Tue·Oct 4, 2016Tuesday·October 4, 2016

1. 01*

   Lepton-Flavored Electroweak Baryogenesis

   Huai-Ke Guo🇨🇳 · Ying-Ying Li🇨🇳 · Tao Liu🇨🇳 · Michael Ramsey-Musolf🇺🇸 · Jing Shu🇨🇳

   We explore lepton-flavored electroweak baryogenesis, driven by CP-violation in leptonic Yukawa sector, using the $\tau -\mu$ system in the two Higgs doublet model as an example. This setup generically yields, together with the flavor-changing decay $h\to \tau \mu$, a tree-level Jarlskog-invariant that can drive dynamical generation of baryon asymmetry during a first-order electroweak phase transition and results in CP-violating effect in the decay $h\to \tau \tau$. We find that the observed baryon asymmetry can be generated in parameter space compatible with current experimental results for the decays $h\to \tau \mu$, $h\to \tau \tau$ and $\tau \to \mu \gamma$, as well as the present bound on the electric dipole moment of the electron. The baryon asymmetry generated is intrinsically correlated with the CP-violating decay $h\to \tau \tau$ and the flavor-changing decay $h\to \tau \mu$, which thus may serve as "smoking guns" to test lepton-flavored electroweak baryogenesis.

   hep-phPRD(2017)·67 citations
2. 02*

   Exclusive vector meson photoproduction at the LHC and the FCC: A closer look on the final state

   G. Gil da Silveira🇧🇷 · V. P. Goncalves🇧🇷 · M. M. Jaime🇧🇷

   Over the past years the LHC experiments have reported experimental evidences for processes associated to photon-photon and photon-hadron interactions, showing their potential to investigate the production of low- and high-mass systems in exclusive events. In the particular case of the photoproduction of vector mesons, the experimental study of this final state is expected to shed light on the description of the QCD dynamics at small values of the Bjorken-$x$ variable. In this paper we extend previous studies for the exclusive $J/\Psi$ and ${\rm Y}$ photoproduction in $pp$ collisions based on the nonlinear QCD dynamics by performing a detailed study of the final state distributions that can be measured experimentally at the LHC and at the Future Circular Collider. Predictions for the rapidity and transverse momentum distributions of the vector mesons and of final-state dimuons are presented for $pp$ collisions at $\sqrt{s}=$ 7, 13, and 100 TeV.

   hep-phhep-exPRD(2017)·8 citations
3. 03*

   Analyzing the CP Nature of a New Scalar Particle via S->Zh Decay

   Martin Bauer (U. Heidelberg)🇩🇪 · Matthias Neubert (MITP and JGU Mainz, Cornell U.)🇩🇪 · Andrea Thamm (JGU Mainz)🇩🇪

   Scalar particles $S$ which are singlets under the Standard Model gauge group are generic features of many models of fundamental physics, in particular as possible mediators to a hidden sector. We show that the decay $S\to Zh$ provides a powerful probe of the CP nature of the scalar, because it is allowed only if $S$ has CP-odd interactions. We perform a model-independent analysis of this decay using an effective Lagrangian and compute the relevant Wilson coefficients arising from integrating out heavy fermions to one-loop order.

   hep-phPRL(2016)·44 citations
4. 04*

   The ccbar Pentaquarks by a Quark Model

   Sachiko Takeuchi🇯🇵 · Makoto Takizawa🇯🇵

   Recent LHCb experiments have shown us that there are two resonances in the $J/\psi p$ channel in the ${\Lambda }_b$ decay, whose spin and parity are most probably (3/2${}^{-}$ 5/2${}^{+}$). In this work, we investigate the $I(J^P)=1/2(1/2^{-})$, $1/2(3/2^{-})$, and $1/2(5/2^{-})$ $uudc\bar{c}$ pentaquark states by employing the quark cluster model. It is found that the color-octet isospin-1/2 spin-3/2 $uud$ configuration gives an attraction to such five-quark systems. This configuration together with the color-octet $c\bar{c}$ pair gives structures around the ${\Sigma }_c^{(\ast )}\bar{D}{}^{(\ast )}$ thresholds: one bound state, two resonances, and one large cusp are found in the $uudc\bar{c}$ negative parity channels. We argue that these resonances and cusp may correspond to, or combine to form, the negative parity pentaquark peak observed by LHCb.

   hep-phJPS Conf.Proc.(2017)·1 citation
5. 05*

   Study of the lowest tensor and scalar resonances in the $\tau \to \pi \pi \pi {\nu }_{\tau }$ decay

   O. Shekhovtsova🇵🇱 · J.J. Sanz-Cillero🇪🇸 · T. Przedzinski🇵🇱

   In this note we present a new parametrization of the hadronic current for the decay $\tau \to \pi \pi \pi {\nu }_{\tau }$ derived from the chiral lagrangian with explicit inclusion of resonances. We have included both scalar, vector and axial-vector resonances. For the first time, the lowest tensor resonance ($f_2(1270)$) is included as well. Both single and double-resonance contributions to the hadronic form factors are taken into account. To satisfy the correct high energy behaviour of the hadronic form factors, constraints on numerical values of the vertex constants are obtained.

