Size of the proton emission region in pion-xenon interactions at 3.5 GeV/c from two-particle correlations

1986 ◽  
Vol 324 (4) ◽  
pp. 471-475 ◽  
Author(s):  
J. Bartke ◽  
M. Kowalski ◽  
V. G. Grishin ◽  
K. Miller ◽  
J. Pluta ◽  
...  
Keyword(s):  
Emission Region ◽  
Proton Emission ◽  
Particle Correlations

Size of the proton emission region inp-C,d-C, ?-C and C-C interactions at 4.2 GeV/c per incident nucleon from two-proton correlations

1987 ◽  
Vol 327 (4) ◽  
pp. 443-446 ◽  
Author(s):  
G. N. Agakishiyev ◽  
R. R. Mekhteev ◽  
V. Boldea ◽  
S. Ditza ◽  
J. Bartke ◽  
...  
Keyword(s):  
Emission Region ◽  
Proton Emission ◽  
Incident Nucleon

Design of a Field-Emission Gun for the Phillips CM20/STEM microscope

1990 ◽  
Vol 48 (2) ◽  
pp. 100-101
Author(s):  
P.M. Mul ◽  
B.J.M. Bormans ◽  
L. Schaap
Keyword(s):  
High Resolution ◽  
Field Emission ◽  
Analytical Electron Microscopy ◽  
Emission Region ◽  
Attractive Alternative ◽  
Electron Holography ◽  
Field Emitter ◽  
Field Emitters ◽  
Resolution Electron ◽  
High Resolution Tem

The first Field Emission Guns (FEG) on TEM/STEM instruments were introduced by Philips in 1977. In the past decade these EM400-series microscopes have been very successful, especially in analytical electron microscopy, where the high currents in small probes are particularly suitable. In High Resolution Electron Holography, the high coherence of the FEG has made it possible to approach atomic resolution.Most of these TEM/STEM systems are based on a cold field emitter (CFE). There are, however, a number of disadvantages to CFE’s, because of their very small emission region: the maximum current is limited (a strong disadvantage for high-resolution TEM imaging) and the emission is unstable, requiring special measures to reduce the strong FEG-induced noise. Thermal field emitters (TFE), i.e. a zirconiated field emitter source operating in the thermal or Schottky mode, have been shown to be a viable and attractive alternative to CFE’s. TFE’s have larger emission regions, providing much higher maximum currents, better stability, and reduced sensitivity to vacuum conditions as well as mechanical and electrical interferences.

scholarly journals Imaging and SERS Study of the Au Nanoparticles Interaction with HPV and Carcinogenic Cervical Tissues

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3758
Author(s):  
Andrea Ceja-Fdez ◽  
Ramon Carriles ◽  
Ana Lilia González-Yebra ◽  
Juan Vivero-Escoto ◽  
Elder de la Rosa ◽  
...  
Keyword(s):  
Multiphoton Microscopy ◽  
Surface Enhanced Raman Spectroscopy ◽  
Rapid Screening ◽  
Emission Region ◽  
Sem Images ◽  
Spectral Signatures ◽  
Two Photon ◽  
Surface Enhanced ◽  
Surface Enhanced Raman ◽  
Gold Nps

In this work, gold NPs were prepared by the Turkevich method, and their interaction with HPV and cancerous cervical tissues were studied by scanning electron microscopy, energy-dispersive x-ray spectroscopy, confocal and multiphoton microscopy and SERS. The SEM images confirmed the presence and localization of the gold NPs inside of the two kinds of tissues. The light absorption of the gold NPs was at 520 nm. However, it was possible to obtain two-photon imaging (red emission region) of the gold NPs inside of the tissue, exciting the samples at 900 nm, observing the morphology of the tissues. The infrared absorption was probably due to the aggregation of gold NPs inside the tissues. Therefore, through the interaction of gold nanoparticles with the HPV and cancerous cervical tissues, a surface enhanced Raman spectroscopy (SERS) was obtained. As preliminary studies, having an average of 1000 Raman spectra per tissue, SERS signals showed changes between the HPV-infected and the carcinogenic tissues; these spectral signatures occurred mainly in the DNA bands, potentially offering a tool for the rapid screening of cancer.

scholarly journals Constraining the Chiral Magnetic Effect with charge-dependent azimuthal correlations in Pb-Pb collisions at $$ \sqrt{s_{\mathrm{NN}}} $$ = 2.76 and 5.02 TeV

2020 ◽  
Vol 2020 (9) ◽  
Author(s):  
S. Acharya ◽  
◽  
D. Adamová ◽  
A. Adler ◽  
J. Adolfsson ◽  
...  
Keyword(s):  
Charged Particles ◽  
Magnetic Effect ◽  
Anisotropic Flow ◽  
Charge Conservation ◽  
Particle Correlations ◽  
Azimuthal Correlations ◽  
Chiral Magnetic Effect ◽  
Local Charge ◽  
Peripheral Collisions ◽  
Dependent Signal

