Wed·Oct 3, 2018Wednesday·October 3, 2018

1. 01*

   MiniBooNE, MINOS+ and IceCube data imply a baroque neutrino sector

   Jiajun Liao🇺🇸 · Danny Marfatia🇺🇸 · Kerry Whisnant🇺🇸

   The 4.8$\sigma$ anomaly in MiniBooNE data cannot be reconciled with MINOS+ and IceCube data within the vanilla framework of neutrino oscillations involving an eV-mass sterile neutrino. We show that an apparently consistent picture can be drawn if charged-current and neutral-current nonstandard neutrino interactions are at work in the 3+1 neutrino scheme. It appears that either the neutrino sector is more elaborate than usually envisioned, or one or more datasets needs revision.

   hep-phastro-ph.HEhep-exPRD(2019)·37 citations
2. 02*

   Loop corrections to dark matter direct detection in a pseudoscalar mediator dark matter model

   Tomohiro Abe🇯🇵 · Motoko Fujiwara🇯🇵 · Junji Hisano🇯🇵

   If dark matter (DM) is a fermion and its interactions with the standard model particles are mediated by pseudoscalar particles, the tree-level amplitude for the DM-nucleon elastic scattering is suppressed by the momentum transfer in the non-relativistic limit. At the loop level, on the other hand, the spin-independent contribution to the cross section appears without such suppression. Thus, the loop corrections are essential to discuss the sensitivities of the direct detection experiments for the model prediction. The one-loop corrections were investigated in the previous works. However, the two-loop diagrams give the leading order contribution to the DM-gluon effective operator ($\bar{\chi }\chi G_{\mu \nu }^a{G}^{a\mu \nu }$) and have not been correctly evaluated yet. Moreover, some interaction terms which affect the scattering cross section were overlooked. In this paper, we show the cross section obtained by the improved analysis and discuss the region where the cross section becomes large.

   hep-phhep-exJHEP(2019)·101 citations
3. 03*

   Three-body charmed baryon Decays with SU(3) flavor symmetry

   C.Q. Geng🇨🇳 · Y.K. Hsiao🇨🇳 · Chia-Wei Liu🇹🇼 · Tien-Hsueh Tsai🇹🇼

   We study the three-body anti-triplet ${\mathbf{B}}_{\mathbf{c}}\to {\mathbf{B}}_{\mathbf{n}}M{M}^{\prime }$ decays with the $SU(3)$ flavor ($SU(3{)}_f$) symmetry, where ${\mathbf{B}}_{\mathbf{c}}$ denotes the charmed baryon anti-triplet of $({\Xi }_c^0,-{\Xi }_c^{+},{\Lambda }_c^{+})$, and ${\mathbf{B}}_{\mathbf{n}}$ and $M(M^{\prime })$ represent baryon and meson octets, respectively. By considering only the S-wave $M{M}^{\prime }$-pair contributions without resonance effects, the decays of ${\mathbf{B}}_{\mathbf{c}}\to {\mathbf{B}}_{\mathbf{n}}M{M}^{\prime }$ can be decomposed into irreducible forms with 11 parameters under $SU(3{)}_f$, which are fitted by the 14 existing data, resulting in a reasonable value of ${\chi }^2/d.o.f=2.8$ for the fit. Consequently, we find that the triangle sum rule of $\mathcal{A}({\Lambda }_c^{+}\to n{\bar{K}}^0{\pi }^{+})-\mathcal{A}({\Lambda }_c^{+}\to p{K}^{-}{\pi }^{+})-\sqrt{2}\mathcal{A}({\Lambda }_c^{+}\to p{\bar{K}}^0{\pi }^0)=0$ given by the isospin symmetry holds under $SU(3{)}_f$, where $\mathcal{A}$ stands for the decay amplitude. In addition, we predict that $\mathcal{B}({\Lambda }_c^{+}\to n{\pi }^{+}{\bar{K}}^0)=(0.9\pm 0.8)\times 10^{-2}$, which is $3-4$ times smaller than the BESIII observation, indicating the existence of the resonant states. For the to-be-observed ${\mathbf{B}}_{\mathbf{c}}\to {\mathbf{B}}_{\mathbf{n}}M{M}^{\prime }$ decays, we compute the branching fractions with the $SU(3{)}_f$ amplitudes to be compared to the BESIII and LHCb measurements in the future.

