Conveners
Why and How the Sun and the Stars Shine: the Borexino Experiment: Block 1
- Dmitry Naumov (JINR)
- Gianpaolo Bellini (University of Milano and INFN)
Why and How the Sun and the Stars Shine: the Borexino Experiment: Block 2
- Gianpaolo Bellini (University of Milano and INFN)
- Gemma Testera (INFN Genova (Italy))
Why and How the Sun and the Stars Shine: the Borexino Experiment: Block 3
- Gianpaolo Bellini (University of Milano and INFN)
- Gioacchino Ranucci (Istituto Nazionale di Fisica Nucleare - sezione di Milano)
Description
The Borexino experiment, thanks to the unprecedented radiopurity of the detector, never reached even now by any other experiment, succeeded to measure all solar neutrinos fluxes, which are emitted by five nuclear reactions of the pp cycle, which produces 99% the whole solar energy, and from the CNO cycle, responsible for 1% of it. The existence of these cycles had already been hypothesized since 1937 by Hans Bethe and Carl Friedrich von Weizsacker: the pp cycle, which leads to the production of 4He, is dominant in stars having a size like or smaller than the Sun, while the CNO cycle, catalyzed by 12C, 14N and 16O nuclides, dominates in massive stars, with a mass greater at least 30% more that the solar one. The solar neutrinos flux has been globally measured by radiochemical experiments, without distinguishing among the contributions of the various nuclear reactions, while the experiments with Cherenkov light studied only a tail of the 8B reaction corresponding to 0.1% of the total flux; on the other hand, the CNO cycle has never received direct proof of its existence.
Due to its very high radiopurity, the Borexino experiment was able to measure separately the fluxes of the pp five reactions that emit neutrinos, attesting their identification, and reached the first experimental evidence of the CNO cycle existence. In this Session, these results will be discussed together with the upgrading of neutrino oscillation physics as a consequence of the measurements described above; in addition what discovered so far on geo-neutrinos has been presented.
About 99 percent of solar energy is produced through sequences of nuclear processes that convert hydrogen into helium in the so-called pp-chain. The neutrinos emitted in five of these reactions represent a unique probe of the Sun’s internal working and, at the same time, offer an intense natural neutrino beam for fundamental physics research.
The Borexino experiment consists of a large-volume...
Solar neutrinos provide a sample of electron neutrinos of different energies. They are therefore a unique probe of the electron neutrino propagation through solar matter and for the experimental study of the MSW effect. Borexino, with its unique purity and sensitivity, has been able to study individually all components, extracting the best test of electron neutrino survival probability to...
Borexino recently detect solar neutrinos from the CNO cycle.
In the talk I will review the experiment, the analysis method, the CNO result and its implications.
The detection of neutrinos produced by pp-chain and CNO-cycle provide us fundamental informations on the thermal stratification and on the chemical composition of the solar core.
These can be used to verify the predictions ot the so-called Standard Solar Models (SSMs), which represent a benchmark for stellar evolution, and to constrain standard and non/standard energy generation and...
The CNO cycle consists of a series of nuclear reactions that provide energy in stars. There exist multiple different cycles depending on temperature and relative abundance of elements in stars. In the Sun the CNO cycle is a catalyst cycle where nuclear reactions cycle through carbon, nitrogen and oxygen. Initially, a free proton fuses with a carbon-12 nucleus starting a sequence of reactions...
Geoneutrino observation is reviewed.
The latest data of KamLAND and Borexino are included as well as the prospects of
near future experiments.
Astrophysical neutrinos cover at least 18 orders of magnitude in energy, starting from meV (relic neutrinos) till PeV, the highest energy neutrinos ever detected as of today. Among the possible extraterrestrial sources of antineutrinos are the supernovae explosions, gamma ray bursts, neutron and black hole mergers and solar flares. In the Sun, the conversion of solar neutrinos into...
Borexino, a large volume detector for low energy neutrino spectroscopy, is currently taking data underground since 2007 at the Laboratori Nazionali del Gran Sasso, Italy. The main goal of the experiment is the real-time measurement of solar neutrinos, especially the low energy part of the spectrum. Neutrinos are detected via neutrino-electron scattering in an ultra-pure organic liquid...
