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Development of the Detector Array for Photons, Protons, and Exotic Residues
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Halide Substitution Effects on Lithium-Ion Diffusion in Protonated Antiperovskites
Solid-state electrolytes (SSEs) for all-solid-state lithium-ion batteries are generating intense interest because these batteries can improve the safety and performance compared with devices fabricated with conventional, flammable liquid electrolytes. In these SSEs, it has been suggested that Li + ion diffusion in the grain boundaries is hindered and is a critical determinant of the overall ionic conductivity (σ). However, Li + ion diffusivities in the grain (D G ) and the grain boundary (D GB ) are difficult to determine experimentally, with few techniques capable of distinguishing the individual contributions. Here, we distinguished the D G and D GB for the protonated lithium antiperovskites (pLiAPs) SSEs: Li 2 OHCl, Li 2 OHBr, Li 2 OHF 0.1 Cl 0.9 , Li 2 OHF 0.1 Br 0.9 , and Li 2 OHCl 0.3 7Br 0.63 . The measurements were obtained directly from 7 Li pulsed-field gradient nuclear magnetic resonance (PFG-NMR) at 353 K. The 7 Li PFG-NMR echo profiles were composed of two primary components with additional secondary oscillatory components – the so-called NMR diffraction phenomenon. The length scale separating the two main components corresponds to a diffusion length of ~1.7 µm, which is thought to be the average grain size (by diameter). The short-range (≤ 1.7 µm) diffusion component associated with D G (≈10 -11 m 2 /s) varied minimally with halide substitution, while the long-range (≥ 1.7 µm) component D GB (≈10 -12 to 10 -15 m 2 /s) was highly sensitive to the substitution of halides and closely correlated with s. In addition, from the comparison of the ratio D GB /D G to D t (the Li + ion diffusion coefficient estimated from the rotational correlation time, t c ), it was determined that the contribution of D G to σ is negligible; 0.01 ~ 0.04 in the pLiAPs studied here. Finally, these insights provide fundamental understanding of the halide substitution effects on Li + ion grain versus grain boundary diffusion, and suggest that careful engineering of the grain boundaries at the microscopic level is necessary to achieve high-performance pLiAP SSEs.
Structural and proton conductivity studies of fibrous π-Ti 2 O(PO 4 ) 2 ·2H 2 O: application in chitosan-based composite membranes
The structure of π-Ti 2 O(PO 4 ) 2 ·2H 2 O was determined by the SR-PXRD method. The proton conductivity of chitosan/π-TiP membranes reached 4.5 × 10 −3 S cm −1 at 95%-RH.
Laser-to-proton conversion efficiency studies for proton fast ignition
We assess the conversion efficiency from intense picosecond laser pulses to multi-MeV ion beams for a wide range of laser and target parameters, using 2D kinetic particle-in-cell simulations. Scalings are addressed in a quasi-one-dimensional geometry, leaving out beam divergence. Then, we study the conversion efficiency into a narrow spatial band along the laser axis for flat and hemispherical targets in large-scale 2D simulations. Combining these findings allows us to calculate the energy requirements for ignition of a compressed ICF target with an intense proton beam in a fast-ignition scenario.
Final SeaQuest Results on the Flavor Asymmetry of the Proton Light-Quark Sea with Proton-Induced Drell-Yan Process
The Fermilab E906/SeaQuest collaboration performed measurements of the Drell-Yan process using 120 GeV proton beams bombarding liquid hydrogen and liquid deuterium targets. A combined analysis of all collected data was performed to obtain the final results for the 𝜎 𝑝𝑑 /2𝜎 𝑝𝑝 Drell-Yan cross section ratio covering the kinematic region of 0.13 < 𝑥 <0.45. The 𝑥 dependencies of $\bar{d}$(𝑥)/$\bar{𝑢}$(𝑥) and $\bar{d}$(𝑥) $-$ $\bar{𝑢}$(𝑥) are extracted from these cross section ratios. It is found that $\bar{d}$(𝑥) is greater than $\bar{𝑢}$(𝑥) over the entire measured 𝑥 range, with improved statistical accuracy compared to previous measurements. The new results on $\bar{d}$(𝑥)/$\bar{𝑢}$(𝑥) and $\bar{d}$(𝑥) $-$ $\bar{𝑢}$(𝑥) are compared to various parton distribution functions and theoretical calculations.
