- HERMES experiment
HERMES is an experiment being conducted using the HERA particle accelerator located at
DESY inHamburg . The experiment's goal is to investigate thequark -gluon structure ofmatter by examining how a nucleon's constituents affect its spin. HERMES completed its first run between1995 and2000 , and a second run began in2001 and is scheduled to end during the summer of2007 .HERMES is being conducted by
scientist s from more than 13 countries.Method
Polarized electrons are fired at polarized gas targets. The virtual photon emitted by the electron is also polarized and so seeks out quarks of spin in the same direction as the photon. The asymmertry of ejected quarks is found to deduce the net polarisation of the quarks.
UGFS
The unpolarized gas feed system was used for non polarized "end of fill" or heavy target running before the polarized target was removed in 2003. Currently the UGFS supplies the target gasses in the new detector configuration.
ources
* [http://www-hermes.desy.de HERMES]
* [http://www.markusehrenfried.de/science/physics/hermes/theheraaccelerat.html http://www.markusehrenfried.de/science/physics/hermes/theheraaccelerat.html]
* [http://nuclear.gla.ac.uk/~protopop/teaching/gui/ http://nuclear.gla.ac.uk/~protopop/teaching/gui/]
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