Nucleon Separation and Pairing Energies, Decay Energies, and Atomic Masses for

1972 ◽  
Vol 50 (11) ◽  
pp. 1195-1219 ◽  
Author(s):  
J. O. Meredith ◽  
R. C. Barber
Keyword(s):  
Rare Earth ◽  
Least Squares ◽  
Nuclear Reaction ◽  
Mass Spectra ◽  
Atomic Mass ◽  
Pairing Energy ◽  
Least Squares Adjustment ◽  
The Masses ◽  
Proton Pairing ◽  
Q Values

A set of 45 precise determinations of doublet spacings in the mass spectra of rare-earth chlorides has been combined with existing nuclear reaction and decay Q values and atomic mass data in a least-squares adjustment of atomic mass differences. For nuclides in the region [Formula: see text] the following quantities have been calculated: separation energies for the last pair of neutrons and for the last neutron (S2n, Sn), the neutron pairing energy (Pn), separation energies for the last pair of protons and for the last proton (S2p, Sp), the proton pairing energy (Pp), Q values for α and β− decays, and the masses. The systematic variations of these quantities are illustrated and discussed.

Nucleon separation and pairing energies, decay energies, and atomic masses for 68 ≤ Z ≤ 72

1977 ◽  
Vol 55 (15) ◽  
pp. 1360-1378 ◽  
Author(s):  
K. S. Sharma ◽  
J. O. Meredith ◽  
R. C. Barber ◽  
K. S. Kozier ◽  
S. S. Haque ◽  
...  
Keyword(s):  
Least Squares ◽  
Nuclear Reaction ◽  
Mass Difference ◽  
Atomic Mass ◽  
Mass Defect ◽  
Pairing Energy ◽  
Least Squares Adjustment ◽  
Proton Pairing ◽  
Q Values

A set of 24 precise determinations of mass spectroscopic doublet spacings, including a new determination of the 176Hf35Cl – 174Hf37Cl mass difference, has been combined with nuclear reaction and decay Q values in a least squares adjustment of the atomic mass differences in the region 68 ≤ Z ≤ 72. The following quantities have been calculated for each nuclide: separation energies for the last neutron and last pair of neutrons (Sn, S2n), the neutron pairing energy (Pn), separation energies for the last proton and last pair of protons (Sp, S2p), the proton pairing energy (Pp), Q values for α and β− decays, and the mass defect. The systematic variations of these quantities with N and Z are discussed.

Neutron Separation Energies of Zr Isotopes

1976 ◽  
Vol 31 (3-4) ◽  
pp. 393-394 ◽  
Author(s):  
L. C. Gomes ◽  
O. Dietzsch
Keyword(s):  
Stable Isotopes ◽  
Atomic Mass ◽  
The Masses ◽  
Q Values

Q values are reported for (d, t) reactions on all the stable isotopes of zirconium. The neutron separation energies of 94Zr and 96Zr differ greatly (by 27.5 and 22.1 keV, respectively) from the values in the 1971 Atomic Mass Evaluation. These results combined with those from other authors seem to indicate that the 1971 values for the masses of 93Zr and 95Zr are in error.

Precise Atomic Mass Differences for

1974 ◽  
Vol 52 (23) ◽  
pp. 2386-2394 ◽  
Author(s):  
R. C. Barber ◽  
J. W. Barnard ◽  
D. A. Burrell ◽  
J. O. Meredith ◽  
F. C. G. Southon ◽  
...  
Keyword(s):  
High Resolution ◽  
Nuclear Reaction ◽  
Mass Spectrometer ◽  
Atomic Mass ◽  
Computer Assisted ◽  
Naturally Occurring ◽  
High Resolution Mass ◽  
High Resolution Mass Spectrometer ◽  
Q Values ◽  
Resolution Mass

A high resolution mass spectrometer has been used to determine new values for 16 atomic mass differences involving naturally occurring isotopes for [Formula: see text]. These new determinations, which were derived by means of a computer assisted peak matching system, have a precision ranging from 0.6 to 2.0 μu (0.6 to 1.8 keV) and thus are generally more precise than the corresponding nuclear reaction or decay Q values available in the region.

