Wed·Mar 8, 2017Wednesday·March 8, 2017

1. 01*

   Maximum Entropy Inferences on the Axion Mass in Models with Axion-Neutrino Interaction

   Alexandre Alves🇧🇷 · Alex G. Dias🇧🇷 · Roberto da Silva🇧🇷

   In this work we use the Maximum Entropy Principle (MEP) to infer the mass of an axion which interacts to photons and neutrinos in an effective low energy theory. The Shannon entropy function to be maximized is suitably defined in terms of the axion branching ratios. We show that MEP strongly constrains the axion mass taking into account the current experimental bounds on the neutrinos masses. Assuming that the axion is massive enough to decay into all the three neutrinos and that MEP fixes all the free parameters of the model, the inferred axion mass is in the interval $0.1$eV$<m_A<0.2$ eV, which can be tested by forthcoming experiments such as IAXO. However, even in the case where MEP fixes just the axion mass and no other parameter, we found that $0.1$ eV $<m_A<6.3$ eV in the DFSZ model with right-handed neutrinos. Moreover, a light axion, allowed to decay to photons and the lightest neutrino only, is determined by MEP as a viable dark matter candidate.

   hep-phcond-mat.stat-mechhep-thphysics.data-anBraz.J.Phys.(2017)·31 citations
2. 02*

   Distinguishing A Higgs-Like Dilaton Scenario With A Complete Bosonic Effective Field Theory Basis

   P. Hernandez-Leon🇪🇸 · L. Merlo🇪🇸

   A Higgs-like dilaton owns couplings that differ from those of the Standard Model Higgs and of a generic Composite Higgs. The complete bosonic basis for a Higgs-like dilaton is presented at the first subleading order. A comparison with the Standard Model, the Standard Model Effective Field Theory and the generic Lagrangian for the minimal $SO(5)/SO(4)$ Composite Higgs model is performed. Observables that can disentangle the different hypotheses are identified.

   hep-phPRD(2017)·38 citations
3. 03*

   Exact RG Invariance and Symmetry Improved 2PI Effective Potential

   Apostolos Pilaftsis🇬🇧 · Daniele Teresi🇧🇪

   The Symmetry Improved Two-Particle-Irreducible (SI2PI) formalism is a powerful tool to calculate the effective potential beyond perturbation theory, whereby infinite sets of selective loop-graph topologies can be resummed in a systematic and consistent manner. In this paper we study the Renormalization-Group (RG) properties of this formalism, by proving for the first time a number of new field-theoretic results. First, the RG runnings of all proper 2PI couplings are found to be UV finite, in the Hartree-Fock and sunset approximations of the 2PI effective action. Second, the SI2PI effective potential is exactly RG invariant, in contrast to what happens in the ordinary One-Particle-Irreducible (1PI) perturbation theory, where the effective potential is RG invariant only up to higher orders. Finally, we show how the effective potential of an O(2) theory evaluated in the SI2PI framework, appropriately RG improved, can reach a higher level of accuracy, even up to one order of magnitude, with respect to the corresponding one obtained in the 1PI formalism.

   hep-phhep-thNPB(2017)·20 citations
4. 04*

   Gluon Tomography from Deeply Virtual Compton Scattering at Small-x

   Yoshitaka Hatta🇯🇵 · Bo-Wen Xiao🇨🇳 · Feng Yuan🇺🇸

   We present a full evaluation of the deeply virtual Compton scattering (DVCS) cross section in the dipole framework in the small-x region. The result features the $\cos \varphi$ and $\cos 2\varphi$ azimuthal angular correlations which have been missing in previous studies based on the dipole model. In particular, the $\cos 2\varphi$ term is generated by the elliptic gluon Wigner distribution whose measurement at the planned electron-ion collider (EIC) provides an important information about the gluon tomography at small-x. We also show the consistency with the standard collinear factorization approach based on the quark and gluon generalized parton distributions (GPDs).

