Thu·Feb 16, 2017Thursday·February 16, 2017

1. 01*

   Dish Antenna Searches for WISPy Dark Matter: Directional Resolution Small Mass Limitations

   Joerg Jaeckel🇩🇪 · Stefan Knirck🇩🇪

   Hidden photon and axion-like dark matter may be detected using spherical reflective surfaces such as dish antenna setups converting some of the dark matter particles into photons and concentrating them on a detector. These setups may be used to perform directional searches measuring the dark matter momentum distribution. We briefly review the photon distribution one expects to detect with such an antenna and directional resolution in ray approximation. Furthermore we consider the regime $m_{DM}\lesssim (R_{sp}{v}_{DM}{)}^{-1}$ where this approximation does not hold anymore due to the photon wavelength exceeding the expected distribution widths. We discuss how this affects the expected distributions and experimental implications.

   hep-ph8 citations
2. 02*

   Generalized TMDs and the exclusive double Drell-Yan process

   Shohini Bhattacharya🇺🇸 · Andreas Metz🇺🇸 · Jian Zhou🇨🇳

   Generalized transverse momentum dependent parton distributions (GTMDs) are the most general parton correlation functions of hadrons. By considering the exclusive double Drell-Yan process it is shown for the first time how quark GTMDs can be measured. Specific GTMDs can be addressed by means of polarization observables.

   hep-phhep-exnucl-exPLB(2017)·106 citations
3. 03*

   Right-handed neutrinos: dark matter, lepton flavor violation and leptonic collider searches

   Meziane Chekkal🇩🇿 · Amine Ahriche🇩🇿 · Amine Bouziane Hammou🇩🇿 · Salah Nasri🇦🇪

   We examine lepton flavor violating (LFV) interactions for heavy right-handed neutrinos that exist in most of the standard model extensions that address dark matter (DM) and neutrino mass at the loop level. In order to probe the collider effect of these LFV interactions, we impose the assumption that the model parameters give the right values of the DM relic density and fulfill the constraints from the LFV processes ${\ell }_{\alpha }\to {\ell }_{\beta }\gamma$ and ${\ell }_{\alpha }\to 3{\ell }_{\beta }$. We also investigate the possibility of probing these interactions, and hence the right-handed neutrino, at leptonic colliders through different final state signatures.

   hep-phPRD(2017)·25 citations
4. 04*

   Dilaton EFT Framework For Lattice Data

   Thomas Appelquist🇺🇸 · James Ingoldby🇺🇸 · Maurizio Piai🇬🇧

   We develop an effective-field-theory (EFT) framework to analyze the spectra emerging from lattice simulations of a large class of confining gauge theories. Simulations of these theories, for which the light-fermion count is not far below the critical value for transition to infrared conformal behavior, have indicated the presence of a remarkably light singlet scalar particle. We incorporate this particle by including a scalar field in the EFT along with the Nambu-Goldstone bosons (NGB's), and discuss the application of this EFT to lattice data. We highlight the feature that data on the NGB's alone can tightly restrict the form of the scalar interactions. As an example, we apply the framework to lattice data for an SU(3) gauge theory with eight fermion flavors, concluding that the EFT can describe the data well.

   hep-phhep-latJHEP(2017)·104 citations
5. 05*

   Quark-gluon Vertex: A Perturbation Theory Primer and Beyond

   R. Bermudez🇲🇽 · L. Albino🇲🇽 · L.X. Gutiérrez-Guerrero🇲🇽 · M.E. Tejeda-Yeomans🇲🇽 · A. Bashir🇲🇽

   There has been growing evidence that the infrared enhancement of the form factors defining the full quark-gluon vertex plays an important role in realizing a dynamical breakdown of chiral symmetry in quantum chromodynamics, leading to the observed spectrum and properties of hadrons. Both the lattice and the Schwinger-Dyson communities have begun to calculate these form factors in various kinematical regimes of momenta involved. A natural consistency check for these studies is that they should match onto the perturbative predictions in the ultraviolet, where non-perturbative effects mellow down. In this article, we carry out a numerical analysis of the one-loop result for all the form factors of the quark-gluon vertex. Interestingly, even the one-loop results qualitatively encode most of the infrared enhancement features expected of their non-perturbative counter parts. We analyze various kinematical configurations of momenta: symmetric, on-shell and asymptotic. The on-shell limit enables us to compute anomalous chromomagnetic moment of quarks. The asymptotic results have implications for the multiplicative renormalizability of the quark propagator and its connection with the Landau-Khalatnikov-Fradkin transformations, allowing us to analyze and compare various Ans$\ddot{a}$tze proposed so far.

