Fri·Apr 8, 2016Friday·April 8, 2016

1. 01*

   The 750 GeV Resonance as Non-Minimally Coupled Inflaton: Unitarity Violation and Why the Resonance is a Real Singlet Scalar

   J. McDonald🇬🇧

   The 750 GeV resonance observed by ATLAS and CMS may be explained by a gauge singlet scalar. This would provide an ideal candidate for a gauge singlet scalar alternative to Higgs Inflation, S-inflation. Here we discuss the relevant results of S-inflation in the context of the 750 GeV resonance. In particular, we show that a singlet scalar, if it is real, has a major advantage over the Higgs boson with regard to unitarity violation during inflation. This is because it is possible to restrict the large non-minimal coupling required for inflation, $\xi \sim 10^5$, to the real singlet scalar, with all other scalars having $\xi \sim 1$. In this case the scale of unitarity violation $\Lambda$ is much larger than the inflaton field during inflation. This protects the inflaton effective potential from modification by the new physics or strong coupling which is necessary to restore unitarity, which would otherwise invalidate the perturbative effective potential based on Standard Model physics. This is in contrast to the case of Higgs Inflation or models based on complex singlet scalars, where the unitarity violation scale during inflation is less than or of the order of the inflaton field. Therefore if the 750 GeV resonance is the inflaton, it must be a non-minimally coupled real singlet scalar.

   hep-phastro-ph.COhep-thPLB(2016)·9 citations
2. 02*

   B_c^+- decays into tetraquarks

   A. Ali🇩🇪 · L. Maiani🇮🇹 · A.D. Polosa🇮🇹 · V. Riquer🇮🇹

   The recent observation by the D0 collaboration of a narrow structure X(5568) consisting of four different quark flavors bdus, has not been confirmed by LHCb. More data and dedicated analyses are needed to cover a larger mass range. In the tightly bound diquark model, we estimate the lightest bdus, 0^+ tetraquark at a mass of about 5770 MeV, approximately 200 MeV above the reported X(5568), and just 7 MeV below the B Kbar threshold. The charged tetraquark is accompanied by I=1 and I=0 neutral partners almost degenerate in mass. A bdus, S-wave, 1^+ quartet at 5820 MeV is implied as well. In the charm sector, cdus, 0^+ and 1^+ tetraquarks are predicted at 2365 MeV and 2501 MeV, about 40-50 MeV heavier than D_{s0}(2317) and D_{s1}(2460). bdus tetraquarks can be searched in the hadronic debris of a jet initiated by a b. However, some of them may also be produced in B_c decays. The proposed discovery modes of S-wave tetraquarks are B_c --> X_{b0} + pi with the subsequent decays X_{b0} --> B_s + pi, giving rise to final states such as B_s pi^+ pi^0. We also emphasize the importance of B_c decays as a source of bound hidden charm tetraquarks, such as B_c --> X(3872) + pi.

   hep-phPRD(2016)·34 citations
3. 03*

   Large-$N$ Pion Scattering, Finite-Temperature Effects and the Relationship of the $f_0(500)$ with Chiral Symmetry Restoration

   Santiago Cortes🇨🇱 · Angel Gomez Nicola🇪🇸 · John Morales🇨🇴

   In this work, we review how the mass and the width of the $f_0(500)$ pole behave in a regime where temperature is below the critical chiral transition value. This is attained by considering a large-$N$ $O(N+1)/O(N)$ invariant Non-Linear Sigma Model (NLSM) such that we can study the dynamical generation of a $f_0(500)$ resonance. Introducing thermal effects via the imaginary time formalism allows us to study the behavior of the pole and relate it to chiral restoration.

   hep-phActa Phys.Polon.Supp.(2016)·0 citations
4. 04*

   Majorana Dark matter with B+L gauge symmetry

   Wei Chao🇺🇸 · Huai-ke Guo🇺🇸 · Yongchao Zhang🇧🇪

   We present a new model that extends the Standard Model (SM) with the local B+L symmetry, and point out that the lightest new fermion $\zeta$, introduced to cancel anomalies and stabilized automatically by the B+L symmetry, can serve as the cold dark matter candidate. We study constraints on the model from Higgs measurements, electroweak precision measurements as well as the relic density and direct detections of the dark matter. Numerical results reveal that the pseudo-vector coupling of $\zeta$ with $Z$ and the Yukawa coupling with the SM Higgs are highly constrained by the latest results of LUX, while there are viable parameter space that could satisfy all the constraints and give testable predictions.

