Wed·Oct 28, 2015Wednesday·October 28, 2015

1. 01*

   Constraints on the $\eta {\eta }^{\prime }$ decay rate of a scalar glueball from gauge/gravity duality

   Frederic Brünner🇦🇹 · Anton Rebhan🇦🇹

   Predictions of glueball decay rates in the holographic Witten-Sakai-Sugimoto model for low-energy QCD can be uniquely extended to include finite quark masses up to an as yet undetermined parameter in the coupling of glueballs to the nonanomalous part of the pseudoscalar mass terms. The assumption of a universal coupling of glueballs to mass terms of the full nonet of pseudoscalar mesons leads to flavor asymmetries in the decay rates of scalar glueballs that agree well with experimental data for the glueball candidate $f_0(1710)$ and implies a vanishing decay rate into $\eta {\eta }^{\prime }$ pairs, for which only upper bounds for the $f_0(1710)$ meson are known at present from experiment. Relaxing this assumption, the holographic model gives a tight correlation between the decay rates into pairs of pseudo-Goldstone bosons of same type and $\eta {\eta }^{\prime }$ pairs. If $\Gamma (G\to KK)/\Gamma (G\to \pi \pi )$ is kept within the range reported currently by the Particle Data Group for the $f_0(1710)$ meson, the rate $\Gamma (G\to \eta {\eta }^{\prime })/\Gamma (G\to \pi \pi )$ is predicted to be $\lesssim 0.04$. The corresponding situation for $f_0(1500)$ is also discussed, which however is found to be much less compatible with the interpretation of a largely unmixed glueball.

   hep-phhep-thnucl-thPRD(2015)·38 citations
2. 02*

   Convexity, gauge-dependence and tunneling rates

   Alexis D. Plascencia🇬🇧 · Carlos Tamarit🇬🇧

   We clarify issues of convexity, gauge-dependence and radiative corrections in relation to tunneling rates. Despite the gauge dependence of the effective action at zero and finite temperature, it is shown that tunneling and nucleation rates remain independent of the choice of gauge-fixing. Taking as a starting point the functional that defines the transition amplitude from a false vacuum onto itself, it is shown that decay rates are exactly determined by a non-convex, false vacuum effective action evaluated at an extremum. The latter can be viewed as a generalized bounce configuration, and gauge-independence follows from the appropriate Nielsen identities. This holds for any election of gauge-fixing that leads to an invertible Faddeev-Popov matrix.

   hep-phhep-thJHEP(2016)·69 citations
3. 03*

   Searching SUSY from below

   Giovanni Grilli di Cortona🇮🇹

   We studied the interplay between the mass reach for electroweakinos at future hadron colliders and direct detection experiments. The lack of new phenomena at the LCH motivates us to focus on split supersymmetry scenarios with different electroweakino spectra. A 100 TeV hadron collider may reach masses up to 3 TeV in models of anomaly mediation with long-lived thermal Winos. Moreover, in scenarios where the lightest neutralino is not the only dark matter component, the interplay between collider searches and direct detection experiments might cover large part of the parameter space.

   hep-phPoS(2015)·3 citations
4. 04*

   Lepton Flavor and Non-Universality from Minimal Composite Higgs Setups

   Adrian Carmona🇨🇭 · Florian Goertz🇨🇭

   We present a new class of models of lepton flavor in the composite Higgs framework. Following the concept of minimality, they lead to a rich phenomenology in good agreement with the current experimental picture. Because of a unification of the right-handed leptons, our scenario is very predictive and can naturally lead to a violation of lepton-flavor universality in neutral current interactions. We will show that, in particular, the anomaly in $R_K=\mathcal{B}(B\to K{\mu }^{+}{\mu }^{-})/\mathcal{B}(B\to K{e}^{+}{e}^{-})$, found by LHCb, can be addressed, while other constraints from quark- and lepton-flavor physics are met. In fact, the minimal structure of the setup allows for the implementation of a very powerful flavor protection, which avoids the appearance of new sources of flavor-changing neutral currents to very good approximation. Finally, the new lepton sector provides a parametrically enhanced correction to the Higgs mass, such that the need for ultra-light top partners is weakened considerably, linking the mass of the latter with the size of the neutrino masses.

