HEP Phenomenology·hep-ph

Thu·Sep 3, 2015Thursday·September 3, 2015

25 papers—19 primary·6 cross-listed·reconstructed*

01*
NMSGUT emergence and Trans-Unification RG flows
Charanjit S. Aulakh🇮🇳 · Ila Garg🇮🇳 · Charanjit K. Khosa🇮🇳
Consistency of trans-unification RG evolution is used to discuss the domain of definition of the New Minimal Supersymmetric SO(10) GUT (NMSGUT). We compute the 1-loop RGE $β$ functions, simplifying generic formulae using constraints of gauge invariance and superpotential structure. We also calculate the 2 loop contributions to the gauge coupling and gaugino mass and indicate how to get full 2 loop results for all couplings. Our method overcomes combinatorial barriers that frustrate computer algebra based attempts to calculate SO(10) $β$ functions involving large irreps. Use of the RGEs identifies a perturbative domain $Q < M_{E}$ , where $M_{E} < M_{P l an c k}$ is the \emph{scale of emergence} where the NMSGUT, with GUT compatible soft supersymmetry breaking terms emerges from the strong UV dynamics associated with the Landau poles in gauge and Yukawa couplings. Due to the strength of the RG flows the Landau poles for gauge and Yukawa couplings lie near a cutoff scale $Λ_{E}$ for the perturbative dynamics of the NMSGUT which just above $M_{E}$ . SO(10) RG flows into the IR are shown to facilitate small gaugino masses and generation of negative Non Universal Higgs masses squared needed by realistic NMSGUT fits of low energy data. Running the simple canonical theory emergent at $M_{E}$ through $M_{X}$ down to the electroweak scale enables tests of candidate scenarios such as supergravity based NMSGUT with canonical kinetic terms and NMSGUT based dynamical Yukawa unification.
hep-phPRD(2018)·3 citations
02*
LHC dijet constraints on double beta decay
J. C. Helo🇨🇱 · M. Hirsch🇪🇸
We use LHC dijet data to derive constraints on neutrinoless double beta decay. Upper limits on cross sections for the production of "exotic" resonances, such as a right-handed W boson or a diquark, can be converted into lower limits on the double beta decay half-life for fixed choices of other parameters. Constraints derived from run-I data are already surprisingly strong and complementary to results from searches using same-sign dileptons plus jets. For the case of the left-right symmetric model, in case no new resonance is found in future runs of the LHC and assuming $g_{L} = g_{R}$ , we estimate a lower limit on the double beta decay half-live larger than $1 0^{27}$ ys can be derived from future dijet data, except in the window of relatively light right-handed neutrino masses in the range $0.5$ MeV to $50$ GeV. Part of this mass window will be tested in the upcoming SHiP experiment. We also discuss current and future limits on possible scalar diquark contributions to double beta decay that can be derived from dijet data.
hep-phPRD(2015)·21 citations
03*
SOSpin, a C++ library for Yukawa decomposition in SO(2N) models
Nuno Cardoso🇺🇸 · David Emmanuel-Costa🇵🇹 · Nuno Gonçalves🇵🇹 · C. Simoes🇧🇪
We present in this paper the SOSpin library, which calculates an analytic decomposition of the Yukawa interactions invariant under any SO(2N) group in terms of an SU(N) basis. We make use of the oscillator expansion formalism, where the SO(2N) spinor representations are expressed in terms of creation and annihilation operators of a Grassmann algebra. These noncommutative operators and their products are simulated in SOSpin through the implementation of doubly-linked-list data structures. These data structures were determinant to achieve a higher performance in the simplification of large products of creation and annihilation operators. We illustrate the use of our library with complete examples of how to decompose Yukawa terms invariant under SO(2N) in terms of SU(N) degrees of freedom for N=2 and 5. We further demonstrate, with an example for SO(4), that higher dimensional field-operator terms can also be processed with our library. Finally, we describe the functions available in SOSpin that are made to simplify the writing of spinors and their interactions specifically for SO(10) models.
