Ground and gamma band energy systematics in even xenon and barium nuclei

2010 ◽  
Vol 88 (3) ◽  
pp. 201-209
Author(s):  
Yuvraj Singh ◽  
Chhail Bihari ◽  
A. K. Varshney ◽  
S. K. Dhiman ◽  
K. K. Gupta ◽  
...  
Keyword(s):  
Coupling Parameter ◽  
Structural Evolution ◽  
Gamma Band ◽  
External Parameter ◽  
Yrast Band ◽  
Large Asymmetry ◽  
Inertia Parameters ◽  
Asymmetric Rotor ◽  
The Moment ◽  
Vibration Coupling

Rotation–vibration coupling parameter b at different spins is calculated on fitting the experimental energy for each nucleus in the framework of the General Asymmetric Rotor Model (Zhi. Phys. Rev. C, 51, 141 (1995)). Taking the even and odd spin energy sequences of the gamma band as separate bands besides the yrast band at large asymmetry (γ ≥ 20°), three values of the moment of inertia parameters a (ar, ae, and ao) are calculated from the band head energies. A striking correlation in a and b versus the product of the number of valance protons and neutrons (NpNn) is obtained. These trajectories and the γ versus NpNn correlation (Yan et al. Phys. Rev. C, 48, 1046 (1993)) are capable of predicting the unknown energies of the ground and gamma bands of even xenon and barium nuclei, knowing only an external parameter NpNn. This introduces the possibility of a simpler description of the structural evolution of these transitional nuclei.

In search of empirical rule relating E21+ and B(E2; 01+→21+) in asymmetric even–even nuclei of mass region A = 90–120

2013 ◽  
Vol 91 (10) ◽  
pp. 777-782
Author(s):  
Yuvraj Singh ◽  
S.K. Dhiman ◽  
M. Singh ◽  
Chhail Bihari ◽  
A.K. Varshney ◽  
...  
Keyword(s):  
Mass Region ◽  
Quadrupole Deformation ◽  
Nucl Phys ◽  
Yrast Band ◽  
Transition Rates ◽  
Empirical Rule ◽  
Asymmetric Rotor ◽  
The Moment ◽  
Rotor Model ◽  
Static Quadrupole

The quadrupole deformation β are extracted independently from energy and transition rates. The set of asymmetric parameters γ are obtained from energy ratio [Formula: see text]. It is observed that the set of β values evaluated from B(E2) are closer to the values of β extracted from [Formula: see text] on considering the Grodzins empirical rule (Grodzins. Phys. Lett. 2, 88 (1962)) with uncertainty in even Mo, Ru, and Pd nuclei. The moment of inertia [Formula: see text] generating the yrast band in these nuclei is evaluated from [Formula: see text] using the asymmetric rotor model (Davydov and Filippov. Nucl. Phys. 8, 237 (1958)). The β, γ, and I0 values have good correlations with NpNn. In addition, β and I0 are related linearly in general. This systematic relate [Formula: see text] [Formula: see text] and asymmetric deformation γ that enables one to predict [Formula: see text], the static quadrupole moment Q0 and quadrupole deformation β of those nuclei whose only [Formula: see text] is known.

scholarly journals Satellite Inertia Parameters Estimation Based on Extended Kalman Filter

2019 ◽  
Author(s):  
Abdellatif Bellar ◽  
Mohammed Arezki Si Mohammed
Keyword(s):  
Kalman Filter ◽  
Extended Kalman Filter ◽  
Critical Role ◽  
Low Earth Orbit ◽  
Parameters Estimation ◽  
Moment Of Inertia ◽  
Satellite Mission ◽  
Inertia Matrix ◽  
Inertia Parameters ◽  
The Moment

The moment of inertia parameters play a critical role in assuring the spacecraft mission throughout its lifetime. However, determination of the moment of inertia is a key challenge in operating satellites. During satellite mission, those parameters can change in orbit for many reasons such as sloshing, fuel consumption, etc. Therefore, the inertia matrix should be estimated in orbit to enhance the attitude estimation and control accuracy. This paper investigates the use of gyroscope to estimate the attitude rate and inertia matrix for low earth orbit satellite via extended Kalman filter. Simulation results show the effectiveness and advantages of the proposed algorithm in estimating these parameters without knowing the nominal inertia. The robustness of the proposed algorithm has been validated using the Monte-Carlo method. The obtained results demonstrate that the accuracy of the estimated inertia and angular velocity parameters is satisfactory for satellite with coarse accuracy mission requirements. The proposed method can be used for different types of satellites.