   hep-phhep-exPRD(2019)·60 citations
4. 04*

   $b\to cl\nu$ anomalies in light of vector and scalar interactions

   Aritra Biswas🇮🇳

   We perform a model independent analysis of the charged current $b\to cl\nu$ anomalies under the presence of scalar and vector interactions. The analysis is carried out in two stages: (a) under the presence of both (left-handed) vector and scalar interactions and (b) under the presence of scalar interactions alone. We find that even after stringent bounds from similar quark-level processes such as $B_c\to \tau \nu$, such scenarios have the potential to explain the aforementioned anomalies. Contrary to the general notion, we show that even scalar interactions alone can explain such anomalies, provided they are complex. However, extended scalar sector models are unable to comply with these anomalies to $\sim 3\sigma$. We further illustrate our results with the help of three benchmark models corresponding to the presence of (i) both scalar and vector (ii) real scalar and (iii) complex scalar interactions.

   hep-phSpringer Proc.Phys.(2019)·0 citations
5. 05*

   Central exclusive production of $K^{+}{K}^{-}$ pairs in proton-proton collisions

   Piotr Lebiedowicz🇵🇱 · Antoni Szczurek🇵🇱 · Otto Nachtmann🇩🇪

   We discuss central exclusive diffractive production of light mesons in the reactions $pp\to pp{\pi }^{+}{\pi }^{-}$ and $pp\to pp{K}^{+}{K}^{-}$. The calculation is based on a tensor-pomeron approach. We include a purely diffractive dipion continuum, and the scalar $f_0(980)$, $f_0(1500)$, $f_0(1710)$ and tensor $f_2(1270)$, $f_2^{\prime }(1525)$ resonances decaying into pseudoscalar meson pairs. We include also photoproduction mechanisms for the nonresonant (Drell-Söding) and the $\varphi (1020)$ resonance contributions. The theoretical results are compared with existing CDF experimental data and predictions for being carried out LHC experiments are presented. The distributions in dimeson invariant mass and in a special "glueball filter variable" including the interference effects of resonance and dimeson continuum are presented.

   hep-phEPJ Web Conf.(2019)·0 citations
6. 06*

   Open-Flavour Mesons from the Angle of Bethe, Dyson, Salpeter, Schwinger, et al

   Thomas Hilger🇦🇹 · María Gómez-Rocha🇮🇹 · Andreas Krassnigg🇦🇹 · Wolfgang Lucha🇦🇹

   Recently, we completed a comprehensive investigation of a huge part of the entire meson spectrum by considering both quarkonia and open-flavour mesons by means of a single common framework which unites the homogeneous Bethe-Salpeter equation that describes mesons as quark-antiquark bound states and the Dyson-Schwinger equation that governs the full quark propagator: Adopting two (as a matter of fact, not extremely diverse) models that attempt to grasp all principal aspects of the effective strong interactions entering identically in both these equations, we derived within this unique setup, for all mesons analysed, their masses and leptonic decay constants as well as, for the pseudoscalar ones among these mesons, their in-hadron condensates. Here, as a kind of promotion or teaser, we give but a few examples of the resulting collections of data, laying the main emphasis on the dependence of our insights on the effective-interaction model underlying all such outcomes.

   hep-phhep-exnucl-thPoS(2018)·1 citation
7. 07*

   Electric dipole moments: a theory overview

   Emanuele Mereghetti🇺🇸

   Electric dipole moments are extremely sensitive probes of physics beyond the Standard Model. A vibrant experimental program is in place, with the goal of improving existing bounds on the electron and neutron electric dipole moments by one or two orders of magnitude, while testing new ideas for the measurement of electric dipole moments of light ions, such as the proton and the deuteron, at a comparable level. The success of this program, and its implications for physics beyond the Standard Model, relies on the precise calculation of the electric dipole moments in terms of the couplings of CP-violating operators induced by beyond-the-Standard-Model physics. In light of the nonperturbative nature of both QCD at low energy and of the nuclear interactions, these calculations have proven difficult, and are affected by large theoretical uncertainties. In this talk I will review the progress that has been achieved on different aspects of the calculation of hadronic and nuclear EDMs, the challenges that remain to be faced, and the implications for our understanding of physics beyond the Standard Model.

   hep-ph6 citations
8. 08*

   On the relationship between gauge dependence and IR divergences in the $\hslash$-expansion of the effective potential

