorporating the weak mixing angle dependence to reconcile the neutron skin measurement on 208Pb by PREX-II

    Mattia Atzori Corona🇮🇹 · Matteo Cadeddu🇮🇹 · Nicola Cargioli🇮🇹 · Paolo Finelli🇮🇹 · Matteo Vorabbi🇺🇸

    The only available electroweak measurement of the ${}^{208}\mathrm{Pb}$ neutron skin, $\Delta R_{\mathrm{np}}$, performed by the PREX-II Collaboration through polarized electron-lead scattering, shows a mild tension with respect to both the theoretical nuclear-model predictions and a host of measurements. However, the dependence on the weak mixing angle should be incorporated in the calculation, since its low-energy value is experimentally poorly known. We first repeat the PREX-II analysis confirming their measurement by fixing the weak mixing angle to its standard model value. Then, we show the explicit dependence of the PREX-II measurement on the weak mixing angle, obtaining that it is fully degenerate with the neutron skin. To break this degeneracy, we exploit the weak mixing angle measurement from atomic parity violation on lead, obtaining a slightly thinner neutron skin but with about doubled uncertainties, possibly easing the PREX tension. Relying on the theoretical prediction, $\Delta R_{\mathrm{np}}^{\mathrm{th}}\approx 0.13-0.19\mathrm{fm}$, and using it as a prior in the fit, we find a weak mixing angle value about $1.2\sigma$ smaller than the standard model prediction. Thus, we suggest a possible solution of the PREX-II tension by showing that, considering its underlying dependence on the weak mixing angle, the PREX-II neutron skin determination could be in agreement with the other available measurements and predictions if the weak mixing angle at the proper energy scale is smaller than the standard model prediction.

    hep-phnucl-exnucl-thPRC(2022)·20 citations
22. 22*

    Locating the special point of hybrid neutron stars

    Mateusz Cierniak🇵🇱 · David Blaschke🇵🇱

    The special point is a feature unique to models of hybrid neutron stars. It represents a location on their mass--radius sequences that is insensitive to the phase transition density. We consider hybrid neutron stars with a core of deconfined quark matter that obeys a constant--sound--speed (CSS) equation of state model and provide a fit formula for the coordinates of the special point as functions of the squared sound speed ($c_s^2$) and pressure scale ($A$) parameters. Using the special point mass as a proxy for the maximum mass of the hybrid stars we derive limits for the CSS model parameters based on the recent NICER constraint on mass and radius of pulsar PSR J0740+6620, $0.36<{c_s^2}_{\min }<0.43$ and $80<A[{MeV/fm}^3]<160$. The upper limit for the maximum mass of hybrid stars depends on the upper limit for $c_s^2$ so that choosing $c_{s,max}^2=0.6$ results in $M_{\max }<2.7M_{\odot }$, within the mass range of GW190814.

    ↳ nucl-thastro-ph.HEhep-phEPJ Web Conf.(2022)·8 citations
23. 23*

    Towards Probing the Diffuse Supernova Neutrino Background in All Flavors

    Anna M. Suliga🇺🇸 · John F. Beacom🇺🇸 · Irene Tamborra🇩🇰

    Fully understanding the average core-collapse supernova requires detecting the diffuse supernova neutrino background (DSNB) in all flavors. While the DSNB ${\bar{\nu }}_e$ flux is near detection, and the DSNB ${\nu }_e$ flux has a good upper limit and prospects for improvement, the DSNB ${\nu }_x$ (each of ${\nu }_{\mu },{\nu }_{\tau },{\bar{\nu }}_{\mu },{\bar{\nu }}_{\tau }$) flux has a poor limit and heretofore had no clear path for improved sensitivity. We show that a succession of xenon-based dark matter detectors -- XENON1T (completed), XENONnT/LUX-ZEPLIN (running), and DARWIN (proposed) -- can dramatically improve sensitivity to DSNB ${\nu }_x$ the neutrino-nucleus coherent scattering channel. XENON1T could match the present sensitivity of $\sim 10^3{\mathrm{cm}}^{-2}{\mathrm{s}}^{-1}$ per ${\nu }_x$ flavor, XENONnT/LUX-ZEPLIN would have linear improvement of sensitivity with exposure, and a long run of DARWIN could reach a flux sensitivity of $\sim 10{\mathrm{cm}}^{-2}{\mathrm{s}}^{-1}$. Together, these would also contribute to greatly improve bounds on non-standard scenarios. Ultimately, to reach the standard flux range of $\sim 1{\mathrm{cm}}^{-2}{\mathrm{s}}^{-1}$, even larger exposures will be needed, which we show may be possible with the series of proposed lead-based RES-NOVA detectors.

