History of Solar Neutrino Observations

 This work is a nice review encompassing all the historical decisions in the solar neutrino regime.  It initiates the breakthrough journey from the Kamiokande detector which actually was instilled to observe proton decay, while later on shifting on detecting the solar neutrinos. This paper talks of the necessary amendments needed in the detector for observing low energy events. Moving on further in the work it talks of GALLEX and SAGE experiment as well. While talking of these three historic experiments one cannot leave the discussion on the solar neutrino problem that arose owing to these experiments' detection of 𝜈e from the Sun. This solar neutrino problem led to the need of confirming solar neutrino oscillation independent of the Standard Solar Model. For certifying model-independent neutrino oscillation, the focus shifted towards the shape of the energy spectrum and the time variation of solar neutrino event rates. This necessitated an update in Kamiokande, thus leading to Super-Kamiokande and also the SNO experiment. The figure below is from the paper we are discussing which gives the contour region in the 𝜈e and 𝜈𝛍 / 𝛕 plane from the recent results of Super-K and SNO, while each band gives the 1𝛔 relative precision around each measurement.