   hep-phhep-thnucl-thPRD(2017)·66 citations
6. 06*

   Possible hadronic molecular states composed of $S$-wave heavy-light mesons

   Ming-Zhu Liu🇨🇳 · Duo-Jie Jia🇨🇳 · Dian-Yong Chen🇨🇳

   We perform a systematical study of possible molecular states composed of the $S$ wave heavy light mesons, where the $S-D$ mixing and {$\eta -{\eta }^{\prime }$ mixing} are explicitly included. Our calculation indicates that the observed $X(3872)$ could be a loosely shallow molecular state composed of $D{\bar{D}}^{\ast }+h.c$, while neither $Z_c(3900)/Z_c(4020)$ nor $Z_b(10610)/Z_b(10650)$ is supported to be a molecule. Some observed possible molecular states are predicted, which could be searched for by further experimental measurements.

   hep-phCPC(2017)·18 citations
7. 07*

   Electron Electric Dipole Moment in Mirror Fermion Model with Electroweak Scale Non-sterile Right-handed Neutrinos

   Chia-Feng Chang🇹🇼 · P. Q. Hung🇺🇸 · Chrisna Setyo Nugroho🇹🇼 · Van Que Tran🇹🇼 · Tzu-Chiang Yuan🇹🇼

   The electric dipole moment of the electron is studied in detail in an extended mirror fermion model with the following unique features of (a) right-handed neutrinos are non-sterile and have masses at the electroweak scale, and (b) a horizontal symmetry of the tetrahedral group is used in the lepton and scalar sectors. We study the constraint on the parameter space of the model imposed by the latest ACME experimental limit on electron electric dipole moment. Other low energy experimental observables such as the anomalous magnetic dipole moment of the muon, charged lepton flavor violating processes like muon decays into electron plus photon and muon-to-electron conversion in titanium, gold and lead are also considered in our analysis for comparison. In addition to the well-known CP violating Dirac and Majorana phases in the neutrino mixing matrix, the dependence of additional phases of the new Yukawa couplings in the model is studied in detail for all these low energy observables.

   hep-phhep-exNPB(2018)·13 citations
8. 08*

   Sterile neutrino dark matter from right-handed neutrino oscillations

   Kenji Kadota🇰🇷 · Kunio Kaneta🇰🇷

   We study a scenario where sterile neutrino (either warm or cold) dark matter (DM) is produced through (nonresonant) oscillations among right-handed neutrinos (RHNs) and can constitute the whole DM in the Universe, in contrast to the conventional sterile neutrino production through its mixing with the left-handed neutrinos. The lightest RHN can be sterile neutrino DM whose mixing with left-handed neutrinos is sufficiently small while heavier RHNs can have non-negligible mixings with left-handed neutrinos to explain the neutrino masses by the seesaw mechanism. We also demonstrate that, in our scenario, the production of sterile RHN DM from the decay of a heavier RHN is subdominant compared with the RHN oscillation production due to the X-ray and small-scale structure constraints.

   hep-phastro-ph.COPRD(2018)·3 citations
9. 09*

   Testing the nature of neutrinos from four-body $\tau$ decays

   Han Yuan🇨🇳 · Yue Jiang🇨🇳 · Tian-hong Wang🇨🇳 · Qiang Li🇨🇳 · Guo-Li Wang🇨🇳

   This paper is designed to discuss four-body lepton number violating tau decay. We study the processes ${\tau }^{+}\to e^{+}{e}^{+}{\pi }^{-}{\nu }_{\tau }$ and ${\tau }^{+}\to e^{+}{e}^{+}{\pi }^{-}{\nu }_e$ to determine the nature of neutrino. The first process violates lepton number by two units which can only happen through an internal Majorana. The second one conserves lepton number but violates lepton flavor which can take place with both Majorana neutrino and Dirac neutrino. We calculate their branching ratio $Br$ and differential branching ratio $dBr/d{E}_{\pi }$ to distinguish Majorana neutrino vs. Dirac neutrino. We also propose the possibility of experiment to perform this detection.