   hep-phPRL(2016)·91 citations
5. 05*

   Towards model-independent exclusion of light Stops

   Alexander Belyaev🇬🇧 · Veronica Sanz🇬🇧 · Marc Thomas🇬🇧

   Understanding the extent to which experimental searches are sensitive to Light Stops (LST) scenarios is essential to resolve questions about naturalness, electroweak baryogenesis and Dark Matter. In this paper we characterize the reach on LST scenarios in two ways. We extend experimental searches to cover specific gaps in the LST parameter space, showing for the first time that assuming a single decay channel one can exclude the region of $m_{\tilde{t}}<m_{top}$, which in its turn excludes electroweak baryogenesis in MSSM. Also, we explore the extent to which searches are weakened in a more generic scenario when more than one decay channel takes place, even after their combination. This study highlights the need for a more comprehensive exploration of the LST parameter space.

   hep-phJHEP(2016)·10 citations
6. 06*

   ATLAS on-Z Excess via gluino-Higgsino-singlino decay chains in the NMSSM

   Keisuke Harigaya🇯🇵 · Masahiro Ibe🇯🇵 · Teppei Kitahara🇩🇪

   Recently the ATLAS experiment has reported 3.0 sigma excess in an on-Z signal region in searches for supersymmetric particles. We find that the next-to-minimal supersymmetric standard model can explain this excess by the production of gluinos which mainly decay via $\tilde{g}\to g{\tilde{\chi }}_{2,3}^0\to gZ{\tilde{\chi }}_1^0$ where ${\tilde{\chi }}_{2,3}^0$ and ${\tilde{\chi }}_1^0$ are the Higgsino and the singlino-like neutralinos, respectively. We show that the observed dark matter density is explained by the thermal relic density of the singlino-like neutralino, simultaneously. We also discuss the searches for the Higgs sector of this scenario at the Large Hadron Collider.

   hep-phhep-exJHEP(2016)·4 citations
7. 07*

   Probing Higgs self-interactions in proton-proton collisions at a center-of-mass energy of 100 TeV

   Benjamin Fuks🇫🇷 · Jeong Han Kim🇰🇷 · Seung J. Lee🇰🇷

   We present a phenomenological study of triple-Higgs production in which we estimate the prospects for measuring the form of the Higgs potential at future circular collider projects. We analyze proton-proton collisions at a center-of-mass energy of 100 TeV and focus on two different signatures in which the final state is made of four b-jets and either a pair of photons or a pair of tau leptons. We study the resulting sensitivity on the Higgs cubic and quartic self-interactions and investigate how it depends on the b-tagging, tau-tagging and photon resolution performances of detectors that could be designed for these future machines. We then discuss possible luminosity goals for future 100 TeV collider projects that would allow for a measurement of the Higgs potential and its possible departures from the Standard Model expectation.

   hep-phPRD(2016)·51 citations
8. 08*

   The Polyakov, Nambu and Jona-Lasinio model and its applications to describe the sub-nuclear particles

   Eric Blanquier🇫🇷

   To study the high energy nuclear physics and the associated phenomenon, as the QGP/hadronic matter phase transition, the Nambu and Jona-Lasinio model (NJL) appears as an interesting alternative to the Quantum Chromodynamics, which is not solvable at the considered energies. Indeed, the NJL model allows describing the quarks physics, at finite temperatures and finite densities. Furthermore, in order to try to correct a limitation of the NJL model, i.e. the absence of confinement, it was proposed to couple the quarks/antiquarks to a Polyakov loop: it forms the PNJL model. The objective of this thesis is to see the possibilities offered by the NJL and PNJL models, to describe the relevant sub-nuclear particles (quarks, mesons, diquarks and baryons), to study their interactions, and to proceed to a dynamical study involving these particles.

   hep-ph6 citations
9. 09*

   Probing heavy neutrinos in the COMET experiment

   Takehiko Asaka🇯🇵 · Atsushi Watanabe🇯🇵

   We argue that the COMET experiment --- a dedicated experiment for the $\mu$-$e$ conversion search --- can be a powerful facility to search for heavy neutrinos in the mass range $1\mathrm{MeV}\lesssim M\lesssim 100\mathrm{MeV}$. The stopped muons captured by the target nuclei or decaying in orbit are efficiently produce heavy neutrinos via the active-sterile mixing. The produced heavy neutrinos then decay to electron-positron pair (plus an active neutrino), which events are clearly seen by the cylindrical drift chamber surrounding the target. The expected sensitivity is comparable to the PS191 bound when the COMET experiment achieves $\sim 10^{17}$ stopping muons in the target.

