The muon density spectrum at large zenith angles

1968 ◽  
Vol 46 (10) ◽  
pp. S273-S277
Author(s):  
D. Alexander ◽  
B. Holyoak ◽  
M. G. Thompson ◽  
M. J. L. Turner
Keyword(s):  
Transverse Momentum ◽  
Zenith Angle ◽  
High Energy ◽  
Experimental Results ◽  
Density Spectrum ◽  
A Value

The frequency of coincident penetrating particles crossing an area 30 m2 at large zenith angles has been measured, and comparison is made with the results of calculations based upon a model of propagation of the EAS through the atmosphere. The experimental results regarding the rate of recording showers as a function of zenith angle do not agree with a mean transverse momentum of secondaries, in high-energy interactions, of 400 MeV/c, but indicate a value of 800 MeV/c. The variation of rate with zenith angle follows a [Formula: see text] law at large zenith angles. The density spectrum of the showers at large zenith angles has also been measured, and for the larger recorded densities this result is in better agreement with the theory incorporating a mean transverse momentum of 400 MeV/c than that incorporating a value of 800 MeV/c.

An Analysis of Conventional and Self-Aligned four Terminal Resistor Structures for The Determination of The Contact Resistivity from End Resistance Measurements

1986 ◽  
Vol 71 ◽  
Author(s):  
I. Suni ◽  
M. Finetti ◽  
K. Grahn
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Computer Model ◽  
Contact Resistivity ◽  
Experimental Results ◽  
The Finite Element Method ◽  
Model Based ◽  
A Value ◽  
And Diffusion

AbstractA computer model based on the finite element method has been applied to evaluate the effect of the parasitic area between contact and diffusion edges on end resistance measurements in four terminal Kelvin resistor structures. The model is then applied to Al/Ti/n+ Si contacts and a value of contact resistivity of Qc = 1.8×10−7.Ωcm2 is derived. For comparison, the use of a self-aligned structure to avoid parasitic effects is presented and the first experimental results obtained on Al/Ti/n+Si and Al/CoSi2/n+Si contacts are shown and discussed.

An anomaly in the specific heat below 3 °K of copper containing hydrogen

1969 ◽  
Vol 47 (14) ◽  
pp. 1485-1491 ◽  
Author(s):  
Neil Waterhouse
Keyword(s):  
Specific Heat ◽  
Molecular Hydrogen ◽  
Pure Copper ◽  
Solid Hydrogen ◽  
Rotational State ◽  
Experimental Results ◽  
Ortho Hydrogen ◽  
Temperature Range ◽  
A Value ◽  
Heat Curve

The specific heat of copper heated in hydrogen at 1040 °C has been measured over the temperature range 0.4 to 3.0 °K and found to be anomalous. The anomaly occurs in the same temperature range as the solid hydrogen λ anomaly which, in conjunction with evidence of ortho to para conversion of hydrogen in the sample, suggests the presence of molecular hydrogen in the copper. The anomaly reported by Martin for "as-received" American Smelting and Refining Company (ASARCO) 99.999+ % pure copper has been briefly compared with the present results. The form of the anomaly produced by the copper-hydrogen specimen has been compared with Schottky curves using the simplest possible model, that for two level splitting of the degenerate J = 1 rotational state of the ortho-hydrogen molecule.Maintenance of the copper-hydrogen sample at ~20 °K for approximately 1 week removed the "hump" in the specific heat curve. An equation of the form Cp = γT + (464.34/(θ0c)3)T3 was found to fit these experimental results and produced a value for γ which had increased over that for vacuumannealed pure copper by ~2%.

scholarly journals PHENIX heavy flavor highlights

2020 ◽  
pp. 2040006
Author(s):  
Takashi Hachiya
Keyword(s):  
Perturbative Qcd ◽  
Semileptonic Decay ◽  
Large Mass ◽  
High Energy ◽  
Gluon Density ◽  
Experimental Results ◽  
Heavy Flavor ◽  
Phenix Experiment ◽  
Heavy Flavor Production

Heavy flavor production is a sensitive probe of the initial gluon density in the nucleon and is modified by the entire evolution of the hot quark and gluon medium created in high-energy nucleus–nucleus collisions. Besides, it is a process that can be calculated by perturbative QCD because of their large mass. The PHENIX experiment at RHIC studied the heavy flavor productions for a broad momentum and rapidity ranges using single leptons from the semileptonic decay of charm and bottom hadrons, and dileptons from [Formula: see text] decays in [Formula: see text], [Formula: see text]A, and Au [Formula: see text] Au collisions at [Formula: see text][Formula: see text]200[Formula: see text]GeV. In these proceedings, the recent experimental results in [Formula: see text], Au [Formula: see text] Au, and the small collision systems are presented and the heavy flavor productions and their modifications are discussed.