   hep-phJHEP(2017)·24 citations
5. 05*

   Effects of Bound States on Dark Matter Annihilation

   Haipeng An🇺🇸 · Mark B. Wise🇺🇸 · Yue Zhang🇺🇸

   We study the impact of bound state formation on dark matter annihilation rates in models where dark matter interacts via a light mediator, the dark photon. We derive the general cross section for radiative capture into all possible bound states, and point out its non-trivial dependence on the dark matter velocity and the dark photon mass. For indirect detection, our result shows that dark matter annihilation inside bound states can play an important role in enhancing signal rates over the rate for direct dark matter annihilation with Sommerfeld enhancement. The effects are strongest for large dark gauge coupling and when the dark photon mass is smaller than the typical momentum of dark matter in the galaxy. As an example, we show that for thermal dark matter the Fermi gamma ray constraint is substantially increased once bound state effects are taken into account. We also find that bound state effects are not important for dark matter annihilation during the freeze out and recombination epochs.

   hep-phastro-ph.HEPRD(2016)·88 citations
6. 06*

   Comment on "More on Heisenberg's model for high energy nucleon-nucleon scattering"

   Martin M. Block🇺🇸 · Loyal Durand🇺🇸 · Phuoc Ha🇺🇸 · Francis Halzen🇺🇸

   We comment on the treatment of asymptotic black-disk scattering in a recent paper of Nastase and Sonnenschein, Phys.\ Rev.\ D\ {\bf 92}, 015028 (2015), on scattering in an updated version of the Heisenberg model which gives $pp$ and $\bar{p}p$ cross sections which increase at very high energies as ${\ln }^{2}s$. We show that the total cross section they define does not correspond to that measured in experiments, with the result that their limit for the ratio ${\sigma }_{\mathrm{elas}}/{\sigma }_{\mathrm{tot}}$ is too small by a factor 2. The correct ratio for black-disk scattering, ${\sigma }_{\mathrm{elas}}/{\sigma }_{\mathrm{tot}}\to 1/2$ for $s\to \infty$, is strongly supported by experiment.

   hep-phPRD(2016)·0 citations
7. 07*

   Nonperturbative evaluation of quantum particle production in parametric resonance enhanced by noise

   Asako Murakami🇯🇵 · Haruhiko Terao🇯🇵

   Numerical studies are reported to support the idea to explain the particle production in late inflationary era based on the parametric resonance with a noise effect. Two nonperturbative renormalization group formulations are used to numerically calculate the time evolution of particle numbers. Firstly, the dynamical renormalization group (DRG) method is applied to sum up the secular contributions. Secondly, we derive an exact evolution equation of the particle number which turned out to be possible surprisingly owing to the presence of the noise effect. Our numerical results show a drastic enhancement of the particle production in agreement with earlier works qualitatively. A comparison is made of numerical results based on two methods. Our work provides nonperturbative and quantitative methods to evaluate the particle production for the inflationary cosmology.

   hep-phastro-ph.COhep-th2 citations
8. 08*

   Gamma-ray triangles: a possible signature of asymmetric dark matter in indirect searches

   Alejandro Ibarra🇩🇪 · Sergio Lopez-Gehler🇩🇪 · Emiliano Molinaro🇩🇰 · Miguel Pato🇸🇪

   We introduce a new type of gamma-ray spectral feature, which we denominate gamma-ray triangle. This spectral feature arises in scenarios where dark matter self-annihilates via a chiral interaction into two Dirac fermions, which subsequently decay in flight into another fermion and a photon. The resulting photon spectrum resembles a sharp triangle and can be readily searched for in the gamma-ray sky. Using data from the Fermi-LAT and H.E.S.S. instruments, we find no evidence for such spectral feature and therefore set strong upper bounds on the corresponding annihilation cross section. A concrete realization of a scenario yielding gamma-ray triangles consists of an asymmetric dark matter model where the dark matter particle carries lepton number. We show explicitly that this class of models can lead to intense gamma-ray spectral features, potentially at the reach of upcoming gamma-ray telescopes, opening a new window to explore asymmetric dark matter through indirect searches.