   hep-phEPJ Web Conf.(2016)·1 citation
6. 06*

   Radiative $h_{c/b}$ decays to $\eta$ or ${\eta }^{\prime }$

   Ruilin Zhu🇨🇳 · Jian-Ping Dai🇨🇳

   Motivated by recent measurements of the radiative decay rates of the \emph{P}-wave spin singlet charmonium $h_c$ to the light meson $\eta$ or ${\eta }^{\prime }$ by the BESIII Collaboration, we investigate the decay rates of these channels at order $\alpha {\alpha }_s^4$. The photon is radiated mainly from charm quark pairs in the lowest order Feynman diagrams, since the diagrams where a photon radiated from light quarks are suppressed by ${\alpha }_s$ or the relative charm quark velocity $v$, due to Charge parity conservation. The form factors of two gluons to $\eta$ or ${\eta }^{\prime }$ are employed, which are the major mechanism for $\eta$ and ${\eta }^{\prime }$ productions. $\eta ({\eta }^{\prime })$ is treated as a light cone object when we consider that the parent charmonium mass is much heavier than that of the final light meson. We obtain the branching ratio $\mathcal{B}(h_c\to \gamma {\eta }^{\prime })=(1.94_{-0.51}^{+0.70})\times 10^{-3}$ in the nonrelativistic QCD approach, which is in agreement with the BESIII measurement. The prediction of the branching ratio of $h_c\to \gamma \eta$ is also within the range of experimental error after including the larger uncertainty of the total decay width ${\Gamma }_{h_c}$. The applications of these formulae to the radiative decays to $\eta ({\eta }^{\prime })$ of the \emph{P}-wave spin singlet bottomonium $h_b(nP)$ are presented. These studies will shed some light on the $\eta -{\eta }^{\prime }$ mixing effects, the flavor SU(3) symmetry breaking, as well as the nonperturbative dynamics of charmonium and bottomonium.

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

   A neutrino mixing model based on an $A_4\times Z_3\times Z_4$ flavour symmetry

   Nguyen Anh Ky🇻🇳 · Phi Quang Van🇻🇳 · Nguyen Thi Hong Van🇻🇳

   A model of a neutrino mixing with an $A_4\times Z_3\times Z_4$ flavour symmetry is suggested. In addition to the standard model fields, the present model contains six new fields which transform under different representations of $A_4\times Z_3\times Z_4$. The model is constructed to slightly deviate from a tri-bi-maximal model in agreement with the current experimental data, thus, all analysis can be done in the base of the perturbation method. Within this model, as an application, a relation between the mixing angles (${\theta }_{12},{\theta }_{23},{\theta }_{13}$) and the Dirac CP-violation phase (${\delta }_{CP}$) is established. This relation allows a prediction of ${\delta }_{CP}$ and the Jarlskog parameter ($J_{CP}$). The predicted value ${\delta }_{CP}$ is in the 1$\sigma$ region of the global fit for both the normal- and inverse neutrino mass ordering and gives $J_{CP}$ to be within the bound $|J_{CP}|\le 0.04$. For an illustration, the model is checked numerically and gives values of the neutrino masses (of the order of 0.1 eV) and the mixing angle ${\theta }_{13}$ (about $9^{\circ }$) very close to the current experimental data.

   hep-phPRD(2016)·8 citations
8. 08*

   Neutral Naturalness with Bifundamental Gluinos

   Tony Gherghetta🇺🇸 · Minh Nguyen🇺🇸 · Zoe Thomas🇺🇸

   We study constraints on one-loop neutral naturalness at the LHC by considering gluon partners which are required to ameliorate the tuning in the Higgs mass-squared arising at two loops. This is done with a simple orbifold model of folded supersymmetry which not only contains color-neutral stops but also bifundamental gluinos that are charged under the Standard Model color group $SU(3{)}_C$ and a separate $SU(3{)}_C^{\prime }$ group. The bifundamental gluinos reduce the Higgs mass tuning at two loops and maintain naturalness provided the gluinos are lighter than approximately 1.9 TeV for a 5 TeV cutoff scale. Limits from the LHC already forbid bifundamental gluinos below 1.4 TeV, and other non-colored states such as electroweakinos, $Z^{\prime }$ bosons and dark sector bound states may be probed at future colliders. The search for bifundamental gluinos therefore provides a direct probe of one-loop neutral naturalness that can be fully explored at the LHC.

   hep-phhep-thPRD(2016)·7 citations
9. 09*

   Next-to-leading order QCD corrections to paired $B_c$ production in $e^{+}{e}^{-}$ annihilation

   A.V. Berezhnoy🇷🇺 · A.K. Likhoded🇷🇺 · A.I. Onishchenko🇷🇺 · S.V. Poslavsky🇷🇺

   We present theoretical analysis of paired $B_c$ mesons production in $e^{+}{e}^{-}$ annihilation at different energy scales taking into account full next-to-leading order QCD corrections. Both possible electroweak channels are considered: production via virtual photon and via virtual $Z$-boson. We study in detail the role of radiative QCD corrections, which were found to be significant especially at low energies. It is shown that the contribution from $Z$-boson is significant at high energies ($\sqrt{s}>M_Z/2$) especially in the case of paired production of pseudo-scalar and vector ($B_c+B_c^{\ast }$) mesons. Azimuthal asymmetry induced by a $P$-violating weak interaction with $Z$-boson is also analyzed.

