Fri·Jul 17, 2015Friday·July 17, 2015

1. 01*

   Is the CMS eejj excess a hint for light supersymmetry?

   Manuel E. Krauss🇩🇪 · Werner Porod🇩🇪

   We discuss the impact of additional two-body decays of the right-handed neutrino into a light charged Higgs state on the dilepton plus dijet cross sections from resonant $W^{\prime }$ production. We consider in particular a supersymmetric left-right symmetric model which predicts such a light charged Higgs boson. We demonstrate that the $eejj$ excess as measured by CMS can be explained best if the $W^{\prime }$ also has decay modes into Higgsino-like charginos and neutralinos with masses of a few hundred GeV. Provided that this excess is confirmed, the model predicts also one right-handed neutrino with a mass below 200 GeV as well as a doubly charged Higgs boson which should be discovered at the LHC in the near future.

   hep-phPRD(2015)·25 citations
2. 02*

   All-orders worldline holography and higher spins

   Dennis D. Dietrich🇩🇪

   By using the worldline approach to quantum field theory, we demonstrate to all orders that the sources of a quantum field theory over Mink${}_4$ naturally form a field theory over AdS${}_5$. In particular, this holds for higher-spin sources of a free scalar theory. We work entirely within quantum-field theory and do not select a subset of diagrams. As auxiliary fifth dimension Schwinger's proper time is grouped with the physical four spacetime dimensions into an AdS${}_5$ geometry. The four-dimensional sources are extended to five-dimensional fields by a Wilson flow (gradient flow). A variational principle for said flow reproduces the corresponding holographic computation.

   hep-phPRD(2016)·5 citations
3. 03*

   Flavor-Changing Neutral-Current Decays in Top-Specific Variant Axion Model

   Cheng-Wei Chiang🇹🇼 · Hajime Fukuda🇯🇵 · Michihisa Takeuchi🇯🇵 · Tsutomu T. Yanagida🇯🇵

   The invisible variant axion model is very attractive as it is free from the domain wall problem. This model requires two Higgs doublets at the electroweak scale where one Higgs doublet carries a nonzero Peccei-Quinn (PQ) charge and the other is neutral under the PQ $\text{U}(1)$ symmetry. We consider the most interesting and less constrained scenario of the variant axion model, where only the right-handed top quark is charged under the PQ symmetry and couples with the PQ-charged Higgs doublet. As a result, the top quark can decay to the observed standard-model-like Higgs boson $h$ and the charm or up quark, $t\to hc/u$, which is testable soon at the LHC Run-II. Moreover, we propose a method to probe the chiral nature of the Higgs flavor-changing interaction using the angular distribution of $t\to ch$ decays if a sufficient number of such events are observed. We also show that our model has the capacity to explain the $h\to \tau \mu$ decay reported by the CMS Collaboration, if the right-handed tau lepton also carries a PQ charge and couples to the PQ-charged Higgs boson.

   hep-phhep-exJHEP(2015)·42 citations
4. 04*

   Higgs-Gluon Coupling in Warped Extra Dimensional Models with Brane Kinetic Terms

   Ujjal Kumar Dey🇮🇳 · Tirtha Sankar Ray🇮🇳

   Warped models with the Higgs confined to the weak brane and the gauge and matter fields accessing the $Ad{S}_5$ bulk provide viable setting to address the gauge hierarchy problem. Brane kinetic terms for the bulk fields are known to ease some of the tensions of these models with precision electroweak observables and flavor constraints. We study the loop-driven Higgs coupling to the gluons that are relevant to the Higgs program at LHC, in this scenario. We demonstrate a partial cancellation in the contribution of the fermionic Kaluza-Klein (KK) towers within such framework relatively independent of the 5D parameters. The entire dependence of this coupling on the new physics arises from the mixing between the Standard Model states and the KK excitations. We find that the present precision in measurement of these couplings can lead to a constraint on the KK scale up to 1.2 TeV at $95\%$ confidence level.