   hep-phastro-ph.HEhep-exPRD(2016)·22 citations
9. 09*

   Vector-like Sneutrino Dark Matter

   Yi-Lei Tang🇨🇳 · Shou-hua Zhu🇨🇳

   In this paper, we discuss the MSSM extended with one vector-like lepton doublets $L$-$\overline{L}$ and one right-handed neutrino $N$. The neutral vecotor-like sneutrino can be a candidate of dark matter. In order to avoid the interaction with the necleons by exchanging a $Z$-boson, the mass splitting between the real part and the imaginary part of the sneutrino field is needed. Compared with the MSSM sneutrino dark matter, the mass splitting between the vector-like sneutrino field can be more naturally acquired without large A-terms and constraints on the neutralino masses. We have also calculated the relic density and the elastic scattering cross sections with the neucleons in the cases that the dark matter particles coannihilate with or without the MSSM slepton doublets. The elastic scattering cross sections with the neucleons are well below the LUX bounds. In the case that the dark matter coannihilate with all the MSSM slepton doublets, the mass of the dark matter can be as light as 370 GeV.

   hep-phPRD(2016)·3 citations
10. 10*

    Inelastic nuclear screening for different secondaries produced in p+Pb collisions at LHC energy

    G.H. Arakelyan🇦🇲 · C. Merino🇪🇸 · Yu.M. Shabelski🇷🇺 · A.G. Shuvaev🇷🇺

    We calculate the inclusive spectra of secondaries produced in soft (minimum bias) p+Pb collisions in the framework of Quark-Gluon String Model at LHC energy, by taking into account the inelastic screening corrections (percolation effects). The role of these effects is expected to be very large at the very high energies, and they should decrease the spectra more than 2 times in the midrapidity region at sqrt(s)_(NN) = 5 TeV. The experimental data confirm such a picture, which means that the nuclear screening effects are connected with the Pomeron interaction rather than with the interactions of the produced secondary particles in the final state.

    hep-phhep-exPRD(2017)·2 citations
11. 11*

    Common Origin of $3.55$ keV X-ray line and Gauge Coupling Unification with Left-Right Dark Matter

    Debasish Borah🇮🇳 · Arnab Dasgupta🇮🇳 · Sudhanwa Patra🇮🇳

    We present a minimal left-right dark matter framework that can simultaneously explain the recently observed 3.55 keV X-ray line from several galaxy clusters and gauge coupling unification at high energy scale. Adopting a minimal dark matter strategy, we consider both left and right handed triplet fermionic dark matter candidates which are stable by virtue of a remnant ${\mathcal{Z}}_2\simeq (-1{)}^{B-L}$ symmetry arising after the spontaneous symmetry breaking of left-right gauge symmetry to that of the standard model. A scalar bitriplet field is incorporated whose first role is to allow radiative decay of right handed triplet dark matter into the left handed one and a photon with energy 3.55 keV. The other role this bitriplet field at TeV scale plays is to assist in achieving gauge coupling unification at a high energy scale within a non-supersymmetric $SO(10)$ model while keeping the scale of left-right gauge symmetry around the TeV corner. Apart from solving the neutrino mass problem and giving verifiable new contributions to neutrinoless double beta decay and charged lepton flavour violation, the model with TeV scale gauge bosons can also give rise to interesting collider signatures like diboson excess, dilepton plus two jets excess reported recently in the large hadron collider data.

    hep-phastro-ph.COPRD(2017)·12 citations
12. 12*

    Fourier-positivity constraints on QCD dipole models

    Bertrand G. Giraud🇫🇷 · Robi Peschanski🇫🇷

    Fourier-positivity, i.e. the mathematical property that a function has a positive Fourier transform, can be used as a constraint on the parametrization of QCD dipole-target cross-sections or Wilson line correlators in transverse position (r) space. They are Bessel transforms of positive transverse momentum dependent gluon distributions. Using mathematical Fourier-positivity constraints on the limit r -> 0 behavior of the dipole amplitudes, we identify the common origin of the violation of Fourier-positivity for various, however phenomenologically convenient, dipole models. It is due to the behavior r^{2+epsilon}, epsilon>0, softer, even slightly, than color transparency. Fourier-positivity seems thus to conflict with the present dipole formalism when it includes a QCD running coupling constant alpha(r).