   hep-phhep-exPTEP(2016)·1 citation
10. 10*

    Baryon properties from light-front holographic QCD

    Tianbo Liu🇨🇳 · Bo-Qiang Ma🇨🇳

    We investigate the properties of octet and decuplet baryons in a light-front holographic model. By taking into account the effect of nonvanishing quark mass, we obtain the modified light-front wave functions which are applicable at both low and high energy scales. We calculate the spectra, form factors, magnetic moments and electromagnetic radii of octet and decuplet baryons with the results all matching the experiments well. The axial charge, which describes the contribution of quark helicity to the proton spin in the quark-parton model at the high energy scale, is also consistent with the experimental value. Therefore, the light-front holographic method is successful in studying hadronic physics at all energy scales, and the nonzero quark mass is essential to understand the spin structures together with other low energy properties.

    hep-phPRD(2015)·34 citations
11. 11*

    The three-loop cusp anomalous dimension in QCD and its supersymmetric extensions

    Andrey Grozin🇷🇺 · Johannes M. Henn🇩🇪 · Gregory P. Korchemsky🇫🇷 · Peter Marquard🇩🇪

    We present the details of the analytic calculation of the three-loop angle-dependent cusp anomalous dimension in QCD and its supersymmetric extensions, including the maximally supersymmetric $\mathcal{N}=4$ super Yang-Mills theory. The three-loop result in the latter theory is new and confirms a conjecture made in our previous paper. We study various physical limits of the cusp anomalous dimension and discuss its relation to the quark-antiquark potential including the effects of broken conformal symmetry in QCD. We find that the cusp anomalous dimension viewed as a function of the cusp angle and the new effective coupling given by light-like cusp anomalous dimension reveals a remarkable universality property -- it takes the same form in QCD and its supersymmetric extensions, to three loops at least. We exploit this universality property and make use of the known result for the three-loop quark-antiquark potential to predict the special class of nonplanar corrections to the cusp anomalous dimensions at four loops. Finally, we also discuss in detail the computation of all necessary Wilson line integrals up to three loops using the method of leading singularities and differential equations.

    hep-phhep-thJHEP(2016)·159 citations
12. 12*

    Spontaneous Baryogenesis from Asymmetric Inflaton

    Fuminobu Takahashi🇯🇵 · Masaki Yamada🇯🇵

    We propose a variant scenario of spontaneous baryogenesis from asymmetric inflaton based on current-current interactions between the inflaton and matter fields with a non-zero B-L charge. When the inflaton starts to oscillate around the minimum after inflation, it may lead to excitation of a CP-odd component, which induces an effective chemical potential for the B-L number through the current-current interactions. We study concrete inflation models and show that the spontaneous baryogenesis scenario can be naturally implemented in the chaotic inflation in supergravity.

    hep-phastro-ph.COPLB(2016)·23 citations
13. 13*

    Significance of non-perturbative input to TMD gluon density for hard processes at LHC

    A.A. Grinyuk🇷🇺 · A.V. Lipatov🇷🇺 · G.I. Lykasov🇷🇺 · N.P. Zotov🇷🇺

    We study the role of the non-perturbative input to the transverse momentum dependent (TMD) gluon density in hard processes at the LHC. We derive the input TMD gluon distribution at low scale mu0^2 ~ 1 GeV^2 from the fit of the inclusive hadron spectra measured at low transverse momenta in pp collisions at the LHC and demonstrate that the best description of these spectra for larger hadron transverse momenta can be achieved by matching the derived TMD gluon distribution with the exact solution of the Balitsky-Fadin-Kuraev-Lipatov (BFKL) equation obtained at low x and small gluon transverse momenta outside the saturation region. Then, we extend the input TMD gluon density to higher mu^2 numerically using the Catani-Ciafoloni-Fiorani-Marchesini (CCFM) gluon evolution equation. A special attention is put to the phenomenological applications of obtained TMD gluon density to some LHC processes, which are sensitive to the gluon content of a proton.