   hep-phNPB(2017)·24 citations
10. 10*

    F(750), We Miss You, as Bound State of 6 Top and 6 Anti top

    Holger Frits Bech Nielsen🇩🇰

    We collect and estimate support for our long speculated "multiple point principle" saying that there should be several vacua all having (compared to the scales of high energy physics) very low energy densities. In pure Standard Model we suggest there being three by "multiple point principle" low energy density vacua, "present", "condensate" and "high field" vacuum. We fit the mass of the in our picture since long speculated bound state of six top and six anti top quarks in three quite {\em independent ways} and get remarkably within our crude accuracy the {\em same} mass in all three fits! The new point of the present article is to estimate the bound state mass in what we could call a bag model estimation. The two other fits, which we review, obtain the mass of the bound state by fitting to the multiple point principle prediction of degenerate vacua. Our remarkable agreement of our three mass-fits can be interpreted to mean, that we have calculated at the end the energy densities of the two extra speculated vacua and found that they are indeed very small!. Unfortunately the recently much discussed statistical fluctuation peak F(750) has now been revealed to be just a fluctuation, very accidentally matches our fitted mass of the bound state remarkably well with the mass of this fluctuation 750 GeV.

    hep-phInt.J.Mod.Phys.A(2016)·5 citations
11. 11*

    Implications of Higgs data for the electroweak chiral Lagrangian

    Alejandro Celis🇩🇪

    In this talk I discuss the interpretation of LHC Higgs measurements within the electroweak chiral Lagrangian, paying particular attention to the role of power counting.

    hep-phhep-ex0 citations
12. 12*

    Vector meson condensation in a pion superfluid

    Tomas Brauner🇳🇴 · Xu-Guang Huang🇨🇳

    We revisit the suggestion that charged rho-mesons undergo Bose-Einstein condensation in isospin-rich nuclear matter. Using a simple version of the Nambu-Jona-Lasinio (NJL) model, we conclude that rho-meson condensation is either avoided or postponed to isospin chemical potentials much higher than the rho-meson mass as a consequence of the repulsive interaction with the preformed pion condensate. In order to support our numerical results, we work out a linear sigma model for pions and rho-mesons, showing that the two models lead to similar patterns of medium dependence of meson masses. As a byproduct, we analyze in detail the mapping between the NJL model and the linear sigma model, focusing on conditions that must be satisfied for a quantitative agreement between the models.

    hep-phhep-thnucl-thPRD(2016)·27 citations
13. 13*

    New physics facing LFU and LFV tests in B physics

    Nejc Kosnik🇸🇮

    Lepton flavor universality in the Standard Model and hints of its violation in neutral ($R_K$) and charged currents $(R_{D^{(\ast )}})$ in $B$ decays are presented. We discuss model independent features as well as several leptoquark scenarios which are well suited to fit current values of $R_K$ and/or $R_{D^{(\ast )}}$.

    hep-phPoS(2016)·3 citations
14. 14*

    The uncertainty of parton distribution functions due to physical observables in a global analysis

    Alireza Aleedaneshvar🇮🇷 · Muhammad Goharipour🇮🇷 · Saeedeh Rostami🇮🇷

    The recent measurement of the differential $\gamma +c$-jet cross section, performed at the Tevatron collider in Run II by the D0 collaboration, is studied in a next-to-leading order (NLO) global QCD analysis to assess its impact on the proton parton distribution functions (PDFs). We show that these data lead to a significant change on the gluon and charm quark distributions. We demonstrate also that there is an inconsistency between the new high precision HERA I+II combined data and Tevatron measurement. Moreover, in this study we investigate the impact of older EMC measurements of charm structure function $F_c^2$ on the PDFs and compare the results with those gaining from the analysis of Tevatron data. We show that both of them have a same impact on PDFs, and thus can be recognized as same evidences for inefficiency of perturbative QCD in dealing with the charm production in some kinematic regions.

    hep-phCPC(2017)·4 citations
15. 15*

    Quark-flavour violating Higgs decays to charm and bottom pairs in the MSSM

    E. Ginina🇦🇹 · H. Eberl🇦🇹 · A. Bartl🇦🇹 · K. Hidaka🇯🇵 · W. Majerotto🇦🇹

    We calculate the decay width of $h^0\to b\bar{b}$ in the Minimal Supersymmetric Standard Model (MSSM) with quark-flavour violation (QFV) at full one-loop level. The effect of $\tilde{c}-\tilde{t}$ mixing and $\tilde{s}-\tilde{b}$ mixing is studied taking into account the constraints from the B-meson data. We discuss and compare in detail the decays $h^0\to c\bar{c}$ and $h^0\to b\bar{b}$ within the framework of the perturbative mass insertion technique using the Flavour Expansion Theorem. The deviation of both decay widths from the Standard Model results can be quite large. While in $h^0\to c\bar{c}$ it is almost entirely due to the flavour violating part of the MSSM, in $h^0\to b\bar{b}$ it is mainly due to the flavour conserving part. Nevertheless, $\Gamma (h^0\to b\bar{b})$ can fluctuate up to $\sim 7\%$ due to QFV chargino exchange with large $\tilde{c}-\tilde{t}$ mixing. due to QFV chargino exchange with large $\tilde{c}-\tilde{t}$ mixing.