hep-phhep-thphysics.comp-phComput.Phys.Commun.(2016)·4 citations
04*
Describing 2-TeV scale W_L W_L resonances with Unitarized Effective Theory
Felipe J. Llanes-Estrada🇪🇸 · Antonio Dobado🇪🇸 · Rafael L. Delgado (Univ. Complutense Madrid)🇪🇸
The LHC is now exploring the 1-3 TeV scale where resonances of the Electroweak Symmetry Breaking Sector might exist. If so, Unitarized Effective Theory can be used to describe the data with all the constraints of unitarity, causality and global-symmetry breaking, and to find the resonance positions in the complex s-plane. From any resonances found, one can infer the parameters of the universal Effective Lagrangian, and those may be used to inform higher-energy theories (UV completions) that can be matched to it. We exemplify with two-body resonances in the coupled channels hh and W_L W_L- Z_L Z_L employing the Equivalence Theorem and comment on the apparent excess in the ATLAS dijet data at 2 TeV.
hep-phBled Workshops Phys.(2015)·5 citations
05*
Color confinement from fluctuating topology
Dmitri E. Kharzeev🇺🇸
QCD possesses a compact gauge group, and this implies a non-trivial topological structure of the vacuum. In this contribution to the Gribov-85 Memorial volume, we first discuss the origin of Gribov copies and their interpretation in terms of fluctuating topology in the QCD vacuum. We then describe the recent work with E. Levin that links the confinement of gluons and color screening to the fluctuating topology, and discuss implications for spin physics, high energy scattering, and the physics of quark-gluon plasma.
hep-phhep-thnucl-thInt.J.Mod.Phys.A(2016)·6 citations
06*
A Tale of Two Timescales: Mixing, Mass Generation, and Phase Transitions in the Early Universe
Keith R. Dienes🇺🇸 · Jeff Kost🇺🇸 · Brooks Thomas🇺🇸
Light scalar fields such as axions and string moduli can play an important role in early-universe cosmology. However, many factors can significantly impact their late-time cosmological abundances. For example, in cases where the potentials for these fields are generated dynamically --- such as during cosmological mass-generating phase transitions --- the duration of the time interval required for these potentials to fully develop can have significant repercussions. Likewise, in scenarios with multiple scalars, mixing amongst the fields can also give rise to an effective timescale that modifies the resulting late-time abundances. Previous studies have focused on the effects of either the first or the second timescale in isolation. In this paper, by contrast, we examine the new features that arise from the interplay between these two timescales when both mixing and time-dependent phase transitions are introduced together. First, we find that the effects of these timescales can conspire to alter not only the total late-time abundance of the system --- often by many orders of magnitude --- but also its distribution across the different fields. Second, we find that these effects can produce large parametric resonances which render the energy densities of the fields highly sensitive to the degree of mixing as well as the duration of the time interval over which the phase transition unfolds. Finally, we find that these effects can even give rise to a "re-overdamping" phenomenon which causes the total energy density of the system to behave in novel ways that differ from those exhibited by pure dark matter or vacuum energy. All of these features therefore give rise to new possibilities for early-universe phenomenology and cosmological evolution. They also highlight the importance of taking into account the time dependence associated with phase transitions in cosmological settings.
hep-phastro-ph.COhep-thPRD(2016)·27 citations
07*
Anatomy of the Higgs fits: a first guide to statistical treatments of the theoretical uncertainties
Sylvain Fichet🇧🇷 · Grégory Moreau🇫🇷
The studies of the Higgs boson couplings based on the recent and upcoming LHC data open up a new window on physics beyond the Standard Model. In this paper, we propose a statistical guide to the consistent treatment of the theoretical uncertainties entering the Higgs rate fits. Both the Bayesian and frequentist approaches are systematically analysed in a unified formalism. We present analytical expressions for the marginal likelihoods, useful to implement simultaneously the experimental and theoretical uncertainties. We review the various origins of the theoretical errors (QCD, EFT, PDF, production mode contamination...). All these individual uncertainties are thoroughly combined with the help of moment-based considerations. The theoretical correlations among Higgs detection channels appear to affect the location and size of the best-fit regions in the space of Higgs couplings. We discuss the recurrent question of the shape of the prior distributions for the individual theoretical errors and find that a nearly Gaussian prior arises from the error combinations. We also develop the bias approach, which is an alternative to marginalisation providing more conservative results. The statistical framework to apply the bias principle is introduced and two realisations of the bias are proposed. Finally, depending on the statistical treatment, the Standard Model prediction for the Higgs signal strengths is found to lie within either the $68%$ or $95%$ confidence level region obtained from the latest analyses of the $7$ and $8$ TeV LHC datasets.
