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Detecting Neutrinos

7 Solar Neutrino Problem

This is section 7 of 13.

This is a complicated issue requiring an understanding of both the Sun and neutrinos.

The problem is measurements don't match predictions.

An analysis of both is required to solve the problem.

7.1 The problem

Here is its description.

The solar neutrino problem concerned a large discrepancy between the flux of solar neutrinos as predicted from the Sun's luminosity and as measured directly. The discrepancy was first observed in the mid-1960s and was resolved around 2002.

The flux of neutrinos at Earth is several tens of billions per square centimetre per second, mostly from the Sun's core. They are nevertheless hard to detect, because they interact very weakly with matter, traversing the whole Earth as light does a thin layer of air. Of the three types (flavors) of neutrinos known in the Standard Model of particle physics, the Sun produces only electron neutrinos. When neutrino detectors became sensitive enough to measure the flow of electron neutrinos from the Sun, the number detected was much lower than predicted. In various experiments, the number deficit was between one half and two thirds.

Particle physicists knew that a mechanism, discussed back in 1957 by Bruno Pontecorvo, could explain the deficit in electron neutrinos. However, they hesitated to accept it for various reasons, including the fact that it required a modification of the accepted Standard Model. They first pointed at the solar model for adjustment, which was ruled out. Today it is accepted that the neutrinos produced in the Sun are not massless particles as predicted by the Standard Model but rather mixed quantum states made up of defined-mass eigenstates in different (complex) proportions. That allows a neutrino produced as a pure electron neutrino to change during propagation into a mixture of electron, muon and tau neutrinos, with a reduced probability of being detected by a detector sensitive to only electron neutrinos.

Several neutrino detectors aiming at different flavors, energies, and traveled distance contributed to our present knowledge of neutrinos. In 2002 and 2015, a total of four researchers related to some of these detectors were awarded the Nobel Prize in Physics.


Here is part of the 2002 Nobel Prize in Physics award description.

The Earth lies in the path of a continuous flux of cosmic particles and other types of radiation. This year's Nobel Laureates in Physics have used these very smallest components of the universe to increase our understanding of the very largest: the Sun, stars, galaxies and supernovae. The new knowledge has changed the way we look upon the universe.

The mysterious particle called a neutrino was predicted as early as 1930 by Wolfgang Pauli (Nobel Prize in 1945), but it would take 25 years to prove its existence (by Frederick Reines, Nobel Prize in 1995). This is because neutrinos, which are formed in the fusion processes in the Sun and other stars when hydrogen is converted into helium, hardly interact at all with matter and are therefore very difficult to detect. For example, thousands of billions of neutrinos pass through us every second without our noticing them. Raymond Davis Jr constructed a completely new detector, a gigantic tank filled with 600 tonnes of fluid, which was placed in a mine. Over a period of 30 years he succeeded in capturing a total of 2,000 neutrinos from the Sun and was thus able to prove that fusion provided the energy from the Sun. With another gigantic detector, called Kamiokande, a group of researchers led by Masatoshi Koshiba was able to confirm Davis's results. They were also able, on 23 February 1987, to detect neutrinos from a distant supernova explosion. They captured twelve of the total of 10^16 neutrinos (10,000,000,000,000,000) that passed through the detector. The work of Davis and Koshiba has led to unexpected discoveries and a new, intensive field of research, neutrino-astronomy.



First, the Sun must be described, which is assumed to be the source of specific eutron types and counts.

Second, the method of detecting and classifying these neutrinos is described.

The HOMESTAKE experiment was the basis of the 2002 Nobel Prize.

Both HOMESTAKE and the Reines experiments are described in section Neutrino Detectors

7.2 The Sun

Our Sun is not a sphere of gaseous plasma which is consuming itself by a process of fusing atoms deep in its core to create heavier elements and to create an immense amount of energy to be radiated from the surface.

7.2.1 Solar Model

Dr. Pierre-Marie Robitaille developed a solar model which explains all solar observations.

He has a YouTube channel, Sky Scholar with many videos on many topics of physics and cosmology.

His first, and most important paper was titled:

Forty Lines of Evidence for Condensed Matter - The Sun on Trial: Liquid Metallic Hydrogen as a Solar Building Block

This excerpt is from its conclusion.

Collectively,these lines of evidence provide a systematic challenge to the gaseous models of the Sun
and expose the many hurdles faced by modern approaches. Observational astronomy
and laboratory physics have remained unable to properly justify claims that the solar
body must be gaseous. At the same time, clear signs of condensed matter interspersed
with gaseous plasma in the chromosphere and corona have been regrettably dismissed.
As such, it is hoped that this exposition will serve as an invitation to consider condensed
matter, especially metallic hydrogen, when pondering the phase of the Sun.

That paper and others are available through 1 web page via the reference link.


7.2.2 Creating the Elements

The SAFIRE project duplicated in a laboratory conditions on the solar surface.

The experiment which began with only hydrogen in the chamber resulted in several elements being found on the anode sphere. These elements were created during the experiment.
The chamber had a second sphere as the cathode in this circuit creating  a charge differential, to cause transmutation.


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last change 04/03/2022