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61.
S.K. Katoch S.L. Gupta S.C. Pancholi D. Mehta S. Malik G. Shanker L. Chaturvedi R.K. Bhowmik 《The European Physical Journal A - Hadrons and Nuclei》1999,4(4):307-309
High-spin states in the odd-odd 168Lu nucleus, populated in the 154Sm(19F,5n) reaction at a beam energy of 96 MeV, were investigated using in-beam γ-ray spectroscopy techniques. The BC neutron crossing
in the yrast band, based on πg
7/2[404]7/2+⊗νi
13/2[642]5/2+ configuration, occurs at ħω= 0.31 MeV. The two side bands, based on πh
11/2[514]9/2−⊗νi
13/2[642]5/2+ and πh
9/2[541]1/2−⊗νi
13/2[642]5/2+ configurations, show anomalous signature-splitting and signature-inversion in the first one, to occur at ħω= 0.24 MeV. A
moderately delayed BC-crossing is anticipated in the second one.
Received: 15 June 1998 / Revised version: 11 January 1999 相似文献
62.
The density of states (DOS) of fcc and hcp structures of Al has been calculated for normal and high pressures. It has been found that the DOS of both structures, near the Fermi level, is similar over a range of compressed volumes close to the fcc-hcp transition volume (V/V0∼0.53). This similarity is the reason for the reported coexistence of fcc-hcp phases over a wide range of pressures near the fcc-hcp phase transition. All calculations have been performed using the FP-LAPW method with GGA. 相似文献
63.
Ranjan Das Balu Venkataraman Vinod R Bhagat Ajit S Ghangrekar Thomas Kuruvilla B K Chaturvedi G S Isola B M Marwaha P G Nair R S Parolia B K Sarkar 《Pramana》1986,27(5):661-677
A computer-controlled X-band time domain electron paramagnetic resonance (EPR) spectrometer, with a time resolution of the
order of 0.5μsec, has been constructed with many of the crucial microwave components designed and fabricated by the Microwave Engineering
Group of TIFR. The spectrometer operates either in a microwave power pulsed mode for determination of spin-lattice relaxation
times by the saturation recovery technique or in the kinetic mode for determination of the time dependence of EPR signal after
laser excitation. It has an automatic frequency control, an automatic phase control and, most importantly, a field-frequency
lock which ensures good stability of the EPR line positions enabling signal averaging for extended periods. The constructional
details of the spectrometer and its performance in both the modes are described here by reporting results on certain typical
systems. 相似文献
64.
A. V. Daniel J. H. Hamilton A. V. Ramayya A. S. Fomichev Yu. Ts. Oganessian G. S. Popeko A. M. Rodin G. M. Ter-Akopian J. K. Hwang D. Fong C. Goodin K. Li J. O. Rasmussen D. Seweryniak M. Carpenter C. J. Lister Sh. Zhu R. V. F. Janssens J. Batchelder J. Kliman L. Krupa W. -C. Ma S. J. Zhu L. Chaturvedi J. D. Cole 《Physics of Atomic Nuclei》2006,69(8):1405-1408
A new experiment devoted to the fission of 252Cf is described. It continued a series of our experiments based on correlation measurements of γ rays emitted by fission fragment pairs. The measurements of γ-γ and γ-γ-γ coincidences were done at Gammasphere with closed 252Cf sources. The open source was used for the first time in the last experiment. Fission fragment detectors were arranged in
the center hole of Gammasphere. Correlations between fission fragment masses, total kinetic energy, and γ rays were observed. The first, preliminary results of data analysis are discussed.
The text was submitted by the authors in English. 相似文献
65.
Subhajyoti Bandyopadhyay John M. Barron Alok R. Chaturvedi 《European Journal of Operational Research》2008
With the advent of open standards and Internet technologies, the number of sellers who can participate in online exchanges is greatly increased. We model the competition between identical sellers vying for the same business, and find that there exists a mixed-strategy equilibrium in prices. The results help us understand the dynamics between a seller’s capacity and his motivation to participate in an auction. 相似文献
66.
S Chaturvedi 《Pramana》2002,59(2):345-350
After a brief review of the notion of a full set of mutually unbiased bases in an N-dimensional Hilbert space, we summarize the work of Wootters and Fields (W K Wootters and B C Fields, Ann. Phys.
191, 363 (1989)) which gives an explicit construction for such bases for the case N=p
r
, where p is a prime. Further, we show how, by exploiting certain freedom in the Wootters-Fields construction, the task of explicitly
writing down such bases can be simplified for the case when p is an odd prime. In particular, we express the results entirely in terms of the character vectors of the cyclic group G of order p. We also analyse the connection between mutually unbiased bases and the representations of G. 相似文献
67.
Insana MF Cook LT Bilgen M Chaturvedi P Zhu Y 《The Journal of the Acoustical Society of America》2000,107(3):1421-1434
A maximum-likelihood (ML) strategy for strain estimation is presented as a framework for designing and evaluating bioelasticity imaging systems. Concepts from continuum mechanics, signal analysis, and acoustic scattering are combined to develop a mathematical model of the ultrasonic waveforms used to form strain images. The model includes three-dimensional (3-D) object motion described by affine transformations, Rayleigh scattering from random media, and 3-D system response functions. The likelihood function for these waveforms is derived to express the Fisher information matrix and variance bounds for displacement and strain estimation. The ML estimator is a generalized cross correlator for pre- and post-compression echo waveforms that is realized by waveform warping and filtering prior to cross correlation and peak detection. Experiments involving soft tissuelike media show the ML estimator approaches the Cramer-Rao error bound for small scaling deformations: at 5 MHz and 1.2% compression, the predicted lower bound for displacement errors is 4.4 microns and the measured standard deviation is 5.7 microns. 相似文献
68.
1:1:1, Rare earth ions-CDTA-hydroxy acids ternary systems have been studied pH-metrically. The formation constants (log KMLL′) and free energies of formation (ΔF°) of the resulting octa-coordinated metal ion mixed-ligand complexes have been calculated. The order of stability in terms of metal ions has been reported as: La < Pr < Nd < Gd < Dy and in terms of hydroxy acids as: TAR < MAL. 相似文献
69.
70.
In this paper, we consider a family of feasible generalised double k-class estimators in a linear regression model with non-spherical disturbances. We derive the large sample asymptotic distribution of the proposed family of estimators and compare its performance with the feasible generalized least squares and Stein-rule estimators using the mean squared error matrix and risk under quadratic loss criteria. A Monte-Carlo experiment investigates the finite sample behaviour of the proposed family of estimators. 相似文献