    hep-phPRD(2016)·11 citations
14. 14*

    SU(2)${}_L\times$SU(2)${}_R$ minimal dark matter with 2 TeV $W^{\prime }$

    P. Ko🇰🇷 · Takaaki Nomura🇰🇷

    We construct the minimal dark matter models in the left-right symmetric extensions of the standard model (SM), where the gauge symmetry SU(3)${}_C\times$SU(2)${}_L\times$SU(2)${}_R\times$U(1)${}_{B-L}$ is broken into its subgroup SU(3)${}_C\times$U(1)${}_{\mathrm{em}}$ by nonzero VEVs of a SU(2)${}_R$ doublet $H_R$ and a SU(2)${}_L\times$ SU(2)${}_R$ bidoublet $H$. A possible candidate of dark matter is explored in the framework of minimal dark matter considering SU(2)${}_{L,R}$ multiplet scalar bosons and fermions. Then we focus on SU(2)${}_R$ quintuplet fermions with $B-L$ charges 0, 2 and 4 as the minimal dark matter candidates and investigate phenomenology of them. We show that the dark matter in the model can provide observed relic density with 2 TeV $W^{\prime }$ boson which is motivated by the ATLAS diboson excess and CMS $eejj$ excess. The possible mass of dark matter is predicted for each $B-L$ charge. We then estimate the scattering cross section of dark matter with nucleon and production cross section of charged components in the quintuplets at the LHC.

    hep-phhep-exPLB(2016)·25 citations
15. 15*

    Heavy neutrinos in particle physics and cosmology

    Marco Drewes🇩🇪

    Neutrinos are the only particles in the Standard Model of particle physics that have only been observed with left handed chirality to date. If right handed neutrinos exist, they would not only explain the observed neutrino oscillations, but could also be responsible for several phenomena in cosmology, including the baryon asymmetry of the universe, dark matter and dark radiation. A crucial parameter in this context is their Majorana mass, which in principle could lie anywhere between the eV scale and GUT scale. The implications for experiments and cosmology strongly depend on the choice of the mass scale. We review recent progress in the phenomenology of right handed neutrinos with different masses, focusing on scenarios in which the mass is at least a keV. We emphasise the possibility to discover heavy neutrinos that are responsible for the baryon asymmetry of the universe via low scale leptogenesis in near future experiments, such as LHC, BELLE II, SHiP, FCC-ee or CEPC.

    hep-phhep-exPoS(2015)·9 citations
16. 16*

    Sigma Decomposition: The CP-Odd Lagrangian

    I.M. Hierro🇮🇹 · L. Merlo🇪🇸 · S. Rigolin🇮🇹

    In Alonso et al., JHEP 12 (2014) 034, the CP-even sector of the effective chiral Lagrangian for a generic composite Higgs model with a symmetric coset has been constructed, up to four momenta. In this paper, the CP-odd couplings are studied within the same context. If only the Standard Model bosonic sources of custodial symmetry breaking are considered, then at most six independent operators form a basis. One of them is the weak-$\theta$ term linked to non-perturbative sources of CP viola- tion, while the others describe CP-odd perturbative couplings between the Standard Model gauge bosons and an Higgs-like scalar belonging to the Goldstone boson sector. The procedure is then applied to three distinct exemplifying frameworks: the original $SU(5)/SO(5)$ Georgi-Kaplan model, the minimal custodial-preserving $SO(5)/SO(4)$ model and the minimal $SU(3)/(SU(2)\times U(1))$ model, which intrinsically breaks cus- todial symmetry. Moreover, the projection of the high-energy electroweak effective theory to the low-energy chiral effective Lagrangian for a dynamical Higgs is per- formed, uncovering strong relations between the operator coefficients and pinpointing the differences with the elementary Higgs scenario.

    hep-phJHEP(2016)·38 citations
17. 17*

    Charmonium Production with QGP and Hadron Gas Effects at SPS and FAIR

    Baoyi Chen

    The production of charmonium in heavy-ion collisions is investigated based on Boltzmann-type transport model for charmonium evolution and langevin equation for charm quark evolution. Charmonium suppression and regeneration in both quark-gluon plasma (QGP) and hadron phase are considered. Charm quarks are far from thermalization, and regeneration of charmonium in QGP and hadron gas is neglectable at SPS and FAIR. At peripheral collisions, charmonium suppression with hadron gas explains the experimental data well. But at central collisions, additional suppression from deconfined matter (QGP) is necessary for the data. This means there should be QGP produced at central collisions, and no QGP produced at peripheral collisions at SPS energy. Predictions are also made at FAIR $\sqrt{s_{NN}}=7.7$ GeV Au+Au collisions.

