This is the 3rd of 4 short online videos. It explains what is: strangeness enhancement; centrality of lead-lead collisions; efficiency, yield, background etc. More details and related links on this indico event page.
In more detail: What is Physics Master Classes
Students after morning lectures, run programmes in the afternoon to do measurements. These tutorials are about how to use the software required to do these measurements.
Background info and examples Looking for strange particles with ALICE http://aliceinfo.cern.ch/Public/MasterCL/MasterClassWebpage.html
This use case was present in the original e-learning project description http://it-student-projects.web.cern.ch/projects/e-learning-modules
This recording was done with quicktime on Despina's Mac.
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