    hep-phNucl.Part.Phys.Proc.(2017)·0 citations
16. 16*

    Bs to mu mu gamma from Bs to mu mu

    Francesco Dettori🇨🇭 · Diego Guadagnoli🇫🇷 · Meril Reboud🇫🇷

    The Bs to mu mu gamma decay offers sensitivity to a wider set of effective operators than its non-radiative counterpart Bs to mu mu, and a set that is interesting in the light of present-day discrepancies in flavour data. On the other hand, the direct measurement of the Bs to mu mu gamma decay poses challenges with respect to the Bs to mu mu one. We present a novel strategy to search for Bs to mu mu gamma decays in the very event sample selected for Bs to mu mu searches. The method consists in extracting the Bs to mu mu gamma spectrum as a "contamination" to the Bs to mu mu one, as the signal window for the latter is extended downward with respect to the peak region. We provide arguments for the actual practicability of the method already on Run-2 data of the LHC.

    hep-phPLB(2017)·32 citations
17. 17*

    Gauge Coupling Unification with Hidden Photon, and Minicharged Dark Matter

    Ryuji Daido🇯🇵 · Fuminobu Takahashi🇯🇵 · Norimi Yokozaki🇯🇵

    We show that gauge coupling unification is realized with a greater accuracy in the presence of a massless hidden photon which has a large kinetic mixing with hypercharge. We solve the renormalization group equations at two-loop level and find that the GUT unification scale is around $10^{16.5}$ GeV which sufficiently suppresses the proton decay rate, and that the unification is essentially determined by the kinetic mixing only, and it is rather insensitive to the hidden gauge coupling or the presence of vector-like matter fields charged under U(1)${}_H$ and/or SU(5). Matter fields charged under the unbroken hidden U(1)${}_H$ are stable and they contribute to dark matter. Interestingly, they become minicharged dark matter which carries a small but non-zero electric charge, if the hidden gauge coupling is tiny. The minicharged dark matter is a natural outcome of the gauge coupling unification with a hidden photon.

    hep-phhep-exPLB(2017)·5 citations
18. 18*

    Exploring collider signatures of the inert Higgs doublet model

    Amitava Datta🇮🇳 · Nabanita Ganguly🇮🇳 · Najimuddin Khan🇮🇳 · Subhendu Rakshit🇮🇳

    We revisit the multilepton ($ml$) + $E{/}_T$ + $X$ signatures of the Inert Doublet Model (IDM) of dark matter in future LHC experiments for $m=$ 3, 4 and simulate, for the first time, the $m=5$ case. Here $X$ stands for any number of jets. We illustrate these signals with benchmark points consistent with the usual constraints like unitarity, perturbativity, the precision electroweak data, the observed dark matter relic density of the Universe and, most importantly, the stringent LHC constraints from the post Higgs ($h$) discovery era like the measured $M_h$ and the upper bound on the invisible width of $h$ decay which were not included in earlier analyses of multilepton signatures. We find that if the IDM model is embedded in a grand dessert scenario so that the unitarity constraint holds up to a very high scale, the whole of the highly restricted parameter space allowed by the above constraints can be probed at the LHC via the $3l$ signal for an integrated luminosity $\sim 3000{\mathrm{fb}}^{-1}$. On the other hand, if any new physics shows up at a scale $\sim$ 10~TeV, only a part of the enlarged allowed parameter space can be probed. The $4l$ and $5l$ signals can help to discriminate among different IDM scenarios as and when sufficient integrated luminosity accumulates.

    hep-phPRD(2017)·87 citations
19. 19*

    From Type II string theory towards BSM/dark sector physics

    Gabriele Honecker🇩🇪

    Four-dimensional compactifications of string theory provide a controlled set of possible gauge representations accounting for BSM particles and dark sector components. In this review, constraints from perturbative Type II string compactifications in the geometric regime are discussed in detail and then compared to results from heterotic string compactifications and non-perturbative/non-geometric corners. As a prominent example, an open string realization of the QCD axion is presented. The status of deriving the associated low-energy effective action in four dimensions is discussed and open avenues of major phenomenological importance are highlighted. As examples, a mechanism of closed string moduli stabilization by D-brane backreaction as well as one-loop threshold corrections to the gauge couplings and balancing a low string scale $M_{\text{string}}$ with unisotropic compact dimensions are discussed together with implications on potential future new physics observations. For illustrative purposes, an explicit example of a globally consistent D6-brane model with MSSM-like spectrum on $T^6/({\mathbb{Z}}_2\times {\mathbb{Z}}_6\times \Omega \mathcal{R})$ is presented.

    ↳ hep-thhep-phInt.J.Mod.Phys.A(2016)·11 citations
20. 20*

    Thermal Inflation with a Thermal Waterfall Scalar Field Coupled to a Light Spectator Scalar Field

    Arron Rumsey🇬🇧

    This thesis begins with an introduction to the state of the art of modern Cosmology. The field of Particle Cosmology is then introduced and explored, in particular with regard to the study of cosmological inflation. We then introduce a new model of Thermal Inflation, in which the mass of the thermal waterfall field responsible for the inflation is dependent on a light spectator scalar field. The model contains a variety of free parameters, two of which control the power of the coupling term and the non-renormalizable term. We use the $\delta N$ formalism to investigate the "end of inflation" and modulated decay scenarios in turn to see whether they are able to produce the dominant contribution to the primordial curvature perturbation $\zeta$. We constrain the model and then explore the parameter space. We explore key observational signatures, such as non-Gaussianity, the scalar spectral index and the running of the scalar spectral index. We find that for some regions of the parameter space, the ability of the model to produce the dominant contribution to $\zeta$ is excluded. However, for other regions of the parameter space, we find that the model yields a sharp prediction for a variety of parameters within the model.