Precise atomic mass differences amongst isotopes of Hg, Tl, Pb, and Bi (and a least-squares mass evaluation for 78 ≤ Z ≤ 84)

1985 ◽  
Vol 63 (7) ◽  
pp. 966-972 ◽  
Author(s):  
V. P. Derenchuk ◽  
R. J. Ellis ◽  
K. S. Sharma ◽  
R. C. Barber ◽  
H. E. Duckworth
Keyword(s):  
High Resolution ◽  
Least Squares ◽  
Mass Spectrometer ◽  
Atomic Mass ◽  
Mass Spectral ◽  
Least Squares Adjustment ◽  
University Of Manitoba ◽  
The University ◽  
High Resolution Mass Spectrometer ◽  
Resolution Mass

The 1.00-m radius, high resolution mass spectrometer at the University of Manitoba has been used to determine the spacings of a series of mass spectral doublets. These give improved values for the mass differences between the stable nuclides in Tl, Pb, and Bi and relate these values to previous atomic masses and mass differences for the isotopes of Hg. A least-squares adjustment has been performed on all available atomic mass data (including the mass spectroscopic results from this laboratory) for the region 78 ≤ Z ≤ 84.

scholarly journals Using Least-Squares Residuals to Assess the Stochasticity of Measurements—Example: Terrestrial Laser Scanner and Surface Modeling

2021 ◽  
Vol 5 (1) ◽  
pp. 59
Author(s):  
Gaël Kermarrec ◽  
Niklas Schild ◽  
Jan Hartmann
Keyword(s):  
Least Squares ◽  
Laser Scanner ◽  
Real Data ◽  
Point Clouds ◽  
Statistical Testing ◽  
Normal Vector ◽  
Engineering Structures ◽  
3D Point Clouds ◽  
Least Squares Adjustment ◽  
Correlation Parameters

Terrestrial laser scanners (TLS) capture a large number of 3D points rapidly, with high precision and spatial resolution. These scanners are used for applications as diverse as modeling architectural or engineering structures, but also high-resolution mapping of terrain. The noise of the observations cannot be assumed to be strictly corresponding to white noise: besides being heteroscedastic, correlations between observations are likely to appear due to the high scanning rate. Unfortunately, if the variance can sometimes be modeled based on physical or empirical considerations, the latter are more often neglected. Trustworthy knowledge is, however, mandatory to avoid the overestimation of the precision of the point cloud and, potentially, the non-detection of deformation between scans recorded at different epochs using statistical testing strategies. The TLS point clouds can be approximated with parametric surfaces, such as planes, using the Gauss–Helmert model, or the newly introduced T-splines surfaces. In both cases, the goal is to minimize the squared distance between the observations and the approximated surfaces in order to estimate parameters, such as normal vector or control points. In this contribution, we will show how the residuals of the surface approximation can be used to derive the correlation structure of the noise of the observations. We will estimate the correlation parameters using the Whittle maximum likelihood and use comparable simulations and real data to validate our methodology. Using the least-squares adjustment as a “filter of the geometry” paves the way for the determination of a correlation model for many sensors recording 3D point clouds.

scholarly journals The isotopic constitution and atomic weights of hafnium, thorium, rhodium, titanium, zirconium, calcium, gallium, silver, carbon, nickel, cadmium, iron and indium

1935 ◽  
Vol 149 (867) ◽  
pp. 396-405 ◽  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Rare Earths ◽  
Mass Spectra ◽  
Mass Number ◽  
Atomic Weight ◽  
Complete Data ◽  
Pure Sample ◽  
Titanium Zirconium ◽  
Similar Element

An account of experiments has already been given by which the analyses of the rare earth elements were completed with the aid of a particularly favourable arrangement of the anode ray apparatus. This paper contains a description of analyses of other elements made with the same setting and also of some others subsequently made to obtain more accurate and complete data on elements whose constitution had already been provisionally settled. Results (72) Hafnium —Many previous attempts to obtain the mass spectra of this element had failed. For the most similar element, zirconium, the only successful results had been obtained from the fluoride. A pure sample of hafnium fluoride had been kindly provided by Professor G. v. Hevesy, one of the discoverers of the element, and this was incorporated into the anode mixture. The first trial was a failure; but after the work on zirconium described below a second attempt was made, this time with resolved, so that only rough estimates of abundance could be obtained. These were as follows:— Mass numbers . . . . . 176 177 178 179 180 % abundance . . . . . . 5 19 28 18 30 These given a mean mass number 178·5. Applying the same correction as with the rare earths we get atomic weight of hafnium = 178·4 ± 0·2 in fair agreement with the International value 178·6.

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