   hep-phPRD(2016)·7 citations
5. 05*

   General Gauge Mediation at the Weak Scale

   Simon Knapen🇺🇸 · Diego Redigolo🇫🇷 · David Shih🇺🇸

   We completely characterize General Gauge Mediation (GGM) at the weak scale by solving all IR constraints over the full parameter space. This is made possible through a combination of numerical and analytical methods, based on a set of algebraic relations among the IR soft masses derived from the GGM boundary conditions in the UV. We show how tensions between just a few constraints determine the boundaries of the parameter space: electroweak symmetry breaking (EWSB), the Higgs mass, slepton tachyons, and left-handed stop/sbottom tachyons. While these constraints allow the left-handed squarks to be arbitrarily light, they place strong lower bounds on all of the right-handed squarks. Meanwhile, light EW superpartners are generic throughout much of the parameter space. This is especially the case at lower messenger scales, where a positive threshold correction to $m_h$ coming from light Higgsinos and winos is essential in order to satisfy the Higgs mass constraint.

   hep-phJHEP(2016)·18 citations
6. 06*

   Bayesian global analysis of neutrino oscillation data

   Johannes Bergstrom🇪🇸 · M. C. Gonzalez-Garcia🇪🇸 · Michele Maltoni🇪🇸 · Thomas Schwetz🇸🇪

   We perform a Bayesian analysis of current neutrino oscillation data. When estimating the oscillation parameters we find that the results generally agree with those of the ${\chi }^2$ method, with some differences involving $s_{23}^2$ and CP-violating effects. We discuss the additional subtleties caused by the circular nature of the CP-violating phase, and how it is possible to obtain correlation coefficients with $s_{23}^2$. When performing model comparison, we find that there is no significant evidence for any mass ordering, any octant of $s_{23}^2$ or a deviation from maximal mixing, nor the presence of CP-violation.

   hep-phJHEP(2015)·65 citations
7. 07*

   Nonuniversal gaugino masses in a magnetized toroidal compactification of SYM theories

   Keigo Sumita🇯🇵

   This paper proposes a concrete model of nonuniversal gaugino masses on the basis of higher-dimensional supersymmetric Yang-Mills theories compactified on a magnetized factorizable torus, and we estimate the gauge coupling constants and gaugino masses in the model. In the magnetized toroidal compactifications, the four-dimensional effective action can be obtained analytically identifying its dependence on moduli fields, where the magnetic fluxes are able to yield the flavor structure of the minimal supersymmetric standard model (MSSM). The obtained gauge kinetic functions contains multi moduli fields and their dependence is nonuniversal for the three gauge fields. The nonuniversal gauge kinetic functions can lead to nonuniversal gaugino masses at a certain high energy scale (e.g. compactification scale). Our numerical analysis of them shows that, particular ratios of gaugino masses, which were found to enhance the Higgs boson mass and lead to "natural supersymmetry" in the MSSM, can be realized in our model, while the gauge couplings are unified as is achieved in the MSSM.

   hep-phhep-thJHEP(2015)·5 citations
8. 08*

   Shadowing Effects on $J/\psi$ and ${\rm Y}$ Production at the LHC

   R. Vogt🇺🇸

   Background: Proton-nucleus collisions have been used as a intermediate baseline for the determination of cold medium effects. They lie between proton-proton collisions in vacuum and nucleus-nucleus collisions which are expected to be dominated by hot matter effects. Modifications of the quark densities in nuclei relative to those of the proton are well established although those of the gluons in the nucleus are not well understood. We focus on the effect of these on quarkonium production in proton-lead collisions at the LHC at a center of mass energy of 5.02 TeV.

   hep-phPRC(2015)·68 citations
9. 09*

   On the physical DGLAP evolution of structure functions and its dependence on the renormalization scale

