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A time projection chamber (TPC) is a particle measurement device. One of the biggest TPCs has been mounted within the ALICE experiment at CERN, and was put into operation in November 2009 within the Large Hadron Collider Experiment.

We provide still simulated data of the measurement of proton-proton collisions. Other particles are produced in the collision, and leave tracks in the gaseous volume of the TPC.  Along the track, the gas is ionized and emits electrons. The electrons produced in the ionization process are accelerated in the external electric field and drift towards the read-out chambers where they are detected with the help of highly charged wires. The electron clusters are measured at a certain location of the read-out chamber (radial distance from beam axis and angle phi) with a certain charge (number of electrons) and at a certain time - electrons that are freed close to the read-out chambers reach them first, while electrons close to the center arrive at the latest. Their time of arrival and their position on the readout chamber provides the information to reconstruct the original particle track, therefore time projection.


We ask for an intuitive auditory display of these tracks, that complements the visual display (in disambiguating the spatial directions) or can be used independently (e.g., for blind users).




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