    ↳ astro-ph.HEhep-phPRD(2022)·50 citations
24. 24*

    Confining density functional approach for color superconducting quark matter and mesonic correlations

    Oleksii Ivanytskyi🇵🇱 · David Blaschke🇵🇱 · Konstantin Maslov🇷🇺

    We present a novel relativistic density-functional approach to modeling quark matter with a mechanism to mimic confinement. The quasiparticle treatment of quarks provides their suppression due to large quark selfenergy already at the mean-field level. We demonstrate that our approach is equivalent to a chiral quark model with medium-dependent couplings. The dynamical restoration of the chiral symmetry is ensured by construction of the density functional. Beyond the mean field, quark correlations in the pseudoscalar channel are described within the Gaussian approximation. This explicitly introduces pionic states into the model. Their contribution to the thermodynamics potential is analyzed within the Beth-Uhlenbeck framework. The modification of the meson mass spectrum in the vicinity of thee (de)confinement transition is interpreted as the Mott transition. Supplemented with the vector repulsion and diquark pairing the model is applied to construct a hybrid quark-hadron EoS of cold compact-star matter. We study the connection of such a hybrid EoS with the stellar mass-radius relation and tidal deformability. The model results are compared to various observational constraints including the NICER radius measurement of PSR J0740+6620 and the tidal deformability constraint from GW170817. The model is shown to be consistent with the constraints, still allowing for further improvement by adjusting the vector repulsion and diquark pairing couplings.

    ↳ nucl-thhep-phEPJ Web Conf.(2022)·6 citations
25. 25*

    Vacuum decay in the Lorentzian path integral

    Takumi Hayashi🇯🇵 · Kohei Kamada🇯🇵 · Naritaka Oshita🇯🇵 · Jun'ichi Yokoyama🇯🇵

    We apply the Lorentzian path integral to the decay of a false vacuum and estimate the false-vacuum decay rate. To make the Lorentzian path integral convergent, the deformation of an integral contour is performed by following the Picard-Lefschetz theory. We show that the nucleation rate of a critical bubble, for which the corresponding bounce action is extremized, has the same exponent as the Euclidean approach. We also extend our computation to the nucleation of a bubble larger or smaller than the critical one to which the Euclidean formalism is not applicable.

    ↳ hep-thastro-ph.COgr-qchep-phJCAP(2022)·23 citations
26. 26*

    Composition of the inclusive semi-leptonic decay of B meson

    Gabriela Bailas🇯🇵 · Shoji Hashimoto🇯🇵

    Utilizing the approach recently proposed for the inclusive semi-leptonic decay rate on the lattice, we compute the differential decay rate of a $B_s$ meson for various kinematical channels. The results are compared with the contributions from the ground states (D and D^*) as well as from the orbitally excited states (D^**'s). The computation so far is carried out with an unphysically light bottom quark and strange spectator quark.

    ↳ hep-lathep-phPoS(2022)·3 citations
27. 27*

    Alpha-alpha scattering in the Multiverse

    Serdar Elhatisari🇹🇷 · Timo A. Lähde🇩🇪 · Dean Lee🇺🇸 · Ulf-G. Meißner🇩🇪 · Thomas Vonk🇩🇪

    We investigate the phase shifts of low-energy alpha-alpha scattering under variations of the fundamental parameters of the Standard Model, namely the light quark mass, the electromagnetic fine-structure constant as well as the QCD theta-angle. As a first step, we recalculate alpha-alpha scattering in our Universe utilizing various improvements in the adiabatic projection method, which leads to an improved, parameter-free prediction of the S- and D-wave phase shifts for laboratory energies below 10 MeV. We find that positive shifts in the pion mass have a small effect on the S-wave phase shift, whereas lowering the pion mass adds some repulsion in the two-alpha system. The effect on the D-wave phase shift turns out to be more pronounced as signaled by the D-wave resonance parameters. Variations of the fine-structure constant have almost no effect on the low-energy alpha-alpha phase shifts. We further show that up-to-and-including next-to-leading order in the chiral expansion, variations of these phase shifts with respect to the QCD theta-angle can be expressed in terms of the theta-dependent pion mass.