   hep-phJ.Phys.G(2017)·14 citations
10. 10*

    Transverse structure of proton in a light-front quark-diquark model

    Tanmay Maji🇮🇳 · Dipankar Chakrabarti🇮🇳

    We present all the leading twist T-even TMDs in the light-front quark diquark model(LFQDM) and study the relations among them. The model contains both the scalar and vector diquarks with the light front wave functions modeled from the soft-wall AdS/QCD prediction. The $x-p_{\perp }^2$ factorization used in phenomenological extraction for TMDs is observed in this model. We present the results for the quark densities and the transverse shape of proton. The shape of the transversely polarized proton is shown to be non-spherical for nonzero transverse momentum. The scale evolution of both integrated and unintegrated TMDs are also presented in this paper.

    hep-phPRD(2017)·48 citations
11. 11*

    Weak Radiative Decays of the B Meson and Bounds on $M_{H^{\pm }}$ in the Two-Higgs-Doublet Model

    Mikolaj Misiak🇨🇭 · Matthias Steinhauser🇩🇪

    In a recent publication [6], the Belle collaboration updated their analysis of the inclusive weak radiative B-meson decay, including the full dataset of (772 +_ 11) x 10^6 BBbar pairs. Their result for the branching ratio is now below the Standard Model prediction [7,8], though it remains consistent with it. However, bounds on the charged Higgs boson mass in the Two-Higgs-Doublet Model get affected in a significant manner. In the so-called Model-II, the 95% C.L. lower bound on $M_{H^{\pm }}$ is now in the 570-800 GeV range, depending quite sensitively on the method applied for its determination. Our present note is devoted to presenting and discussing the updated bounds, as well as to clarifying several ambiguities that one might encounter in evaluating them. One of such ambiguities stems from the photon energy cutoff choice, which deserves re-consideration in view of the improved experimental accuracy.

    hep-phEPJC(2017)·383 citations
12. 12*

    The muon (g - 2) anomaly and a new light vector boson

    N.V.Krasnikov🇷🇺

    This mini review aims to outline the main experimental and theoretical results related with the search for a new light vector boson proposed as a solution of the muon $g-2$ anomaly. Additionally, I consider a model with infinite number of light vector bosons which can explain the anomaly, while still remaining consistent with current experimental bounds.

    hep-ph13 citations
13. 13*

    Bounds on heavy Majorana neutrinos in type-I seesaw and implications for collider searches

    Arindam Das🇰🇷 · Nobuchika Okada🇺🇸

    The neutrino masses and flavor mixings, which are missing in the Standard Model (SM), can be naturally incorporated in the type-I seesaw extension of the SM with heavy Majorana neutrinos being singlet under the SM gauge group. If the heavy Majorana neutrinos are around the electroweak scale and their mixings with the SM neutrinos are sizable, they can be produced at high energy colliders, leaving characteristic signatures with lepton-number violations. Employing the general parametrization for the neutrino Dirac mass matrix in the minimal seesaw scenario, we perform a parameter scan and identify allowed regions to satisfy a variety of experimental constraints from the neutrino oscillation data, the electroweak precision measurements and the lepton-flavor violating processes. We find that the resultant mixing parameters between the heavy neutrinos and the SM neutrinos are more severely constrained than those obtained from the current search for heavy Majorana neutrinos at the LHC. Such parameter regions can be explored at the High-Luminosity LHC and a 100 TeV pp-collider in the future.

    hep-phhep-exPLB(2017)·120 citations
14. 14*

    New constraints and discovery potential of sub-GeV dark matter with xenon detectors

    Christopher McCabe🇳🇱

    Existing xenon dark matter (DM) direct detection experiments can probe the DM-nucleon interaction of DM with a sub-GeV mass through a search for photon emission from the recoiling xenon atom. We show that LUX's constraints on sub-GeV DM, which utilise the scintillation (S1) and ionisation (S2) signals, are approximately three orders of magnitude more stringent than previous xenon constraints in this mass range, derived from the XENON10 and XENON100 S2-only searches. The new LUX constraints provide the most stringent direct detection constraints for DM particles with a mass below 0.5 GeV. In addition, the photon emission signal in LUX and its successor LZ maintain the discrimination between background and signal events so that an unambiguous discovery of sub-GeV DM is possible. We show that LZ has the potential to reconstruct the DM mass with 20% accuracy for particles lighter than 0.5 GeV.

