Fri·Mar 16, 2018Friday·March 16, 2018

1. 01*

   Hunting All the Hidden Photons

   Martin Bauer🇩🇪 · Patrick Foldenauer🇩🇪 · Joerg Jaeckel🇩🇪

   We explore constraints on gauge bosons of a weakly coupled $U(1{)}_{B-L}$, $U(1{)}_{L_{\mu }-L_e}$, $U(1{)}_{L_e-L_{\tau }}$ and $U(1{)}_{L_{\mu }-L_{\tau }}$. To do so we apply the full constraining power of experimental bounds derived for a hidden photon of a secluded $U(1{)}_X$ and translate them to the considered gauge groups. In contrast to the secluded hidden photon that acquires universal couplings to charged Standard Model particles through kinetic mixing with the photon, for these gauge groups the couplings to the different Standard Model particles can vary widely. We take finite, computable loop-induced kinetic mixing effects into account, which provide additional sensitivity in a range of experiments. In addition, we collect and extend limits from neutrino experiments as well as astrophysical and cosmological observations and include new constraints from white dwarf cooling. We discuss the reach of future experiments in searching for these gauge bosons.

   hep-phJHEP(2018)·464 citations
2. 02*

   Higher-order condensate corrections to ${\rm Y}$ masses, leptonic decay rates and sum rules

   T. Rauh🇬🇧

   With the recent completion of NNNLO results, the perturbative description of the ${\rm Y}$ system has reached a very high level of sophistication. We consider the non-perturbative corrections as an expansion in terms of local condensates, following the approach pioneered by Voloshin and Leutwyler. The leading order corrections up to dimension eight and the potential NLO corrections at dimension four are computed and given in analytical form. We then study the convergence of the expansion for the masses, the leptonic decay rates and the non-relativistic moments of the ${\rm Y}$ system. We demonstrate that the condensate corrections to the ${\rm Y}(1S)$ mass exhibit a region with good convergence, which allows us to extract ${\overline{m}}_b({\overline{m}}_b)=4214\pm 37(\text{pert.}){}_{-22}^{+20}(\text{non-pert.})\text{ MeV}$, and show that non-perturbative contributions to the moments with $n\approx 10$ are negligible.

   hep-phJHEP(2018)·10 citations
3. 03*

   A model with flavor-dependent gauged $U(1{)}_{B-L_1}\times U(1{)}_{B-L_2-L_3}$ symmetry

   Linping Mu🇨🇳 · Hiroshi Okada🇹🇼 · Chao-Qiang Geng🇨🇳

   We propose a new model with flavor-dependent gauged $U(1{)}_{B-L_1}\times U(1{)}_{B-L_2-L_3}$ symmetry in addition to the flavor-blind one in the standard model. The model contains three right-handed neutrinos to cancel gauge anomalies and several Higgses to construct the measured fermion masses. We show the generic feature of the model and explore its phenomenology. In particular, we discuss the current bounds on the extra gauge bosons from the K and B meson mixings as well as the LEP and LHC data and focus on their contributions to the lepton flavor violating processes of ${\ell }_{i+1}\to {\ell }_i\gamma$ (i=1,2).

   hep-phCPC(2018)·5 citations
4. 04*

   Dark matter direct detection of a fermionic singlet at one loop

   Juan Herrero-Garcia🇦🇺 · Emiliano Molinaro🇩🇰 · Michael A. Schmidt🇦🇺

   The strong direct detection limits could be pointing to dark matter -- nucleus scattering at loop level. We study in detail the prototype example of an electroweak singlet (Dirac or Majorana) dark matter fermion coupled to an extended dark sector, which is composed of a new fermion and a new scalar. Given the strong limits on colored particles from direct and indirect searches we assume that the fields of the new dark sector are color singlets. We outline the possible simplified models, including the well-motivated cases in which the extra scalar or fermion is a Standard Model particle, as well as the possible connection to neutrino masses. We compute the contributions to direct detection from the photon, the $Z$ and the Higgs penguins for arbitrary quantum numbers of the dark sector. Furthermore, we derive compact expressions in certain limits, i.e., when all new particles are heavier than the dark matter mass and when the fermion running in the loop is light, like a Standard Model lepton. We study in detail the predicted direct detection rate and how current and future direct detection limits constrain the model parameters. In case dark matter couples directly to Standard Model leptons we find an interesting interplay between lepton flavor violation, direct detection and the observed relic abundance.