Shape co-existence and structural evolution of the yrast band in 157Yb

2002 ◽  
Vol 14 (2) ◽  
pp. 133-136 ◽  
Author(s):  
Y. Zheng ◽  
X.H. Zhou ◽  
Y.H. Zhang ◽  
Y.X. Guo ◽  
X.G. Lei ◽  
...  
Keyword(s):  
Structural Evolution ◽  
Yrast Band

Results from lunar laser ranging (summary only)

1977 ◽  
Vol 284 (1326) ◽  
pp. 587-587
Keyword(s):  
Three Dimensional ◽  
Lunar Laser Ranging ◽  
Lunar Laser Range ◽  
Lunar Laser ◽  
Inertia Parameters ◽  
Null Value ◽  
Rotation Of The Earth ◽  
The Moment ◽  
Geocentric Coordinates ◽  
Better Than

Over 1500 lunar laser range measurements have been made during the past six years at McDonald Observatory. These data have been fitted with a 41 cm r. m. s. residual. The geocentric coordinates of McDonald Observatory are now known to better than 1 m, the three-dimensional coordinates of the Moon and the selenocentric coordinates of the retroreflectors are accurate to about 25 m, and the mass ratio Sun/(Earth + Moon) is determined to 2 parts in 107. A search for the Nordtvedt term in the Moon’s orbit, a term predicted by some relativity theories, gives a null value, a result consistent with general relativity. The measurement of the physical librations determines very accurately the moment of inertia parameters β = (C - A)/B and γ = (B - A)/C, and significantly determines the third degree gravitational harmonics C 30 , C 32 , S 32 and S 33 The postfit residuals are not random but yield corrections to the rotation of the Earth, values of U. T. 0 for individual days having typical accuracies of 0.5 ms (20cm). The anticipated regular operation of two or more stations will allow the separation of U. T. 1 and polar motion.

Structural evolution of the early Miocene in the eastern Betic internal-external zone boundary (SE Spain)

2001 ◽  
Vol 172 (1) ◽  
pp. 41-47 ◽  
Author(s):  
Jose Enrique Tent-Manclu ◽  
Manuel Martin-Martin ◽  
Jose Antonio Martin-Perez ◽  
Francisco Serrano
Keyword(s):  
Planktonic Foraminifera ◽  
Structural Evolution ◽  
The Other ◽  
Calcareous Nannofossils ◽  
Zone Boundary ◽  
Geodynamic Evolution ◽  
Se Spain ◽  
External Zone ◽  
Internal Zone ◽  
The Moment

Abstract The Internal-External Zone boundary (IEZB) in the eastern Betic Cordillera partially coincides with the Cadiz-Alicante Accident, mainly a major transcurrent fault of N060E direction. The study of an area located along the IEZB at a point where it separates from the Cadiz-Alicante accident has provided details concerning the geodynamic evolution of the cordillera at the moment of its structuration. Here the Internal Zone, consists of rocks assigned to the Malaguide Complex, dating its last sedimentation to the Aquitanian, and deposits assigned to the Vinuela Group (early-middle Burdigalian). The nappes of the Internal Zone were emplaced during the latest Aquitanian and the Vinuela Group (here the El Nino Formation) sealed it but was afterwards affected by the collision with the External Zone. On the other side of the boundary, the External Zone comprises two tectonic units: the Penarrubia Unit (late Cretaceous-middle Burdigalian), which is made up mainly of limestones and marls, and the El Frances Chaotic Complex composed by a set of different lithologies, all from the External Zone in a marly matrix that could be interpreted as a collisional melange formed in the early-middle Burdigalian. The contact between the two domains corresponds to a backthrust of the External Zone over the Internal Zone which occurred in the middle Burdigalian. The deposits sealing the IEZB are dated by calcareous nannofossils and planktonic foraminifera as late Burdigalian, and comprise clasts from both domains.

ROTATIONAL STATES IN DEFORMED EVEN–EVEN NUCLEI

1967 ◽  
Vol 45 (11) ◽  
pp. 3521-3532 ◽  
Author(s):  
Raj K. Gupta
Keyword(s):  
Energy Levels ◽  
Spin States ◽  
Coupling Constant ◽  
Rotational States ◽  
Rotational Bands ◽  
High Spin States ◽  
Oscillator Type ◽  
The Moment ◽  
Vibration Coupling ◽  
Good Agreement

The deviations from the simple I(I + 1) dependence of the energy levels in the ground-state rotational bands on the hydrodynamical model of Bohr and Mottelson have been investigated for both regions of stable deformation. An interpretation of high spin states is looked for in terms of a nonrigid rotator with vibrations (harmonic oscillator type) taken as perturbation. In the framework of this model, the energy expression is obtained as a power series in the product of the ratio B/A and the weight factor I(I + 1), where A is related to the moment of inertia and B is the rotation–vibration coupling constant. The calculations are shown to be in good agreement with the experimental data.