    hep-phastro-ph.COhep-exPRD(2017)·44 citations
15. 15*

    Nucleon Matrix Elements at Physical Pion Mass and Cost Comparison

    Keh-Fei Liu🇺🇸 · Jian Liang🇺🇸 · Yi-Bo Yang🇺🇸

    We report a lattice calculation of nucleon forward matrix elements on a $48^3\times 96$ lattice at the physical pion mass and a spatial size of 5.5 fm. The $2+1$ flavor dynamical fermion configurations are generated with domain-wall fermions (DWF) and the overlap fermions are adopted for the valence quarks. The isovector $g_A^3$ and $g_S^3$, and the connected insertion part of $g_S^0$ are reported for three source-sink separations. With local current, we obtain $g_A^3=1.18(4)$ from a two-state fit. For the quark momentum fraction $⟨x{⟩}_{u-d}$, we have included smaller lattices (i.e. $24^3\times 64$ and $32^3\times 64$ lattice with pion mass at 330 and 290 MeV respectively) for a fit which includes partially quenched cases as well as finite volume and continuum corrections. A global fit with perturbative renormalization gives $⟨x{⟩}_{u-d}(\overline{MS},\mu =2\mathrm{GeV})=0.170(14)$. We made a cost comparison of calculating the nucleon matrix elements with those from the twisted mass fermion on similar sized lattice at the physical pion point and the domain-wall fermion calculation on the same DWF lattice. We also compare cost with the clover fermion calculation on similar sized lattice at about the same quark mass. The comparison shows that with several improvements, such as many-to-all correlator with grid source and low-mode substitution in the connected insertion and low-mode average in the quark loop can make the overlap as efficient as the twisted-mass and clover fermions in calculating the three-point functions. It is more efficient than the DWF. When the multi-mass feature is invoked, the overlap can be more efficient in reaching the same precision than the single mass comparison made so far.

    ↳ hep-lathep-ph1 citation
16. 16*

    Probing new physics with atmospheric neutrinos at KM3NeT-ORCA

    Joao A. B. Coelho (APC, Université Paris Diderot) (for the KM3NeT Collaboration)🇫🇷

    We present the prospects of ORCA searches for new physics phenomena using atmospheric neutrinos. Focus is given to exploiting the impact of strong matter effects on the oscillation of atmospheric neutrinos in light of expanded models, such as sterile neutrinos and non-standard interactions. In the presence of light sterile neutrinos that mix with active neutrinos, additional resonances and suppressions may occur at different energies. One may also use neutrino oscillations to probe the properties of the coherent forward scattering which may be altered by new interactions beyond the Standard Model. Preliminary studies show that ORCA would be able to probe some parameters of these models with sensitivity up to one order of magnitude better than current constraints.

    ↳ hep-exhep-phJ.Phys.Conf.Ser.(2017)·6 citations
17. 17*

    Probing the interaction between dark energy and dark matter with the parametrized post-Friedmann approach

    Xin Zhang🇨🇳

    There possibly exists some direct, non-gravitational coupling between dark energy and dark matter. This possibility should be seriously tested by using observations, which requires us to understand such a scenario from the aspects of both expansion history and growth of structure. It is found that once calculating the perturbations in the interacting dark energy (IDE) scenario, for most cases the curvature perturbation on superhorizon scales is divergent, which is a catastrophe for the IDE cosmology. We found a solution to this issue, which is to establish an effective theory to treat the dark energy perturbations totally based on the basic facts of dark energy. This scheme generalizes the parametrized post-Friedmann framework of uncoupled dark energy and can be used to cure the instability of the IDE cosmology. The whole parameter space of IDE models can henceforward be explored by observational data. The IDE scenario can thus be tested or falsified with current and future observational data by using the PPF approach. We expect that the future highly accurate observational data would offer the certain answer to the question whether there is a direct coupling between dark energy and dark matter.