    ↳ astro-ph.COgr-qchep-phhep-th1 citation
21. 21*

    Higgs Potential from Derivative Interactions

    A. Quadri🇮🇹

    A formulation of the linear $\sigma$ model with derivative interactions is studied. The classical theory is on-shell equivalent to the $\sigma$ model with the standard quartic Higgs potential. The mass of the scalar mode only appears in the quadratic part and not in the interaction vertices, unlike in the ordinary formulation of the theory. Renormalization of the model is discussed. A non power-counting renormalizable extension, obeying the defining functional identities of the theory, is presented. This extension is physically equivalent to the tree-level inclusion of a dimension six effective operator ${\partial }_{\mu }({\Phi }^{†}\Phi ){\partial }^{\mu }({\Phi }^{†}\Phi )$. The resulting UV divergences are arranged in a perturbation series around the power-counting renormalizable theory. The application of the formalism to the Standard Model in the presence of the dimension-six operator ${\partial }_{\mu }({\Phi }^{†}\Phi ){\partial }^{\mu }({\Phi }^{†}\Phi )$ is discussed.

    ↳ hep-thhep-phInt.J.Mod.Phys.A(2017)·13 citations
22. 22*

    Covariant Quantization of CPT-violating Photons

    D. Colladay🇺🇸 · P. McDonald🇺🇸 · J. P. Noordmans🇵🇹 · R. Potting🇵🇹

    We perform the covariant canonical quantization of the CPT- and Lorentz-symmetry-violating photon sector of the minimal Standard-Model Extension, which contains a general (timelike, lightlike, or spacelike) fixed background tensor $k_{AF}^{\mu }$. Well-known stability issues, arising from complex-valued energy states, are solved by introducing a small photon mass, orders of magnitude below current experimental bounds. We explicitly construct a covariant basis of polarization vectors, in which the photon field can be expanded. We proceed to derive the Feynman propagator and show that the theory is microcausal. Despite the occurrence of negative energies and vacuum-Cherenkov radiation, we do not find any runaway stability issues, because the energy remains bounded from below. An important observation is that the ordering of the roots of the dispersion relations is the same in any observer frame, which allows for a frame-independent condition that selects the correct branch of the dispersion relation. This turns out to be critical for the consistency of the quantization. To our knowledge, this is the first system for which quantization has consistently been performed, in spite of the fact that the theory contains negative energies in some observer frames.

    ↳ hep-thhep-phPRD(2017)·26 citations
23. 23*

    Minimal inflationary cosmologies and constraints on reheating

    Debaprasad Maity🇮🇳 · Pankaj Saha🇮🇳

    With the growing consensus on simple power law inflation models not being favored by the PLANCK observation, dynamics for the non-standard form of the inflaton potential gain significant interest in the recent past. In this paper, we analyze in great detail classes of phenomenologically motivated inflationary models with non-polynomial potential which are the generalization of the potential introduced in \cite{mhiggs}. After the end of inflation, inflaton field will coherently oscillate around its minimum. Depending upon the initial amplitude of the oscillation and coupling parameters standard parametric resonance phenomena will occur. Therefore, we will study how the inflationary model parameters play an important role in understanding the resonant structure of our model under study. Subsequently, the universe will go through the perturbative reheating phase. However, without any specific model consideration, we further study the constraints on our models based on model independent reheating constraint analysis.

    ↳ astro-ph.COhep-ph7 citations
24. 24*

    Strangeness at finite temperature from Lattice QCD

    Jacquelyn Noronha-Hostler🇺🇸 · Rene Bellwied🇺🇸 · Jana Gunther🇩🇪 · Paolo Parotto🇺🇸 · Attila Pasztor🇩🇪 · Israel Portillo Vazquez🇺🇸 · Claudia Ratti🇺🇸

    The precision reached by recent lattice QCD results allows for the first time to investigate whether the measured hadronic spectrum is missing some additional strange states, which are predicted by the Quark Model but have not yet been detected. This can be done by comparing some sensitive thermodynamic observables from lattice QCD to the predictions of the Hadron Resonance Gas model (with the inclusion of decays [3]). We propose a set of specific observables, defined as linear combinations of conserved charge fluctuations, which allow to investigate this issue for baryons containing one or more strange quarks separately. Applications of these observables to isolate the multiplicity fluctuations of kaons from lattice QCD, and their comparison with the experimental results, are also discussed.

    ↳ nucl-thhep-lathep-phJ.Phys.Conf.Ser.(2017)·3 citations
25. 25*

    Probing the nature of phases across the phase transition at finite isospin chemical potential

    Gunnar S. Bali🇩🇪 · G. Endrodi🇩🇪 · Rajiv V. Gavai🇮🇳 · N. Mathur🇮🇳

    We compare the low eigenvalue spectra of the Overlap Dirac operator on two sets of configurations at ${\mu }_I/{\mu }_I^c$ = 0.5 and 1.5 generated with dynamical staggered fermions at these isospin chemical potential on $24^3\times 6$ lattices. We find very small changes in the number of zero modes and low lying modes which is in stark contrast with those across the corresponding finite temperature phases where one sees a drop across the phase transition. Possible consequences are discussed.