   hep-phEPJC(2018)·44 citations
5. 05*

   Role of neutrino mixing in accelerated proton decay

   Massimo Blasone🇮🇹 · Gaetano Lambiase🇮🇹 · Giuseppe Gaetano Luciano🇮🇹 · Luciano Petruzziello🇮🇹

   The inverse beta decay of accelerated protons has been analyzed both in the laboratory frame (where the proton is accelerated) and in the comoving frame (where the proton is at rest and interacts with the Fulling-Davies-Unruh thermal bath of electrons and neutrinos). The equality between the two rates has been exhibited as an evidence of the necessity of Fulling-Davies-Unruh effect for the consistency of Quantum Field Theory formalism. Recently, it has been argued that neutrino mixing can spoil such a result, potentially opening new scenarios in neutrino physics. In the present paper, we analyze in detail this problem and we find that, assuming flavor neutrinos to be fundamental and working within a certain approximation, the agreement can be restored.

   hep-phhep-thPRD(2018)·50 citations
6. 06*

   Probing the energy spectrum of hadrons in proton air interactions at ultrahigh energies through the fluctuations of the muon content of extensive air showers

   Lorenzo Cazon🇵🇹 · Ruben Conceição🇵🇹 · Felix Riehn🇵🇹

   We demonstrate that the shower-to-shower fluctuations of the muon content of extensive air showers correlate with the fluctuations of a variable of the first interaction of Ultra High Energy Cosmic Rays, which is computed from the fraction of energy carried by the hadrons that sustain the hadronic cascade. The influence of subsequent stages of the shower development is found to play a sub-dominant role. As a consequence, the shower-to-shower distribution of the muon content is a direct probe of the hadron energy spectrum of interactions beyond 100 TeV center of mass energies.

   hep-phastro-ph.HEPLB(2018)·52 citations
7. 07*

   Perturbations to $\mu -\tau$ symmetry, lepton Number Violation and baryogenesis in left-right symmetric Model

   Happy Borgohain🇮🇳 · Mrinal Kumar Das🇮🇳

   In this work, we studied baryogenesis via leptogenesis, neutrinoless double beta decay (NDBD) in the framework of LRSM where type I and type II seesaw terms arises naturally. The type I seesaw mass term is considered to be favouring $\mu -\tau$ symmetry, taking into account the widely studied realizations of $\mu -\tau$ symmetric neutrino mass models, viz. Tribimaximal Mixing (TBM), Hexagonal Mixing (HM) and Golden Ratio Mixing (GRM) respectively. The required correction to generate a non vanishing reactor mixing angle ${\theta }_{13}$ is obtained from the perturbation matrix, type II seesaw mass term in our case. We studied the new physics contributions to NDBD and baryogenesis ignoring the left-right gauge boson mixing and the heavy-light neutrino mixing, keeping mass of the gauge bosons and scalars to be around TeV and studied the effects of the new physics contributions on the effective mass, NDBD half life and cosmological BAU and compared with the values imposed by experiments. We basically tried to find the leading order contributions to NDBD and BAU, coming from type I or type II seesaw in our work.

   hep-ph1 citation
8. 08*

   The Dark $L_{\mu }-L_{\tau }$ Rises via Kinetic Mixing

   Giorgio Arcadi🇩🇪 · Thomas Hugle🇩🇪 · Farinaldo S. Queiroz🇧🇷

   We investigate the dark matter phenomenology of a Dirac fermion together with kinetic mixing in the context of an $L_{\mu }-L_{\tau }$ model. We analyze which part of the parameter space can provide a viable dark matter candidate and explain the B-decay anomaly, while obeying current data. Although the allowed region of parameter space, satisfying these requirements, is still large at the moment, future direct detection experiments like XENONnT and DARWIN will, in case of null results, significantly strengthen the limits and push the model to a corner of the parameter space.

   hep-phPLB(2018)·73 citations
9. 09*

   Pure glueball states in a Light-Front holographic approach

   Matteo Rinaldi🇪🇸 · Vicente Vento🇪🇸

   A phenomenological analysis of the scalar glueball and scalar meson spectra is carried out by using the AdS/QCD framework in the bottom-up approach. The resulting spectra are in good agreement for glueballs with lattice QCD results and for mesons with PDG data. We make use of the relation between the mode functions in AdS/QCD and the wave functions in Light-Front $QCD$ to discuss the mixing of glueballs and mesons. The results of our investigation point out that above 2 GeV scalar particles will appear in almost degenerate pairs of unmixed glueball and mesons states leading to an interesting phenomenology whereby gluon dynamics could be well investigated.