    hep-phPLB(2016)·19 citations
13. 13*

    Eta and kaon production in a chiral quark model

    Bojan Golli🇸🇮 · Simon Širca🇸🇮

    We apply a coupled-channel formalism incorporating quasi-bound quark-model states to calculate pion scattering into eta N, K Lambda and K Sigma channels, as well eta p, eta n, K+Lambda, and K0Sigma+ photo-production processes. The meson-baryon and photon-baryon vertices are determined in a SU(3) version of the Cloudy Bag Model. Our model predicts sizable amplitudes in the P11, P13, P33 and S11 partial waves in agreement with the latest MAID isobar model and the recent partial-wave analyses of the Bonn-Gatchina group. We are able to give a quark-model explanation for the apparent resonance at 1685 MeV in the eta n channel.

    hep-phnucl-thEPJA(2016)·13 citations
14. 14*

    Higgs Phenomenology in the Minimal $SU(3{)}_L\times U(1{)}_X$ Model

    Hiroshi Okada🇹🇼 · Nobuchika Okada🇺🇸 · Yuta Orikasa🇰🇷 · Kei Yagyu🇬🇧

    We investigate the phenomenology of a model based on the $SU(3{)}_c\times SU(3{)}_L\times U(1{)}_X$ gauge theory, the so-called 331 model. In particular, we focus on the Higgs sector of the model which is composed of three $SU(3{)}_L$ triplet Higgs fields, and this corresponds to the minimal form to realize phenomenologically acceptable scenario. After the spontaneous symmetry breaking $SU(3{)}_L\times U(1{)}_X\to SU(2{)}_L\times U(1{)}_Y$, our Higgs sector effectively becomes that with two $SU(2{)}_L$ doublet scalar fields, in which the first and the second generation quarks couple to the different Higgs doublet from that couples to the third generation quarks. This structure causes the flavour changing neutral current mediated by Higgs bosons at the tree level. By taking an alignment limit of the mass matrix for the CP-even Higgs bosons, which is naturally realized in the case with the breaking scale of $SU(3{)}_L\times U(1{)}_X$ to be much larger than that of $SU(2{)}_L\times U(1{)}_Y$, we can avoid current constraints from flavour experiments such as the $B^0$-${\bar{B}}^0$ mixing even for the Higgs bosons masses being $\mathcal{O}(100)$ GeV. In this allowed parameter space, we clarify that a characteristic deviation in quark Yukawa couplings of the standard model-like Higgs boson is predicted, which has a different pattern from that seen in two Higgs doublet models with a softly-broken $Z_2$ symmetry. We also find that the flavour violating decay modes of the extra Higgs boson, e.g., $H/A\to tc$ and $H^{\pm }\to ts$ can be dominant, and they yield the important signature to distinguish our model from the two Higgs doublet models.

    hep-phPRD(2016)·43 citations
15. 15*

    Angular distributions in $J/\psi \to p\bar{p}{\pi }^0(\eta )$ decays

    V. F. Dmitriev🇷🇺 · A. I. Milstein🇷🇺 · S. G. Salnikov🇷🇺

    The differential decay rates of the processes $J/\psi \to p\bar{p}{\pi }^0$ and $J/\psi \to p\bar{p}\eta$ close to the $p\bar{p}$ threshold are calculated with the help of the $N\bar{N}$ optical potential. The same calculations are made for the decays of $\psi (2S)$. We use the potential which has been suggested to fit the cross sections of $N\bar{N}$ scattering together with $N\bar{N}$ and six pion production in $e^{+}{e}^{-}$ annihilation close to the $p\bar{p}$ threshold. The $p\bar{p}$ invariant mass spectra is in agreement with the available experimental data. The anisotropy of the angular distributions, which appears due to the tensor forces in the $N\bar{N}$ interaction, is predicted close to the $p\bar{p}$ threshold. This anisotropy is large enough to be investigated experimentally. Such measurements would allow one to check the accuracy of the model of $N\bar{N}$ interaction.

    hep-phnucl-thPLB(2016)·9 citations
16. 16*

    Parameterized Relativistic Dynamical Formalism for Transitions between Three Flavor States

    John R. Fanchi🇺🇸

    Parameterized relativistic dynamics (PRD) is a manifestly covariant quantum theory with invariant evolution parameter. The theory has been applied to neutrino flavor oscillations between two mass states. It is generalized here to transitions between three mass states and applied to electron neutrino oscillations.