    hep-phnucl-thPRC(2016)·10 citations
18. 18*

    $L\to l{l}^{\prime }{l}^{\prime }{\nu }_l{\nu }_L$ in the SM and beyond

    A. Flores-Tlalpa🇲🇽 · G. López-Castro🇲🇽 · P. Roig🇲🇽

    We study the $L\to l{l}^{\prime }{l}^{\prime }{\nu }_l{\nu }_L$ decays ($L=\tau ,\mu$; $l,l^{\prime }=\mu ,e$) in the Standard Model (SM) and in the effective field theory (EFT) description of the weak charged current at low energy, both for polarized and unpolarized $L$, keeping the $l,l^{\prime }$ mass dependence. We clarify the discrepancy between two previous SM calculations of the decay rate improving their precision. The recent $3.5\sigma$ anomaly found in $\tau \to e\gamma {\bar{\nu }}_e{\nu }_{\tau }$ could be checked using our precise prediction for the $\tau \to eee{\bar{\nu }}_e{\nu }_{\tau }$ decays, which shall be measured analyzing already existing data from the first generation B-factories. It is shown how measurements of the di-$l^{\prime }$ mass distribution (with appropriate cuts) and $T$-asymmetries are able to reveal the corresponding lepton flavor violating (LFV) processes without neutrinos in the final state.

    hep-phhep-exJ.Univ.Sci.Tech.China(2016)·0 citations
19. 19*

    Hunting for heavy composite Majorana neutrinos at the LHC

    R. Leonardi🇮🇹 · L. Alunni🇮🇹 · F. Romeo🇨🇳 · L. Fanò🇮🇹 · O. Panella🇮🇹

    We investigate the search for heavy Majorana neutrinos stemming from a composite model scenario at the upcoming LHC Run II at a center of mass energy of 13 TeV. While previous studies of the composite Majorana neutrino were focussed on gauge interactions via magnetic type transition coupling between ordinary and heavy fermions (with mass $m^{\ast }$) here we complement the composite model with contact interactions at the energy scale $\Lambda$ and we find that the production cross sections are dominated by such contact interactions by roughly two/three orders of magnitude. This mechanism provides therefore very interesting rates at the prospected luminosities. We study the same sign di-lepton and di-jet signature ($pp\to \ell \ell jj$) and perform a fast detector simulation based on Delphes. We compute 3$\sigma$ and 5$\sigma$ contour plots of the statistical significance in the parameter space ($\Lambda ,m^{\ast }$). We find that the potentially excluded regions at $\sqrt{s}=13$ TeV are quite larger than those excluded so far at Run I considering searches with other signatures.

    hep-phEPJC(2016)·40 citations
20. 20*

    Phenomenology of the Renormalizable Coloron Model

    Arsham Farzinnia🇰🇷

    The renormalizable coloron model constitutes the minimal extension of the standard model (SM) color sector to $SU(3{)}_{1c}\times SU(3{)}_{2c}$, with the spontaneous symmetry breaking of the extended gauge group to the diagonal QCD facilitated by the renormalizable operators. It predicts the existence of the beyond the SM massive color-octet gauge bosons (colorons), colored and uncolored scalar degrees of freedom, as well as potential spectator fermions necessary for anomaly-cancelation purposes. Furthermore, keeping the ordinary chiral quark charge assignments under the extended color gauge group in their most general form, the framework (effectively) captures a large class of models available within the literature. This contribution summarizes the current formal and phenomenological constraints on the free parameter space of the theory, as well as the LHC $\sqrt{s}=14$ TeV prospects for discovering its heavy scalar. The model is well-constrained and highly predictive; in particular, it is shown that the parameter space can be thoroughly probed by the LHC and the next generation hadron colliders, making it a promising beyond the SM candidate for exploration. In addition, the significance of the NLO corrections to the coloron production cross section are discussed.