hep-phNPB(2016)·38 citations
08*
Simplified Models for Exotic BSM Searches
Jan Heisig🇩🇪 · Andre Lessa🇧🇷 · Loic Quertenmont🇧🇪
Simplified models are a successful way of interpreting current LHC searches for models beyond the standard model (BSM). So far simplified models have focused on topologies featuring a missing transverse energy (MET) signature. However, in some BSM theories other, more exotic, signatures occur. If a charged particle becomes long-lived on collider time scales - as it is the case in parts of the SUSY parameter space - it leads to a very distinct signature. We present an extension of the computer package SModelS which includes simplified models for heavy stable charged particles (HSCP). As a physical application we investigate the CMSSM stau co-annihilation strip containing long-lived staus, which presents a potential solution to the Lithium problem. Applying both MET and HSCP constraints we show that, for low values of $tan β$ , all this region of parameter space either violates Dark Matter constraints or is excluded by LHC searches.
hep-phJHEP(2015)·31 citations
09*
Probing MeV to 90 GeV axion-like particles with LEP and LHC
Joerg Jaeckel🇩🇪 · Michael Spannowsky🇬🇧
Axion-like particles (ALPs), relatively light (pseudo-)scalars coupled to two gauge bosons, are a common feature of many extensions of the Standard Model. Up to now there has been a gap in the sensitivity to such particles in the MeV to 10 GeV range. In this note we show that LEP data on $Z \to γ γ$ decays provides significant constraints in this range (and indeed up to the $Z$ -mass). We also discuss the sensitivities of LHC and future colliders. Particularly the LHC shows promising sensitivity in searching for a pseudo-scalar with $4 ≲ m_{a} ≲ 60$ GeV in the channel $pp \to 3 γ$ with $m_{3 γ} \approx m_{Z}$ .
hep-phhep-exPLB(2016)·380 citations
10*
Non-thermal cosmic neutrino background
Mu-Chun Chen🇺🇸 · Michael Ratz🇩🇪 · Andreas Trautner🇩🇪
We point out that, for Dirac neutrinos, in addition to the standard thermal cosmic neutrino background (C $ν$ B) there could also exist a non-thermal neutrino background with comparable number density. As the right-handed components are essentially decoupled from the thermal bath of standard model particles, relic neutrinos with a non-thermal distribution may exist until today. The relic density of the non-thermal (nt) background can be constrained by the usual observational bounds on the effective number of massless degrees of freedom $N_{eff}$ , and can be as large as $n_{ν_{nt}} ≲ 0.5 n_{γ}$ . In particular, $N_{eff}$ can be larger than 3.046 in the absence of any exotic states. Non-thermal relic neutrinos constitute an irreducible contribution to the detection of the C $ν$ B, and, hence, may be discovered by future experiments such as PTOLEMY. We also present a scenario of chaotic inflation in which a non-thermal background can naturally be generated by inflationary preheating. The non-thermal relic neutrinos, thus, may constitute a novel window into the very early universe.