   M. Hentschinski🇲🇽

   Physical anomalous dimensions are a formulation of the DGLAP evolution of Deep Inelastic structure functions which is independent of factorization scheme and -scale. In this proceedings we provide an outlook on possible applications, in particular in the search of saturation effects. As an original contribution we present a short study of the renormalization scale dependence of physical evolved structure functions for large initial scale $Q_0^2=30$GeV${}^2$

   hep-phPoS(2015)·0 citations
10. 10*

    2 TeV Higgs boson and diboson excess at the LHC

    Chuan-Hung Chen🇹🇼 · Takaaki Nomura🇹🇼

    Diboson resonance with mass around 2 TeV in the dijet invariant mass spectrum is reported by ATLAS experiment in proton-proton collisions at $\sqrt{s}=8$ TeV. We propose that the candidate of resonance is a heavy neutral Higgs $H^0$ or charged Higgs $H^{\pm }$ and use the extended two-Higgs-doublet (THD) to demonstrate the potentiality. We find that the large Yukawa coupling to the first generation of quarks can be realized in THD and the required value for producing the right resonance production cross section is of $\mathcal{O}(0.06-0.2)$. Besides $WW/ZZ$ channels, we find that if the mass of pseudoscalar $A^0$ satisfies the jet mass tagging condition $|m_j-m_{Z/W}|<13$ GeV, the diboson excess could be also caused by $Z{A}^0$ or $W{A}^0$ channel.

    hep-phhep-exPLB(2015)·35 citations
11. 11*

    Possible large $CP$ violation in three body decays of heavy baryon

    Zhen-Hua Zhang🇨🇳 · Chao Wang🇨🇳 · Xin-Heng Guo🇨🇳

    We propose a new mechanism which can introduce large $CP$ asymmetries in the phase spaces of three-body decays of heavy baryons. In this mechanism, a large $CP$ asymmetry is induced by the interference of two intermediate resonances, which subsequently decay into two different combinations of final particles. We apply this mechanism to the decay channel ${\Lambda }_b^0\to p{\pi }^0{\pi }^{-}$, and find that the differential $CP$ asymmetry can reach as large as $50\%$, while the regional $CP$ asymmetry can reach as large as $16\%$ in the interference region of the phase space.

    hep-phPLB(2015)·2 citations
12. 12*

    Pure Gravity Mediation and Spontaneous B-L Breaking from Strong Dynamics

    Kaladi S. Babu🇺🇸 · Kai Schmitz🇯🇵 · Tsutomu T. Yanagida🇯🇵

    In pure gravity mediation (PGM), the most minimal scheme for the mediation of supersymmetry (SUSY) breaking to the visible sector, soft masses for the standard model gauginos are generated at one loop rather than via direct couplings to the SUSY-breaking field. In any concrete implementation of PGM, the SUSY-breaking field is therefore required to carry nonzero charge under some global or local symmetry. As we point out in this note, a prime candidate for such a symmetry might be B-L, the Abelian gauge symmetry associated with the difference between baryon number B and lepton number L. The F-term of the SUSY-breaking field then not only breaks SUSY, but also B-L, which relates the respective spontaneous breaking of SUSY and B-L at a fundamental level. As a particularly interesting consequence, we find that the heavy Majorana neutrino mass scale ends up being tied to the gravitino mass, Lambda_N ~ m_3/2. Assuming nonthermal leptogenesis to be responsible for the generation of the baryon asymmetry of the universe, this connection may then explain why SUSY necessarily needs to be broken at a rather high energy scale, so that m_3/2 >~ 1000 TeV in accord with the concept of PGM. We illustrate our idea by means of a minimal model of dynamical SUSY breaking, in which B-L is identified as a weakly gauged flavor symmetry. We also discuss the effect of the B-L gauge dynamics on the superparticle mass spectrum as well as the resulting constraints on the parameter space of our model. In particular, we comment on the role of the B-L D-term.

    hep-phhep-thNPB(2016)·5 citations
13. 13*

    Reduction of couplings in the MSSM

    George Tsamis (National Technical University of Athens, Physics Department)🇬🇷

    We present an application of the reduction of couplings program in the minimal supersymmetric Standard Model (MSSM). We investigate if a functional relation between ${\alpha }_1$ and ${\alpha }_2$ gauge couplings can be realized which is Renormalization Group Invariant (RGI). Following the same procedure for the top and bottom Yukawa couplings we end up with a prediction of a narrow window for tan$\beta$, which is one of the basic parameters that determine the light Higgs mass.

    hep-phPoS(2015)·1 citation
14. 14*

    Role of pentaquark components in $\varphi$ meson production proton-antiproton annihilation reactions