Final-state interactions in neutrino-induced proton knockout from argon in MicroBooNE
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Hard color-singlet exchange in dijet events in proton-proton collisions at $\sqrt{s} = 13$ TeV
We present a measurement of events with two jets separated by a pseudorapidity gap (jet-gap-jet). The signature is expected from hard color-singlet exchange. The jets are reconstructed with the CMS detector. The highest p_\text{T} p T jets have p_\text{T}^\text{jet1,2} > 40 p T jet1,2 > 40 GeV, with 1.4 < |\eta^\text{jet1,2}| < 4.7 1.4 < | η jet1,2 | < 4.7 and \eta^\text{jet1} \eta^\text{jet2} < 0 η jet1 η jet2 < 0 . We measure the fraction of color-singlet exchange dijet events, f_\text{CSE} f CSE , and compare it to previous measurements and to predictions. We also study jet-gap-jet events where the colliding protons remain intact and are detected with the Roman pots of TOTEM. A larger fraction f_\text{CSE} f CSE is found in the latter subsample.
Secondary-dose equivalent model and comparison of 160-MeV proton-induced neutron and proton dose with a comprehensive experiment
Secondary proton and neutron dose equivalent model calculations of random position, kinetic energy, and survival weight
The radial diffusion coefficient of 1.3 - 2.3 MeV protons in recurrent proton streams
The paper presents anisotropy measurements of 1.3-2.3 MeV protons in the interplanetary space during recurrent events for which the radial intensity variation is measured within the radial range from about 0.3 to about 4 AU for the period from June, 1973 through April, 1976. The simultaneous measurements of the diffusive anisotropy and the radial gradient are used to make a direct estimate of the interplanetary radial diffusion coefficient, which is independent of any particular solution of the propagation equation. IMP 7 and 8 is required to be sunward of the earth and hence outside of the magnetosphere; if both spacecraft are sunward, measurements from the one farthest from the magnetosphere are used. The resulting values for the radial diffusivity coefficient near 1 AU lie in the range (3 to 9) x 10 to the 20th sq cm/sec, corresponding to scattering mean free paths between 0.03 and 0.1 AU with a mean of 0.06 AU.
The Influence of Extremely Large Solar Proton Events in a Changing Stratosphere. Stratospheric Influence of Solar Proton Events
Two periods of extremely large solar proton events (SPEs) occurred in the past thirty years, which forced significant long-term polar stratospheric changes. The August 2-10, 1972 and October 19-27, 1989 SPEs happened in stratospheres that were quite different chemically. The stratospheric chlorine levels were relatively small in 1972 (approximately 1.2 ppbv) and were fairly substantial in 1989 at about (approximately 3 ppbv). Although these SPEs produced both HO(x) and NO(y) constituents in the mesosphere and stratosphere, only the NO(y) constituents had lifetimes long enough to affect ozone for several months to years past the events. Our recently improved two-dimensional chemistry and transport atmospheric model was used to compute the effects of these gigantic SPEs in a changing stratosphere. Significant upper stratospheric ozone depletions > 10% are computed to last for a few months past these SPEs. The long-lived SPE-produced NO(y) constituents were transported to lower levels during winter after these huge SPEs and caused impacts in the middle and lower stratosphere. During periods of high halogen loading these impacts resulted in interference with the chlorine and bromine loss cycles for ozone destruction. The chemical state of the atmosphere, including the stratospheric sulfate aerosol density, substantially affected the predicted stratospheric influence of these extremely large SPEs.