   hep-phJ.Phys.G(2020)·20 citations
10. 10*

    Vector tetraquark state candidates: $Y(4260/4220)$, $Y(4360/4320)$, $Y(4390)$ and $Y(4660/4630)$

    Zhi-Gang Wang🇨🇳

    In this article, we construct the $C\otimes {\gamma }_{\mu }C$ and $C{\gamma }_5\otimes {\gamma }_5{\gamma }_{\mu }C$ type currents to interpolate the vector tetraquark states, then carry out the operator product expansion up to the vacuum condensates of dimension-10 in a consistent way, and obtain four QCD sum rules. In calculations, we use the formula $\mu =\sqrt{M_Y^2-(2{\mathbb{M}}_c{)}^2}$ to determine the optimal energy scales of the QCD spectral densities, moreover, we take the experimental values of the masses of the $Y(4260/4220)$, $Y(4360/4320)$, $Y(4390)$ and $Y(4660/4630)$ as input parameters and fit the pole residues to reproduce the correlation functions at the QCD side. The numerical results support assigning the $Y(4660/4630)$ to be the $C\otimes {\gamma }_{\mu }C$ type vector tetraquark state $c\bar{c}s\bar{s}$, assigning the $Y(4360/4320)$ to be $C{\gamma }_5\otimes {\gamma }_5{\gamma }_{\mu }C$ type vector tetraquark state $c\bar{c}q\bar{q}$, and disfavor assigning the $Y(4260/4220)$ and $Y(4390)$ to be the pure vector tetraquark states.

    hep-phEPJC(2018)·40 citations
11. 11*

    Neutrino oscillations and exact eigenstates in magnetic field

    Artem Popov🇷🇺 · Alexander Studenikin🇷🇺

    We further develop a recently proposed new approach to the description of the relativistic neutrino flavour ${\nu }_e^L\leftrightarrow {\nu }_{\mu }^L$, spin ${\nu }_e^L\leftrightarrow {\nu }_e^R$ and spin-flavour ${\nu }_e^L\leftrightarrow {\nu }_{\mu }^R$ oscillations in a constant magnetic field that is based on the use of the exact neutrino stationary states in the magnetic field. The neutrino flavour, spin and spin-flavour oscillations probabilities are calculated accounting for the whole set of possible conversions between four neutrino states. In general, the obtained expressions for the neutrino oscillations probabilities exhibit new inherent features in the oscillation patterns. It is shown, in particular, that: 1) in the presence of the transversal magnetic field for a given choice of parameters (the energy and magnetic moments of neutrinos and the strength of the magnetic field) the amplitude of the flavour oscillations ${\nu }_e^L\leftrightarrow {\nu }_{\mu }^L$ at the vacuum frequency is modulated by the magnetic field frequency, 2) the neutrino spin oscillation probability (without change of the neutrino flavour) exhibits the dependence on the mass square difference $\Delta m^2$.

    hep-ph11 citations
12. 12*

    Multiplicity Dependence of Charged Particle, $\varphi$ Meson and Multi-strange Particle Productions in p+p Collisions at $\sqrt{\mathrm{s}}$ = 200 GeV with PYTHIA Simulation

    Shenghui Zhang🇨🇳 · Long Zhou🇨🇳 · Yifei Zhang🇨🇳 · Mingwei Zhang🇨🇳 · Cheng Li🇨🇳 · Ming Shao🇨🇳 · Yongjie Sun🇨🇳 · Zebo Tang🇨🇳

    We report the multiplicity dependence of charged particle productions for ${\pi }^{\pm }$, $K^{\pm }$, $p$, $\overline{p}$ and $\varphi$ meson at $|y|<1.0$ in p+p collisions at $\sqrt{\mathrm{s}}$ = 200 GeV with $\mathrm{PYTHIA}$ simulation. The impact of parton multiple interactions and gluon contributions is studied and found to be possible sources of the particle yields splitting as a function of $p_T$ with respect to multiplicity. No obvious particle species dependence for the splitting is observed. The multiplicity dependence on ratios of $K^{-}/{\pi }^{-}$, $K^{+}/{\pi }^{+}$, $\overline{p}/{\pi }^{-}$, $p/{\pi }^{+}$ and $\Lambda /K_s^0$ in mid-rapidity in p+p collisions is found following the similar tendency as that in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV from RHIC, which heralds the similar underlying initial production mechanisms despite the differences in the initial colliding systems.

