nuclear fusioin

50 %
50 %
Information about nuclear fusioin
Entertainment

Published on December 4, 2007

Author: miloung

Source: authorstream.com

How an Underground Observatory Verified that Stars Shine by Nuclear Fusion and Suggested that Neutrinos May Oscillate:  How an Underground Observatory Verified that Stars Shine by Nuclear Fusion and Suggested that Neutrinos May Oscillate John Bahcall Institute for Advanced Study Princeton University Early Participants:  Early Participants Early participants: Shortly after the proposal by Davis and Bahcall in 1964 that a 37Cl solar neutrino experiment was feasible, three of the people most involved were photographed in front of a small version of the chlorine tank. From right to left, they are: Raymond Davis, Jr., John Bahcall, and Don Harmer. (The photograph, courtesy of Raymond Davis, Jr., Appeared in Mercury, March/April 1990.) The Inspection:  The Inspection Davis and Bahcall inspect the solar neutrino detector: Ray Davis (circa 1966) shows John Bahcall the tank containing 100,000 gallons of perchloroethylene, a neutrino observatory made of cleaning fluid. The picture was taken in the Homestake mine, shortly before the experiment began operating. The photograph is reproduced from J. N. Bahcall, “Solar Neutrinos,” Proc. 2nd Int. Conference on High-Energy Physics and Nuclear Structure, 1967, pp. 232-255, ed. G. Alexander (North Holland, Amsterdam). Nuclear Reaction Energy Budget:  Nuclear Reaction Energy Budget Nuclear burning: The budget for the generic nuclear reaction that accounts for energy generation among main sequence stars consists of the burning of four protons to give an alpha particle, two positrons, and two neutrinos. Neutrino Oscillations are the Favored Solution for Explaining the Solar Neutrino Problems:  Neutrino Oscillations are the Favored Solution for Explaining the Solar Neutrino Problems Neutrino oscillations in matter: The figure shows the regions in MSW parameter space that are consistent with the total rates observed in the four solar neutrino experiments (chlorine, Super-Kamiokande, GALLEX, and SAGE) and with the electron recoil energy spectrum and zenith angle distribution that are measured by Super-Kamiokande. The hep neutrino flux is allowed to vary freely. Contours are drawn at both 95% C.L. and 99% C.L. [Phys. Rev. D, 58, 096016-2 - 096016-22 (1998), hep-ph/9807216.] Neutrino Oscillations in Vacuum:  Neutrino Oscillations in Vacuum The figure shows the allowed parameter region for vacuum oscillations that is consistent with the measured total rates, the recoil electron energy spectrum, and the Day-Night asymmetry. Contours are drawn at 99% C.L. [Ref. Phys. Rev. D, 58, 096016-2 - 096016-22 (1998), hep-ph/9807216. ] Solar Neutrino Energy Spectrum:  Solar Neutrino Energy Spectrum The energy Spectrum of neutrinos from the pp chain of interactions in the Sun, as predicted by the standard solar model. Neutrino fluxes from sources (such as pp and 8B) are given in the units of per cm2 per second. The pp chain is responsible for more than 98% of the energy generation in the standard solar model. Neutrinos produced in the carbon-nitrogen-oxygen CNO chain are not important energetically and are difficult to detect experimentally. The arrows at the top of the figure indicate the energy thresholds for the ongoing neutrino experiments. [From the paper “Solar Neutrinos: Where We Are, Where We Are Going,” ApJ 467, 475 (1996).] Helioseismology Confirms the Standard Solar Model:  Helioseismology Confirms the Standard Solar Model This figure shows the excellent agreement between the calculated solar model and the measured (Sun) sound speeds, a fractional difference of 0.001 rms for all speeds measured between 0.05 R and 0.95 R. There are no free parameters in the solar models. The figure shows the fractional difference between the predicted model sound speed and the measured solar values as a function of radial position in the sun (R is the solar radius). The vertical scale is chosen so as to emphasize that the fractional error is much smaller than generic fractional changes in the model, 0.03 to 0.08, that might significantly affect the solar neutrino predictions. This excellent agreement gives astronomers confidence that they are not responsible for the solar neutrino problems. [Ref. hys. Lett. B, 433, 1 (1998), astro-ph/9805135.] Total Rates: Standard Model vs. Experiment:  Total Rates: Standard Model vs. Experiment Predicted versus observed rates: The total rates in all five solar neutrino experiments are less than the rates predicted by the standard solar model. http://www.sns.ias.edu/~jnb/SNviewgraphs/snviewgraphs.html

Add a comment

Related presentations

Related pages

Nuclear Fusion : WNA - World Nuclear Association

Nuclear Fusion Power (Updated October 2016) Fusion power offers the prospect of an almost inexhaustible source of energy for future generations, but it ...
Read more

Nuclear Fusion - Georgia State University

Nuclear Fusion. If light nuclei are forced together, they will fuse with a yield of energy because the mass of the combination will be less than the sum of ...
Read more

Nuclear fusion - ScienceDaily

In physics, nuclear fusion is the process by which multiple nuclei join together to form a heavier nucleus. It is accompanied by the release or absorption ...
Read more

nuclear fusion | physics | Britannica.com

Nuclear fusion, process by which nuclear reactions between light elements form heavier elements (up to iron). In cases where the interacting nuclei belong ...
Read more

What is Fusion ? Definition & Facts about Nuclear Energy

Nuclear Fusion is a Real Possibility, New Models Suggest; Power the Future: 10 Ways to Run the 21st Century; Top Ten Disruptive Technologies;
Read more

Nuclear fusion - Wikipedia, the free encyclopedia

In nuclear physics, nuclear fusion is a nuclear reaction in which two or more atomic nuclei come close enough to form one or more different atomic nuclei ...
Read more

Nuclear fusion - Simple English Wikipedia, the free ...

Nuclear fusion is the process of making a single heavy nucleus (part of an atom) from two lighter nuclei. This process is called a nuclear reaction.
Read more

Fusión nuclear - Wikipedia, la enciclopedia libre

La fusión nuclear se logra por medio de compresión-descompresión, aumentando o disminuyendo la intensidad del campo eléctrico.
Read more

Nuclear Fusion | Nuclear Fusion | Science | atomicarchive.com

Nuclear Fusion. Nuclear energy can also be released by fusion of two light elements (elements with low atomic numbers). The power that fuels the sun and ...
Read more

What is nuclear fusion? - Definition from WhatIs.com

Nuclear fusion is an atomic reaction in which multiple atoms combine to create a single, more massive atom. The resulting atom has slightly smaller mass ...
Read more