hep-phastro-ph.COPRD(2015)·39 citations
11*
Exploring top quark FCNC within 2HDM type III in association with flavor physics
C. S. Kim🇰🇷 · Yeo Woong Yoon🇰🇷 · Xing-Bo Yuan🇰🇷
The top quark flavor changing neutral current (FCNC) process is an excellent probe to search for new physics in top sector since the Standard Model expectation is extremely suppressed. We explore Higgs-mediated top quark FCNC, focusing on $H$ - $t$ - $c$ Yukawa coupling $λ_{c t}$ within the general two Higgs doublet model. After electroweak symmetry breaking the top quark FCNC couplings are included in the charged Higgs Yukawa sector so that they contribute to various processes in flavor physics. To probe $λ_{c t}$ , we study anomalous single top production and the same sign top pair production at the LHC in association with flavor physics from the tree-level processes $B \to D^{(*)} τ ν$ , $B \to τ ν$ as well as from the loop-level processes $B_{d} \to X_{s} γ$ , $B_{d, s} - B_{d, s}$ mixing. We perform combined analysis of all the constraints regarding the fine-tuning argument to fit the data and discuss future prospect. The recently updated measurements on $B \to D^{(*)} τ ν$ still prefer large $λ_{c t}$ , but we show that the current bound on the same sign top pair production at the LHC gives the most significant upper bound on $λ_{c t}$ to be less than $10 \sim 30$ depending on neutral heavy Higgs masses. We also find that for the given upper bound on $λ_{c t}$ , $B \to D^{(*)} τ ν$ put significant lower bound on $H$ - $τ$ - $τ$ Yukawa coupling, and the bound is proportional to the charged Higgs mass.
hep-phJHEP(2015)·51 citations
12*
Exotic Decays of Heavy B quarks
Patrick J. Fox🇺🇸 · David Tucker-Smith🇺🇸
Heavy vector-like quarks of charge $- 1/3$ , $B$ , have been searched for at the LHC through the decays $B \to b Z, bh, t W$ . In models where the $B$ quark also carries charge under a new gauge group, new decay channels may dominate. We focus on the case where the $B$ is charged under a $U (1)^{'}$ and describe simple models where the dominant decay mode is $B \to b Z^{'} \to b (b b ˉ)$ . With the inclusion of dark matter such models can explain the excess of gamma rays from the Galactic center. We develop a search strategy for this decay chain and estimate that with integrated luminosity of 300 fb $^{- 1}$ the LHC will have the potential to discover both the $B$ and the $Z^{'}$ for $B$ quarks with mass below $\sim 1.6$ TeV, for a broad range of $Z^{'}$ masses. A high-luminosity run can extend this reach to $2$ TeV.
hep-phhep-exJHEP(2016)·3 citations
13*
Chiral-odd generalized parton distributions for proton in a light-front quark-diquark model
Dipankar Chakrabarti🇮🇳 · Chandan Mondal🇮🇳
We present a study of the chiral-odd generalized parton distributions for $u$ and $d$ quarks in a proton using the light front wave functions of the scalar quark-diquark model for nucleon constructed from the soft-wall AdS/QCD correspondence. We obtain the GPDs in terms of overlaps of the LFWFs. Numerical results for chiral-odd GPDs in momentum as well as transverse position spaces considering both zero and nonzero skewness( $ζ$ ) are presented. For nonzero skewness, the GPDs are also evaluated in longitudinal position space.
hep-phPRD(2015)·54 citations
14*
Theoretical Prospects for B Physics
Robert Fleischer🇳🇱
The exploration of B-meson decays has reached an unprecedented level of sophistication, with a phase of even much higher precision ahead of us thanks to run 2 of the LHC and the future era of Belle II and the LHCb upgrade. For many processes, the theoretical challenge in the quest to reveal possible footprints of physics beyond the Standard Model will be the control of uncertainties from strong interactions. After a brief discussion of the global picture emerging from the LHC data, I will focus on the theoretical prospects and challenges for benchmark B decays to search for new sources of CP violation, and highlight future opportunities to probe the Standard Model with strongly suppressed rare B decays.