   Andreas Ekstedt🇸🇪 · Johan Löfgren🇸🇪

   Perturbative calculations of the effective potential evaluated at a broken minimum, $V_{\text{min}}$, are plagued by difficulties. It is hard to get a finite and gauge invariant result for $V_{\text{min}}$. In fact, the methods proposed to deal with gauge dependence and IR divergences are orthogonal in their approaches. Gauge dependence is dealt with through the $\hslash$-expansion, which establishes and maintains a strict loop-order separation of terms. On the other hand, IR divergences seem to require a resummation that mixes the different loop orders. In this paper we test these methods on Fermi gauge Abelian Higgs at two loops. We find that the resummation procedure is not capable of removing all divergences. Surprisingly, the $\hslash$-expansion seems to be able to deal with both the divergences and the gauge dependence. In order to isolate the physical part of $V_{\text{min}}$, we are guided by the separation of scales that motivated the resummation procedure; the key result is that only hard momentum modes contribute to $V_{\text{min}}$.

   hep-phhep-thJHEP(2019)·15 citations
9. 09*

   Boson Star from Repulsive Light Scalars and Gravitational Waves

   Djuna Croon🇨🇦 · JiJi Fan🇺🇸 · Chen Sun🇨🇳

   We study properties of boson stars consisting of ultra-light scalar dark matter with repulsive self-interactions. We investigate the origin of the maximum mass of spherically symmetric stable stars which emerges only when solving the full equations of motion in curved space-time, but not when solving the approximated Schrödinger-Newton equations. When the repulsion is weak, the backreaction of the curvature on the scalars acts as an additional source of attraction and can overcome the repulsion, resulting in a maximum star mass and compactness. We also point out that the potential in a UV completed particle physics model of light scalar dark matter is generally more complicated than the widely used ${\varphi }^4$ interaction. Additional interactions beyond ${\varphi }^4$ in the potential can dramatically change the properties of boson stars as well as modify the prospect of LIGO gravitational wave detection for binary mergers of boson stars.

   hep-phastro-ph.COastro-ph.GAgr-qcJCAP(2019)·50 citations
10. 10*

    A New Probe of Dark Matter-Induced Fifth Force with Neutron Star Inspirals

    Han Gil Choi🇰🇷 · Sunghoon Jung🇰🇷

    A light scalar dark matter (DM) is allowed in a wide range of the mass and interaction types. We show that the light scalar DM may be probed in a new way from final years of neutron-star (NS) binary inspirals. If the DM interacts with the neutron, its long wave coherence in the background can induce the time-oscillating mass shift, to which the binary inspiral is inherently sensitive. But the sensitivity is found to be significantly enhanced by a large number of gravitational-wave (GW) cycles during year-long highest-frequency measurements in the broadband $f\simeq 0.01-1000$ Hz. The future broadband detector networks including LIGO-band detectors can probe unconstrained parameter space of the light scalar DM.

    hep-phastro-ph.COgr-qcPRD(2019)·23 citations
11. 11*

    Charged Planckian Interacting Dark Matter

    Mathias Garny🇩🇪 · Andrea Palessandro🇩🇰 · McCullen Sandora🇺🇸 · Martin S. Sloth🇩🇰

    A minimal model of Cold Dark Matter (CDM) is a very massive particle with only gravitational interactions, also called Planckian Interacting Dark Matter (PIDM). Here we consider an extension of the PIDM framework by an unbroken $U(1)$ gauge symmetry under which the PIDM is charged, but remains only gravitationally coupled to the Standard Model (SM). Contrary to "hidden charged dark matter", the charged PIDM never reaches thermal equilibrium with the SM. The dark sector is populated by freeze-in via gravitational interactions at reheating. If the dark fine-structure constant ${\alpha }_D$ is larger than about $10^{-3}$, the dark sector thermalizes within itself, and the PIDM abundance is further modified by freeze-out in the dark sector. Interestingly, this largely reduces the dependence of the final abundance on the reheating temperature, as compared to an uncharged PIDM. Thermalization within the dark sector is driven by inelastic radiative processes, and affected by the Landau-Pomeranchuk-Migdal (LPM) effect. The observed CDM abundance can be obtained over a wide mass range from the weak to the GUT scale, and for phenomenologically interesting couplings ${\alpha }_D\sim 10^{-2}$. Due to the different thermal history, the charged PIDM can be discriminated from "hidden charged dark matter" by more precise measurements of the effective number of neutrino species $N_{\mathrm{eff}}$.