    S. Srisuphaphon🇹🇭 · A. Kaewsnod🇹🇭 · A. Limphirat🇹🇭 · K. Khosonthongkee🇹🇭 · Y. Yan🇹🇭

    The pentaquark component is included in the proton wave functions to study phi meson production proton-antiproton annihilation reactions. With all possible configurations of the uuds subsystem proposed for describing the strangeness spin and magnetic moment of the proton, we estimate the branching ratios of the annihilation reactions at rest proton-antiproton to phi + X (X=pi, eta, rho, omega) from atomic proton-antiproton S- and P-wave states by using effective quark line diagrams incorporating the 3P0 model. The best agreement of theoretical prediction with the experimental data is found when the pentaquark configuration of the proton wave function takes the flavor-spin symmetry, [4]_FS [22]_F [22]_S.

    hep-phPRC(2016)·4 citations
15. 15*

    Form factors of the isovector scalar current and the $\eta \pi$ scattering phase shifts

    M. Albaladejo🇪🇸 · B. Moussallam🇫🇷

    A model for S-wave $\eta \pi$ scattering is proposed which could be realistic in an energy range from threshold up to above one GeV, where inelasticity is dominated by the $K\bar{K}$ channel. The $T$-matrix, satisfying two-channel unitarity, is given in a form which matches the chiral expansion results at order $p^4$ exactly for the $\eta \pi \to \eta \pi$, $\eta \pi \to K\bar{K}$ amplitudes and approximately for $K\bar{K}\to K\bar{K}$. It contains six phenomenological parameters. Asymptotic conditions are imposed which ensure a minimal solution of the Muskhelishvili-Omnès problem, thus allowing to compute the $\eta \pi$ and $K\bar{K}$ form factor matrix elements of the $I=1$ scalar current from the $T$-matrix. The phenomenological parameters are determined such as to reproduce the experimental properties of the $a_0(980)$, $a_0(1450)$ resonances, as well as the chiral results of the $\eta \pi$ and $K\bar{K}$ scalar radii which are predicted to be remarkably small at $O(p^4)$. This $T$-matrix model could be used for a unified treatment of the $\eta \pi$ final-state interaction problem in processes such as ${\eta }^{\prime }\to \eta \pi \pi$, $\varphi \to \eta \pi \gamma$, or the $\eta \pi$ initial-state interaction in $\eta \to 3\pi$.

    hep-phEPJC(2015)·60 citations
16. 16*

    Strange baryon spectroscopy in the relativistic quark model

    R. N. Faustov🇷🇺 · V. O. Galkin🇷🇺

    Mass spectra of strange baryons are calculated in the framework of the relativistic quark model based on the quasipotential approach. Baryons are treated as the relativistic quark-diquark bound systems. It is assumed that two quarks with equal constituent masses form a diquark. The diquark excitations and its internal structure are consistently taken into account. Calculations are performed up to rather high orbital and radial excitations of strange baryons. On this basis the Regge trajectories are constructed. The obtained results are compared with available experimental data and previous predictions. It is found that all masses of the 4- and 3-star, as well as most of the 2- and 1-star states of strange baryons with established quantum numbers are well reproduced. The developed relativistic quark-diquark model predicts less excited states than three-quark models of strange baryons.

    hep-phhep-exPRD(2015)·92 citations
17. 17*

    Dwarf Galaxy $\gamma$-excess and 3.55 keV X-ray Line In A Nonthermal Dark Matter Model

    Anirban Biswas🇮🇳 · Debasish Majumdar🇮🇳 · Probir Roy🇮🇳

    Recent data from Reticulum II (RetII) require the energy range of the FermiLAT $\gamma$-excess to be $\sim$ $2-10$ GeV. We adjust our unified nonthermal Dark Matter (DM) model to accommodate this. We have two extra scalars beyond the Standard Model to also explain 3.55 keV X-ray line. Now the mass of the heavier of them has to be increased to lie around 250 GeV, while that of the lighter one remains at 7.1 keV. This requires a new seed mechanism for the $\gamma$-excess and new Boltzmann equations for the generation of the DM relic density. All concerned data for RetII and the X-ray line can now be fitted well and consistency with other indirect limits attained.

