Preface: International Conference on the Structure of Baryons (BARYONS' 10)
No abstract prepared.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
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Hyperon-nucleon and hyperon-hyperon interactions based on effective field theory
I report on recent progress in the description of baryon-baryon systems within chiral effective field theory. In particular, results for the hyperon-hyperon interaction as well as for strangeness S =-3 to -4 baryon-baryon systems, obtained to leading order are discussed. Preliminary results for the hyperon-nucleon interaction to next-to-leading order are presented.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Lattice QCD Study for Confinement in Hadrons
We study three subjects on quark confinement in hadrons in SU(3)c lattice QCD. From the accurate lattice calculation for more than 300 different patterns of three-quark (3Q) systems, we find that the static 3Q potential is well described by Y-Ansatz, i.e., the Coulomb plus Y-type linear potential. We also study the multi-quark (4Q, 5Q) potentials in lattice QCD, and find that they are well described by the one-gluon-exchange (OGE) Coulomb plus string-theoretical linear potential, which supports the infrared string picture even for the multi-quarks. The second subject is a lattice-QCD determination of the relevant gluonic momentum component for confinement. The string tension (confining force) is found to be almost unchanged even after cutting off the high-momentum gluon component above 1.5GeV in the Landau gauge. In fact, quark confinement originates from the low-momentum gluon below about 1.5GeV. Finally, we consider a possible gauge of QCD for the quark potential model, by investigating 'instantaneous inter-quark potential' in generalized Landau gauge, which describes a continuous change from the Landau gauge to the Coulomb gauge.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Dynamically generated hadron resonances
As an example of dynamically generated resonances we mention the interaction of vector mesons with baryons within the local hidden gauge formalism which gives rise to a large amount of such states, many of which can be associated to known resonances, while others represent predictions for new resonances. The width of these states coming from decay into pseudoscalar baryon is also addressed. We also mention recent states coming from {rho}{pi} interaction obtained with Faddeev equations.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Spectrum of baryons with one charm quark
Diquark is employed to study the spectrum of baryons with one charm quark and two light quark within the mass loaded flux tube model. The spin-orbit interaction is taken into account based on the heavy quark symmetry. Some observed {Lambda}{sub c} and {Xi}{sub c} baryons are systematically classified with suggested J{sup P} quantum numbers.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Charge radii of octet and decuplet baryons
The charge radii of the octet and decuplet baryons have been calculated in the framework of chiral constituent quark model ({chi}CQM) using a general parameterization (GP) method. Our results are comparable with the latest experimental studies as well as with other phenomenological models. The effects of SU(3) symmetry breaking and GP parameters pertaining to the one-, two- and three-quark contributions have also been investigated in detail.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
From Sitges to Dehra-Dun: a personal view of the needs and situation of neutrino nucleus interactions
The neutrino oscillation phenomena in solar, atmospheric and accelerator based experiments have been solidly established during the last decade, recent experiments are aiming at more precise measurements which requires better understanding of the interaction of neutrinos with matter. The International Workshop on Neutrino-Nucleus Interactions in the Few-GeV region (NUINT) is a series of workshops concentrating on low-energy (few GeV), neutrino-nucleus interactions. The goal of this series is to bring theorists and experimentalists from the nuclear and high-energy communities together to address the many challenges to understanding these complex interactions. NUINT workshop series was initiated in KEK (Japan) ten years ago with the goals of understanding the neutrino interactions and its applications to accelerator based and atmospheric neutrino oscillation experiments. An overview of the situation after the last Nuint workshop is discussed in this paper.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Neutrino Induced Pion Production at SciBooNE
We report measurements of neutrino induced pion production processes on carbon target with an average energy of {approx}0.8 GeV by SciBooNE experiment at Fermilab. These measurements are important inputs for current and future accelerator-based neutrino oscillation experiments in the interpretation of neutrino oscillation signals.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Cross-section Effects in the Super-Kamiokande Tau Appearance Analysis
In this talk, I explain the search for tau neutrino appearance in the atmospheric neutrino flux at Super-Kamiokande with a particular emphasis on the effect deep inelastic cross section uncertainties have on interpreting the result. In particular, I explain why the normalization of the DIS cross-section also needs to be treated as a parameter in the fit of tau normalization, and show how a neural net based on event parameters can separate various cross-section modes in the background sample.