    hep-phastro-ph.COastro-ph.HEhep-thJCAP(2019)·42 citations
12. 12*

    $\Delta \left(27\right)$ flavor singlet-triplet Higgs model for fermion masses and mixings

    A. E. Cárcamo Hernández🇨🇱 · Juan Carlos Gómez-Izquierdo🇲🇽 · Sergey Kovalenko🇨🇱 · M. Mondragón🇲🇽

    We propose a multiscalar singlet extension of the singlet-triplet Higgs model capable of explaining the SM fermion mass spectrum and mixing parameters. Our model is based on the $\Delta \left(27\right)$ family symmetry, supplemented by cyclic symmetries, which are spontaneously broken thus yielding the observed hierarchy of the SM charged fermion masses and quark mixing angles. The masses of the light active neutrinos are produced by type-II seesaw mechanism mediated by the neutral component of the $SU(2{)}_L$ scalar triplet. The model symmetries lead to the extended Gatto-Sartori-Tonin relations between the quark masses and mixing angles.

    hep-phNPB(2019)·20 citations
13. 13*

    Searches for gamma-ray lines and `pure WIMP' spectra from Dark Matter annihilations in dwarf galaxies with H.E.S.S

    H.E.S.S. Collaboration: H. Abdalla🇿🇦 · F. Aharonian🇩🇪 · F. Ait Benkhali🇩🇪 · E.O. Angüner🇫🇷 · M. Arakawa🇯🇵 · C. Arcaro🇿🇦 · C. Armand🇫🇷 · M. Arrieta🇫🇷 · M. Backes🇳🇦 · M. Barnard🇿🇦 · Y. Becherini🇸🇪 · J. Becker Tjus🇩🇪 and 223 other authors

    Dwarf spheroidal galaxies are among the most promising targets for detecting signals of Dark Matter (DM) annihilations. The H.E.S.S. experiment has observed five of these systems for a total of about 130 hours. The data are re-analyzed here, and, in the absence of any detected signals, are interpreted in terms of limits on the DM annihilation cross section. Two scenarios are considered: i) DM annihilation into mono-energetic gamma-rays and ii) DM in the form of pure WIMP multiplets that, annihilating into all electroweak bosons, produce a distinctive gamma-ray spectral shape with a high-energy peak at the DM mass and a lower-energy continuum. For case i), upper limits at 95\% confidence level of about $⟨\sigma v⟩\lesssim 3\times 10^{-25}$ cm${}^3$ s${}^{-1}$ are obtained in the mass range of 400 GeV to 1 TeV. For case ii), the full spectral shape of the models is used and several excluded regions are identified, but the thermal masses of the candidates are not robustly ruled out.

    ↳ astro-ph.HEhep-exhep-phJCAP(2018)·82 citations
14. 14*

    Event by event fluctuations of the source shape: implications for the Levy shape, and Event Shape Sorting

    Boris Tomasik🇸🇰 · Jakub Cimerman🇨🇿

    In the first part of this contribution we show that the Levy stable shape of the correlation function can be caused by averaging of the measured correlation functions over a large number of events. In the second part it is demonstrated how a sample of events sorted by Event Shape Sorting technique exhibits different azimuthal dependence of correlation radii in each event class.

    ↳ nucl-thhep-phnucl-ex0 citations
15. 15*

    $N$-point functions of strongly coupled fluids dual to generalized higher-derivative theories of gravity

    M.M.W. Shawa🇿🇦 · A.J.M. Medved🇿🇦

    We calculate the connected stress-tensor correlation functions that are dual to a certain class of graviton scattering amplitudes in an asymptotically anti-de Sitter, black brane spacetime. This is a continuation of a previous study in which one-particle-irreducible amplitudes were calculated for arbitrarily higher-derivative gravity in a particular kinetic regime of high energies and large scattering angles. The utility of this regime is twofold: It is particularly well suited for translating scattering amplitudes into the language of the gauge theory and it emphasizes the contributions from higher-derivative corrections (which would otherwise be perturbatively suppressed). Using the new results, we show how it could be possible to identify, experimentally, the gravitational dual to a strongly coupled fluid such as the quark-gluon plasma.

