Abstract The kernel ridge regression (KRR) method with a Gaussian is used to improve the description of nuclear charge radius by several phenomenological formulae. widely , N^{1/3} and Z^{1/3} formulae, their improved versions including isospin dependence, are adopted as examples. parameters in these six formulae refitted using Levenberg–Marquardt method, which give better...

1. It has been shown in preceding papers that when we separate solutions of electrolytes from pure water by collodion membranes the ions with the same sign of charge as the membrane increase while the ions with the opposite sign of charge diminish the rate of diffusion of water from the side of pure water to the side of solution; and that the accelerating and depressing effects of these ions on...

in this study, an electrostatic sprayer which had been previously designed and constructed was evaluated in order to quantify the charging of droplets. liquid atomization was achieved by using an ultrasonic nozzle. the nozzle maximum flow rate was 25 milliliters per minute and vibration frequency was about 30 khz. the induction method was used for charging the output droplets. all experiments w...

We propose to perform a high precision e − p elastic cross sections measurement at very low four-momentum transfer squared, Q, from 10−4 to 10−2 (GeV/c) range using a high resolution calorimeter. The absolute value of the e−p cross sections will be controlled by a well known QED process, the Møller scattering, which will be continuously measured in this experiment within similar kinematics and ...

A new formula for the nuclear charge radius is proposed, dependent on the mass number A and neutron excess N−Z in the nucleus. It is simple and it reproduces all the experimentally available mean square radii and their isotopic shifts of even–even nuclei much better than other frequently used relations. PACS: 21.10.Dr, 21.60.Ev ∗This work is partly supported by the Polish Committee of Scientifi...

The Σ− mean squared charge radius has been measured in the space-like Q range 0.035–0.105 GeV/c by elastic scattering of a Σ− beam off atomic electrons. The measurement was performed with the SELEX (E781) spectrometer using the Fermilab hyperon beam at a mean energy of 610 GeV/c. We obtain 〈r2 ch〉Σ− = (0.61 ± 0.12 (stat.) ± 0.09 (syst.)) fm. The proton and π− charge radii were measured as well ...

We have performed precision laser spectroscopy on individual 6He (t(1/2)=0.8 s) atoms confined and cooled in a magneto-optical trap, and measured the isotope shift between 6He and 4He to be 43 194.772+/-0.056 MHz for the 2(3)S1-3(3)P2 transition. Based on this measurement and atomic theory, the nuclear charge radius of 6He is determined for the first time in a method independent of nuclear mode...

A phenomenological Dyson-Schwinger equation approach to QCD, formalised in terms of a QCD based model field theory, is used to calculate the electromagnetic charge radius of the pion. The contributions from the quark core and pion loop, as defined in this approach, are identified and compared. It is shown explicitly that the divergence of the charge radius in the chiral limit is due to the pion...

For nearly forty years, the Galster parametrization has been employed to fit existing data for the neutron electric form factor, GnE, vs the square of the four-momentum transfer, Q 2. Typically this parametrization is constrained to be consistent with experimental data for the neutron charge radius. However, we find that the Galster form does not have sufficient freedom to accommodate reasonabl...

We revisit the problem of the kink in the charge radius shift of neutron-rich even isotopes near the N=126 shell closure. We show that the ability of a Skyrme force to reproduce the isotope shift is determined by the occupation of the neutron 1i(11/2) orbital beyond N=126 and the corresponding change it causes to deeply-bound protons orbitals with a principal quantum number of 1. Given the obse...