    hep-ph0 citations
17. 17*

    Renormalization Group Study of the Minimal Majoronic Dark Radiation and Dark Matter Model

    We-Fu Chang🇹🇼 · John N. Ng🇨🇦

    We study the 1-loop renormalization group equation running in the simplest singlet Majoron model constructed by us earlier to accommodate the dark radiation and dark matter content in the universe. A comprehensive numerical study was performed to explore the whole model parameter space. A smaller effective number of neutrinos $△N_{eff}\sim 0.05$, or a Majoron decoupling temperature higher than the charm quark mass, is preferred. We found that a heavy scalar dark matter, $\rho$, of mass $1.5-4$ TeV is required by the stability of the scalar potential and an operational type-I see-saw mechanism for neutrino masses. A neutral scalar, $S$, of mass in the $10-100$ GeV range and its mixing with the standard model Higgs as large as $0.1$ is also predicted. The dominant decay modes are $S$ into $b\bar{b}$ and/or $\omega \omega$. A sensitive search will come from rare $Z$ decays via the chain $Z\to S+f\bar{f}$, where $f$ is a Standard Model fermion, followed by $S$ into a pair of Majoron and/or b-quarks. The interesting consequences of dark matter bound state due to the sizable $S\rho \rho$-coupling are discussed as well. In particular, shower-like events with an apparent neutrino energy at $M_{\rho }$ could contribute to the observed effective neutrino flux in underground neutrino detectors such as IceCube.

    hep-phJCAP(2016)·12 citations
18. 18*

    Deciphering the CP nature of the 750 GeV resonance

    M. Chala🇩🇪 · C. Grojean🇩🇪 · M. Riembau🇩🇪 · T. Vantalon🇩🇪

    The recently observed excess in diphoton events at around 750\,GeV can be satisfactorily described in terms of a new spin-0 real singlet with effective interactions to the gauge bosons. In this letter we first review the current constraints on this setup. We further explore the production in association with a gauge boson. We show the potential of this channel to unravel current flat directions in the allowed parameter space. We then study the potential of two different asymmetries for disentangling the CP nature of such a singlet in both gluon fusion and vector-boson fusion. For this matter, we perform an estimation of the efficiency for selecting signal and background events in eight different decay modes, namely $4\ell ,2j2\ell ,2j\ell E_T^{\text{miss}},2\gamma 2j,4\ell 2j,2\ell \gamma 2j,4j2\ell$ and $4j\ell E_T^{\text{miss}}$. We emphasize that the very different couplings of this new singlet to the Standard Model particles as well as the larger mass provide a distinctive phenomenology with respect to Higgs searches. We finally show that a large region of the parameter space region could be tested within the current LHC run, the dominant channel being $2\gamma 2j$.

    hep-phPLB(2016)·16 citations
19. 19*

    Can the diphoton enhancement at 750 GeV be due to a neutral technipion?

    Piotr Lebiedowicz🇵🇱 · Marta Luszczak🇵🇱 · Roman Pasechnik🇸🇪 · Antoni Szczurek🇵🇱

    We discuss a scenario in which the diphoton enhancement at $M_{\gamma \gamma }$ = 750 GeV, observed by the ATLAS and CMS Collaborations, is a neutral technipion ${\tilde{\pi }}^0$. We consider two distinct minimal models for the dynamical electroweak symmetry breaking. In a first one, two-flavor vector-like technicolor (VTC) model, we assume that the two-photon fusion is a dominant production mechanism. We include $\gamma \gamma \to {\tilde{\pi }}^0$ and production of technipion associated with one or two jets. All the considered mechanisms give similar contributions. With the strong Yukawa (technipion-techniquark) coupling $g_{TC}$ = 10 - 20 we obtain the measured cross section of the "signal". With such values of $g_{TC}$ we get a relatively small ${\Gamma }_{\mathrm{tot}}$. In a second approach, one-family walking technicolor (WTC) model, the isoscalar technipion is produced dominantly via the gluon-gluon fusion. We also discuss the size of the signal at lower energies (LHC, Tevatron) for $\gamma \gamma$ (VTC) and jet-jet (WTC) final states and check consistency with the existing experimental data. We predict a measurable cross section for ${\tilde{\pi }}^0$ production associated with one or two soft jets. The technipion signal in both models is compared with the SM background diphoton contributions. We observe the dominance of inelastic-inelastic processes for $\gamma \gamma$ induced processes. In the VTC scenario, we predict the signal cross section for purely exclusive $pp\to pp\gamma \gamma$ processes at $\sqrt{s}$ = 13 TeV to be about 0.2 fb. Such a cross section would be, however, difficult to measure with the planned integrated luminosity. In all considered cases the signal is below the background or/and below the threshold set by statistics.

