Free HEP dataset for teaching and demo purposes? I'm wondering if there are any free particle physics datasets out there, for use in teaching, demonstrations, developing analysis techniques etc.. I'm looking for data events e.g. as ROOT trees or in a similar format, together with a standard set of background events and postprocessing, or maybe even a simple framework with detector simulation to create my own events. I'm not looking for the very "raw" data, but something you could do a simple analysis on, like plot the dilepton mass and see resonances. The kind of experiment doesn't matter that much, as its for illustration purposes (can be e+e-, pp, medium or high energy).
Publishing raw data is common in other areas or fundamental (non-applied) research, especially in government-funded astronomy experiments. Imaging my astonishment when I started in this field that you couldn't just download "the data" from www.cern.ch as a torrent :-). For collaboration-political reasons, and because the data is considered too ununderstandable for laypersons, it is tightly controlled by the experiments. Yet, internally, especially on mature collaborations, you often have "the (processed) dataset", "the standard MC", "the standard corrections and uncertainties", and writing a simple analysis (for demonstration, not for publication) boils down to just writing custom code for event selection, so it should be entirely possible for a physics student or even an interested layperson to make a little sense of the data.
So, I believe that at least one of the now closed experiments (LEP, Tevatron, Hera, ...) might have published their framework and data, but I couldn't find anything on the net. Does anyone know of such a case?
 A: 
So, I believe that at least one of the now closed experiments (LEP, Tevatron, Hera, ...) might have published their framework and data, but I couldn't find anything on the net. Does anyone know of such a case?

I have found this misconception, that the framework and the data might be published or even should be published. It is like asking for a mission impossible. The experiments are so complicated that funny publications might come up from lack of expertise, nobody could guarantee that this would not happen. By funny I mean false resonance claims etc, which are instrumental effects that people who have no knowledge of the detectors could not correct for. 
People are thinking of data preservation of old experiments, but not at the level of graduate student classes, rather at the level of researchers spending the time necessary to be able to understand the data.
LEP experiments are still publishing, some of them with enormous author lists as they keep the original author list plus the new analysis people. Also I think I saw something new form a Tevatron experiment recently.
A: The LHC has published a significant amount of its data through the CERN Open Data program. In particular, enough data is included to, e.g. discover the Higgs boson for yourself. I believe they're close to the format you want, i.e. processed a bit for usability, but detailed enough to analyze independently.
