198 research outputs found
Muon groups and primary composition at 10 to the 13th power to 10 to the 15th power eV
The data on muon groups observed at Baksan underground scintillation telescope is analyzed. In this analysis we compare the experimental data with calulations, based on a superposition model in order to obtain the effective atomic number of primary cosmic rays in the energy range 10 to the 13th power to 10 to the 15th power eV
The scattering of muons in low Z materials
This paper presents the measurement of the scattering of 172 MeV/c muons in
assorted materials, including liquid hydrogen, motivated by the need to
understand ionisation cooling for muon acceleration.
Data are compared with predictions from the Geant 4 simulation code and this
simulation is used to deconvolute detector effects. The scattering
distributions obtained are compared with the Moliere theory of multiple
scattering and, in the case of liquid hydrogen, with ELMS. With the exception
of ELMS, none of the models are found to provide a good description of the
data. The results suggest that ionisation cooling will work better than would
be predicted by Geant 4.7.0p01.Comment: pdfeTeX V 3.141592-1.21a-2.2, 30 pages with 22 figure
Absorption spectrum in the wings of the potassium second resonance doublet broadened by helium
We have measured the reduced absorption coefficients occurring in the wings
of the potassium 4S-5P doublet lines at 404.414 nm and at 404.720 nm broadened
by helium gas at pressures of several hundred Torr. At the experimental
temperature of 900 K, we have detected a shoulder-like broadening feature on
the blue wing of the doublet which is relatively flat between 401.8 nm and
402.8 nm and which drops off rapidly for shorter wavelengths, corresponding to
absorption from the X doublet Sigma+ state to the C doublet Sigma+ state of the
K-He quasimolecule. The accurate measurements of the line profiles in the
present work will sharply constrain future calculations of potential energy
surfaces and transition dipole moments correlating to the asymptotes He-K(5p),
He-K(5s), and He-K(3d).Comment: 2 figure
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