Abstract Systematic studies of charge-dependent two- and three-particle correlations in Pb-Pb collisions at $$ \sqrt{s_{\mathrm{NN}}} $$ s NN = 2.76 and 5.02 TeV used to probe the Chiral Magnetic Effect (CME) are presented. These measurements are performed for charged particles in the pseudorapidity (η) and transverse momentum (pT) ranges |η| < 0.8 and 0.2 < pT< 5 GeV/c. A significant charge-dependent signal that becomes more pronounced for peripheral collisions is reported for the CME-sensitive correlators γ1, 1 = 〈cos(φα + φβ − 2Ψ2)〉 and γ1, − 3 = 〈cos(φα − 3φβ + 2Ψ2)〉. The results are used to estimate the contribution of background effects, associated with local charge conservation coupled to anisotropic flow modulations, to measurements of the CME. A blast-wave parametrisation that incorporates local charge conservation tuned to reproduce the centrality dependent background effects is not able to fully describe the measured γ1,1. Finally, the charge and centrality dependence of mixed-harmonics three-particle correlations, of the form γ1, 2 = 〈cos(φα + 2φβ − 3Ψ3)〉, which are insensitive to the CME signal, verify again that background contributions dominate the measurement of γ1,1.

scholarly journals Pair-correlation ansatz for the ground state of interacting bosons in an arbitrary one-dimensional potential

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Przemysław Kościk ◽  
Arkadiusz Kuroś ◽  
Adam Pieprzycki ◽  
Tomasz Sowiński
Keyword(s):  
Boundary Conditions ◽  
Ground State ◽  
Pair Correlation ◽  
Contact Interactions ◽  
One Dimensional ◽  
Particle Correlations ◽  
Variational Scheme ◽  
Full Control ◽  
Arbitrary Shapes

AbstractWe derive and describe a very accurate variational scheme for the ground state of the system of a few ultra-cold bosons confined in one-dimensional traps of arbitrary shapes. It is based on assumption that all inter-particle correlations have two-body nature. By construction, the proposed ansatz is exact in the noninteracting limit, exactly encodes boundary conditions forced by contact interactions, and gives full control on accuracy in the limit of infinite repulsions. We show its efficiency in a whole range of intermediate interactions for different external potentials. Our results manifest that for generic non-parabolic potentials mutual correlations forced by interactions cannot be captured by distance-dependent functions.

Preequilibrium particles and mean-field effects from particle-particle correlations in heavy-ion collisions

1990 ◽  
Vol 514 (3) ◽  
pp. 564-588 ◽  
Author(s):  
D. Ardouin ◽  
Z. Basrak ◽  
P. Schuck ◽  
A. Péghaire ◽  
F. Saint-Laurent ◽  
...  
Keyword(s):  
Heavy Ion Collisions ◽  
Mean Field ◽  
Heavy Ion ◽  
Particle Correlations ◽  
Field Effects ◽  
Ion Collisions

scholarly journals Bacteria in the global atmosphere – Part 2: Modeling of emissions and transport between different ecosystems

2009 ◽  
Vol 9 (23) ◽  
pp. 9281-9297 ◽  
Author(s):  
S. M. Burrows ◽  
T. Butler ◽  
P. Jöckel ◽  
H. Tost ◽  
A. Kerkweg ◽  
...  
Keyword(s):  
Seasonal Variation ◽  
Residence Time ◽  
General Circulation ◽  
Bacterial Species ◽  
Circulation Model ◽  
Cloud Condensation Nucleus ◽  
Cloud Formation ◽  
Emission Region ◽  
Culturable Bacteria ◽  
Bacterial Cells

Abstract. Bacteria are constantly being transported through the atmosphere, which may have implications for human health, agriculture, cloud formation, and the dispersal of bacterial species. We simulate the global transport of bacteria, represented as 1 μm and 3 μm diameter spherical solid particle tracers in a general circulation model. We investigate factors influencing residence time and distribution of the particles, including emission region, cloud condensation nucleus activity and removal by ice-phase precipitation. The global distribution depends strongly on the assumptions made about uptake into cloud droplets and ice. The transport is also affected, to a lesser extent, by the emission region, particulate diameter, and season. We find that the seasonal variation in atmospheric residence time is insufficient to explain by itself the observed seasonal variation in concentrations of particulate airborne culturable bacteria, indicating that this variability is mainly driven by seasonal variations in culturability and/or emission strength. We examine the potential for exchange of bacteria between ecosystems and obtain rough estimates of the flux from each ecosystem by using a maximum likelihood estimation technique, together with a new compilation of available observations described in a companion paper. Globally, we estimate the total emissions of bacteria-containing particles to the atmosphere to be 7.6×1023–3.5×1024 a−1, originating mainly from grasslands, shrubs and crops. We estimate the mass of emitted bacteria- to be 40–1800 Gg a−1, depending on the mass fraction of bacterial cells in the particles. In order to improve understanding of this topic, more measurements of the bacterial content of the air and of the rate of surface-atmosphere exchange of bacteria will be necessary. Future observations in wetlands, hot deserts, tundra, remote glacial and coastal regions and over oceans will be of particular interest.

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