    hep-phhep-exPoS(2015)·0 citations
21. 21*

    Coulomb gluons and the ordering variable

    René Ángeles-Martínez🇬🇧 · Jeffrey R. Forshaw🇬🇧 · Michael H. Seymour🇬🇧

    We study in detail the exchange of a Coulomb (Glauber) gluon in the first few orders of QCD perturbation theory in order to shed light on their accounting to all orders. We find an elegant cancellation of graphs that imposes a precise ordering on the transverse momentum of the exchanged Coulomb gluon.

    hep-phJHEP(2015)·20 citations
22. 22*

    Large-N(c) limit reduces the number of independent few-body parity-violating low-energy constants in pionless effective field theory

    Matthias R. Schindler🇺🇸 · Roxanne P. Springer🇺🇸 · Jared Vanasse🇺🇸

    The symmetries of the Standard Model dictate that for very low energies, where nucleon dynamics can be described in terms of a pionless effective field theory, the leading-order parity-violating nucleon-nucleon Lagrangian contains five independent unknown low-energy constants (LECs). We find that imposing the approximate symmetry of QCD that appears when the number of colors N(c) becomes large reduces the number of independent LECs to two at leading order in the combined pionless effective field theory and large-N(c) expansions. We also find a relation between the two isoscalar LECs in the large-N(c) limit. This has important implications for the number of experiments and/or lattice calculations necessary to confirm this description of physics.

    ↳ nucl-thhep-phPRC(2016)·43 citations
23. 23*

    S-Duality and Helicity Amplitudes

    Kitran Colwell🇺🇸 · John Terning🇺🇸

    We examine interacting Abelian theories at low energies and show that holomorphically normalized photon helicity amplitudes transform into dual amplitudes under SL(2,Z) as modular forms with weights that depend on the number of positive and negative helicity photons and on the number of internal photon lines. Moreover, canonically normalized helicity amplitudes transform by a phase, so that even though the amplitudes are not duality invariant, their squares are duality invariant. We explicitly verify the duality transformation at one loop by comparing the amplitudes in the case of an electron and the dyon that is its SL(2,Z) image, and extend the invariance of squared amplitudes order by order in perturbation theory. We demonstrate that S-duality is property of all low-energy effective Abelian theories with electric and/or magnetic charges and see how the duality generically breaks down at high energies.

    ↳ hep-thhep-phJHEP(2016)·22 citations
24. 24*

    Axion Cosmology

    David J. E. Marsh🇬🇧

    1. Introduction 2. Models: the QCD axion; the strong CP problem; PQWW, KSVZ, DFSZ; anomalies, instantons and the potential; couplings; axions in string theory 3. Production and I.C.'s: SSB and non-perturbative physics; the axion field during inflation and PQ SSB; cosmological populations - decay of parent, topological defects, thermal production, vacuum realignment 4. The Cosmological Field: action; background evolution; misalignment for QCD axion and ALPs; cosmological perturbation theory - i.c.'s, early time treatment, axion sound speed and Jeans scale, transfer functions and WDM; the Schrodinger picture; simualting axions; BEC 5. CMB and LSS: Primary anisotropies; matter power; combined constraints; Isocurvature and inflation 6. Galaxy Formation; halo mass function; high-z and the EOR; density profiles; the CDM small-scale crises 7. Accelerated expansion: the c.c. problem; axion inflation (natural and monodromy) 8. Gravitational interactions with black holes and pulsars 9. Non-gravitational interactions: stellar astrophysics; LSW; vacuum birefringence; axion forces; direct detection with ADMX and CASPEr; Axion decays; dark radiation; astrophysical magnetic fields; cosmological birefringence 10. Conclusions A Theta vacua of gauge theories B EFT for cosmologists C Friedmann equations D Cosmological fluids E Bayes Theorem and priors F Degeneracies and sampling G Sheth-Tormen HMF