    ↳ hep-thastro-ph.COhep-lathep-ph+1JHEP(2022)·17 citations
28. 28*

    Circularization vs. Eccentrification in Intermediate Mass Ratio Inspirals inside Dark Matter Spikes

    Niklas Becker🇩🇪 · Laura Sagunski🇩🇪 · Lukas Prinz🇩🇪 · Saeed Rastgoo🇨🇦

    Inspirals of an Intermediate Mass Black Hole (IMBH) and a solar mass type object will be observable by space based gravitational wave detectors such as The Laser Interferometer Space Antenna (LISA). A dark matter overdensity around an IMBH - a dark matter spike - can affect the orbital evolution of the system. We consider here such Intermediate Mass Ratio Inspirals on eccentric orbits, experiencing dynamical friction of the dark matter spike. We find that by including the phase space distribution of the dark matter, the dynamical friction tends to circularize the orbit, in contrast to previous inquiries. We derive a general condition for circularization or eccentrification for any given dissipative force. In addition to the dephasing, we suggest using the circularization rate as another probe of the dark matter spike. Observing these effects would be an indicator for the particle nature of dark matter.

    ↳ gr-qcastro-ph.COhep-phPRD(2022)·70 citations
29. 29*

    Modelling and computational improvements to the simulation of single vector-boson plus jet processes for the ATLAS experiment

    ATLAS Collaboration

    This paper presents updated Monte Carlo configurations used to model the production of single electroweak vector bosons (W, Z/${\gamma }^{\ast }$) in association with jets in proton-proton collisions for the ATLAS experiment at the Large Hadron Collider. Improvements pertaining to the electroweak input scheme, parton-shower splitting kernels and scale-setting scheme are shown for multi-jet merged configurations accurate to next-to-leading order in the strong and electroweak couplings. The computational resources required for these set-ups are assessed, and approximations are introduced resulting in a factor three reduction of the per-event CPU time without affecting the physics modelling performance. Continuous statistical enhancement techniques are introduced by ATLAS in order to populate low cross-section regions of phase space and are shown to match or exceed the generated effective luminosity. This, together with the lower per-event CPU time, results in a 50% reduction in the required computing resources compared to a legacy set-up previously used by the ATLAS Collaboration. The set-ups described in this paper will be used for future ATLAS analyses and lay the foundation for the next generation of Monte Carlo predictions for single vector-boson plus jets production.

    ↳ hep-exhep-phJHEP(2022)·90 citations
30. 30*

    A Bayesian analysis of the properties of hybrid stars with the NJL model

    Antoine Pfaff🇫🇷 · Hubert Hansen🇫🇷 · Francesca Gulminelli🇫🇷

    We implement a Bayesian analysis of the properties of non-rotating hybrid stars at equilibrium with quark matter cores, as described by the SU(3) Nambu--Jona-Lasinio (NJL) model. The hadronic phase is described by a unified metamodeling approach, with a prior parameter space covering the present uncertainties on nuclear matter properties with nucleonic degrees of freedom. The parameter space of the NJL model includes vector-isoscalar and vector-isovector couplings and, additionally, an effective bag constant for the quark pressure is introduced as a free parameter. The phase transition is assumed to be first order with charge neutral phases, following the Maxwell construction. Our Bayesian framework includes filters on the experimental and theoretical low-density nuclear physics knowledge (atomic masses, ab initio calculations of the EoS) and high density constraints from astrophysical observations (maximum mass of J0348+0432, binary tidal deformability of the GW170817 event). We find that microscopic vector interactions play an important role in quark matter in order to stiffen the equation of state sufficiently to reach high star masses, in agreement with previous studies. Even within a very large prior for both the hadronic phase and the quark phase and the important freedom brought by the effective bag constant, our posterior quark cores tend to be relatively small and only appear in very heavy stars ($M\gtrsim 2M_{\odot }$). Coincidentally, the inclusion of the nucleon-quark transition (deconfinement transition) only weakly affects the radii of compact stars, foreshadowing a very low observability of a possible phase transition using x-ray radii measurements.

    ↳ astro-ph.HEhep-phnucl-thPRC(2022)·26 citations
31. 31*

    Proposed Lunar Measurements of $r$-Process Radioisotopes to Distinguish Origin of Deep-sea 244Pu

    Xilu Wang🇨🇳 · Adam M. Clark🇺🇸 · John Ellis🇬🇧 · Adrienne F. Ertel🇺🇸 · Brian D. Fields🇺🇸 · Brian J. Fry🇺🇸 · Zhenghai Liu🇨🇳 · Jesse A. Miller🇺🇸 · Rebecca Surman🇺🇸

    244Pu has recently been discovered in deep-sea deposits spanning the past 10 Myr, a period that includes two 60Fe pulses from nearby supernovae. 244Pu is among the heaviest $r$-process products, and we consider whether it was created in the supernovae, which is disfavored by nucleosynthesis simulations, or in an earlier kilonova event that seeded 244Pu in the nearby interstellar medium that was subsequently swept up by the supernova debris. We discuss how these possibilities can be probed by measuring 244Pu and other $r$-process radioisotopes such as 129I and 182Hf, both in lunar regolith samples returned to Earth by missions such as Chang'e and Artemis, and in deep-sea deposits.