    hep-phnucl-thNucl.Sci.Tech.(2018)·8 citations
13. 13*

    Aspects of the pseudo Chiral Magnetic Effect in 2D Weyl-Dirac Matter

    Ana Julia Mizher🇧🇷 · Saul Hernandez-Ortiz🇲🇽 · Alfredo Raya🇲🇽 · Cristian Villavicencio🇨🇱

    A connection is established between the continuum limit of the low-energy tight-binding description of graphene immersed in an in-plane magnetic field and the Chiral Magnetic Effect in Quantum Chromodynamics. A combination of mass gaps that explicitly breaks the equivalence of the Dirac cones, favoring an imbalance of pseudo-chiralities, is the essential ingredient to generate a non-dissipative electric current along the external field. Currents, number densities and condensates generated from this setup are investigated for different hierarchies of the energy scales involved.

    hep-phcond-mat.mes-hallEPJC(2018)·11 citations
14. 14*

    Production of ${\Lambda }_c$ baryons at the LHC within the $k_T$-factorization approach and independent parton fragmentation picture

    Rafal Maciula🇵🇱 · Antoni Szczurek🇵🇱

    We calculate cross section for production of $D$ mesons and ${\Lambda }_c$ baryons in proton-proton collisions at the LHC. The cross section for production of $c\bar{c}$ pairs is calculated within $k_T$-factorization approach with the Kimber-Martin-Ryskin unintegrated gluon distributions obtained on the basis of modern collinear gluon distribution functions. We show that our approach well describes the $D^0$, $D^{+}$ and $D_s$ experimental data. We try to understand recent ALICE and LHCb data for ${\Lambda }_c$ production with the $c\to {\Lambda }_c$ independent parton fragmentation approach. The Peterson fragmentation functions are used. The $f_{c\to {\Lambda }_c}$ fragmentation fraction and ${\epsilon }_c^{\Lambda }$ parameter for $c\to {\Lambda }_c$ are varied. As a control plot we show transverse momentum distribution of different species of $D$ mesons assuming standard values of the $f_{c\to D}$ fragmentation fractions known from the literature. The fraction $f_{c\to {\Lambda }_c}$ neccessary to describe the ALICE data is much larger than the average value obtained from $e^{+}{e}^{-}$ or $ep$ experiments. No drastic modification of the shape of fragmentation function is allowed by the new ALICE and LHCb data for ${\Lambda }_c$ production. We also discuss a possible dependence of the ${\Lambda }_c/D^0$ baryon-to-meson ratio on rapidity and transverse momentum as seems observed recently by the ALICE and LHCb collaborations. Three different effects are considered: the value of ${\epsilon }_c^{\Lambda }$ parameter in Peterson fragmentation function for $c\to {\Lambda }_c$, a kinematical effect related to the hadronization prescription and a possible feed-down from higher charmed-baryon excitations. It seems very difficult, if not impossible, to understand the ALICE data within the considered independent parton fragmentation scheme.

    hep-phPRD(2018)·28 citations
15. 15*

    Predictions of Angular Observables for ${\bar{B}}_s\to K^{\ast }\ell \ell$ and $\bar{B}\to \rho \ell \ell$ in Standard Model

    Bharti Kindra🇮🇳 · Namit Mahajan🇮🇳

    Exclusive semileptonic decays based on $b\to s$ transitions have been attracting a lot of attention as some angular observables deviate significantly from the Standard Model (SM) predictions in specific $q^2$ bins. B meson decays induced by other Flavor Changing Neutral Current (FCNC), $b\to d$, can also offer a probe to new physics with an additional sensitivity to the weak phase in Cabibbo-Kobayashi-Masakawa (CKM) matrix. We provide predictions for angular observables for $b\to d$ semileptonic transitions, namely ${\bar{B}}_s\to K^{\ast }{\ell }^{+}{\ell }^{-}$, ${\bar{B}}^0\to {\rho }^0{\ell }^{+}{\ell }^{-}$, and their CP-conjugated modes. For ${\bar{B}}^0\to {\rho }^0{\ell }^{+}{\ell }^{-}$ mode, $B^0-{\bar{B}}^0$ mixing effects have been included and predictions are made for Belle and LHCb separately. Study of these decay modes will be useful in its own right and to understand the pattern of deviations in $b\to s$ transitions.

