{{short description|Particle physics experiment at CERN}} {{Use dmy dates|date=January 2018}} thumb|The streamer chamber of UA5, which had been operating at the Intersecting Storage Rings until Easter, was installed in its platform, alongside the UA2 detector and in September 1981 was moved into the beam|left thumb|First proton-antiproton collider interactions as seen by the streamer chamber of UA5 in April 1981, CERN thumb|Closeup of typical proton-antiproton interaction, as recorded in 1982
The '''UA5 experiment''' was the first experiment conducted at the Proton-Antiproton Collider ('''Sp{{overline|p}}S'''), a collider using the infrastructure of the Super Proton Synchrotron (SPS). The experiment was approved in February 1979, as a collaboration between CERN and the universities of Bonn, Brussels, Cambridge and Stockholm.<ref name=proposal>{{Cite web|url=https://cds.cern.ch/record/1009444/files/CM-P00063814.pdf|title=Decisions of the 32nd Meeting of the Research Board|last=Goldchmidt-Clermont|first=Y.|date=15 February 1979|website=CERN Document Server|access-date=18 July 2017}}</ref> The spokesperson of the UA5 collaboration was John Rushbrooke.<ref>{{cite web |url=https://greybook.cern.ch/greybook/experiment/detail?id=UA5 |title=UA5 |author=<!--Not stated--> |website=CERN Greybook |publisher=CERN |access-date=18 July 2017}}</ref>
The object of the experiment was to investigate Centauro events<ref name=proposal/> and more generally to perform a first rapid visual survey of the energy region afforded by the then new SPS collider.<ref name="Rushbrooke">{{Cite journal |last=Rushbrooke |first=John |title=The UA5 Streamer Chamber Experiment at the SPS p-pbar Collider |journal=Physica Scripta |volume=23 |issue=4B |pages=642–648 |doi=10.1088/0031-8949/23/4B/006 |year=1981 |bibcode=1981PhyS...23..642B }}</ref> Measurements were done on proton-antiproton collisions of 540 GeV center-of-mass energy, with the results being published in November 1983.<ref name=540GeV>{{cite journal|last1=Alpgård|first1=K.|display-authors=etal|title=Particle multiplicities in interactions at √s=540 GeV|journal=Physics Letters B|date=January 1983|volume=121|issue=2–3|pages=209–215|doi=10.1016/0370-2693(83)90916-4|bibcode=1983PhLB..121..209A|url=https://cds.cern.ch/record/141201/files/198212126.pdf}}</ref> Later, under the name of UA5/2, data was recorded from 900 GeV collisions.<ref name=900GeV>{{cite conference |url=https://cds.cern.ch/record/154847/files/cer-000066115.pdf |title=Results from the UA5 Experiment at the CERN pp-collider |last1=Geich-Gimbel |first1=Ch.|date=9 July 1984 |publisher=Bonn University |location=Durham, UK |conference=VIIth European Symposium on Antiproton Interaction}}</ref> No indication of Centauro production was observed, but an upper limit on the production was obtained.<ref name=900GeV/>
The experimental setup consisted of two large streamer chambers which were placed above and below the Sp{{overline|p}}S beam pipe. The chambers were triggered by requiring hits in scintillation counters at each end. This trigger rejected essentially all elastic and diffractive elements.<ref name=540GeV/> The streamer chamber tracks were photographed by six cameras, and the tracks were measured, reconstructed and analyzed.
==See also== *List of Super Proton Synchrotron experiments *UA1 experiment *UA2 experiment
==References== {{Reflist|30em}}
==External links== *[https://cds.cern.ch/search?c=CERN+Committee+Documents&c=Published+Articles&p=UA5&f=experiment List of publications from the UA5 Collaboration] *[https://inspirehep.net/experiments/1109610 CERN-UA-05 experiment record] on INSPIRE-HEP
{{SPS experiments}} {{CERN}}
Category:Particle experiments Category:CERN experiments