Charge Spectrometer Research Articles

A Specific Use of TOHOKU Charge Spectrometer as a Cascade-Type Mass Spectrometer

A Specific Use of TOHOKU Charge Spectrometer as a Cascade-Type Mass Spectrometer

Characterization and Discussion of Charge Spectrometer by Means of Ion Beam Experiment

Characterization and Discussion of Charge Spectrometer by Means of Ion Beam Experiment

Charge distribution on polystyrene aerosols and deposition in the human nose

A method is described for measuring the charge distribution on monodisperse polystyrene aerosol particles, using a parallel-plate charge spectrometer. Data are presented on the magnitude of the charges carried by aerosol particles produced by atomization of a suspension of the particles in alcohol, and on the residual charges after attempted equilibration by mixing with a bipolar atmosphere produced by krypton-85 sources. The measured values of charge, after charge reduction, are compared with those predicted by the Boltzmann distribution of charge. The reduction in charge had no significant effect upon deposition of the particles in the nasopharyngeal region of the human repiratory tract.

Specific Features of Tohoku Charge Spectrometer

This report describes the specific features of the Tohoku Charge Spectrometer(TOHOKU CS)which has been constructed for the study of chemical effects of the nuclear transformations in gases, especially of the charge distribution of the residual atoms and of ion-molecule reactions in order to elucidate the primary and elemental stages in hot-atom chemistry. The facility is available for a chargespectrometer with a large source volume and a double mass spectrometer connected in perpendicular. Ions can be produced by the electron impact, X-ray irradiation or nuclear decay processes in the source volume. Charge spectrum of the residual atom after the Auger process of the nuclear decay can be measured through the first stage mass spectrometer, and products of ion-molecule reactions in the reaction chamber can be separated through the second mass spectrometer and detected by an aid of a16stages Cu-Be electron multiplier. Pulse countings are applicable in the both cases as well as direct current recordings to estimate the charged atoms or the fragment distribution. The specific availabilities of this facility are shown in some typical results by the preliminary experiments.

Double Electron Ejection Resulting from Photo-Ionization in the Outermost Shell of He, Ne, and Ar, and Its Relationship to Electron Correlation

The probability of ejecting two or more electrons by the interaction of an x ray with the outermost shell of He, Ne, and Ar has been investigated. The relative abundances of doubly charged to singly charged ions following x irradiation have been measured with a charge spectrometer. These ratios are essentially constant over the range of x-ray energies from 3 to 8 times the threshold for double ionization. They are, respectively, 0.035, 0.14, and 0.17 for He, Ne, and Ar. Energy spectra for electrons ejected in photo-ionization have been measured with an electron spectrometer. In addition to characteristic photolines, continuum spectra are found, which are related to double electron ejection. The probabilities for double electron ejection as determined from these spectra are in agreement with those obtained by charge spectrometry. The shapes of the continuum spectra are qualitatively similar to those expected for electron shake-off. However, the probabilities for electron shake-off as calculated from single-electron wave functions are much smaller than found experimentally. It is suggested that a many-body solution which explicitly includes electron correlations may be necessary. For example, such a calculation by Salpeter and Zaidi, for the case where one electron goes to the continuum while the other goes to the $2s$ state in the photo-ionization of He, is shown to be in good agreement with experiment. Some results are also presented on the differential cross sections of Ne and Ar for C $K\ensuremath{\alpha}$ x rays.

荷電分光計による蚊取線香煙霧の荷電測定

The modified charge spectrometer was designed and constructed, and the apparatus was used for the measurements of charge of mosquite incense aerosol, which was charged by corona discharging. The results for test were successful. The charge was calculated from the results by using several different apprroaches, whose methods were given by Lipscomb, Johnstone, Bonssinesq and the authors. On the other hand, the charge taken by aerosol was theoretically obtained on the assumption that the charging of aerosol was done by combined mechanism of ionic diffusion and bombardment. The theoretical values agreed well with the experimental value calculated by Johnstone's approache. The results showed that the sign of the charge of the aerosol was positive at the condition of positive corona. It was found that the corona discharge voltage decreased from the regular value to a lower value in the presence of aerosol.