    hep-phhep-exPRD(2018)·17 citations
16. 16*

    Soft-Photon Corrections to $\bar{B}\to D{\tau }^{-}{\bar{\nu }}_{\tau }$ Relative to $\bar{B}\to D{\mu }^{-}{\bar{\nu }}_{\mu }$

    Stefan de Boer🇩🇪 · Teppei Kitahara🇩🇪 · Ivan Nisandzic🇩🇪

    We evaluate long-distance electromagnetic (QED) contributions to $\bar{B}{}^0\to D^{+}{\tau }^{-}{\bar{\nu }}_{\tau }$ and $B^{-}\to D^0{\tau }^{-}{\bar{\nu }}_{\tau }$ relative to $\bar{B}{}^0\to D^{+}{\mu }^{-}{\bar{\nu }}_{\mu }$ and $B^{-}\to D^0{\mu }^{-}{\bar{\nu }}_{\mu }$, respectively, in the standard model. We point out that the QED corrections to the ratios $R(D^{+})$ and $R(D^0)$ are not negligible, contrary to the expectation that radiative corrections are almost canceled out in the ratio of the two branching fractions. The reason is that long-distance QED corrections depend on the masses and relative velocities of the daughter particles. We find that theoretical predictions for $R(D^{+}{)}^{\tau /\mu }$ and $R(D^0{)}^{\tau /\mu }$ can be amplified by $\sim 4\%$ and $\sim 3\%$, respectively, for the soft-photon energy cut in range $20$-$40$ MeV.

    hep-phhep-exPRL(2018)·55 citations
17. 17*

    Neutrino tomography of the Earth

    Andrea Donini🇪🇸 · Sergio Palomares-Ruiz (U. Valencia, IFIC)🇪🇸 · Jordi Salvado (U. Valencia, IFIC and ICC, Barcelona U.)🇪🇸

    Cosmic-ray interactions with the nuclei of the Earth's atmosphere produce a flux of neutrinos in all directions with energies extending above the TeV scale. However, the Earth is not a fully transparent medium for neutrinos with energies above a few TeV. At these energies, the charged-current neutrino-nucleon cross section is large enough so that the neutrino mean-free path in a medium with the Earth's density is comparable to the Earth's diameter. Therefore, when neutrinos of these energies cross the Earth, there is a non-negligible probability for them to be absorbed. Since this effect depends on the distance traveled by neutrinos and on their energy, studying the zenith and energy distributions of TeV atmospheric neutrinos passing through the Earth offers an opportunity to infer the Earth's density profile. Here we perform an Earth tomography with neutrinos using actual data, the publicly available one-year through-going muon sample of the atmospheric neutrino data of the IceCube neutrino telescope. We are able to determine the mass of the Earth, its moment of inertia, the mass of the Earth's core and to establish the core is denser than the mantle, using weak interactions only, in a way completely independent from gravitational measurements. Our results confirm that this can be achieved with current neutrino detectors. This method to study the Earth's internal structure, complementary to the traditional one from geophysics based on seismological data, is starting to provide useful information and it could become competitive as soon as more statistics is available thanks to the current and larger future neutrino detectors.

    hep-phastro-ph.HENat.Phys.(2019)·76 citations
18. 18*

    Linear stability analysis of collective neutrino oscillations without spurious modes

    Taiki Morinaga🇯🇵 · Shoichi Yamada🇯🇵

    Collective neutrino oscillations are induced by the presence of neutrinos themselves. As such they are intrinsically nonlinear phenomena and are much more complex than linear counterparts such as the vacuum or MSW oscillations. They obey integro-differential equations, numerical solutions of which are also very challenging. If one focuses on the onset of the collective oscillations, on the other hand, the equations can be linearized and the technique of linear analysis can be employed. Unfortunately, however, it is well known that such an analysis, when applied with discretizations of continuous angular distributions, suffers from the appearance of so-called spurious modes, unphysical eigenmodes of the discretized linear equations. In this paper, we analyze in detail the origin of these unphysical modes and present a simple solution to this annoying problem. We have found that the spurious modes originate from the artificial production of pole singularities instead of a branch cut in the Riemann surface by the discretizations. The branching point singularities in the Riemann surface for the original undiscretized equations can be recovered by approximating the angular distributions with polynomials and then performing the integrals analytically. We demonstrate for some examples that this simple prescription removes the spurious modes indeed. We also propose an even simpler method: a piecewise linear approximation to the angular distribution. It is shown that the same methodology is applicable to the multi-energy case as well as to the dispersion relation approach that was proposed very recently.