   hep-phPRD(2017)·96 citations
5. 05*

   Supersymmetric D-term Twin Higgs

   Marcin Badziak🇵🇱 · Keisuke Harigaya🇺🇸

   We propose a new type of supersymmetric Twin Higgs model where the SU(4) invariant quartic term is provided by a D-term potential of a new U(1) gauge symmetry. In the model the 125 GeV Higgs mass can be obtained for stop masses below 1 TeV, and a tuning required to obtain the correct electroweak scale can be as low as 20 %. A stop mass of about 2 TeV is also possible with tuning of order O(10) %.

   hep-phJHEP(2017)·47 citations
6. 06*

   Magnetic-induced condensate, vortices and vortons in color-flavor-locked-type matter

   Fu-Ping Peng🇨🇳 · Xiao-Bing Zhang🇨🇳 · Yi Zhang🇨🇳

   By considering Higgs modes within the Ginzburg-Landau framework, we study influences of a rotated magnetic field on the color-flavor-locked-type matter of dense QCD. We demonstrate, in a model-independent way, that a diquark condensate may be triggered by the magnetic response of rotated-charged Higgs modes, in addition to the known color-flavor-locked condensate. Moreover, the condensate is applied to explore formations of vortices in the presence of external magnetic fields. The superfluid-like vortices are constructed for the magnetic-induced condensate. In the situation including both kinds of condensates, the theoretical possibility of vortons is suggested and the formation condition and the energy stability are investigated semi-classically.

   hep-ph0 citations
7. 07*

   Cosmological Production of Electroweak Monopole

   Y. M. Cho🇰🇷 · Kyoungtae Kimm🇰🇷 · Seunghun Oh🇰🇷 · J. H. Yoon🇰🇷

   We discuss the cosmological production and the successive evolution of the electroweak (Cho-Maison) monopole in the standard model, and estimate the remnant monopole density at present universe. We confirm that, although the electroweak phase transition is of the first order, it is very mildly the first order. So the monopole production comes from the thermal fluctuations of the Higgs field after the phase transition, not the vacuum bubble collisions during the phase transition. Moreover, while the monopoles are produced copiously around the Ginzburg temperature $T_G\simeq 59.6\mathrm{TeV}$, most of them are annihilated as soon as created. This annihilation process continues very long time, untill the monopoles are decoupled from the other matters when the temperature cools to about 30 MeV. As the result the remnant monopole density at present universe becomes very small, of $10^{-11}$ of the critical density, too small to affect the standard cosmology and too small be the dark matter. We discuss the physical implications of our results on the ongoing monopole detection experiments, in particular on MoEDAL, IceCube, ANTARES, Auger, and Super-Kamiokande.

   hep-phEPJ Web Conf.(2018)·2 citations
8. 08*

   QCD mechanisms for accessing the nucleon GPDs with the exclusive pion-induced Drell-Yan process at J-PARC

   Kazuhiro Tanaka (Juntendo Univ.)🇯🇵

   Generalized parton distributions (GPDs) encoding multidimensional information of hadron partonic structure appear as the building blocks in a factorized description of hard exclusive reactions. The nucleon GPDs have been accessed by deeply virtual Compton scattering and deeply virtual meson production with lepton beam. A complementary probe with hadron beam is the exclusive pion-induced Drell-Yan process. We discuss recent theoretical advances on describing this process in terms of the partonic subprocess convoluted with the nucleon GPDs and the pion distribution amplitudes. Furthermore, we mention the feasibility study for measuring the exclusive pion-induced Drell-Yan process, ${\pi }^{-}p\to {\mu }^{+}{\mu }^{-}n$, via a spectrometer at the High Momentum Beamline being constructed at J-PARC in Japan. We also point out the possible soft partonic mechanisms beyond the QCD factorization framework, which could give important contributions at J-PARC kinematics, and present an estimate of the soft mechanisms making use of dispersion relations and quark-hadron duality. Realization of the measurement of the exclusive pion-induced Drell-Yan process at J-PARC will provide a new test of QCD descriptions of a novel class of hard exclusive reactions. It will also offer the possibility of experimentally accessing nucleon GPDs at large timelike virtuality.

   hep-phhep-exnucl-exnucl-th3 citations
9. 09*

   Lepton flavor violating Higgs Boson Decays in Supersymmetric High Scale Seesaw Models