    hep-phhep-exPRD(2016)·21 citations
20. 20*

    Synergy between measurements of the gravitational wave and the triple Higgs coupling in probing first order phase transition

    Katsuya Hashino🇯🇵 · Mitsuru Kakizaki🇯🇵 · Shinya Kanemura🇯🇵 · Toshinori Matsui🇯🇵

    Probing the Higgs potential and new physics behind the electroweak symmetry breaking is one of the most important issues of particle physics. In particular, nature of electroweak phase transition is essential for understanding physics at the early Universe, such that the strongly first order phase transition is required for a successful scenario of electroweak baryogenesis. The strongly first order phase transition is expected to be tested by precisely measuring the triple Higgs boson coupling at future colliders like the International Linear Collider. It can also be explored via the spectrum of stochastic gravitational waves to be measured at future space-based interferometers such as eLISA and DECIGO. We discuss complementarity of both the methods in testing the strongly first order phase transition of the electroweak symmetry in models with additional isospin singlet scalar fields with and without classical scale invariance. We find that they are synergetic in identifying specific models of electroweak symmetry breaking in more details.

    hep-phPRD(2016)·114 citations
21. 21*

    Workshop on Physics with Neutral Kaon Beam at JLab (KL2016) Mini-Proceedings

    M. Albrow · M. Amaryan · E. Chudakov · P. Degtyarenko · A. Feijoo · C. Fernandez-Ramirez · I.P. Fernando · A. Filippi · J.L. Goity · H. Haberzettl · B.C. Jackson · H. Kamano and 25 other authors

    The KL2016 Workshop is following the Letter of Intent LoI12-15-001 "Physics Opportunities with Secondary KL beam at JLab" submitted to PAC43 with the main focus on the physics of excited hyperons produced by the Kaon beam on unpolarized and polarized targets with GlueX setup in Hall D. Such studies will broaden a physics program of hadron spectroscopy extending it to the strange sector. The Workshop was organized to get a feedback from the community to strengthen physics motivation of the LoI and prepare a full proposal. Further details about the Workshop can be found on the web page of the conference: http://www.jlab.org/conferences/kl2016/index.html .

    hep-phhep-exnucl-exnucl-th21 citations
22. 22*

    Harmonic expansion of the effective potential in Functional Renormalization Group at finite chemical potential

    G.G. Barnafoldi🇭🇺 · A. Jakovac🇭🇺 · P. Posfay🇭🇺

    In this paper we propose a method to study the Functional Renormalization Group at finite chemical potential. The method consists of mapping the FRG equations within the Fermi surface into a differential equation defined on a rectangle with zero boundary conditions. To solve this equation we use an expansion of the potential in a harmonic basis. With this method we determined the phase diagram of a simple Yukawa-type model; as expected, the bosonic fluctuations decrease the strength of the transition.

    ↳ hep-thhep-phPRD(2017)·10 citations
23. 23*

    The Trispectrum in the Effective Field Theory of Large Scale Structure

    Daniele Bertolini🇺🇸 · Katelin Schutz🇺🇸 · Mikhail P. Solon🇺🇸 · Kathryn M. Zurek🇺🇸

    We compute the connected four point correlation function (the trispectrum in Fourier space) of cosmological density perturbations at one-loop order in Standard Perturbation Theory (SPT) and the Effective Field Theory of Large Scale Structure (EFT of LSS). This paper is a companion to our earlier work on the non-Gaussian covariance of the matter power spectrum, which corresponds to a particular wavenumber configuration of the trispectrum. In the present calculation, we highlight and clarify some of the subtle aspects of the EFT framework that arise at third order in perturbation theory for general wavenumber configurations of the trispectrum. We consistently incorporate vorticity and non-locality in time into the EFT counterterms and lay out a complete basis of building blocks for the stress tensor. We show predictions for the one-loop SPT trispectrum and the EFT contributions, focusing on configurations which have particular relevance for using LSS to constrain primordial non-Gaussianity.