    hep-phastro-ph.HEPRD(2018)·35 citations
19. 19*

    Dark matter constraints from dwarf galaxies: a data-driven analysis

    Francesca Calore🇫🇷 · Pasquale D. Serpico🇫🇷 · Bryan Zaldivar🇫🇷

    Dwarf galaxies represent a powerful probe of annihilating dark matter particle models, with gamma-ray data setting some of the best bounds available. A major issue in improving over existing constraints consists in the limited knowledge of the astrophysical background (mostly diffuse photons, but also unresolved sources). Perhaps more worrisome, several approaches in the literature suffer of the difficulty of assessing the systematic error due to background mis-modelling. Here we propose a data-driven method to estimate the background at the dwarf position and its uncertainty, relying on an appropriate use of the whole-sky data, via an optimisation procedure of the interpolation weights. While this article is mostly methodologically oriented, we also report the bounds based on latest Fermi-LAT data and updated information for J-factors for both isolated and stacked dwarfs. Our results are very competitive with the Fermi-LAT ones, while being derived with a more general and flexible method. We discuss the impact of profiling over the J-factor as well as over the background probability distribution function, with the latter resulting for instance crucial in drawing conclusions of compatibility with DM interpretations of the so-called Galactic Centre Excess.

    ↳ astro-ph.HEastro-ph.IMhep-phJCAP(2018)·61 citations
20. 20*

    Observational constraints on the tilted flat-XCDM and the untilted nonflat XCDM dynamical dark energy inflation parameterizations

    Chan-Gyung Park🇰🇷 · Bharat Ratra🇺🇸

    We constrain tilted spatially-flat and untilted nonflat XCDM dynamical dark energy inflation parameterizations using Planck 2015 cosmic microwave background (CMB) anisotropy data and recent baryonic acoustic oscillations distance measurements, Type Ia supernovae data, Hubble parameter observations, and growth rate measurements. Inclusion of the four non-CMB data sets results in a significant strengthening of the evidence for nonflatness in the nonflat XCDM model from 1.1$\sigma$ for the CMB data alone to 3.4$\sigma$ for the full data combination. In this untilted nonflat XCDM case the data favor a spatially-closed model in which spatial curvature contributes a little less than a percent of the current cosmological energy budget; they also mildly favor dynamical dark energy over a cosmological constant at 1.2$\sigma$. These data are also better fit by the flat-XCDM parameterization than by the standard $\Lambda$CDM model, but only at 0.3$\sigma$ significance. Current data is unable to rule out dark energy dynamics. The nonflat XCDM parameterization is compatible with the Dark Energy Survey limits on the present value of the rms mass fluctuations amplitude (${\sigma }_8$) as a function of the present value of the nonrelativistic matter density parameter (${\Omega }_m$), however it does not provide as good a fit to the higher multipole CMB temperature anisotropy data as does the standard tilted flat-$\Lambda$CDM model. A number of measured cosmological parameter values differ significantly when determined using the tilted flat-XCDM and the nonflat XCDM parameterizations, including the baryonic matter density parameter and the reionization optical depth.

    ↳ astro-ph.COgr-qchep-phhep-thAstrophys.Space Sci.(2019)·92 citations
21. 21*

    Theoretical study of the Lambda(1405) resonance in Xi_b^0 -> D^0 pi Sigma decay

    Kenta Miyahara🇯🇵 · Tetsuo Hyodo🇯🇵

    We study the mechanism of the weak decay process of Xi_b^0 into D^0 with a meson-baryon pair. It is shown that the dominant component of the prompt weak decay produces the meson-baryon pair with the spectator strange quark being transferred to the baryon, so that the Kbar N channel is absent. Subsequent final state interaction then reflects the pi Sigma originated Lambda(1405) formation amplitude, which has been difficult to access in previous experimental studies. We predict the line shapes of the pi Sigma invariant mass distribution using a realistic chiral meson-baryon amplitude for the final state interaction. It is shown that the interference between the direct and the rescattering contributions can strongly distort the peak structure of the Lambda(1405) in the mass distribution. This indicates the necessity of a detailed investigation of the reaction mechanism in order to extract the Lambda(1405) property in the pi Sigma mass distribution.