   M.E. Gomez🇪🇸 · S. Heinemeyer🇪🇸 · M. Rehman🇪🇸

   Within the MSSM, we have evaluated the decay rates for the lepton flavour violating Higgs boson decays (LFVHD) $h\to l_i{l}_j$ where $l_{i,j}$ are charged leptons and $i\ne j$. This has been done in a model independent (MI) way as well as in supersymmetric high scale seesaw models, in particular Type I see-saw model. Lepton flavour violation (LFV) is generated by non-diagonal entries in the mass matrix of the sleptons. In a first step we use the model independent approach where LFV (off-diagonal entries in the mass matrix) is introduced by hand while respecting the direct search constraints from the charged lepton flavor violating (cLFV) processes. In the second step we use high scale see-saw models where LFV is generated via renormalization group equations (RGE) from the grand unification scale (GUT) down to electroweak scale. cLFV decays are the most restrictive ones and exclude a large part of the parameter space for the MI as well as the high scale see-saw scenarios. Due to very strict constraints from cLFV, it is difficult to find large corrections to LFVHD. This applies in particular to $h\to \tau \mu$ where hints of an excess have been observed. If this signal is confirmed, it could not be explained with the models under investigation.

   hep-phJ.Part.Phys.(2017)·15 citations
10. 10*

    Correlations and fluctuations of the gauge topology at finite temperatures

    Rasmus Larsen🇺🇸 · Edward Shuryak🇺🇸

    Instanton-dyons are topological solitons -- solutions of Yang-Mills equations -- which appear at non-trivial expectation value of $A_0$ at nonzero temperatures. Using the ensembles of those, generated in our previous work, for 2-color and 2-flavor QCD, below and above the deconfinement-chiral phase transition, we study the correlations between them, as well as fluctuations of several global charges in the sub-volumes of the total volume. The determined correlation lengths are the finite-$T$ extension of hadronic masses, such as that of ${\eta }^{\prime }$ meson.

    hep-phhep-latnucl-th2 citations
11. 11*

    Higher-twist B-meson Distribution Amplitudes in HQET

    V. M. Braun🇩🇪 · Yao Ji🇩🇪 · A. N. Manashov🇩🇪

    We present a systematic study of higher-twist distribution amplitudes (DAs) of the B-meson which give rise to power-suppressed $1/m_B$ contributions to B-decays in final states with energetic light particles in the framework of QCD factorization. As the main result, we find that the renormalization group equations for the three-particle distributions are completely integrable in the large $N_c$ limit and can be solved exactly. General properties of the solutions are studied. We propose simple models for higher-twist DAs which satify all existing constraints and can be used in phenomenological studies.

    hep-phJHEP(2017)·99 citations
12. 12*

    Long Lived Light Scalars as Probe of Low Scale Seesaw Models

    P. S. Bhupal Dev🇺🇸 · Rabindra N. Mohapatra🇺🇸 · Yongchao Zhang🇧🇪

    We point out that in generic TeV scale seesaw models for neutrino masses with local $B-L$ symmetry breaking, there is a phenomenologically allowed range of parameters where the Higgs field responsible for $B-L$ symmetry breaking leaves a physical real scalar field with mass around GeV scale. This particle (denoted here by $H_3$) is weakly mixed with the Standard Model Higgs field ($h$) with mixing ${\theta }_1\lesssim m_{H_3}/m_h$, barring fine-tuned cancellation. In the specific case when the $B-L$ symmetry is embedded into the TeV scale left-right seesaw scenario, we show that the bounds on the $h-H_3$ mixing ${\theta }_1$ become further strengthened due to low energy flavor constraints, thus forcing the light $H_3$ to be long lived, with displaced vertex signals at the LHC. The property of left-right TeV scale seesaw models are such that they make the $H_3$ decay to two photons as the dominant mode. This is in contrast with a generic light scalar that mixes with the SM Higgs boson, which could also have leptonic and hadronic decay modes with comparable or larger strength. We discuss the production of this new scalar field at the LHC and show that it leads to testable displaced vertex signals of collimated photon jets, which is a new distinguishing feature of the left-right seesaw model. We also study a simpler version of the model where the $SU(2{)}_R$ breaking scale is much higher than the $\mathcal{O}$(TeV) $U(1{)}_{B-L}$ breaking scale, in which case the production and decay of $H_3$ proceed differently, but its long lifetime feature is still preserved for a large range of parameters. Thus, the search for such long-lived light scalar particles provides a new way to probe TeV scale seesaw models for neutrino masses at colliders.