    hep-phEPL(2016)·6 citations
18. 18*

    Inverse-square law violation and reactor antineutrino anomaly

    D.V. Naumov🇷🇺 · V.A. Naumov🇷🇺 · D.S. Shkirmanov🇷🇺

    We discuss a possibility that the so-called reactor antineutrino anomaly can be, at least in part, explained by applying a quantum field-theoretical approach to neutrino oscillations, which in particular predicts a small deviation from the classical inverse-square law at short but macroscopic distances between the neutrino source and detector. An extensive statistical analysis of the reactor data is performed to examine this speculation.

    hep-phhep-exnucl-exphysics.data-anPhys.Part.Nucl.(2017)·11 citations
19. 19*

    The ${\Lambda }_b\to J/\psi K\Xi$ decay and the higher order chiral terms of the meson baryon interaction

    A. Feijoo🇪🇸 · V.K. Magas🇪🇸 · A. Ramos🇪🇸 · E. Oset🇪🇸

    We study the weak decay of the ${\Lambda }_b$ into $J/\psi K\Xi$ and $J/\psi \eta \Lambda$ states, and relate these processes to the ${\Lambda }_b\to J/\psi \bar{K}N$ decay mode. The elementary weak transition at the quark level proceeds via the creation of a $J/\psi$ meson and an excited $sud$ system with $I=0$, which upon hadronization leads to $\bar{K}N$ or $\eta \Lambda$ pairs. These states undergo final state interaction in coupled channels and produce a final meson-baryon pair. The $K\Xi$ state only occurs via rescattering, hence making the ${\Lambda }_b\to J/\psi K\Xi$ process very sensitive to the details of the meson-baryon interaction in strangeness $S=-1$ and isospin $I=0$. We show that the corresponding invariant mass distribution is dominated by the next-to-leading order terms of the chiral interaction. The $I=0$ selectivity of this decay, and its large sensitivity to the higher order terms, makes its measurement very useful and complementary to the $K^{-}p\to K\Xi$ cross section data. The rates of the ${\Lambda }_b\to J/\psi K\Xi$ and ${\Lambda }_b\to J/\psi \eta \Lambda$ invariant mass distributions are sizable compared to those of the ${\Lambda }_b\to J/\psi \bar{K}N$ decay, which is measured experimentally, thus, we provide arguments for an experimental determination of these decay modes that will help us understand better the chiral dynamics at higher energies.

    hep-phnucl-thPRD(2015)·44 citations
20. 20*

    Comparing Galactic Center MSSM dark matter solutions to the Reticulum II gamma-ray data

    Abraham Achterberg🇳🇱 · Melissa van Beekveld🇳🇱 · Wim Beenakker🇳🇱 · Sascha Caron🇳🇱 · Luc Hendriks🇳🇱

    Observations with the Fermi Large Area Telescope (LAT) indicate a possible small photon signal originating from the dwarf galaxy Reticulum II that exceeds the expected background between 2 GeV and 10 GeV. We have investigated two specific scenarios for annihilating WIMP dark matter within the phenomenological Minimal Supersymmetric Standard Model (pMSSM) framework as a possible source for these photons. We find that the same parameter ranges in pMSSM as reported by an earlier paper to be consistent with the Galactic center excess, is also consistent with the excess observed in Reticulum II, resulting in a J-factor of ${\log }_{10}(J({\alpha }_{int}=0.5deg))\simeq (20.3-20.5{)}_{-0.3}^{+0.2}$. This J-factor is consistent with ${\log }_{10}(J({\alpha }_{int}=0.5deg))=19.5_{-0.6}^{+1.0}$ GeV${}^2$cm${}^{-5}$, which is derived using an optimized spherical Jeans analysis of kinematic data obtained from the Michigan/Magellan Fiber System (M2FS).

    hep-phJCAP(2015)·12 citations
21. 21*

    Reheating with a Composite Higgs

    Djuna Croon🇬🇧 · Veronica Sanz🇬🇧 · Ewan R. M. Tarrant🇬🇧

    The flatness of the inflaton potential and lightness of the Higgs could have the common origin of the breaking of a global symmetry. This scenario provides a unified framework of Goldstone Inflation and Composite Higgs, where the inflaton and the Higgs both have a pseudo--Goldstone boson nature. The inflaton reheats the Universe via decays to the Higgs and subsequent secondary production of other SM particles via the top and massive vector bosons. We find that inflationary predictions and perturbative reheating conditions are consistent with CMB data for sub--Planckian values of the fields, as well as opening up the possibility of inflation at the TeV scale. We explore this exciting possibility, leading to an interplay between collider data and cosmological constraints.