About 99 percent of solar energy is produced through sequences of nuclear processes that convert hydrogen into helium in the so-called pp-chain. The neutrinos emitted in five of these reactions represent a unique probe of the Sun’s internal working and, at the same time, offer an intense natural neutrino beam for fundamental physics research.
The Borexino experiment consists of a large-volume...
Solar neutrinos provide a sample of electron neutrinos of different energies. They are therefore a unique probe of the electron neutrino propagation through solar matter and for the experimental study of the MSW effect. Borexino, with its unique purity and sensitivity, has been able to study individually all components, extracting the best test of electron neutrino survival probability to...
Stars are fueled by nuclear reactions occurring in their core. In massive stars (approximately 1.3 more massive than our Sun) the dominant reactions are believed to be those belonging to the so-called CNO cycle, while in lighter stars (including our Sun) the proton-proton chain prevails. Until now, we had no direct experimental evidence of the existence of the CNO cycle.
Recently, the...
The detection of neutrinos produced by pp-chain and CNO-cycle provide us fundamental informations on the thermal stratification and on the chemical composition of the solar core.
These can be used to verify the predictions ot the so-called Standard Solar Models (SSMs), which represent a benchmark for stellar evolution, and to constrain standard and non/standard energy generation and...
The CNO cycle consists of a series of nuclear reactions that provide energy in stars. There exist multiple different cycles depending on temperature and relative abundance of elements in stars. In the Sun the CNO cycle is a catalyst cycle where nuclear reactions cycle through carbon, nitrogen and oxygen. Initially, a free proton fuses with a carbon-12 nucleus starting a sequence of reactions...
The largest amount of antineutrinos detected about the Earth is emitted by the natural radioactive decays inside the Earth: more than 99% of the present-day Earth’s radiogenic heat is originated by the β$^{-}$ decays of $^{40}$K and of $^{232}$Th and $^{238}$U chains isotopes. Other flux components are provided by cosmic rays interactions in the atmosphere or by possible extra-terrestrial...
Borexino, a large volume detector for low energy neutrino spectroscopy, is currently taking data underground since 2007 at the Laboratori Nazionali del Gran Sasso, Italy. The main goal of the experiment is the real-time measurement of solar neutrinos, especially the low energy part of the spectrum. Neutrinos are detected via neutrino-electron scattering in an ultra-pure organic liquid...
About 99 percent of solar energy is produced through sequences of nuclear processes that convert hydrogen into helium in the so-called pp-chain. The neutrinos emitted in five of these reactions represent a unique probe of the Sun’s internal working and, at the same time, offer an intense natural neutrino beam for fundamental physics research.
The Borexino experiment consists of a large-volume...
Solar neutrinos provide a sample of electron neutrinos of different energies. They are therefore a unique probe of the electron neutrino propagation through solar matter and for the experimental study of the MSW effect. Borexino, with its unique purity and sensitivity, has been able to study individually all components, extracting the best test of electron neutrino survival probability to...
The Borexino has recently reported the first experimental evidence of neutrinos from the CNO cycle. Since this process accounts only for about 1% of the total energy production in the Sun, the associated neutrino flux, is extremely low as compared with the one from the pp-chain, the dominant process of hydrogen burning.
This experimental evidence of the CNO neutrinos was obtained using the...
The detection of neutrinos produced by pp-chain and CNO-cycle provide us fundamental informations on the thermal stratification and on the chemical composition of the solar core.
These can be used to verify the predictions ot the so-called Standard Solar Models (SSMs), which represent a benchmark for stellar evolution, and to constrain standard and non/standard energy generation and...
The CNO cycle consists of a series of nuclear reactions that provide energy in stars. There exist multiple different cycles depending on temperature and relative abundance of elements in stars. In the Sun the CNO cycle is a catalyst cycle where nuclear reactions cycle through carbon, nitrogen and oxygen. Initially, a free proton fuses with a carbon-12 nucleus starting a sequence of reactions...
The largest amount of antineutrinos detected about the Earth is emitted by the natural radioactive decays inside the Earth: more than 99% of the present-day Earth’s radiogenic heat is originated by the β$^{-}$ decays of $^{40}$K and of $^{232}$Th and $^{238}$U chains isotopes. Other flux components are provided by cosmic rays interactions in the atmosphere or by possible extra-terrestrial...