    hep-phhep-exNPB(2017)·86 citations
13. 13*

    Kinetic description of Bose-Einstein condensation with test particle simulations

    Kai Zhou🇩🇪 · Zhe Xu🇨🇳 · Pengfei Zhuang🇨🇳 · Carsten Greiner🇩🇪

    We present a kinetic description of Bose-Einstein condensation for particle systems being out of thermal equilibrium, which may happen for gluons produced in the early stage of ultra-relativistic heavy-ion collisions. The dynamics of bosons towards equilibrium is described by a Boltzmann equation including Bose factors. To solve the Boltzmann equation with the presence of a Bose-Einstein condensate we make further developments of the kinetic transport model BAMPS (Boltzmann Approach of MultiParton Scatterings). In this work we demonstrate the correct numerical implementations by comparing the final numerical results to the expected solutions at thermal equilibrium for systems with and without the presence of Bose-Einstein condensate. In addition, the onset of the condensation in an over-populated gluon system is studied in more details. We find that both expected power-law scalings denoted by the particle and energy cascade are observed in the calculated gluon distribution function at infrared and intermediate momentum regions, respectively. Also, the time evolution of the hard scale exhibits a power-law scaling in a time window, which indicates that the distribution function is approximately self-similar during that time.

    hep-phnucl-thPRD(2017)·14 citations
14. 14*

    Partial waves in $B_s^{\ast }{\bar{B}}_s^{\ast }$ production in $e^{+}{e}^{-}$ annihilation near threshold

    M.B. Voloshin🇺🇸

    The production of the vector meson pairs $B_s^{\ast }{\bar{B}}_s^{\ast }$ in the $e^{+}{e}^{-}$ annihilation is generally contributed by two $P$ wave amplitudes with different total spin $S$ of the mesons, $S=0$ and $S=2$, and also by an $F$ wave amplitude. Belle has recently reported a study of the available data at the energy of the ${\rm Y}(5S)$ peak in terms of the two $P$ wave contributions only. It is argued here that although at this energy the $F$ wave should be quite suppressed, especially for the strange-bottom vector mesons, the particular studied angular distribution is very sensitive to a presence of even small $F$ wave amplitude due to a significant interference with the dominant $S=2$ $P$ wave. Thus the available data are not conclusive with regards to the partial wave structure of the production amplitude. Additional angular correlations are discussed that can be measured for a full amplitude analysis of the production process.

    hep-phhep-exPRD(2017)·0 citations
15. 15*

    "Mass Without Mass" and Nuclear Matter

    Mannque Rho🇫🇷

    This is a brief account of the chief accomplishment of the 5-year activity (2008-2013) in the World Class University III Program at Hanyang University with the theme of exploring "From Dense Matter to Compact Stars." The principal objective was to explore and foresee what could be a break-through research that could be initiated at the RIB machine in project "RAON" at the upcoming ambitious Institute for Basic Science (IBS) in Korea. What came out was a possibility for unraveling the mystery of proton's "mass without mass" via nuclear matter and its impact on RAON-type physics and compact stars.

    ↳ nucl-thhep-ph1 citation
16. 16*

    Warm dark matter and the ionization history of the Universe

    Laura Lopez-Honorez🇧🇪 · Olga Mena🇪🇸 · Sergio Palomares-Ruiz🇪🇸 · Pablo Villanueva Domingo🇪🇸

    In warm dark matter scenarios structure formation is suppressed on small scales with respect to the cold dark matter case, reducing the number of low-mass halos and the fraction of ionized gas at high redshifts and thus, delaying reionization. This has an impact on the ionization history of the Universe and measurements of the optical depth to reionization, of the evolution of the global fraction of ionized gas and of the thermal history of the intergalactic medium, can be used to set constraints on the mass of the dark matter particle. However, the suppression of the fraction of ionized medium in these scenarios can be partly compensated by varying other parameters, as the ionization efficiency or the minimum mass for which halos can host star-forming galaxies. Here we use different data sets regarding the ionization and thermal histories of the Universe and, taking into account the degeneracies from several astrophysical parameters, we obtain a lower bound on the mass of thermal warm dark matter candidates of $m_X>1.3$ keV, or $m_s>5.5$ keV for the case of sterile neutrinos non-resonantly produced in the early Universe, both at 90\% confidence level.