    hep-phastro-ph.COPRD(2016)·21 citations
22. 22*

    Heavy baryons in the large Nc limit

    C. Albertus🇪🇸 · E. Ruiz Arriola🇪🇸 · I. P. Fernando🇺🇸 · J. L. Goity🇺🇸

    It is shown that in the large Nc limit heavy baryon masses can be estimated quantitatively in a 1/Nc expansion using the Hartree approximation. The results are compared with available lattice calculations for different values of the ratio between the square root of the string tension and the heavy quark mass tension independent of Nc. Using a potential adjusted to agree with the one obtained in lattice QCD, a variational analysis of the ground state spin averaged baryon mass is performed using Gaussian Hartree wave functions. Relativistic corrections through the quark kinetic energy are included. The results provide good estimates for the first sub-leading in 1/Nc corrections.

    hep-phnucl-thPLB(2015)·2 citations
23. 23*

    Axion-like particle dark matter in the linear regime of structure formation

    Qiaoli Yang🇨🇳 · Haoran Di🇨🇳

    If axion-like particles (ALPs) constitute a major part of dark matter (DM), due to the bosonic nature and a relative small mass, they could behave differently from the point like dark matter particles on the formation of the cosmic structures. When studying the structure formation, it is often useful to consider DM as a special fluid with a given density and a given velocity. ALP fluid obeys a same continuity equation comparing to the point-like collisionless DM but has a different first-order velocity equation. In the linear regime of structure formation, the resulted observational differences are negligible for the QCD axions but can be interesting for very light ALPs.

    hep-phastro-ph.COhep-thInt.J.Mod.Phys.A(2017)·3 citations
24. 24*

    Reinterpretation of the Starobinsky model

    Takehiko Asaka🇯🇵 · Satoshi Iso🇯🇵 · Hikaru Kawai🇯🇵 · Kazunori Kohri🇯🇵 · Toshifumi Noumi🇯🇵 · Takahiro Terada🇰🇷

    The Starobinsky model of inflation, consistent with Planck 2015, has a peculiar form of the action, which contains the leading Einstein term $R$, the $R^2$ term with a huge coefficient, and negligible higher-order terms. We propose an explanation of this form based on compactification of extra dimensions. Once tuning of order $10^{-4}$ is accepted to suppress the linear term $R$, we no longer have to suppress higher-oder terms, which give nontrivial corrections to the Starobinsky model. We show our predictions of the spectral index, its runnings, and the tensor-to-scalar ratio. Finally, we discuss a possibility that quantum gravity may appear at the scale $\Lambda \gtrsim 5\times 10^{15}$ GeV.

    ↳ hep-thastro-ph.COgr-qchep-phPTEP(2016)·47 citations
25. 25*

    Evidence for dark matter interactions in cosmological precision data?

    Julien Lesgourgues🇩🇪 · Gustavo Marques-Tavares🇺🇸 · Martin Schmaltz🇺🇸

    We study a two-parameter extension of the cosmological standard model $\Lambda$CDM in which cold dark matter interacts with a new form of dark radiation. The two parameters correspond to the energy density in the dark radiation fluid $\Delta N_{\mathrm{fluid}}$ and the interaction strength between dark matter and dark radiation. The interactions give rise to a very weak "dark matter drag" which damps the growth of matter density perturbations throughout radiation domination, allowing to reconcile the tension between predictions of large scale structure from the CMB and direct measurements of ${\sigma }_8$. We perform a precision fit to Planck CMB data, BAO, large scale structure, and direct measurements of the expansion rate of the universe today. Our model lowers the $\chi$-squared relative to $\Lambda$CDM by about 12, corresponding to a preference for non-zero dark matter drag by more than $3\sigma$. Particle physics models which naturally produce a dark matter drag of the required form include the recently proposed non-Abelian dark matter model in which the dark radiation corresponds to massless dark gluons.