hep-phhep-exPoS(2015)·13 citations
15*
The (magnetized) effective QCD phase diagram
Alejandro Ayala🇲🇽
I present the highlights of a recent study of the effective QCD phase diagram on the temperature T and quark chemical potential mu plane, where the strong interactions are modeled using the linear sigma model coupled to quarks. The phase transition line is found from the effective potential at finite T and mu taking into account the plasma screening effects. We find the location of the critical end point (CEP) to be (mu^CEP/T_c,T^CEP/T_c) \sim (1.2,0.8), where T_c is the (pseudo)critical temperature for the crossover phase transition at vanishing mu. This location lies within the region found by lattice inspired calculations. Since the linear sigma model does not exhibit confinement, I argue that the location is due to the proper treatment of the plasma screening effects and not to the size of the confining scale. I also comment on the extension of this study to determine the dependence of the CEP's location on the strength of an external magnetic field.
hep-phhep-latnucl-th0 citations
16*
Axions and Dark Matter
Qiaoli Yang🇨🇳
Dark matter constitutes about $23%$ of the total energy density of the universe but its properties are still little known besides that it should be composed by cold and weakly interacting particles. Many beyond standard model theories can provide proper candidates to serve as dark matter and the axion introduced to solve the strong CP problem turns out to be an attractive one. In this paper, we briefly review several important features of the axion and the axion dark matter.
hep-phastro-ph.COMod.Phys.Lett.A(2017)·8 citations
17*
Search for missing $ψ (4 S)$ in the $e^{+} e^{-} \to π^{+} π^{-} ψ (2 S)$ process
Dian-Yong Chen🇨🇳 · Xiang Liu🇨🇳 · Takayuki Matsuki🇯🇵
A detailed analysis to find a missing $ψ (4 S)$ is made by utilizing the recent precise mesurements of the cross section for the process $e^{+} e^{-} \to ψ (2 S) π^{+} π^{-}$ by Belle. Assuming three resonances $Y (4360)$ , $Y (4660)$ , and $ψ (4 S)$ to fit the data, we obtain the resonance parameters for $ψ (4 S)$ as $m = 4243$ MeV and $Γ = 16 \pm 31$ MeV showing a narrow state as predicted before. A combined fit to the data $e^{+} e^{-} \to ψ (2 S) π^{+} π^{-}, h_{c} π^{+} π^{-}$ , and $χ_{c 0} ω$ is also performed to obtain the similar resonance parameters of $ψ (4 S)$ . The upper limit of the branching ratio is fitted to be $B (ψ (4 S) \to ψ (2 S) π^{+} π^{-}) < 3 \times 1 0^{- 3}$ , which can be understood by hadronic loop contributions in reasonable parameters range. In addition, the ratios of the branching ratios of the $ψ (4 S)$ dipion transition to the one of $ψ (4 S) \to χ_{c 0} ω$ are fitted, which can be further measured by BESIII and forthcoming BelleII to confirm the existence of $ψ (4 S)$ .
hep-phPRD(2016)·21 citations
18*
nCTEQ15 - Global analysis of nuclear parton distributions with uncertainties in the CTEQ framework
K. Kovarik🇩🇪 · A. Kusina🇫🇷 · T. Jezo🇮🇹 · D. B. Clark🇺🇸 · C. Keppel🇺🇸 · F. Lyonnet🇺🇸 · J. G. Morfin🇺🇸 · F. I. Olness🇺🇸 · J. F. Owens🇺🇸 · I. Schienbein🇫🇷 · J. Y. Yu🇺🇸
We present the new nCTEQ15 set of nuclear parton distribution functions with uncertainties. This fit extends the CTEQ proton PDFs to include the nuclear dependence using data on nuclei all the way up to 208^Pb. The uncertainties are determined using the Hessian method with an optimal rescaling of the eigenvectors to accurately represent the uncertainties for the chosen tolerance criteria. In addition to the Deep Inelastic Scattering (DIS) and Drell-Yan (DY) processes, we also include inclusive pion production data from RHIC to help constrain the nuclear gluon PDF. Furthermore, we investigate the correlation of the data sets with specific nPDF flavor components, and asses the impact of individual experiments. We also provide comparisons of the nCTEQ15 set with recent fits from other groups.