    ↳ astro-ph.COhep-phPRD(2017)·53 citations
17. 17*

    Dark matter kinetic decoupling with a light particle

    Ayuki Kamada🇰🇷 · Tomo Takahashi🇯🇵

    We argue that the acoustic damping of the matter power spectrum is not a generic feature of the kinetic decoupling of dark matter, but even the enhancement can be realized depending on the nature of the kinetic decoupling when compared to that in the standard cold dark matter model. We consider a model that exhibits a $sudden$ kinetic decoupling and investigate cosmological perturbations in the $standard$ cosmological background numerically in the model. We also give an analytic discussion in a simplified setup. Our results indicate that the nature of the kinetic decoupling could have a great impact on small scale density perturbations.

    ↳ astro-ph.COhep-phJCAP(2018)·10 citations
18. 18*

    Anomalous Transport and Generalized Axial Charge

    Vladimir P. Kirilin🇺🇸 · Andrey V. Sadofyev🇺🇸

    In this paper we continue studying the modification of the axial charge in chiral media by macroscopic helicities. Recently it was shown that magnetic reconnections result in a persistent current of zero mode along flux tubes. Here we argue that in general a change in the helical part of the generalized axial charge results in the same phenomenon. Thus one may say that there is a novel realization of chiral effects requiring no initial chiral asymmetry. The transfer of flow helicity to zero modes is analyzed in a toy model based on a vortex reconnection in a chiral superfluid. Then, we discuss the balance between the two competing processes effect of reconnections and the chiral instability on the example of magnetic helicity. We argue that in the general case there is a possibility for the distribution of the axial charge between the magnetic and fermionic forms at the end of the instability.

    ↳ hep-thhep-phnucl-thPRD(2017)·33 citations
19. 19*

    Chiral heat wave in cold Fermi liquid and modified zero sound

    D. Frenklakh🇷🇺 · A. Gorsky🇷🇺

    We discuss kinetic equations involving the anomalous terms responsible for the chiral anomaly. The general chiral heat wave in cold Fermi liquid is described and the modification of the anomalous zero sound at small temperature and vorticity is found.

    ↳ hep-thcond-mat.mes-hallhep-phPRD(2017)·1 citation
20. 20*

    Sourcing Dark Matter and Dark Energy from $\alpha$-attractors

    Swagat S. Mishra🇮🇳 · Varun Sahni🇮🇳 · Yuri Shtanov🇺🇦

    Recently, Kallosh and Linde have drawn attention to a new family of superconformal inflationary potentials, subsequently called $\alpha$-attractors. The $\alpha$-attractor family can interpolate between a large class of inflationary models. It also has an important theoretical underpinning within the framework of supergravity. We demonstrate that the $\alpha$-attractors have an even wider appeal since they may describe dark matter and perhaps even dark energy. The dark matter associated with the $\alpha$-attractors, which we call $\alpha$-dark matter ($\alpha$DM), shares many of the attractive features of fuzzy dark matter, with $V(\phi )=\frac{1}{2}{m}^2{\phi }^2$, while having none of its drawbacks. Like fuzzy dark matter, $\alpha$DM can have a large Jeans length which could resolve the cusp-core and substructure problems faced by standard cold dark matter. $\alpha$DM also has an appealing tracker property which enables it to converge to the late-time dark matter asymptote, $⟨w⟩\simeq 0$, from a wide range of initial conditions. It thus avoids the enormous fine-tuning problems faced by the $m^2{\phi }^2$ potential in describing dark matter.

    ↳ gr-qcastro-ph.COhep-phhep-thJCAP(2017)·35 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.