A new method of producing an electric quadrupole field

In contrast to the canonically conjugate variates q, p representing the position and momentum of a particle in the phase space distributions, the three Cartesian components, Jx, Jy, Jz of a spin-j system constitute the mutually non-commuting variates in the quasi-probabilistic spin distributions. It can be shown that a univariate spin distribution is never squeezed and one needs to look into either bivariate or trivariate distributions for signatures of squeezing. Several such distributions result if one considers different characteristic functions or moments based on various correspondence rules. As an example, discrete probability distribution for an arbitrary spin-1 assembly is constructed using Wigner-Weyl and Margenau-Hill correspondence rules. It is also shown that a trivariate spin-1 assembly resulting from the exposure of nucleus with non-zero quadrupole moment to combined electric quadrupole field and dipole magnetic field exhibits squeezing in certain cases.

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A NEW METHOD TO MEASURE THE ELECTROMAGNETIC PROPERTY OF THE W BOSON IN e+e− COLLISIONS

International Journal of Modern Physics A ◽

10.1142/s0217751x92001460 ◽

1992 ◽

Vol 07 (14) ◽

pp. 3291-3310 ◽

Cited By ~ 1

Author(s):

HIROTOMO IWASAKI

Keyword(s):

W Boson ◽

Event Rate ◽

Electromagnetic Property ◽

Electric Quadrupole ◽

Systematic Errors ◽

New Method ◽

Quadrupole Moments ◽

Energy Distributions ◽

Background Elimination ◽

Magnetic Quadrupole

With the effective WW γ couplings incorporating the magnetic dipole, electric dipole, magnetic quadrupole and electric quadrupole moments of the W boson, the cross-section of e+e− → e±νe W ∓ is evaluated exactly and its sensitivity to these moments is investigated. The background elimination is discussed for the measurement of the WW γ couplings, and the resulting event rate of the single-W production is evaluated at [Formula: see text] and 500 GeV. Also, a new method for the precision measurement of the WW γ coupling is proposed: it utilizes the distinction of the W boson energy distributions of the annihilation and nonannihilation contributions and reduces the systematic errors.

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New method for the determination of the sign and magnitude of electric quadrupole splittings. II. The electric field gradient of Co in hcp and fcc Co

Physical Review B ◽

10.1103/physrevb.25.1529 ◽

1982 ◽

Vol 25 (3) ◽

pp. 1529-1534 ◽

Cited By ~ 19

Author(s):

E. Hagn ◽

E. Zech

Keyword(s):

Electric Field ◽

Electric Field Gradient ◽

Field Gradient ◽

Electric Quadrupole ◽

New Method

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Mass-selective removal of ions from Paul traps using parametric excitation

Applied Physics B ◽

10.1007/s00340-020-07491-8 ◽

2020 ◽

Vol 126 (11) ◽

Author(s):

Julian Schmidt ◽

Daniel Hönig ◽

Pascal Weckesser ◽

Fabian Thielemann ◽

Tobias Schaetz ◽

...

Keyword(s):

Parametric Excitation ◽

Ion Trap ◽

Paul Trap ◽

Electric Quadrupole ◽

Linear Increase ◽

Selective Removal ◽

Ion Trapping ◽

Secular Frequency ◽

Quadrupole Field ◽

Narrow Bandwidth

AbstractWe study a method for mass-selective removal of ions from a Paul trap by parametric excitation. This can be achieved by applying an oscillating electric quadrupole field at twice the secular frequency $$\omega _{\text {sec}}$$ ω sec using pairs of opposing electrodes. While excitation near the resonance with the secular frequency $$\omega _{\text {sec}}$$ ω sec only leads to a linear increase of the amplitude with excitation duration, parametric excitation near $$2\, \omega _{\text {sec}}$$ 2 ω sec results in an exponential increase of the amplitude. This enables efficient removal of ions from the trap with modest excitation voltages and narrow bandwidth, therefore, substantially reducing the disturbance of ions with other charge-to-mass ratios. We numerically study and compare the mass selectivity of the two methods. In addition, we experimentally show that the barium isotopes with 136 and 137 nucleons can be removed from small ion crystals and ejected out of the trap while keeping $$^{138}\text {Ba}^{+}$$ 138 Ba + ions Doppler cooled, corresponding to a mass selectivity of better than $$\Delta m / m = 1/138$$ Δ m / m = 1 / 138 . This method can be widely applied to ion trapping experiments without major modifications since it only requires modulating the potential of the ion trap.

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A Magnetic Spectrometer for a Scanning Transmission Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052195 ◽

1974 ◽

Vol 32 ◽

pp. 436-437

Author(s):

A. Kosiara ◽

J. W. Wiggins ◽

M. Beer

Keyword(s):

Scanning Transmission Electron Microscope ◽

Magnetic Spectrometer ◽

Fringe Field ◽

Curvature Radius ◽

Magnetic Pole ◽

Quadrupole Field ◽

Transmission Electron ◽

Scanning Transmission ◽

Under Construction ◽

Image Position

A magnetic spectrometer to be attached to the Johns Hopkins S. T. E. M. is under construction. Its main purpose will be to investigate electron interactions with biological molecules in the energy range of 40 KeV to 100 KeV. The spectrometer is of the type described by Kerwin and by Crewe Its magnetic pole boundary is given by the equationwhere R is the electron curvature radius. In our case, R = 15 cm. The electron beam will be deflected by an angle of 90°. The distance between the electron source and the pole boundary will be 30 cm. A linear fringe field will be generated by a quadrupole field arrangement. This is accomplished by a grounded mirror plate and a 45° taper of the magnetic pole.

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Selective Sampling and Orientation of Non-Homogeneous Tissues

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100238 ◽

1968 ◽

Vol 26 ◽

pp. 98-99

Author(s):

C. C. Clawson ◽

L. W. Anderson ◽

R. A. Good

Keyword(s):

Electron Microscopy ◽

Electron Microscope ◽

Light Microscopy ◽

Random Sampling ◽

New Method ◽

Microscope Examination ◽

Small Areas ◽

Selective Sampling ◽

Large Numbers ◽

Specific Orientation

Investigations which require electron microscope examination of a few specific areas of non-homogeneous tissues make random sampling of small blocks an inefficient and unrewarding procedure. Therefore, several investigators have devised methods which allow obtaining sample blocks for electron microscopy from region of tissue previously identified by light microscopy of present here techniques which make possible: 1) sampling tissue for electron microscopy from selected areas previously identified by light microscopy of relatively large pieces of tissue; 2) dehydration and embedding large numbers of individually identified blocks while keeping each one separate; 3) a new method of maintaining specific orientation of blocks during embedding; 4) special light microscopic staining or fluorescent procedures and electron microscopy on immediately adjacent small areas of tissue.

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