    ↳ astro-ph.COhep-phhep-thPhys.Rept.(2016)·2155 citations
25. 25*

    Quark Nugget Dark Matter: No contradictions with neutrino flux constraints

    Kyle Lawson🇨🇦 · Ariel R. Zhitnitsky🇨🇦

    It has recently been claimed that dark matter in form of quark nuggets cannot account for more than 20% of the dark matter density. This claim is based on constraints on the neutrino flux in 20-50 MeV range where the sensitivity of underground neutrino detectors such as Super-Kamiokande have their highest signal-to-noise ratio. We argue that this claim depends crucially on the assumption that the annihilation of visible baryons with an antiquark nugget will generate a neutrino spectrum similar to the conventional baryon-antibaryon annihilation spectrum in vacuum. However, this assumption does not hold for the nuggets in a colour superconducting phase where the lightest pseudo Goldstone mesons (the pions and Kaons) have masses in the 20 MeV range, in contrast with conventional pion mass of roughly 140 MeV. Thus, the decay of these light pseudo Goldstone bosons of the CS phase cannot produce highly energetic neutrinos in the 20-50 MeV energy range.

    ↳ astro-ph.HEhep-phPRD(2017)·19 citations
26. 26*

    Curving Yang-Mills-Higgs Gauge Theories

    Alexei Kotov🇧🇷 · Thomas Strobl🇫🇷

    Established fundamental physics can be described by fields, which are maps. The source of such a map is space-time, which can be curved due to gravity. The map itself needs to be curved in its gauge field part so as to describe interaction forces like those mediated by photons and gluons. In the present article, we permit non-zero curvature also on the internal space, the target of the field map. The action functional and the symmetries are constructed in such a way that they reduce to those of standard Yang-Mills-Higgs (YMH) gauge theories precisely when the curvature on the target of the fields is turned off. For curved targets one obtains a new theory, a curved YMH gauge theory. It realizes in a mathematically consistent manner an old wish in the community: replacing structures constants by functions depending on the scalars of the theory. In addition, we provide a simple 4d toy model, where the gauge symmetry is abelian, but turning off the gauge fields, no rigid symmetry remains---another possible manifestation of target curvature. It now remains to be seen, if internal curvature in the above sense is realized in nature. Curvature of space-time is proven, but still negligible in particle physics, except for the very early universe where quantum gravity must have played an essential role. An important question therefore is, if glimpses of target curvature can be visible in accelerator physics. We know that at contemporary energy scales, the usual (flat) standard model describes nature to a very high accuracy. Could it be that the alleged deviations in the B to D-star-tau-nu decay reported by BaBar in 2012 and recently also by LHCb are already a manifestation of target curvature? What kind of effects does target curvature have on a YMH theory in general, for what kind of effects do we need to look out for so as to detect it?

    ↳ hep-thhep-phmath-phmath.MPPRD(2015)·26 citations
27. 27*

    $A_k\bar{F}$ Chiral Gauge Theories

    Yan-Liang Shi🇺🇸 · Robert Shrock🇺🇸

    We study asymptotically free chiral gauge theories with an SU($N$) gauge group and chiral fermions transforming according to the antisymmetric rank-$k$ tensor representation, $A_k\equiv [k{]}_N$, and the requisite number, $n_{\bar{F}}$, of copies of fermions in the conjugate fundamental representation, $\bar{F}\equiv {\overline{[1]}}_N$, to render the theories anomaly-free. We denote these as $A_k\bar{F}$ theories. We take $N\ge 2k+1$ so that $n_{\bar{F}}\ge 1$. The $A_2\bar{F}$ theories form an infinite family with $N\ge 5$, but we show that the $A_3\bar{F}$ and $A_4\bar{F}$ theories are only asymptotically free for $N$ in the respective ranges $7\le N\le 17$ and $9\le N\le 11$, and that there are no asymptotically free $A_k\bar{F}$ theories with $k\ge 5$. We investigate the types of ultraviolet to infrared evolution for these $A_k\bar{F}$ theories and find that, depending on $k$ and $N$, they may lead to a non-Abelian Coulomb phase, or may involve confinement with massless gauge-singlet composite fermions, bilinear fermion condensation with dynamical gauge and global symmetry breaking, or formation of multifermion condensates that preserve the gauge symmetry. We also show that there are no asymptotically free, anomaly-free SU($N$) $S_k\bar{F}$ chiral gauge theories with $k\ge 3$, where $S_k$ denotes the rank-$k$ symmetric representation.