Payload parameter identification method of flexible space manipulator

2020 ◽  
Vol 92 (6) ◽  
pp. 925-938
Author(s):  
Zhiyu Ni ◽  
Yewei Zhang ◽  
Xinhui Shen ◽  
Shunan Wu ◽  
Zhigang Wu
Keyword(s):  
Operating Conditions ◽  
Identification Accuracy ◽  
Identification Algorithm ◽  
Space Manipulator ◽  
Capture Process ◽  
Content Type ◽  
Identification Method ◽  
Inertia Parameters ◽  
The Difference ◽  
The Moment

Purpose When a manipulator captures an unknown space object, inertia parameters of endpoint payload should be timely obtained to handle possible unexpected parameter variations and monitor the system’s operating conditions. Therefore, this study aims to present an identification method for estimating the inertia parameter of the payload carried by a flexible two-link space manipulator. Design/methodology/approach The original nonlinear dynamics model of the manipulator is linearized at a selected working point. Subsequently, the system modal frequencies with and without payload are determined using the subspace identification algorithm, and the difference of these frequencies is computed. Furthermore, by adjusting the structural configuration of the manipulator, multiple sets of frequency differences are obtained. Therefore, the inertia parameters of the payload, i.e. the mass and the moment of inertia, can be derived from the frequency differences by solving a least-squares problem. Findings The proposed method can effectively estimate the payload parameters and has satisfactory identification accuracy. Practical implications The approach’s implementation provides a practical reference for determining inertia parameters of an unknown space target in the capture process. Originality/value The study proposes a novel method for identifying the inertia parameters of the payload of a flexible two-link space manipulator using the estimated system frequencies.

scholarly journals Angular distribution and inertia parameters i Alpha-induced fission of 232Th, 233U, and 238U

2003 ◽  
Vol 18 (1) ◽  
pp. 31-35 ◽  
Author(s):  
Farhad Rahimi ◽  
Omid Ghodsi ◽  
Aziz Behkami
Keyword(s):  
Angular Distribution ◽  
Transition State ◽  
Fission Fragment ◽  
Statistical Parameter ◽  
Theoretical Expression ◽  
Fragment Angular Distribution ◽  
Inertia Parameters ◽  
Induced Fission ◽  
The Moment ◽  
Experimental Values

The analysis of the selected fission fragment angular distribution from alpha induced fission is made by using an exact theoretical expression. Theoretical anisotropics obtained with transition state modes are compared with their corresponding experimental values. The agreement between the calculated and experimental values is very good. The values of the statistical parameter K02 are used for calculation of the inertia parameters. The results indicate an increase in the moment of inertia.

Evidence of rigid triaxiality in some xenon nuclei

2007 ◽  
Vol 85 (8) ◽  
pp. 899-910 ◽  
Author(s):  
M Singh ◽  
C Bihari ◽  
Y Singh ◽  
D Gupta ◽  
A K Varshney ◽  
...  
Keyword(s):  
Hilbert Space ◽  
Moment Of Inertia ◽  
Vibrational Band ◽  
Current Interest ◽  
Asymmetric Rotor ◽  
The Moment ◽  
21.60 Ev ◽  
Gamma Vibrational Band ◽  
Rotor Model

The present study deals with a topic of current interest, getting clear evidence for triaxiality in the 120–130 Xe nuclei near A = 130. The odd–even staggering in a so-called gamma-vibrational band may be treated using the asymmetric rotor model (ARM) on employing the Lipas parameter. The Hilbert space is too limited to describe the full variation of the moment of inertia and, therefore, the Lipas Ansatz ismade to correct the ARM energies, which conserve the good result for B(E2) values.PACS Nos.: 21.10.Re, 21.60.Ev, 27.60.+j

The High Resolution Scanning Transmission Electron Microscope

1974 ◽  
Vol 32 ◽  
pp. 316-317
Author(s):  
A. V. Crewe
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
High Vacuum ◽  
Scanning Transmission Electron Microscope ◽  
Ultra High Vacuum ◽  
Resolving Power ◽  
Imaging Characteristics ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
The Moment

The high resolution STEM is now a fact of life. I think that we have, in the last few years, demonstrated that this instrument is capable of the same resolving power as a CEM but is sufficiently different in its imaging characteristics to offer some real advantages.It seems possible to prove in a quite general way that only a field emission source can give adequate intensity for the highest resolution^ and at the moment this means operating at ultra high vacuum levels. Our experience, however, is that neither the source nor the vacuum are difficult to manage and indeed are simpler than many other systems and substantially trouble-free.

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