_{1}

^{*}

After one century of nuclear physics, the anomalous Rutherford scattering remains a puzzle: its underlying fundamental laws are still missing. The only presently recognized electromagnetic interaction in a nucleus is the so-called Coulomb electric force, in 1/
r, only positive thus repulsive in official nuclear physics, explaining the Rutherford scattering at low kinetic energy of the impacting alpha particles. At high kinetic energy the Rutherford scattering formula doesn’t work, thus called “anomalous scattering”. I have discovered that, to solve the problem, it needs only to replace, at high kinetic energy, the Coulomb repulsive electric potential in 1/
r, by the also repulsive magnetic Poisson potential in 1/
r
^{3}. In log-log coordinates, one observes two straight lines of slopes, respectively −2 and −6. They correspond with the −1 and −3 exponents of the only repulsive electric and magnetic interactions, multiplied by 2 due to the cross-sections. Both Rutherford (normal and anomalous) scattering have been calculated electromagnetically. No attractive force needed.

Rutherford explained the low energy scattering, electric. At high energies, a singularity appears, followed by a steeper slope, called anomalous Rutherford scattering. During one century, it remained a puzzle due to the wrong assumption of inadequacy of classical forces [

Alpha particles, from a radioactive source, striking a thin gold foil produce a tiny, but visible flash of light when they strike a fluorescent screen (

Rutherford explained why some alpha particles projected on an atom were reflected by a small nucleus: “Assuming classical trajectories for the scattered alpha particles, Coulomb’s law was found to hold for encounters between alpha particles and nuclei” [

The purpose of this paper is to solve the unsolved problem of the so-called anomalous scattering of α particles.

Rutherford discovered that the impacting electrically charged α particles are deviated by the repulsive electrostatic force of the impacted nuclei. The origin of the concept of strong force comes from the observation of the discrepancy between Rutherford theory and experiment at high kinetic energies (

At high kinetic energies, Geiger observed that the deviation was larger than predicted by the electric force, repulsive [

protons and an atomic nucleus with a number Z of protons, e is the elementary electric charge,

lomb’s constant. The first term of the Equation (1) corresponds to the “normal” electric Rutherford scattering

and the second term to the “anomalous” scattering, magnetic if n = 3. The sign of B [

The sign of a, not specified, seems to be positive. The α particles having no magnetic moment, no magnetic interaction between them seems should be possible. Nevertheless, when the kinetic energy becomes larger than the binding energy (absolute value), the freed nucleons get kinetic energy and magnetic moments. Nuclear scattering became thus entirely and only electromagnetic. Unfortunately, with the wrong attractive negative sign of the magnetic potential, Bieler was unable to solve the problem although the solution was simply to replace the wrong attractive negative sign of Equation (2) by a repulsive positive sign:

This electromagnetic formula works fine, as shown on ^{3} potential increases and dominates the electric potential, becoming the main component of the potential. Sexl [

The differential cross-section

The Rutherford formula may be simplified for given θ, z and Z:

The exponent −2, due to the electrostatic interaction cross-section, becomes, logarithmically, the coefficient −2:

where C_{e} is to be adjusted to the singularity, near to the α particle binding energy, _{e} is replaced by C_{m}:

The variables are the differential cross section _{0} of the initial α particle. C_{e} and C_{m} are

adjusted to make coincide the intersection between the electric and magnetic straight lines with the Rutherford singularity. At the singularity, the initial kinetic energy is more or less lower than the absolute value of the α particle total binding energy, ^{4}He binding energy, taken positive.

The kinetic energy at the Rutherford singularity is a little less than the experimental value of the total binding energy of the α particle,

According to [

The magnetic interaction between nucleons is ignored in “conventional” nuclear physics. The ^{4}He also called α particle has no apparent magnetic moment. When the kinetic energy is high enough to destroy the ^{4}He, the magnetic moments of protons and of neutrons reappear. The magnetic potential being in 1/r^{3}, the slope of the curve (

At short r, the repulsive magnetic potential in r^{−}^{3} overcomes the also repulsive electric potential in r^{−}^{1}. No need of an attractive wrong “strong force”. No need also of quantum mechanics and/or relativity, at least for kinetic energies between 10 and 50 MeV.

One century ago, Rutherford discovered the electric part of the nuclear scattering. In order to explain the discrepancy at high energy, Chadwick hypothesized a new type of force, strong and attractive. Bieler assumed a magnetic strong force, also attractive, with exponent +6 instead of −6, thus missing the discovery [

The Rutherford scattering is electric at low kinetic energy and magnetic at high kinetic energy of the impacting α particles. Nuclear scattering and binding energy [

Thanks to persons at Dubna for their interest to my electromagnetic theory of the nuclear energy. The first question was about scattering. I said I don’t know. Now I know: the anomalous Rutherford scattering is magnetic. The second question was: “The strong force doesn’t exist?” and a third one about orbiting nucleons.

Bernard Schaeffer, (2016) Anomalous Rutherford Scattering Solved Magnetically. World Journal of Nuclear Science and Technology,06,96-102. doi: 10.4236/wjnst.2016.62010