    ↳ nucl-thhep-phPRC(2018)·11 citations
22. 22*

    Decaying warm dark matter and structure formation

    Jui-Lin Kuo🇹🇼 · Massimiliano Lattanzi🇮🇹 · Kingman Cheung🇹🇼 · José W. F. Valle🇪🇸

    We examine the cosmology of warm dark matter (WDM), both stable and decaying, from the point of view of structure formation. We compare the matter power spectrum associated to WDM masses of 1.5 keV and 0.158 keV, with that expected for the stable cold dark matter $\Lambda$CDM$\equiv$SCDM paradigm, taken as our reference model. We scrutinize the effects associated to the warm nature of dark matter, as well as the fact that it decays. The decaying warm dark matter (DWDM) scenario is well-motivated, emerging in a broad class of particle physics theories where neutrino masses arise from the spontaneous breaking of a continuous global lepton number symmetry. The majoron arises as a Nambu-Goldstone boson, and picks up a mass from gravitational effects, that explicitly violate global symmetries. The majoron necessarily decays to neutrinos, with an amplitude proportional to their tiny mass, which typically gives it cosmologically long lifetimes. Using N-body simulations we show that our DWDM picture leads to a viable alternative to the $\Lambda$CDM scenario, with predictions that can differ substantially on small scales.

    ↳ astro-ph.COhep-phJCAP(2018)·17 citations
23. 23*

    Distribution of Stress Tensor around Static Quark--Anti-Quark from Yang-Mills Gradient Flow

    Ryosuke Yanagihara🇯🇵 · Takumi Iritani🇯🇵 · Masakiyo Kitazawa🇯🇵 · Masayuki Asakawa🇯🇵 · Tetsuo Hatsuda🇯🇵

    The spatial distribution of the stress tensor around the quark--anti-quark ($Q\bar{Q}$) pair in SU(3) lattice gauge theory is studied. The Yang-Mills gradient flow plays a crucial role to make the stress tensor well-defined and derivable from the numerical simulations on the lattice. The resultant stress tensor with a decomposition into local principal axes shows, for the first time, the detailed structure of the flux tube along the longitudinal and transverse directions in a gauge invariant manner. The linear confining behavior of the $Q\bar{Q}$ potential at long distances is derived directly from the integral of the local stress tensor.

    ↳ hep-lathep-phnucl-thPLB(2019)·45 citations
24. 24*

    Higgs boson measurements and extended scalar sector searches in fermionic final states

    Teresa Lenz🇩🇪

    Since the discovery of the Higgs boson in the year 2012, the CMS experiment continuously makes use of a variety of final states to measure the properties of the Higgs boson, as well as to search for it in final states where the discovery could not yet be established. This article concentrates on Higgs searches in fermionic final states including a search for the Standard Model Higgs boson in the $H\to b\overline{b}$ channel. Furthermore, three different searches for Higgs bosons beyond the Standard Model are presented. These comprise two searches for heavy neutral Higgs bosons and one search for a heavy charged Higgs boson, all of them exploiting final states with tau leptons.

    ↳ hep-exhep-phPoS(2018)·0 citations
25. 25*

    The diagrammatic coaction and the algebraic structure of cut Feynman integrals

    Samuel Abreu🇩🇪 · Ruth Britto🇮🇪 · Claude Duhr🇨🇭 · Einan Gardi🇬🇧

    We present a new formula for the coaction of a large class of integrals. When applied to one-loop (cut) Feynman integrals, it can be given a diagrammatic representation purely in terms of pinches and cuts of the edges of the graph. The coaction encodes the algebraic structure of these integrals, and offers ways to extract important properties of complicated integrals from simpler functions. In particular, it gives direct access to discontinuities of Feynman integrals and facilitates a straightforward derivation of the differential equations they satisfy, which we illustrate in the case of the pentagon.

    ↳ hep-thhep-phPoS(2018)·15 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.