hep-phPRD(2016)·692 citations
19*
Comment on "A possible explanation of the D0 like-sign dimuon charge aymmetry"
Michael Gronau🇮🇱 · Jonathan L. Rosner🇺🇸
We show that a contribution due to a second order amplitude with intermediate $u ˉ d$ in a loop, which was claimed by Descotes-Genon and Kamenik to dominate the CP asymmetry in $b \to c ℓ ν$ , vanishes.
hep-phhep-exPRD(2015)·0 citations
20*
Current Status of Nuclear Physics Research
C.A. Bertulani (Tamu-Commerce)🇺🇸 · M.S. Hussein (USP)🇧🇷
In this review we discuss the current status of research in nuclear physics which is being carried out in different centers in the World. For this purpose we supply a short account of the development in the area which evolved over the last 9 decades, since the discovery of the neutron. The evolution of the physics of the atomic nucleus went through many stages as more data become available. We briefly discuss models introduced to discern the physics behind the experimental discoveries, such as the shell model, the collective model, the statistical model, the interacting boson model, etc., some of these models may be seemingly in conflict with each other, but this was shown to be only apparent. The richness of the ideas and abundance of theoretical models attests to the important fact that the nucleus is a really singular system in the sense that it evolves from two-body bound states such as the deuteron, to few-body bound states, such as $^{4}$ He, $^{7}$ Li, $^{9}$ Be etc. and up the ladder to heavier bound nuclei containing up to more than 200 nucleons. Clearly statistical mechanics does not work for such finite system, neither does other theories applicable to condensed matter systems. The richness of nuclear physics stems from these restrictions. New theories and models are presently being developed. Theories of the structure and reactions of neutron-rich and proton-rich nuclei, called exotic nuclei, halo nuclei, or Borromean nuclei deal with the wealth of experimental data available in the last 35 years. Further, nuclear astrophysics and stellar and Big Bang nucleosynthesis have become a more mature subject. Due to limited space, this review only covers a few selected topics, mainly those with which the authors have worked with.
↳ nucl-thhep-exhep-phnucl-exBraz.J.Phys.(2015)·8 citations
21*
Magnetic Corrections to the Soft Photon Theorem
Andrew Strominger🇺🇸
The soft photon theorem, in its standard form, requires corrections when the asymptotic particle states carry magnetic charges. These corrections are deduced using electromagnetic duality and the resulting soft formula conjectured to be exact for all abelian gauge theories. Recent work has shown that the standard soft theorem implies an infinity of conserved electric charges. The associated symmetries are identified as `large' electric gauge transformations. Here the magnetic corrections to the soft theorem are shown to imply a second infinity of conserved magnetic charges. The associated symmetries are identified as `large' magnetic gauge transformations. The large magnetic symmetries are naturally subsumed in a complexification of the electric ones.
↳ hep-thgr-qchep-phmath-ph+1PRL(2016)·114 citations
22*
Kaon BSM B-parameters using improved staggered fermions from $N_{f} = 2 + 1$ unquenched QCD
Benjamin J. Choi🇰🇷 · Yong-Chull Jang🇰🇷 · Chulwoo Jung🇺🇸 · Hwancheol Jeong🇰🇷 · Jangho Kim · Jongjeong Kim · Sunghee Kim · Weonjong Lee🇰🇷 · Jaehoon Leem🇰🇷 · Jeonghwan Pak🇰🇷 · Sungwoo Park🇰🇷 · Stephen R. Sharpe🇺🇸 · Boram Yoon (SWME Collaboration)🇺🇸
We present results for the matrix elements of the additional $Δ S = 2$ operators that appear in models of physics beyond the Standard Model (BSM), expressed in terms of four BSM $B$ -parameters. Combined with experimental results for $Δ M_{K}$ and $ϵ_{K}$ , these constrain the parameters of BSM models. We use improved staggered fermions, with valence HYP-smeared quarks and $N_{f} = 2 + 1$ flavors of "asqtad" sea quarks. The configurations have been generated by the MILC collaboration. The matching between lattice and continuum four-fermion operators and bilinears is done perturbatively at one-loop order. We use three lattice spacings for the continuum extrapolation: $a \approx 0.09$ , $0.06$ and $0.045$ fm. Valence light-quark masses range down to $\approx m_{s}^{phys} /13$ while the light sea-quark masses range down to $\approx m_{s}^{phys} /20$ . Compared to our previous published work, we have added four additional lattice ensembles, leading to better controlled extrapolations in the lattice spacing and sea-quark masses. We report final results for two renormalization scales, $μ = 2 GeV$ and $3 GeV$ , and compare them to those obtained by other collaborations. Agreement is found for two of the four BSM $B$ -parameters ( $B_{2}$ and $B_{3}^{SUSY}$ ). The other two ( $B_{4}$ and $B_{5}$ ) differ significantly from those obtained using RI-MOM renormalization as an intermediate scheme, but are in agreement with recent preliminary results obtained by the RBC-UKQCD collaboration using RI-SMOM intermediate schemes.
