The lidar equation solution depending on the laser radiation line width studies

2013 ◽  
Vol 22 (4) ◽  
pp. 244-249 ◽  
Author(s):  
V. E. Privalov ◽  
V. G. Shemanin

The development with time of the excitation of a transition between two atomic or molecular energy levels under the influence of monochromatic laser radiation is examined under conditions of strictly inhomogeneous line broadening due to such causes as doppler shift arising from translational velocity. The ratio of the number of molecules, N 2 , in an excited state to the total number, N , is calculated for various ratios of the intensity parameter β ═ E 0 μ / ħ to the half line-width ∆ , where E 0 is the amplitude of the electric field in the incident radiation and is the dipole moment matrix element for the transition. Excitation functions obtained in a previous paper (I) for various values of the ratio γ/β , where γ is the half line-width in the absence of inhomo­geneous broadening, are used to obtain the variation of N 2 / N with time under conditions of mixed broadening for various values of the ratio γ/∆ and γ/β , when the exciting radiation is in exact resonance with the central frequency of the transition.


1967 ◽  
Vol 26 (2) ◽  
pp. 82-83 ◽  
Author(s):  
I.M. Aref'iev ◽  
I.L. Fabelinskii ◽  
Yu.I. Kyzylasov ◽  
V.S. Starunov ◽  
G.I. Zaitzev

1976 ◽  
Vol 32 ◽  
pp. 49-55 ◽  
Author(s):  
F.A. Catalano ◽  
G. Strazzulla

SummaryFrom the analysis of the observational data of about 100 Ap stars, the radii have been computed under the assumption that Ap are main sequence stars. Radii range from 1.4 to 4.9 solar units. These values are all compatible with the Deutsch's period versus line-width relation.


Author(s):  
James B. Pawley

Past: In 1960 Thornley published the first description of SEM studies carried out at low beam voltage (LVSEM, 1-5 kV). The aim was to reduce charging on insulators but increased contrast and difficulties with low beam current and frozen biological specimens were also noted. These disadvantages prevented widespread use of LVSEM except by a few enthusiasts such as Boyde. An exception was its use in connection with studies in which biological specimens were dissected in the SEM as this process destroyed the conducting films and produced charging unless LVSEM was used.In the 1980’s field emission (FE) SEM’s came into more common use. The high brightness and smaller energy spread characteristic of the FE-SEM’s greatly reduced the practical resolution penalty associated with LVSEM and the number of investigators taking advantage of the technique rapidly expanded; led by those studying semiconductors. In semiconductor research, the SEM is used to measure the line-width of the deposited metal conductors and of the features of the photo-resist used to form them. In addition, the SEM is used to measure the surface potentials of operating circuits with sub-micrometer resolution and on pico-second time scales. Because high beam voltages destroy semiconductors by injecting fixed charges into silicon oxide insulators, these studies must be performed using LVSEM where the beam does not penetrate so far.


1977 ◽  
Vol 38 (C1) ◽  
pp. C1-267-C1-269 ◽  
Author(s):  
C. M. SRIVASTAVA ◽  
M. J. PATNI ◽  
N. G. NANADIKAR
Keyword(s):  

1983 ◽  
Vol 44 (C2) ◽  
pp. C2-19-C2-25
Author(s):  
M. C. Gower ◽  
R. G. Caro

1980 ◽  
Vol 41 (C4) ◽  
pp. C4-31-C4-36
Author(s):  
J. R. Meyer ◽  
F. J. Bartoli ◽  
M. R. Kruer

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