    ↳ hep-lathep-phnucl-thActa Phys.Polon.Supp.(2017)·6 citations
26. 26*

    SU(2N_F) symmetry of QCD at high temperature and its implications

    L. Ya. Glozman🇦🇹

    If above a critical temperature not only the SU(N_F)_L \times SU(N_F)_R chiral symmetry of QCD but also the U(1)_A symmetry is restored, then the actual symmetry of the QCD correlation functions and observables is SU(2N_F). Such a symmetry prohibits existence of deconfined quarks and gluons. Hence QCD at high temperature is also in the confining regime and elementary objects are SU(2N_F) symmetric "hadrons" with not yet known properties.

    ↳ hep-lathep-phhep-thnucl-thActa Phys.Polon.Supp.(2017)·22 citations
27. 27*

    Instability of Chern-Simons Theory with Fermions at Large N

    Chen Zhang🇨🇦

    We study the (in)stability around the dynamical gap solution of the $U(N)$ Chern-Simons gauge theory with fundamental fermions (massless or massive) coupled in $D=3$ at large $N$. Explicit analyses on both the Auxiliary-Field (AF) and the Cornwall-Jackiw-Tomboulis (CJT) effective potentials are given. In both approaches we manage to analytically identify the saddle-point instability around the gap solution. We also give a comparison with the QCD-like theories. This study can help understanding the scale symmetry breaking picture of this theory.

    ↳ hep-thhep-ph0 citations
28. 28*

    Scheme-Independent Series Expansions at an Infrared Zero of the Beta Function in Asymptotically Free Gauge Theories

    T. A. Ryttov🇩🇰 · R. Shrock🇺🇸

    We consider an asymptotically free vectorial gauge theory, with gauge group $G$ and $N_f$ fermions in a representation $R$ of $G$, having an infrared (IR) zero in the beta function at ${\alpha }_{IR}$. We present general formulas for scheme-independent series expansions of quantities, evaluated at ${\alpha }_{IR}$, as powers of an $N_f$-dependent expansion parameter, ${\Delta }_f$. First, we apply these to calculate the derivative $d\beta /d\alpha$ evaluated at ${\alpha }_{IR}$, denoted ${\beta }_{IR}^{\prime }$, which is equivalent to the anomalous dimension of the $\mathrm{Tr}(F_{\mu \nu }{F}^{\mu \nu })$ operator, to order ${\Delta }_f^4$ for general $G$ and $R$, and to order ${\Delta }_f^5$ for $G=\mathrm{SU}(3)$ and fermions in the fundamental representation. Second, we calculate the scheme-independent expansions of the anomalous dimension of the flavor-nonsinglet and flavor-singlet bilinear fermion antisymmetric Dirac tensor operators up to order ${\Delta }_f^3$. The results are compared with rigorous upper bounds on anomalous dimensions of operators in conformally invariant theories. Our other results include an analysis of the limit $N_c\to \infty$, $N_f\to \infty$ with $N_f/N_c$ fixed, calculation and analysis of Padé approximants, and comparison with conventional higher-loop calculations of ${\beta }_{IR}^{\prime }$ and anomalous dimensions as power series in $\alpha$.

    ↳ hep-thhep-lathep-phPRD(2016)·48 citations
29. 29*

    Spectrum and Structure of Excited Baryons with CLAS

    Volker D. Burkert🇺🇸

    In this contribution we discuss recent results in light quark baryon spectroscopy involving CLAS data and higher level analysis results from the partial wave analysis by the Bonn-Gatchina group. New baryon states were discovered largely based on the open strangeness production channels $\gamma p\to K^{+}\Lambda$ and $\gamma p\to K^{+}{\Sigma }^0$. The data illustrate the great potential of the kaon-hyperon channel in the discovery of higher mass baryon resonances in s-channel production. Other channels with discovery potential, such as $\gamma p\to p\omega$ and $\gamma p\to \varphi p$ are also discussed. In the second part I will demonstrate on data the sensitivity of meson electroproduction to expose the active degrees of freedom underlying resonance transitions as a function of the probed distance scale. For several of the prominent excited states in the lower mass range the short distance behavior is described by a core of three dressed-quarks with running quark mass, and meson-baryon contributions make up significant parts of the excitation strength at large distances. Finally, an outlook is given of baryon resonance physics at the 12 GeV CEBAF electron accelerator.

    ↳ nucl-exhep-exhep-lathep-phEPJ Web Conf.(2017)·6 citations
30. 30*

    O'R Inflation in $F$-term Supergravity

    Sibo Zheng🇨🇳

    The supersymmetric realization of inflation in $F$-term supergravity is usually plagued by the well known "$\eta$" problem. In this paper, a broad class of small-field examples is realized by employing general O' Raifeartaigh superpotentials, where the moduli is identified as the massless inflaton. For illustration we present the simplest example in detail, which can be considered as a generalization of hybrid inflation.

    ↳ astro-ph.COhep-phhep-thNPB(2017)·2 citations
31. 31*

    Excited State Mass spectra and Regge trajectories of Bottom Baryons

    Kaushal Thakkar🇮🇳 · Zalak Shah🇮🇳 · Ajay Kumar Rai🇮🇳 · P. C. Vinodkumar🇮🇳

    We present the mass spectra of radial and orbital excited states of singly heavy bottom baryons; ${\Sigma }_b^{+},{\Sigma }_b^{-},{\Xi }_b^{-},{\Xi }_b^0,{\Lambda }_b^0$ and ${\Omega }_b^{-}$. The QCD motivated hypercentral quark model is employed for the three body description of baryons and the form of confinement potential is hyper coulomb plus linear. The first order correction to the confinement potential is also incorporated in this work. The semi-electronic decay of ${\Omega }_b$ and ${\Xi }_b$ are calculated using the spectroscopic parameters of the baryons. The computed results are compared with other theoretical predictions as well as with the available experimental observations. The Regge trajectories are plotted in (n, $M^2$) plane.