Results on total and elastic cross sections in proton–proton collisions at s = 200 GeV
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Concerted Electron-Nuclear Motion in Proton-Coupled Electron Transfer-Driven Grotthuss-Type Proton Translocation
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The Role of High-Energy Proton Beams in Advancing Tomorrow’s Technology: The Need for Proton Testing Currently
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Erratum to: Search for the HH → $ b\overline{b}b\overline{b} $ process via vector-boson fusion production using proton-proton collisions at $ \sqrt{s} $ = 13 TeV with the ATLAS detector
One correction is noted for the paper. A wrong cross-section was used for the theory prediction in figure 6 due to not taking into account the VHH contamination properly in the rescaling formula for the signal samples.
Search for dark photons in Higgs boson production via vector boson fusion in proton-proton collisions at $ \sqrt{s} $ = 13 TeV
A search is presented for a Higgs boson that is produced via vector boson fusion and that decays to an undetected particle and an isolated photon. The search is performed by the CMS collaboration at the LHC, using a data set corresponding to an integrated luminosity of 130 fb$^{−1}$, recorded at a center-of-mass energy of 13 TeV in 2016–2018. No significant excess of events above the expectation from the standard model background is found. The results are interpreted in the context of a theoretical model in which the undetected particle is a massless dark photon. An upper limit is set on the product of the cross section for production via vector boson fusion and the branching fraction for such a Higgs boson decay, as a function of the Higgs boson mass. For a Higgs boson mass of 125 GeV, assuming the standard model production rates, the observed (expected) 95% confidence level upper limit on the branching fraction is 3.5 (2.8)%. This is the first search for such decays in the vector boson fusion channel. Combination with a previous search for Higgs bosons produced in association with a Z boson results in an observed (expected) upper limit on the branching fraction of 2.9 (2.1)% at 95% confidence level.[graphic not available: see fulltext]
Erratum to: Search for the HH → $ b\overline{b}b\overline{b} $ process via vector-boson fusion production using proton-proton collisions at $ \sqrt{s} $ = 13 TeV with the ATLAS detector
One correction is noted for the paper. A wrong cross-section was used for the theory prediction in figure 6 due to not taking into account the VHH contamination properly in the rescaling formula for the signal samples. The change in the theory prediction leads to stricter exclusion limits on the di-vector-boson–di-Higgs-boson coupling modifier κ 2V . The observed excluded region corresponds to κ 2V < –0.43 and κ 2V > 2.56, while the expected exclusion is κ 2V < –0.55 and κ 2V > 2.72. Erratum JHEP 01 (2021) 145 fixed the description in the text but contains the uncorrected figure. The correct figure is shown in the new erratum.
Measurements of the Higgs boson production cross section in the four-lepton final state in proton-proton collisions at $\sqrt{s}$ = 13.6 TeV
The measurements of the Higgs boson (H) production cross sections performed by the CMS Collaboration in the four-lepton (4ℓ, ℓ = e, μ) final state at a center-of-mass energy $\sqrt{s}$ = 13.6 TeV are presented. These measurements are based on data collected with the CMS detector at the CERN LHC in 2022, corresponding to an integrated luminosity of 34.7 fb −1 . Cross sections are measured in a fiducial region closely matching the experimental acceptance, both inclusively and differentially, as a function of the transverse momentum and the absolute value of the rapidity of the four-lepton system. The H → ZZ → 4ℓ inclusive fiducial cross section is measured to be ${2.89}_{-0.49}^{+0.53}{\left({\text{stat}}\right)}_{-0.21}^{+0.29}\left({\text{syst}}\right)$ fb, in agreement with the standard model expectation of ${2.89}_{-0.49}^{+0.53}{\left({\text{stat}}\right)}_{-0.21}^{+0.29}\left({\text{syst}}\right)$ fb.