Condensate-enclosed chiral-bag model of the proton and pp elastic scattering at LHC 13 TeV

Our investigation of high energy [Formula: see text] and [Formula: see text] elastic scattering over the last ten years has led us to consider that the proton has three regions: (i) an outer region consisting of a quark–antiquark [Formula: see text] condensate ground state (also described as quark–antiquark outer cloud), (ii) an inner shell of topological (geometrical) baryonic charge of size [Formula: see text] 0.44 fm, and (iii) a core of size [Formula: see text] 0.2 fm, where the three valence quarks of a proton with baryonic charges are confined. The proton structure that has emerged leads to four main elastic scattering processes in [Formula: see text] scattering. The first process (which gives rise to diffraction scattering) is described by a profile function. The second process involves multiple [Formula: see text]-exchanges. The third process in [Formula: see text] scattering is quark–quark scattering via gluon–gluon interaction. The fourth process — which appears for the first time in our investigation of [Formula: see text] scattering — is a glancing collision at the boundary of a proton with that of the other proton. To describe quantitatively the four processes, their parameters have to be determined. For this purpose, we investigate: (i) [Formula: see text] 7 TeV [Formula: see text] measured by the TOTEM Collaboration and (ii) [Formula: see text] 1.96 TeV [Formula: see text] measured by the D0 Collaboration. Once the parameters are satisfactorily obtained, we calculate [Formula: see text] [Formula: see text] at 7 TeV and compare with the TOTEM data. We also calculate [Formula: see text] [Formula: see text] at 1.96 TeV and compare with the D0 data. We then predict [Formula: see text] elastic [Formula: see text] at 13 TeV which will soon be measured at LHC by the TOTEM Collaboration. This measurement will establish how well we have predicted the 13 TeV [Formula: see text] and determined the structure of the proton.

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A HYPOTHETICAL, ATTRACTIVE LONG-RANGE FORCE FROM TWO-GLUON EXCHANGE, AND THE MEASUREMENT OF ρ IN HIGH ENERGY $\bar p p$ ELASTIC SCATTERING

Modern Physics Letters A ◽

10.1142/s0217732394001696 ◽

1994 ◽

Vol 09 (20) ◽

pp. 1835-1844 ◽

Cited By ~ 1

Author(s):

S. BARSHAY ◽

J.A. GRIFOLS ◽

S. TORTOSA

Keyword(s):

Elastic Scattering ◽

Long Range ◽

Scattering Amplitude ◽

High Energy ◽

Small Momentum ◽

Energy Formula ◽

Nuclear Amplitude ◽

Energy Bar ◽

Coulomb Amplitude ◽

Range Force

The dynamical question is raised of the possible existence of long-range, residual attractive forces between hadrons due to the overall color-neutral exchange of two, massless transverse gluons between their constituents. Such a force between fermionic constituents would behave as 1/R6. We discuss the experiments which measure the real part of the nuclear amplitude, through its interference with the Coulomb amplitude in high energy [Formula: see text] elastic scattering at very small momentum transfers. We show that on-going [Formula: see text] experiments at [Formula: see text] and at 1800 GeV are sensitive to the scattering amplitude from a residual long-range force.

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Mechanochemical Synthesis and Nitrogenation of the Nd1.1Fe10CoTi Alloy for Permanent Magnet

Molecules ◽

10.3390/molecules26133854 ◽

2021 ◽

Vol 26 (13) ◽

pp. 3854

Author(s):

Hugo Martínez Sánchez ◽

George Hadjipanayis ◽

Germán Antonio Pérez Alcázar ◽

Ligia Edith Zamora Alfonso ◽

Juan Sebastián Trujillo Hernández

Keyword(s):

Mechanochemical Synthesis ◽

Applied Field ◽

Volume Fraction ◽

Synthesis Method ◽

High Energy ◽

Direction Parallel ◽

Best Value ◽

Heat Treated ◽

Bcc Phase ◽

First Time

In this work, the mechanochemical synthesis method was used for the first time to produce powders of the nanocrystalline Nd1.1Fe10CoTi compound from Nd2O3, Fe2O3, Co and TiO2. High-energy-milled powders were heat treated at 1000 °C for 10 min to obtain the ThMn12-type structure. Volume fraction of the 1:12 phase was found to be as high as 95.7% with 4.3% of a bcc phase also present. The nitrogenation process of the sample was carried out at 350 °C during 3, 6, 9 and 12 h using a static pressure of 80 kPa of N2. The magnetic properties Mr, µ0Hc, and (BH)max were enhanced after nitrogenation, despite finding some residual nitrogen-free 1:12 phase. The magnetic values of a nitrogenated sample after 3 h were Mr = 75 Am2 kg–1, µ0Hc = 0.500 T and (BH)max = 58 kJ·m–3. Samples were aligned under an applied field of 2 T after washing and were measured in a direction parallel to the applied field. The best value of (BH)max~114 kJ·m–3 was obtained for 3 h and the highest µ0Hc = 0.518 T for 6 h nitrogenation. SEM characterization revealed that the particles have a mean particle size around 360 nm and a rounded shape.

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Insights on forming N,O-coordinated Cu single-atom catalysts for electrochemical reduction CO2 to methane

Nature Communications ◽

10.1038/s41467-020-20769-x ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Yanming Cai ◽

Jiaju Fu ◽

Yang Zhou ◽

Yu-Chung Chang ◽

Qianhao Min ◽

...

Keyword(s):

Energy Barrier ◽

Active Sites ◽

Theoretical Calculations ◽

High Energy ◽

Single Atom ◽

Faradaic Efficiency ◽

High Energy Barrier ◽

Catalytic Sites ◽

Electron Reduction ◽

First Time

AbstractSingle-atom catalysts (SACs) are promising candidates to catalyze electrochemical CO2 reduction (ECR) due to maximized atomic utilization. However, products are usually limited to CO instead of hydrocarbons or oxygenates due to unfavorable high energy barrier for further electron transfer on synthesized single atom catalytic sites. Here we report a novel partial-carbonization strategy to modify the electronic structures of center atoms on SACs for lowering the overall endothermic energy of key intermediates. A carbon-dots-based SAC margined with unique CuN2O2 sites was synthesized for the first time. The introduction of oxygen ligands brings remarkably high Faradaic efficiency (78%) and selectivity (99% of ECR products) for electrochemical converting CO2 to CH4 with current density of 40 mA·cm-2 in aqueous electrolytes, surpassing most reported SACs which stop at two-electron reduction. Theoretical calculations further revealed that the high selectivity and activity on CuN2O2 active sites are due to the proper elevated CH4 and H2 energy barrier and fine-tuned electronic structure of Cu active sites.

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