    ↳ astro-ph.COhep-phJCAP(2016)·193 citations
26. 26*

    Polarized Lepton-Nucleon Elastic Scattering and a Search for a Light Scalar Boson

    Yu-Sheng Liu🇺🇸 · Gerald A. Miller🇺🇸

    Lepton-nucleon elastic scattering, using the one-photon and one-scalar-boson exchange mechanisms considering all possible polarizations, is used to study searches for a new scalar boson and suggest new measurements of the nucleon form factors. A new light scalar boson, which feebly couples to leptons and nucleons, may account for the proton radius and muon $g-2$ puzzles. We show that the scalar boson produces relatively large effects in certain kinematic region when using sufficient control of lepton and nucleon spin polarization. We generalize current techniques to measure the ratio $G_E/G_M$ and present a new method to separately measure $G_M^2$ and $G_E^2$ using polarized incoming and outgoing muons.

    ↳ nucl-thhep-phnucl-exPRC(2015)·12 citations
27. 27*

    Net baryon number fluctuations across the chiral phase transition at finite density in the strong coupling lattice QCD

    Terukazu Ichihara🇯🇵 · Kenji Morita🇯🇵 · Akira Ohnishi🇯🇵

    We investigate the net-baryon number fluctuations across the chiral phase transition at finite density in the strong coupling and chiral limit. Mesonic field fluctuations are taken into account by using the auxiliary field Monte-Carlo method. We find that the higher-order cumulant ratios, $S\sigma$ and $\kappa {\sigma }^2$, show oscillatory behavior around the phase boundary at $\mu /T\gtrsim 0.2$, and there exists the region where the higher-order cumulant ratios are negative. The negative region of $\kappa {\sigma }^2$ is found to shrink with increasing lattice size. This behavior agrees with the expectations from the scaling analysis.

    ↳ hep-lathep-phnucl-thPTEP(2015)·14 citations
28. 28*

    Femto-cyclones and hyperon polarization in Heavy-Ion Collisions

    M.I. Baznat🇷🇺 · K.K. Gudima🇲🇩 · A.S. Sorin🇷🇺 · O.V. Teryaev🇷🇺

    We study the structure of vorticity and hydrodynamic helicity fields in peripheral heavy-ion collisions using the kinetic Quark-Gluon String Model. The angular momentum conservation within this model holds with a good accuracy. We observe the formation of specific toroidal structures of vorticity field (vortex sheets). Their existence is mirrored in the polarization of hyperons of the percent order.

    ↳ nucl-thhep-phnucl-exPRC(2016)·67 citations
29. 29*

    Proton gaps and cooling of neutron stars with a stiff hadronic EoS

    Hovik Grigorian🇷🇺 · Dmitry N. Voskresensky🇷🇺 · David Blaschke🇷🇺

    The recent measurements of the masses of the pulsar J00737-3039B and of the companion J1756-2251 and pulsars PSR J1614-2230, PSR J0348-0432 demonstrate the existence of compact stars with masses in a broad range from 1.2 to 2 $M_{\odot }$. To fulfill the constraint $M_{\max }>2M_{\odot }$ and to demonstrate the possibility of cooling scenarios for purely hadronic and further for hybrid stars we exploit the stiff DD2 hadronic equation of state producing a maximum neutron star mass $M\simeq 2.43M_{\odot }$. We show that the "nuclear medium cooling" scenario for neutron stars comfortably explains the whole set of cooling curves just by a variation of the star masses without the necessity for the occurrence of the direct Urca reaction. To describe the cooling data with the very stiff DD2 equation of state we select a proton gap profile from those exploited in the literature and allow for a variation of the effective pion gap controlling the efficiency of the medium modified Urca process. Fast cooling of young neutron stars like it is seen in the data for Cas A is explained with the DD2 equation of state when the following conditions are provided: the presence of an efficient medium modified Urca process, and a large proton gap at densities $n\le 2n_0$ vanishing for $n\ge (2.5-3)n_0$, where $n_0$ is the saturation nuclear density.

    ↳ astro-ph.HEhep-phnucl-th1 citation

* 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.