    ↳ astro-ph.COgr-qchep-phhep-thSCPMA(2017)·54 citations
18. 18*

    Top Quark Physics at the High Luminosity LHC

    Patrizia Azzi🇮🇹 · Markus Cristinziani🇩🇪

    A summary of the prospects for top-quark physics at the High Luminosity LHC.

    ↳ hep-exhep-ph2 citations
19. 19*

    Working directly with probabilities in quantum field theory

    Robert Dickinson🇬🇧 · Jeff Forshaw🇬🇧 · Peter Millington🇬🇧

    We present a novel approach to computing transition probabilities in quantum field theory, which allows them to be written directly in terms of expectation values of nested commutators and anti-commutators of field operators, rather than squared matrix elements. We show that this leads to a diagrammatic expansion in which the retarded propagator plays a dominant role. As a result, one is able to see clearly how faster-than-light signalling is prevented between sources and detectors. Finally, we comment on potential implications of this approach for dealing with infra-red divergences.

    ↳ hep-thhep-phquant-phJ.Phys.Conf.Ser.(2017)·9 citations
20. 20*

    Quark model study of the $\pi N\to \pi N$ reactions up to the $N(1440)$ resonance region

    Kai-Lei Wang🇨🇳 · Li-Ye Xiao🇨🇳 · Xian-Hui Zhong🇨🇳

    A combined analysis of the reactions ${\pi }^{+}p\to {\pi }^{+}p$, ${\pi }^{-}p\to {\pi }^{-}p$ and ${\pi }^{-}p\to {\pi }^{0}n$ is carried out with a chiral quark model. The observations are reasonably described from the $\Delta (1232)$ resonance region up to the $N(1440)$ resonance region. Besides the $\Delta (1232)P_{33}$, a confirmed role of $N(1440)P_{11}$ is found in the polarizations of the ${\pi }^{-}p\to {\pi }^{-}p$ and ${\pi }^{-}p\to {\pi }^{0}n$ reactions. It is found that the $N(1440)N\pi$ and $\Delta (1232)N\pi$ couplings are about $1.7$ and $4.8$ times larger than the expectations from the simple quark model, respectively, which may suggest the unusual property of $N(1440)P_{11}$ and deficiency of the simple quark model in the description of $N(1440)P_{11}$ and $\Delta (1232)P_{33}$. The $t$- and $u$-channel backgrounds have notable contributions to the ${\pi }^{+}p\to {\pi }^{+}p$ reaction, while in the ${\pi }^{-}p\to {\pi }^{-}p,{\pi }^{0}n$ reactions, the $s$-channel nucleon and $t$- and $u$-channel backgrounds play crucial roles.

    ↳ nucl-thhep-phnucl-exPRC(2017)·5 citations
21. 21*

    Type-III and IV interacting Weyl points

    J. Nissinen🇫🇮 · G.E. Volovik🇫🇮

    3+1-dimensional Weyl fermions in interacting systems are described by effective quasi-relativistic Green's functions parametrized by a 16 element matrix $e_{\alpha }^{\mu }$ in an expansion around the Weyl point. The matrix $e_{\alpha }^{\mu }$ can be naturally identified as an effective tetrad field for the fermions. The correspondence between the tetrad field and an effective quasi-relativistic metric $g_{\mu \nu }$ governing the Weyl fermions allows for the possibility to simulate different classes of metric fields emerging in general relativity in interacting Weyl semimetals. According to this correspondence, there can be four types of Weyl fermions, depending on the signs of the components $g^{00}$ and $g_{00}$ of the effective metric. In addition to the conventional type-I fermions with a tilted Weyl cone and type-II fermions with an overtilted Weyl cone for $g^{00}>0$ and respectively $g_{00}>0$ or $g_{00}<0$, we find additional "type-III" and "type-IV" Weyl fermions with instabilities (complex frequencies) for $g^{00}<0$ and $g_{00}>0$ or $g_{00}<0$, respectively. While the type-I and type-II Weyl points allow us to simulate the black hole event horizon at an interface where $g^{00}$ changes sign, the type-III Weyl point leads to effective spacetimes with closed timelike curves.

    ↳ cond-mat.str-elgr-qchep-phJETP Lett.(2017)·50 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.