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and #933;(1S+2S+3S) production in d+Au and p+p collisions at and #8730;sNN=200 GeV and cold-nuclear-matter effects
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Medium Modification of Jet Fragmentation in Au+Au Collisions at root SNN=200 and #8201; and #8201;GeV Measured in Direct Photon-Hadron Correlations
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The GeV Excess Shining Through: Background Systematics for the Inner Galaxy Analysis
Recently, a spatially extended excess of gamma rays collected by the Fermi-LAT from the inner region of the Milky Way has been detected by different groups and with increasingly sophisticated techniques. Yet, any final conclusion about the morphology and spectral properties of such an extended diffuse emission are subject to a number of potentially critical uncertainties, related to the high density of cosmic rays, gas, magnetic fields and abundance of point sources. We will present a thorough study of the systematic uncertainties related to the modelling of diffuse background and to the propagation of cosmic rays in the inner part of our Galaxy. We will test a large set of models for the Galactic diffuse emission, generated by varying the propagation parameters within extreme conditions. By using those models in the fit of Fermi-LAT data as Galactic foreground, we will show that the gamma-ray excess survives and we will quantify the uncertainties on the excess emission morphology and energy spectrum.
Measurement of transverse polarization of Λ and hyperons inside jets in unpolarized proton-proton collisions at $\sqrt{s}$ = 200 GeV
A surprisingly large transverse polarization of Λ hyperons in unpolarized hadron-nucleon/nucleus collisions has been observed for 50 years, and the origin of this polarization remains an important open question. Recently, theoretical frameworks have advanced in describing this puzzle with the polarizing fragmentation function (PFF). We report the first measurement of Λ and $\overline{Λ}$ transverse polarization inside jets in unpolarized proton-proton collisions, which is directly attributed to the PFF. The polarization is measured as a function of the jet transverse momentum, the fraction of the jet momentum carried by Λ ($\overline{Λ}$) hyperons, and the transverse momentum of Λ ($\overline{Λ}$) hyperons relative to the jet axis. Covering a wide jet-energy range, these data provide the first constraints on the gluon PFF and allow tests of TMD evolution and its universality.
Coleman-Weinberg dynamics of ultralight scalar dark matter and GeV-scale right-handed neutrinos
We consider an extension of the Standard Model by three singlet fermions and one singlet real scalar field. The scalar is an ultralight dark matter candidate whose abundance is set by dynamically induced misalignment from the Higgs portal. We focus on parameter space where the Coleman-Weinberg potential both fixes the dark matter relic abundance, and predicts the mass scale of right-handed neutrinos. The model prefers scalar masses in the range of 10 μeV ≲ m Φ ≲ 10 meV, and can be tested via direct searches for a light scalar (e.g. fifth force tests), or by searching for right-handed neutrinos in laboratory experiments.
Strangeness Production in √sNN = 3 GeV Au+Au Collisions at RHIC
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A 125 GeV fat Higgs at large tan β
In this article, we study the viability of regions of large tan β within the frame-work of Fat Higgs/λ-SUSY Models. We compute the one-loop effective potential to find the corrections to the Higgs boson mass due to the heavy non-standard Higgs bosons. As the tree level contribution to the Higgs boson mass is suppressed at large tan β, these one-loop corrections are crucial to raising the Higgs boson mass to the measured LHC value. By raising the Higgsino and singlino mass parameters, typical electroweak precision constraints can also be avoided. We illustrate these new regions of Fat Higgs/λ-SUSY parameter space by finding regions of large tan β that are consistent with all experimental constraints including direct dark matter detection experiments, relic density limits and the invisible decay width of the Z boson. We find that there exist regions around λ = 1.25, tan β = 50 and a uniform psuedo-scalar 4 TeV ≲ M A ≲ 8 TeV which are consistent will all present phenomenological constraints. In this region the dark matter relic abundance and direct detection limits are satisfied by a lightest neutralino that is mostly bino or singlino. As an interesting aside we also find a region of low tan β and small singlino mass parameter where a well-tempered neutralino avoids all cosmological and direct detection constraints.
The Ghent Hybrid model in NuWro: a new neutrino single-pion production model in the GeV regime
Neutrino-induced single-pion production constitutes an essential interaction channel in modern neutrino oscillation experiments, with its products building up a significant fraction of the observable hadronic final states. Frameworks of oscillation analyses strongly rely on Monte Carlo neutrino event generators, which provide theoretical predictions of neutrino interactions on nuclear targets. Thus, it is crucial to integrate state-of-the-art single-pion production models with Monte Carlo simulations to prepare for the upcoming systematics-dominated landscape of neutrino measurements. In this work, we present the implementation of the Ghent Hybrid model for neutrino-induced single-pion production in the NuWro Monte Carlo event generator. The interaction dynamics includes coherently-added contributions from nucleon resonances and a non-resonant background, merged into the pythia branching predictions in the deep-inelastic regime, as instrumented by NuWro. This neutrino-nucleon interaction model is fully incorporated into the nuclear framework of the generator, allowing it to account for the influence of both initial- and final-state nuclear medium effects. We compare the predictions of this integrated implementation with recent pion production data from accelerator-based neutrino experiments. The results of the novel model show improved agreement of the generator predictions with the data and point to the significance of the refined treatment of the description of pion-production processes beyond the ∆ region.
PHENIX study of dihadron Delta eta correlation in Au plus Au collision at root s(NN)=200 GeV: the ridge
We show the recent study of the ridge phenomena by PHENIX Collaboration over a broad transverse momentum (p{sub T}) range. Properties of the ridge are extracted in terms of its shape in {Delta}{phi} and {Delta}{eta}, and its yield. These properties are found to be similar to the away-side modification in the same p{sub T} range, suggesting a related modification mechanisms in both the near- and away-side.
Measured bremsstrahlung photonuclear production of 99Mo (99mTc) with 34 MeV to 1.7 GeV electrons
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Design of An 18-MW Vortex Flow Water Beam Dump for 500-GeV Electrons/Positrons of An International Linear Collider
Abstract Not Provided
Technical supplement to “Polarization transfer observables in elastic electron-proton scattering at Q 2 = 2 . 5 , 5 . 2 , 6 . 8 and 8 . 5 GeV 2 ”
Here, this technical note provides supplemental material for the archival publication of the measure- ments of polarization transfer observables in elastic e → p → e→p scattering from the GEp-III and GEp-2γ experiments in Jefferson Lab's Hall C.
High charge laser acceleration of electrons to 10 GeV
Not Available
Measurements and calculations of air activation in the NuMI neutrino production facility at Fermilab with the 120-GeV proton beam on target
Measurements and calculations of the air activation at a high-energy proton accelerator are described. The quantity of radionuclides released outdoors depends on operation scenarios including details of the air exchange inside the facility. To improve the prediction of the air activation levels, the MARS15 Monte Carlo code radionuclide production model was modified to be used for these studies. Measurements were done to benchmark the new model and verify its use in optimization studies for the new DUNE experiment at the Long Baseline Neutrino Facility (LBNF) at Fermilab. The measured production rates for the most important radionuclides – 11 C, 13 N, 15 O and 41 Ar – are in a good agreement with those calculated with the improved MARS15 code.