    ↳ hep-thgr-qchep-phPRD(2018)·0 citations
16. 16*

    Variational approach to $N$-body interactions in finite volume

    Peng Guo🇺🇸 · Michael Döring🇺🇸 · Adam P. Szczepaniak🇺🇸

    We explore variational approach to the finite-volume $N$-body problem. The general formalism for N non-relativistic spinless particles interacting with periodic pair-wise potentials yields N-body secular equations. The solutions depend on the infinite-volume N-body wave functions. Given that the infinite-volume N-body dynamics may be solved by the standard Faddeev approach, the variational N-body formalism can provide a convenient numerical framework for finding discrete energy spectra in periodic lattice structures.

    ↳ hep-lathep-phPRD(2018)·64 citations
17. 17*

    Quantum decay in renormalizable field theories: quasiparticle formation, Zeno and anti-Zeno effects

    Daniel Boyanovsky🇺🇸

    In a renormalizable theory the survival probability of an unstable quantum state features divergences as a consequence of the rapid growth of the density of states with energy. Introducing a high energy cutoff $\Lambda$, the transient dynamics during a time scale $\simeq 1/\Lambda$ describes the renormalization of the bare into a `quasiparticle' state which decays on longer time scales. During this early transient the decay law features Zeno behavior $e^{-(t/t_Z{)}^2}$ with the Zeno time-scale $t_Z\propto 1/{\Lambda }^{3/2}$. We introduce a dynamical renormalization framework that allows to separate consistently the dynamics of formation of the quasiparticle state and its decay on longer time scales by introducing a renormalization time scale along with alternative `schemes'. The survival probability obeys a renormalization group equation with respect to this scale. We find a transient \emph{suppression} of the decay law for large Lorentz factor as a consequence of the narrowing of the phase space for decay different from the usual time dilation. In presence of higher mass thresholds, the energy uncertainty associated with transient dynamics leads to an \emph{anti Zeno enhancement} with a transient acceleration of the decay into \emph{heavier particles}. There remains memory of the transient effects in the survival probability even at long time. We discuss possible consequences of these effects in cosmology.

    ↳ hep-thcond-mat.otherhep-phquant-phAnnals Phys.(2019)·11 citations
18. 18*

    Short Range Interactions in the Hydrogen Atom

    A. D. Bermudez Manjarres🇨🇴 · D. Bedoya Fierro🇨🇴 · N. G. Kelkar🇨🇴 · M. Nowakowski🇨🇴

    In calculating the energy corrections to the hydrogen levels we can identify two different types of modifications of the Coulomb potential $V_C$, with one of them being the standard quantum electrodynamics corrections, $\delta V$, satisfying $\left|\delta V\right|\ll \left|V_C\right|$ over the whole range of the radial variable $r$. The other possible addition to $V_C$ is a potential arising due to the finite size of the atomic nucleus and as a matter of fact, can be larger than $V_C$ in a very short range. We focus here on the latter and show that the electric potential of the proton displays some undesirable features. Among others, the energy content of the electric field associated with this potential is very close to the threshold of $e^{+}{e}^{-}$ pair production. We contrast this large electric field of the Maxwell theory with one emerging from the non-linear Euler-Heisenberg theory and show how in this theory the short range electric field becomes smaller and is well below the pair production threshold.

    ↳ physics.atom-phhep-phEur.Phys.J.D(2018)·2 citations
19. 19*

    Effect of the Quark-Gluon Vertex on Dynamical Chiral Symmetry Breaking

    M. Atif Sultan🇵🇰 · Khépani Raya🇨🇳 · Faisal Akram🇵🇰 · Adnan Bashir🇲🇽 · Bilal Masud🇵🇰

    In this work, we investigate how the details of the quark-gluon interaction vertex affect the quantitative description of chiral symmetry breaking through the gap equation for quarks. We start from two gluon propagator models widely used in literature and constructed in direct connection with our gradually improved understanding of infrared quantum chromodynamics coupled with its exact one-loop limit. The gap equation is then solved by employing a variety of vertex \emph{Ansätze}, which have been constructed in order to implement some of the key aspects of quantum chromodynamics, namely, multiplicative renormalizability of the quark propagator, gauge invariance, matching with perturbation theory in the weak coupling regime, independence from unphysical kinematic singularities as well as manifestly correct transformation properties under charge conjugation and parity operations. On general grounds, all truncation schemes exhibit the same qualitative and quantitative pattern of chiral symmetry breaking, ensuring the overall robustness of this approach and its potentially reliable description of the hadron spectrum and properties.

    ↳ nucl-thhep-phPRD(2021)·25 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.