    ↳ hep-thhep-phPRD(2015)·29 citations
28. 28*

    Hydrodynamics of ultra-relativistic bubble walls

    Leonardo Leitao🇦🇷 · Ariel Megevand🇦🇷

    In cosmological first-order phase transitions, gravitational waves are generated by the collisions of bubble walls and by the bulk motions caused in the fluid. A sizeable signal may result from fast-moving walls. In this work we study the hydrodynamics associated to the fastest propagation modes, namely, ultra-relativistic detonations and runaway solutions. We compute the energy injected by the phase transition into the fluid and the energy which accumulates in the bubble walls. We provide analytic approximations and fits as functions of the net force acting on the wall, which can be readily evaluated for specific models. We also study the back-reaction of hydrodynamics on the wall motion, and we discuss the extrapolation of the friction force away from the ultra-relativistic limit. We use these results to estimate the gravitational wave signal from detonations and runaway walls.

    ↳ astro-ph.COhep-phNPB(2016)·19 citations
29. 29*

    Mass spectra of mesons containing charm quarks - continuum limit results from twisted mass fermions

    Krzysztof Cichy🇩🇪 · Martin Kalinowski🇩🇪 · Marc Wagner🇩🇪

    We present results from an ongoing computation of masses of $D$ mesons, $D_s$ mesons and charmonium, including both ground states and several parity and angular momentum excitations. We employ 2+1+1 flavours of dynamical maximally twisted mass fermions at three lattice spacings and three $u/d$ quark masses at each lattice spacing. We consider different combinations of valence quark discretizations, with either identical or opposite signs in front of the twisted mass terms. In the end, our setup allows for a good control of different kinds of systematic effects, in particular the quark mass dependence of the resulting meson masses and cut-off effects. We obtain good agreement with experiment for the majority of states and we discuss improvements that will be made to finalize the analysis.

    ↳ hep-lathep-exhep-phPoS(2015)·5 citations
30. 30*

    On general ultraviolet properties of a class of confining propagators

    M. A. L. Capri🇧🇷 · M. S. Guimaraes🇧🇷 · I. Justo🇧🇷 · L. F. Palhares🇧🇷 · S. P. Sorella🇧🇷

    We study the ultraviolet properties of theories whose fundamental fields display a confining, Gribov-type, propagator. These are propagators that exhibit complex poles and violate positivity, thus precluding a physical propagating particle interpretation. We show that the properties of this type of confining propagators do not change the ultraviolet behavior of the theory, in the sense that no new ultraviolet primitive divergences are generated, thus securing the renormalizability of these confining theories. We illustrate these properties by studying a variety of models, including bosonic and fermionic confined degrees of freedom. The more intricate case of Super Yang-Mills with $\mathcal{N}=1$ supersymmetries in the Wess-Zumino gauge is taken as example in order to prove these statements to all orders by means of the algebraic renormalization set up.

    ↳ hep-thhep-phnucl-thEPJC(2016)·14 citations
31. 31*

    Q-lumps on a Domain Wall with a Spin-Orbit Interaction

    N. Blyankinshtein🇷🇺

    The nonlinear O(3) sigma-model in (2+1) dimensions with an additional potential term admits solutions called Q-lumps, having both topological and Noether charges. We consider in 3+1-dimensional spacetime the theory with Q-lumps on a domain wall in the presence of spin-orbit interaction in the bulk and find interaction effects for a two-particle solution through perturbation theory and adiabatic approximation.

    ↳ hep-thcond-mat.supr-conhep-phPRD(2016)·10 citations
32. 32*

    Searching for Dark Matter Annihilation into Neutrinos with Super-Kamiokande

    Katarzyna Frankiewicz (Super-Kamiokande Collaboration)🇵🇱

    This work presents indirect searches for dark matter (DM) as WIMPs (Weakly Interacting Massive Particles) using neutrino data recorded by the Super-Kamiokande detector from 1996 to 2014. The results of the search for WIMP-induced neutrinos from the Sun and the Milky Way are discussed. We looked for an excess of neutrinos from the Sun/Milky Way direction compared to the expected atmospheric neutrino background. Event samples including both electron and muon neutrinos covering a wide range of neutrino energies (GeV to TeV) were used, with sensitivity to WIMP masses down to tens of GeV. Various WIMP annihilation modes were taken into account in the analyses.

    ↳ hep-exhep-ph41 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.