Bubble Chamber Event. Resonances last typically for a mere 10(-23 power) seconds and therefore leave no discernible track in a bubble chamber. But by calculating back from the energies and angles of the particles that are detected, physicists can infer that a resonance has existed. In this picture from a bubble chamber at Berkley, an antiproton, coming from below, annihilates with a proton to produces two negative pions, a neutral pion and two positive pions. The negative pions move off to the left, the positive pions to the right, while the pi-zero is undetected. The lower pi-plus decays to a muon, the short piece of track, and then to a positron, which curls out of the picture. The information in the picture is consistent with the lower-energy pions, the lower tracks on left and right-being the decay products of a resonance state known as the omega. Image not dated. Bubble Chamber-1041
Summary
Digital Preservation File Name and Format: 434-LB-6-XBD9708-03162.TIF
Photographs Documenting Scientists, Special Events, and Nuclear Research Facilities, Instruments, and Projects at the Berkeley Lab
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Date
1996 - 2014
Source
The U.S. National Archives
Copyright info
Restricted - Possibly Specific Use Restriction: Copyright Note: The University of California, as the Department of Energy contractor managing the historical image scanning project, has asserted a continuing legal interest in the digital versions of the images included in the NARA accession, and, accordingly, has stipulated that anyone intending to use any of these digital images for commercial purposes, including textbooks, commercial materials, and periodicals, must obtain prior permission from the University of California-Lawrence Berkeley National Lab, through [email protected].