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
Measurement of {nu}-bar{sub e}-e scattering cross section with CsI(Tl) detector array and the Beyond Standard Model constraints
A search of {nu}-bar{sub e}-e scattering cross section was carried out at the Kuo-Sheng nuclear power station. Based on 29882 and 7369 kg-days of reactor ON/OFF data, respectively, at an average reactor ON {nu}-bar{sub e} flux of 6.4x10{sup 12} cm{sup -2} s{sup -1}, the standard model (SM) electroweak interaction was probed at the squared 4-momentum transfer range of Q{sup 2}{approx}3x10{sup -6} GeV{sup 2}. The ratio of experimental to SM cross section was measured [1.08{+-}0.21(stat){+-}0.16(sys)]. We placed the constraints on the electroweak parameters (g{sub V},g{sub A}), corresponding to a weak mixing angle measurement of sin{sup 2}{theta}{sub W} = 0.251{+-}0.031(stat){+-}0.024(sys). A Point Contact Germanium Detector (PCGe) of mass 1 kg has been installed at a new underground laboratory 'China Jin-Ping Laboratory (CJPL)' in China.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Neutrino resonance production at very low momentum transfer
I look back at comparisons of CC neutrino resonance interaction data at very low Q{sup 2}, from seven experiments, compared to the predictions of current neutrino event generators. When compared to data, the generator models, primarily based on the model of Rein and Sehgal, overpredict the event rate at very low Q{sup 2} for samples that are enhanced in resonance {pi}{sup +} interactions.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Representing the vacuum polarization on de Sitter
Previous studies of the vacuum polarization on de Sitter have demonstrated that there is a simple, noncovariant representation of it in which the physics is transparent. There is also a cumbersome, covariant representation in which the physics is obscure. Despite being unwieldy, the latter form has a powerful appeal for those who are concerned about de Sitter invariance. We show that nothing is lost by employing the simple, noncovariant representation because there is a closed form procedure for converting its structure functions to those of the covariant representation. We also present a vastly improved technique for reading off the noncovariant structure functions from the primitive diagrams. And we discuss the issue of representing the vacuum polarization for a general metric background.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Order g{sup 2} susceptibilities in the symmetric phase of the Standard Model
Susceptibilities of conserved charges such as baryon minus lepton number enter baryogenesis computations, since they provide the relationship between conserved charges and chemical potentials. Their next-to-leading order corrections are of order g, where g is a generic Standard Model coupling. They are due to soft Higgs boson exchange, and have been calculated recently, together with some order g{sup 2} corrections. Here we compute the complete g{sup 2} contributions. Close to the electroweak crossover the soft Higgs contribution is of order g{sup 2}, and is determined by the non-perturbative physics at the magnetic screening scale.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Long-lived light mediator to dark matter and primordial small scale spectrum
We calculate the early universe evolution of perturbations in the dark matter energy density in the context of simple dark sector models containing a GeV scale light mediator. We consider the case that the mediator is long-lived, with lifetime up to a second, and before decaying it temporarily dominates the energy density of the universe. We show that for primordial perturbations that enter the horizon around this period, the interplay between linear growth during matter domination and collisional damping can generically lead to a sharp peak in the spectrum of dark matter density perturbation. As a result, the population of the smallest DM halos gets enhanced. Possible implications of this scenario are discussed.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
The fraternal WIMP miracle
We identify and analyze thermal dark matter candidates in the fraternal twin Higgs model and its generalizations. The relic abundance of fraternal twin dark matter is set by twin weak interactions, with a scale tightly tied to the weak scale of the Standard Model by naturalness considerations. As such, the dark matter candidates benefit from a “fraternal WIMP miracle”, reproducing the observed dark matter abundance for dark matter masses between 50 and 150 GeV. However, the couplings dominantly responsible for dark matter annihilation do not lead to interactions with the visible sector. The direct detection rate is instead set via fermionic Higgs portal interactions, which are likewise constrained by naturalness considerations but parametrically weaker than those leading to dark matter annihilation. The predicted direct detection cross section is close to current LUX bounds and presents an opportunity for the next generation of direct detection experiments.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Open-charm mesons in nuclear matter at finite temperature beyond the zero-range approximation
The properties of open charm mesons, D, D, D{sub s}, and D{sub s} in nuclear matter at finite temperature are studied within a self-consistent coupled-channel approach. The interaction of the low-lying pseudoscalar mesons with the ground-state baryons in the charm sector is derived from a t-channel vector-exchange model. The in-medium scattering amplitudes are obtained by solving the Lippmann-Schwinger equation at finite temperature including Pauli blocking effects, baryon dressing, as well as D, D, D{sub s}, and D{sub s} self-energies taking their mutual influence into account. We find that the in-medium properties of the D meson are affected by the D{sub s}-meson self-energy through the intermediate D{sub s}Y loops coupled to DN states. Similarly, dressing the D meson in the DY loops has an influence over the properties of the D{sub s} meson.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Publisher's Note: Charmonium production in relativistic heavy-ion collisions [Phys. Rev. C 84, 034907 (2011)]
No abstract prepared.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Search for chargino and neutralino production in final states with a Higgs boson and missing transverse momentum at s√=13 TeV with the ATLAS detector
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72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