    ↳ astro-ph.HEhep-phnucl-exnucl-th+1Astrophysics(2023)·13 citations
32. 32*

    The Final Model Building for the Supersymmetric Pati-Salam Models from Intersecting D6-Branes

    Weikun He🇰🇷 · Tianjun Li🇨🇳 · Rui Sun🇰🇷 · Lina Wu🇨🇳

    All the possible three-family $\mathcal{N}=1$ supersymmetric Pati-Salam models constructed with intersecting D6-branes from Type IIA orientifolds on $T^6/({\mathbb{Z}}_2\times {\mathbb{Z}}_2)$ are recently presented in arXiv: 2112.09632. Taking models with largest wrapping number $5$ and approximate gauge coupling unification at GUT scale as examples, we show string scale gauge coupling unification can be realized through two-loop renormalization group equation running by introducing seven pairs of vector-like particles from $\mathcal{N}=2$ sector. The number of these introduced vector-like particles are fully determined by the brane intersection numbers while there are two D6-brane parallel to each other along one two-torus. We expect this will solve the gauge coupling unification problem in the generic intersecting brane worlds by introducing vector-like particles that naturally included in the $\mathcal{N}=2$ sector.

    ↳ hep-thhep-phEPJC(2022)·14 citations
33. 33*

    The Complete Search for the Supersymmetric Pati-Salam Models from Intersecting D6-Branes

    Weikun He🇰🇷 · Tianjun Li🇨🇳 · Rui Sun🇰🇷

    We construct a systematic method to build all the possible three-family $\mathcal{N}=1$ supersymmetric Pati-Salam models from Type IIA orientifolds on ${\mathbb{T}}^6/({\mathbb{Z}}_2\times {\mathbb{Z}}_2)$ with intersecting D6-branes, in which the $SU(4{)}_C\times SU(2{)}_L\times SU(2{)}_R$ gauge symmetry can be broken down to the $SU(3{)}_C\times SU(2{)}_L\times U(1{)}_Y$ Standard Model gauge symmetry by the D-brane splitting and supersymmetry preserving Higgs mechanism. This is essentially achieved by solving all the common solutions for the RR tadpole cancellation conditions, $\mathcal{N}=1$ supersymmetry conditions, and three generation conditions with deterministic algorithm. We find that there are $202752$ possible supersymmetric Pati-Salam models in total, and show that there are only $33$ independent models with different gauge coupling relations at string scale after modding out equivalent relations, such as T-dualities, etc. In particular, there is one and only one independent model which has gauge coupling unification. Furthermore, one can construct other types of intersecting D-brane models utilizing such deterministic algorithm, and therefore we suggest a brand new method for D-brane model building.

    ↳ hep-thhep-phJHEP(2022)·23 citations
34. 34*

    On the Method of Brackets

    B. Ananthanarayan🇮🇳 · Sumit Banik🇮🇳 · Samuel Friot🇫🇷 · Tanay Pathak🇮🇳

    The Method of Brackets (MoB) is a technique used to compute definite integrals, that has its origin in the negative dimensional integration method. It was originally proposed for the evaluation of Feynman integrals for which, when applicable, it gives the results in terms of combinations of (multiple) series. We focus here on some of the limitations of MoB and address them by studying the Mellin-Barnes (MB) representation technique. There has been significant process recently in the study of the latter due to the development of a new computational approach based on conic hulls (see Phys. Rev. Lett. 127, 151601 (2021)). The comparison between the two methods helps to understand the limitations of the MoB, in particular when termwise divergent series appear. As a consequence, the MB technique is found to be superior over MoB for two major reasons: 1. the selection of the sets of series that form a series representation for a given integral follows, in the MB approach, from specific intersections of conic hulls, which, in contrast to MoB, does not need any convergence analysis of the involved series, and 2. MB can be used to evaluate resonant (i.e. logarithmic) cases where MoB fails due to the appearance of termwise divergent series. Furthermore, we show that the recently added Rule 5 of MoB naturally emerges as a consequence of the residue theorem in the context of MB.

