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91.
Fission fragments and other charged particles leave tracks of permanent damage in most of the insulating solids. Damage track
detectors are useful for personal dosimeters and for flux/dose determination of high-energy particles from accelerators or
cosmic rays. A detector that has its principal response at nucleon energy above 50 MeV is provided by the fission of Bi-209.
Neutrons produce the largest percentage of hadron dose in most high-energy radiation fields. In these fields, the neutron
spectrum is typically formed by low-energy neutrons (evaporation spectrum) and high-energy neutrons (knock-on spectrum). We
used Bi-fission detectors to measure neutron peak fluence and compared the result with the calculated value of neutron peak
fluence. For the exposure to 100 MeV we have used the iThemba Facility in South Africa. 相似文献
92.
We use rationalization method to study two-dimensional complex dynamical systems (shifted harmonic oscillator in complex plane) on the extended complex phase space (ECPS). The role and scope of the derived invariants in the context of various physical problems are highlighted. 相似文献
93.
94.
For lack of a better word, a number is called special if it has mutually distinct exponents in its canonical prime factorizaton for all exponents. Let V(x) be the number of special numbers ≤x. We will prove that there is a constant c>1 such that \(\displaystyle {V(x) \sim \frac {cx}{\log x}}\). We will make some remarks on determining the error term at the end. Using the explicit abc conjecture, we will study the existence of 23 consecutive special integers. 相似文献
95.
SINGH Anand P 《中国科学A辑(英文版)》2006,(11)
Let f and g be two permutable transcendental holomorphic maps in the plane. We shall discuss the dynamical properties of f, g and f o g and prove, among other things, that if either f has no wandering domains or f is of bounded type, then the Julia sets of f and f(g) coincide. 相似文献
96.
97.
S ANANTHAKUMAR J JAYABALAN ASHA SINGH SALAHUDDIN KHAN SUBHASH PRAJAPATI S MOORTHY BABU RAMA CHARI 《Pramana》2014,82(2):353-358
In this article, we report size-dependent measurement of the shift in peak of upconversion photoluminescence spectra compared to that of normal photoluminescence using a 800 nm femtosecond laser and its second harmonic. It has been shown that the upconversion photoluminescence is always red-shifted compared to that of normal PL in all the samples. By measuring the power-dependent upconversion photoluminescence (UCPL), it has been shown that the origin of UCPL from MPA-capped CdTe nanoparticles is mainly of two-photon absorption 相似文献
98.
S K SHARMA A J SINGH P K GUPTA P HEDAOO P K MUKHOPADHYAY K RANGANATHAN K S BINDRA S M OAK 《Pramana》2014,82(2):191-195
In a thermally birefringence-compensated linear cavity configuration, ~160 W of average green power by intracavity frequency doubling of AO Q-switched Nd:YAG/LBO-based laser is demonstrated. The corresponding optical to optical conversion efficiency is estimated to be ~ 12.7%. The pulse repetition rate is 20 kHz with the individual pulse duration of 73 ns. The beam quality parameter is measured to be 18. 相似文献
99.
We demonstrate the generation of an isotopically pure beam of laser-cooled Yb atoms by deflection using 1D-optical molasses. Atoms in a collimated thermal beam are first slowed using a Zeeman slower. They are then subjected to a pair of molasses beams inclined at 45° with respect to the slowed atomic beam. The slowed atoms are deflected and probed at a distance of 160 mm. We demonstrate the selective deflection of the bosonic isotope 174Yb and the fermionic isotope 171Yb. Using a transient measurement after the molasses beams are turned on, we find a longitudinal temperature of 41 mK. 相似文献
100.
A WAHID S KUNDU J S B SINGH A K SINGH A KHATTAR S K MAURYA J S DHUMAL K DASGUPTA 《Pramana》2014,82(2):445-449
A Michelson interferometer-based technique has been used to measure the deformation of dielectric-coated mirror, caused by an incident repetitive pulsed laser beam with high average power. Minimum measurable deformation of 17 nm is reported. 相似文献