scholarly journals Direct Photon Measurements with the ALICE Experiment at the LHC

Proceedings ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 1
Author(s):  
Erwann Masson ◽  
on behalf of the ALICE Collaboration
Keyword(s):  
Transverse Momentum ◽  
High Energy ◽  
Direct Photon ◽  
High Transverse Momentum ◽  
Alice Experiment ◽  
Direct Photons ◽  
Proton Proton ◽  
Small Systems ◽  
Energy Hadron

In high-energy hadron collisions, direct photons can be produced in various processes andare of particular interest to study the hot QCD medium since they escape it without being affected.These proceedings present the latest ALICE experiment results concerning direct photon productionin proton-proton (pp), proton-lead (p–Pb) and lead-lead (Pb–Pb) collisions. All measurements agreewith pQCD calculations at high transverse momentum (pT) and show no direct photon excess at lowpT in small systems while a low-pT signal is found in central Pb–Pb collisions.

scholarly journals Flow and correlation phenomena measurements in pp, pPb and PbPb collisions at CMS

2018 ◽  
Vol 172 ◽  
pp. 05005
Author(s):  
Sandra S. Padula
Keyword(s):  
Transverse Momentum ◽  
Collective Behavior ◽  
Quark Gluon Plasma ◽  
Frictional Resistance ◽  
Gluon Plasma ◽  
High Energy ◽  
Collective Flow ◽  
Particle Correlation ◽  
The Past ◽  
High Energy Collisions

The quark-gluon plasma created in high energy collisions of large nuclei exhibits strong anisotropic collective behavior as a nearly perfect fluid, flowing with little frictional resistance or viscosity. It has been investigated extensively over the past years employing two or more particle correlations. An overview of collective flow and particle correlation measurements at CMS as a function of transverse momentum, pseudorapidity, event multiplicity, for both charged hadrons or identified particles will be presented. These results are compared among pp, pPb and PbPb systems and several aspects of their intriguing similarities are discussed.

Design and Testing of a Can Combustor for a Small Gas Turbine Application

2013 ◽  
Author(s):  
K. V. L. Narayana Rao ◽  
N. Ravi Kumar ◽  
G. Ramesha ◽  
M. Devathathan
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Gas Turbines ◽  
Pressure Loss ◽  
High Energy ◽  
Experimental Results ◽  
High Mass ◽  
Test Facility ◽  
Design Requirements

Can type combustors are robust, with ease of design, manufacturing and testing. They are extensively used in industrial gas turbines and aero engines. This paper is mainly based on the work carried out in designing and testing a can type combustion chamber which is operated using JET-A1 fuel. Based on the design requirements, the combustor is designed, fabricated and tested. The experimental results are analysed and compared with the design requirements. The basic dimensions of the combustor, like casing diameter, liner diameter, liner length and liner hole distribution are estimated through a proprietary developed code. An axial flow air swirler with 8 vanes and vane angle of 45 degree is designed to create a re-circulation zone for stabilizing the flame. The Monarch 4.0 GPH fuel nozzle with a cone angle of 80 degree is used. The igniter used is a high energy igniter with ignition energy of 2J and 60 sparks per minute. The combustor is modelled, meshed and analysed using the commercially available ansys-cfx code. The geometry of the combustor is modified iteratively based on the CFD results to meet the design requirements such as pressure loss and pattern factor. The combustor is fabricated using Ni-75 sheet of 1 mm thickness. A small combustor test facility is established. The combustor rig is tested for 50 Hours. The experimental results showed a blow-out phenomenon while the mass flow rate through the combustor is increased beyond a limit. Further through CFD analysis one of the cause for early blow out is identified to be a high mass flow rate through the swirler. The swirler area is partially blocked and many configurations are analysed. The optimum configuration is selected based on the flame position in the primary zone. The change in swirler area is implemented in the test model and further testing is carried out. The experimental results showed that the blow-out limit of the combustor is increased to a good extent. Hence the effect of swirler flow rate on recirculation zone length and flame blow out is also studied and presented. The experimental results showed that the pressure loss and pattern factor are in agreement with the design requirements.

Fine structure in the charge ratio of muons at large zenith angles

1968 ◽  
Vol 46 (10) ◽  
pp. S309-S312 ◽  
Author(s):  
G. N. Kelly ◽  
P. K. MacKeown ◽  
S. S. Said ◽  
A. W. Wolfendale
Keyword(s):  
Fine Structure ◽  
Zenith Angle ◽  
Experimental Results ◽  
Charge Ratio

Preliminary experimental results are presented of observations on the charge ratio of muons as a function of energy and of angle at large zenith angles found using the Durham horizontal spectrograph. There is some evidence for a maximum of the charge ratio at about 20 GeV, the magnitude of which increases with increasing zenith angle. Possible explanations of the effect are discussed.

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