    ↳ astro-ph.COhep-phhep-thJCAP(2016)·93 citations
24. 24*

    Cutkosky Rules for Superstring Field Theory

    Roji Pius🇨🇦 · Ashoke Sen🇮🇳

    Superstring field theory expresses the perturbative S-matrix of superstring theory as a sum of Feynman diagrams each of which is manifestly free from ultraviolet divergences. The interaction vertices fall off exponentially for large space-like external momenta making the ultraviolet finiteness property manifest, but blow up exponentially for large time-like external momenta making it impossible to take the integration contours for loop energies to lie along the real axis. This forces us to carry out the integrals over the loop energies by choosing appropriate contours in the complex plane whose ends go to infinity along the imaginary axis but which take complicated form in the interior navigating around the various poles of the propagators. We consider the general class of quantum field theories with this property and prove Cutkosky rules for the amplitudes to all orders in perturbation theory. Besides having applications to string field theory, these results also give an alternative derivation of Cutkosky rules in ordinary quantum field theories.

    ↳ hep-thgr-qchep-phJHEP(2016)·119 citations
25. 25*

    Search for solar axions with CsI(Tl) crystal detectors

    KIMS Collaboration: Y.S. Yoon · H.K. Park · H. Bhang · J.H. Choi · S. Choi · I.S. Hahn · E.J. Jeon · H.W. Joo · W.G. Kang · B.H. Kim · G.B. Kim · H.J. Kim and 14 other authors

    The results of a search for solar axions from the Korea Invisible Mass Search (KIMS) experiment at the Yangyang Underground Laboratory are presented. Low-energy electron-recoil events would be produced by conversion of solar axions into electrons via the axio-electric effect in CsI(Tl) crystals. Using data from an exposure of 34,596 $\mathrm{kg}\cdot \mathrm{days}$, we set a 90 \% confidence level upper limit on the axion-electron coupling, $g_{ae}$, of $1.39\times 10^{-11}$ for an axion mass less than 1 keV/${\mathrm{c}}^2$. This limit is lower than the indirect solar neutrino bound, and fully excludes QCD axions heavier than 0.48 eV/${\mathrm{c}}^2$ and 140.9 eV/${\mathrm{c}}^2$ for the DFSZ and KSVZ models respectively.

    ↳ hep-exastro-ph.SRhep-phJHEP(2016)·22 citations
26. 26*

    Couplings between the $\rho$ and $D$- and $D^{\ast }$-mesons

    Bruno El-Bennich🇧🇷 · M. Ali Paracha🇵🇰 · Craig D. Roberts🇺🇸 · Eduardo Rojas🇨🇴

    We compute couplings between the $\rho$-meson and $D$- and $D^{\ast }$-mesons - $D^{(\ast )}\rho D^{(\ast )}$ - that are relevant to phenomenological meson-exchange models used to analyse nucleon-$D$-meson scattering and explore the possibility of exotic charmed nuclei. Our framework is built from elements constrained by Dyson-Schwinger equation studies in QCD, and therefore expresses a consistent, simultaneous description of light- and heavy-quarks and the states they constitute, We find that all interactions, including the three independent $D^{\ast }\rho D^{\ast }$ couplings, differ markedly amongst themselves in strength and also in range, as measured by their evolution with $\rho$-meson virtuality. As a consequence, it appears that no single coupling strength or parametrization can realistically be employed in the study of interactions between $D^{(\ast )}$-mesons and matter.

    ↳ nucl-thhep-exhep-lathep-ph+1PRD(2017)·21 citations
27. 27*

    Quantum-gravity effects on a Higgs-Yukawa model

    Astrid Eichhorn🇬🇧 · Aaron Held🇩🇪 · Jan M. Pawlowski🇩🇪

    A phenomenologically viable theory of quantum gravity must accommodate all observed matter degrees of freedom and their properties. Here, we explore whether a toy model of the Higgs-Yukawa sector of the Standard Model is compatible with asymptotically safe quantum gravity. We discuss the phenomenological implications of our result in the context of the Standard Model. We analyze the quantum scaling dimension of the system, and find an irrelevant Yukawa coupling at a joint gravity-matter fixed point. Further, we explore the impact of gravity-induced couplings between scalars and fermions, which are non-vanishing in asymptotically safe gravity.

    ↳ hep-thgr-qchep-phPRD(2016)·155 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.