    ↳ hep-thhep-phmath-phmath.MPPRD(2023)·18 citations
35. 35*

    Luminosity functions consistent with a pulsar-dominated Galactic Center Excess

    Jack T. Dinsmore🇺🇸 · Tracy R. Slatyer🇺🇸

    A new population of millisecond pulsars is a long-standing proposed explanation for the excess of GeV-scale gamma rays emanating from the region surrounding the center of the Milky Way (the "Galactic Center excess"). We examine several simple parameterizations of possible luminosity functions for this population, as well as several benchmark luminosity functions proposed in the literature, and compare the predicted populations of resolved point sources to the Fermi 4FGL-DR2 point source catalog and a sub-population recently identified using wavelet-based methods. We provide general results that can be used to translate upper limits on the number of resolved point sources associated with the excess, and the fraction of the flux in the excess that can be attributed to resolved sources, into limits on the luminosity function parameter space. We discuss a number of important systematic uncertainties, including in the detection threshold model and the total flux attributed to the excess. We delineate regions of parameter space (containing existing benchmark models) where there is no apparent tension with current data, and the number of total pulsars needed to explain the excess is in the range of O(10,000-100,000). Forecasting the effects of lowered point source detection thresholds, we show that novel analysis methods that probe sub-threshold point source populations can hope to resolve more than 30% of the flux of the excess.

    ↳ astro-ph.HEastro-ph.COhep-phJCAP(2022)·29 citations
36. 36*

    The Return of the Templates: Revisiting the Galactic Center Excess with Multi-Messenger Observations

    Ilias Cholis🇺🇸 · Yi-Ming Zhong🇺🇸 · Samuel D. McDermott🇺🇸 · Joseph P. Surdutovich🇺🇸

    The Galactic center excess (GCE) remains one of the most intriguing discoveries from the Fermi Large Area Telescope (LAT) observations. We revisit the characteristics of the GCE by first producing a new set of high-resolution galactic diffuse gamma-ray emission templates, which are ultimately due to cosmic-ray interactions with the interstellar medium. Using multi-messenger observations we constrain the properties of the galactic diffuse emission. The broad properties of the GCE that we find in this work are qualitatively unchanged despite the introduction of this new set of templates, though its quantitative features appear mildly different than those obtained in previous analyses. In particular, we find a high-energy tail at higher significance than previously reported. This tail is very prominent in the northern hemisphere, and less so in the southern hemisphere. This strongly affects one prominent interpretation of the excess: known millisecond pulsars are incapable of producing this high-energy emission, even in the relatively softer southern hemisphere, and are therefore disfavored as the sole explanation of the GCE. The annihilation of dark matter particles of mass $40_{-7}^{+10}$ GeV (95$\%$ CL) to $b$ quarks with a cross-section of $\sigma v=1.4_{-0.3}^{+0.6}\times 10^{-26}$ cm${}^3$s${}^{-1}$ provides a good fit to the excess especially in the relatively cleaner southern sky. Dark matter of the same mass range annihilating to $b$ quarks or heavier dark matter particles annihilating to heavier Standard Model bosons can combine with millisecond pulsars to provide a good fit to the southern hemisphere emission. As part of this paper, we make publicly available all of our templates and the data covariance matrix we have generated to account for systematic uncertainties.[abridged]

    ↳ astro-ph.HEastro-ph.COastro-ph.GAhep-phPRD(2022)·107 citations
37. 37*

    Hadrons, Better, Faster, Stronger

    Erik Buhmann🇩🇪 · Sascha Diefenbacher🇩🇪 · Engin Eren🇩🇪 · Frank Gaede🇩🇪 · Daniel Hundhausen🇩🇪 · Gregor Kasieczka🇩🇪 · William Korcari🇩🇪 · Katja Krüger🇩🇪 · Peter McKeown🇩🇪 · Lennart Rustige🇩🇪

    Motivated by the computational limitations of simulating interactions of particles in highly-granular detectors, there exists a concerted effort to build fast and exact machine-learning-based shower simulators. This work reports progress on two important fronts. First, the previously investigated WGAN and BIB-AE generative models are improved and successful learning of hadronic showers initiated by charged pions in a segment of the hadronic calorimeter of the International Large Detector (ILD) is demonstrated for the first time. Second, we consider how state-of-the-art reconstruction software applied to generated shower energies affects the obtainable energy response and resolution. While many challenges remain, these results constitute an important milestone in using generative models in a realistic setting.

    ↳ physics.ins-dethep-exhep-phphysics.data-anMach.Learn.Sci.Tech.(2022)·74 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.