↳ hep-lathep-phPRD(2016)·83 citations
23*
The effective field theory of K-mouflage
Philippe Brax🇫🇷 · Patrick Valageas🇫🇷
We describe K-mouflage models of modified gravity using the effective field theory of dark energy. We show how the Lagrangian density $K$ defining the K-mouflage models appears in the effective field theory framework, at both the exact fully nonlinear level and at the quadratic order of the effective action. We find that K-mouflage scenarios only generate the operator $(δ g_{(u)}^{00})^{n}$ at each order $n$ . We also reverse engineer K-mouflage models by reconstructing the whole effective field theory, and the full cosmological behaviour, from two functions of the Jordan-frame scale factor in a tomographic manner. This parameterisation is directly related to the implementation of the K-mouflage screening mechanism: screening occurs when $K^{'}$ is large in a dense environment such as the deep matter and radiation eras. In this way, K-mouflage can be easily implemented as a calculable subclass of models described by the effective field theory of dark energy which could be probed by future surveys.
↳ astro-ph.COgr-qchep-phJCAP(2016)·19 citations
24*
Topology, the meson spectrum and the scalar glueball: three probes of conformality and the way it is lost
Elisabetta Pallante🇳🇱
We discuss properties of non-Abelian gauge theories that change significantly across the lower edge of the conformal window. Their probes are the topological observables, the meson spectrum and the scalar glueball operator. The way these quantities change tells about the way conformal symmetry is lost.
↳ hep-thhep-lathep-phInt.J.Mod.Phys.A(2017)·0 citations
25*
QED effects in the pseudoscalar meson sector
R. Horsley🇬🇧 · Y. Nakamura🇯🇵 · H. Perlt🇩🇪 · D. Pleiter🇩🇪 · P. E. L. Rakow🇬🇧 · G. Schierholz🇩🇪 · A. Schiller🇩🇪 · R. Stokes🇦🇺 · H. Stüben🇩🇪 · R. D. Young🇦🇺 · J. M. Zanotti🇦🇺
We present results on the pseudoscalar meson masses from a fully dynamical simulation of QCD+QED. We concentrate particularly on violations of isospin symmetry. We calculate the $π^{+}$ - $π^{0}$ splitting and also look at other isospin violating mass differences. We have presented results for these isospin splittings in arXiv:1508.06401 [hep-lat]. In this paper we give more details of the techniques employed, discussing in particular the question of how much of the symmetry violation is due to QCD, arising from the different masses of the $u$ and $d$ quarks, and how much is due to QED, arising from the different charges of the quarks. This decomposition is not unique, it depends on the renormalisation scheme and scale. We suggest a renormalisation scheme in which Dashen's theorem for neutral mesons holds, so that the electromagnetic self-energies of the neutral mesons are zero, and discuss how the self-energies change when we transform to a scheme such as $M S ˉ$ , in which Dashen's theorem for neutral mesons is violated.
↳ hep-lathep-phnucl-thJHEP(2016)·65 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.