    ↳ nucl-thhep-phNPA(2017)·87 citations
32. 32*

    A Study of the H-dibaryon in Holographic QCD

    Kohei Matsumoto🇯🇵 · Yuya Nakagawa🇯🇵 · Hideo Suganuma (Kyoto U.)🇯🇵

    We study the H-dibaryon (uuddss) in holographic QCD for the first time. Holographic QCD is derived from a QCD-equivalent D-brane system ($S^1$-compactified D4/D8/$\overline{D8}$) in the superstring theory via the gauge/gravity correspondence. In holographic QCD, all baryons appear as topological chiral solitons of Nambu-Goldstone bosons and (axial) vector mesons. In this framework, the H-dibaryon can be described as an SO(3)-type hedgehog state. We present the formalism of the H-dibaryon in holographic QCD, and perform the calculation to investigate its properties in the chiral limit.

    ↳ hep-thhep-phJPS Conf.Proc.(2017)·5 citations
33. 33*

    Black hole and Hawking radiation by type-II Weyl fermions

    G.E. Volovik🇫🇮

    The type-II Weyl and type-II Dirac fermions may emerge behind the event horizon of black holes. Correspondingly the black hole can be simulated by creation of the region with overtilted Weyl or Dirac cones. The filling of the electronic states inside the "black hole" is accompanied by Hawking radiation. The Hawking temperature in the Weyl semimetals can reach the room temperature, if the black hole region is sufficiently small, and thus the effective gravity at the horizon is large.

    ↳ cond-mat.othergr-qchep-phPisma Zh.Eksp.Teor.Fiz.(2016)·109 citations
34. 34*

    Electromagnetic description of three-dimensional time-reversal invariant ponderable topological insulators

    Alberto Martín-Ruiz🇲🇽 · Mauro Cambiaso🇨🇱 · Luis F. Urrutia🇲🇽

    A general technique to analyze the classical interaction between ideal topological insulators, and electromagnetic sources and fields, has been previously elaborated. Nevertheless it is not immediately applicable in the laboratory as it fails to describe real ponderable media. In this work we provide a description of real topologically insulating materials taking into account their dielectric and magnetic properties. For inhomogeneous permittivity and permeability, the problem of finding the Green's function must be solved in an ad hoc manner. Nevertheless, the physically feasible cases of piecewise constant $\epsilon ,\mu$ and $\theta$ make the problem tractable, where $\theta$ encodes the topological magnetoelectric polarizability properties of the medium. To this end we employ the Green's function method to find the fields resulting form the interaction between these materials and electromagnetic sources. Furthermore we exploit the fact that in the cases here studied, the full Green's function can be successfully found if the Green's function of the corresponding ponderable media with $\theta =0$ is known. Our results, satisfactorily reproduce previously existing ones and also generalize some others. The method here elaborated can be exploited to determine the electromagnetic fields for more general configurations aiming to measure the interaction between real 3D topological insulators and electromagnetic fields.

    ↳ cond-mat.str-elhep-phhep-thPRD(2016)·33 citations
35. 35*

    Towards a Gravity Dual for the Large Scale Structure of the Universe

    A. Kehagias🇬🇷 · A. Riotto🇨🇭 · M.S. Sloth🇩🇰

    The dynamics of the large-scale structure of the universe enjoys at all scales, even in the highly non-linear regime, a Lifshitz symmetry during the matter-dominated period. In this paper we propose a general class of six-dimensional spacetimes which could be a gravity dual to the four-dimensional large-scale structure of the universe. In this set-up, the Lifshitz symmetry manifests itself as an isometry in the bulk and our universe is a four-dimensional brane moving in such six-dimensional bulk. After finding the correspondence between the bulk and the brane dynamical Lifshitz exponents, we find the intriguing result that the preferred value of the dynamical Lifshitz exponent of our observed universe, at both linear and non-linear scales, corresponds to a fixed point of the RGE flow of the dynamical Lifshitz exponent in the dual system where the symmetry is enhanced to the Schrodinger group containing a non-relativistic conformal symmetry. We also investigate the RGE flow between fixed points of the Lifshitz dynamical exponent in the bulk and observe that this flow is reflected in a growth rate of the large-scale structure, which seems to be in qualitative agreement with what is observed in current data. Our set-up might provide an interesting new arena for testing the ideas of holography and gravitational duals.

    ↳ hep-thastro-ph.COgr-qchep-phFortsch.Phys.(2016)·1 citation
36. 36*

    Measurement of Elastic pp Scattering at $\sqrt{s}$ = 8 TeV in the Coulomb-Nuclear Interference Region - Determination of the $\rho$-Parameter and the Total Cross-Section

    TOTEM Collaboration: G. Antchev🇨🇿 · P. Aspell🇨🇭 · I. Atanassov🇨🇿 · V. Avati🇵🇱 · J. Baechler🇨🇭 · V. Berardi🇮🇹 · M. Berretti🇨🇭 · E. Bossini🇮🇹 · U. Bottigli🇮🇹 · M. Bozzo🇮🇹 · P. Broulím🇨🇿 · H. Burkhardt🇨🇭 and 77 other authors

    The TOTEM experiment at the CERN LHC has measured elastic proton-proton scattering at the centre-of-mass energy $\sqrt{s}$ = 8 TeV and four-momentum transfers squared, |t|, from 6 x $10^{-4}$ GeV${}^2$ to 0.2 GeV${}^2$. Near the lower end of the |t|-interval the differential cross-section is sensitive to the interference between the hadronic and the electromagnetic scattering amplitudes. This article presents the elastic cross-section measurement and the constraints it imposes on the functional forms of the modulus and phase of the hadronic elastic amplitude. The data exclude the traditional Simplified West and Yennie interference formula that requires a constant phase and a purely exponential modulus of the hadronic amplitude. For parametrisations of the hadronic modulus with second- or third-order polynomials in the exponent, the data are compatible with hadronic phase functions giving either central or peripheral behaviour in the impact parameter picture of elastic scattering. In both cases, the $\rho$-parameter is found to be 0.12 $\pm$ 0.03. The results for the total hadronic cross-section are ${\sigma }_{tot}$ = (102.9 $\pm$ 2.3) mb and (103.0 $\pm$ 2.3) mb for central and peripheral phase formulations, respectively. Both are consistent with previous TOTEM measurements.

    ↳ nucl-exhep-exhep-phEPJC(2016)·181 citations
37. 37*

    Higgs physics at CLIC

    Strahinja Lukić (on behalf of the CLICdp Collaboration)🇷🇸

    The Compact Linear Collider CLIC is an option for a future multi-TeV electron-positron collider, offering the potential for a rich precision physics programme, combined with sensitivity to a wide range of new phenomena. The CLIC physics potential for measurements of the 125 GeV Higgs boson has been studied using full detector simulations for several centre-of-mass energies. The presented results provide crucial input to the energy staging strategy for the CLIC accelerator. The complete physics program for measurements of accessible Higgs boson couplings is presented in this contribution. The ultimate measurement precision is reached when all measurements available at a given centre-of-mass energy are included in combined fits. Operation at a few hundred GeV allows the couplings and width of the Higgs boson to be determined in a model-independent manner through the study of the Higgsstrahlung and WW-fusion processes. At a lepton collider, the measurement of the Higgsstrahlung cross section using the recoil mass technique sets the absolute scale for all Higgs coupling measurements. Recently, it has been shown that including both the leptonic and the hadronic decays of the Z boson in this approach improves the statistical precision significantly. Operation at higher centre-of-mass energies provides large statistics for the study of Higgs boson decays and the potential to directly measure the top Yukawa coupling. At the highest centre-of-mass energy (presently assumed to be 3 TeV), the Higgs boson self-coupling can be determined with 10% precision.

    ↳ hep-exhep-phPoS(2016)·4 citations
38. 38*

    The first moment of azimuthal anisotropy in nuclear collisions from AGS to LHC energies

    Subhash Singha🇺🇸 · Prashanth Shanmuganathan🇺🇸 · Declan Keane🇺🇸

    We review topics related to the first moment of azimuthal anisotropy ($v_1$), commonly known as directed flow, focusing on both charged particles and identified particles from heavy-ion collisions. Beam energies from the highest available, at the CERN LHC, down to projectile kinetic energies per nucleon of a few GeV per nucleon, as studied in experiments at the Brookhaven AGS, fall within our scope. We focus on experimental measurements and on theoretical work where direct comparisons with experiment have been emphasized. The physics addressed or potentially addressed by this review topic includes the study of Quark Gluon Plasma, and more generally, investigation of the Quantum Chromodynamics phase diagram and the equation of state describing the accessible phases.

    ↳ nucl-exhep-exhep-phnucl-thAdv.High Energy Phys.(2016)·40 citations
39. 39*

    Antideuterons in cosmic rays: sources and discovery potential

    Johannes Herms🇩🇪 · Alejandro Ibarra🇩🇪 · Andrea Vittino🇩🇪 · Sebastian Wild🇩🇪

    Antibaryons are produced in our Galaxy in collisions of high energy cosmic rays with the interstellar medium and in old supernova remnants, and possibly, in exotic sources such as primordial black hole evaporation or dark matter annihilations and decays. The search for signals from exotic sources in antiproton data is hampered by large backgrounds from spallation which, within theoretical errors, can solely account for the current data. Due to the higher energy threshold for antideuteron production, which translates into a suppression of the low energy flux from spallations, antideuteron searches have been proposed as a probe for exotic sources. We perform in this paper a comprehensive analysis of the antideuteron fluxes at the Earth expected from known and hypothetical sources in our Galaxy, and we calculate their maximal values consistent with current antiproton data from AMS-02. We find that supernova remnants generate a negligible flux, whereas primordial black hole evaporation and dark matter annihilations or decays may dominate the total flux at low energies. On the other hand, we find that the detection of cosmic antideuterons would require, for the scenarios studied in this paper and assuming optimistic values of the coalescence momentum and solar modulation, an increase of the experimental sensitivity compared to ongoing and planned instruments by at least a factor of 2. Finally, we briefly comment on the prospects for antihelium-3 detection.

    ↳ astro-ph.HEhep-phJCAP(2017)·41 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.