In the Large Hadron Collider, the way particles are detected (specifically in ATLAS) is analogous to detecting photons using a photodiode(analogous is an exaggeration, but will suffice for the question ). But a single particle passing through the silicon pixel detector can also hit its adjacent pixels. In fact, it almost always does that. Now why this happens is closely related to the fact that these particles are highly energetic. There may be the uncertainty principle into play because more pixels means less resolution in position. But I want to know if there is another physical view of this as well, like energy leakage to adjacent pixels? And how do the MC simulations model this?

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    $\begingroup$ One can see muon streaks in ordinary digital cameras. Here is a track that I acquired with a simple setup: gammaspectacular.com/phpBB3/viewtopic.php?t=139 $\endgroup$ – Pieter Dec 3 '18 at 22:35
  • $\begingroup$ Thanks. I understand from your example that if the trajectory is at a small enough angle to the detectors plane, then the same particle will go through multiple detector pixels. But do you think a particle perpendicular to the detector plane can affect the nearby pixels? $\endgroup$ – SagarM Dec 3 '18 at 22:53
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    $\begingroup$ I do not know anything about the ATLAS detectors. And in the measurement with my camera chip I do not have much control of the angle incidence (they are very roughly vertical, give "spots" in the camera chip). There is a nice write-up here: arxiv.org/abs/1511.00660 $\endgroup$ – Pieter Dec 3 '18 at 23:13
  • $\begingroup$ The tracker of atlas is described here atlas.cern/discover/detector/inner-detector. It picks up with the pixels "points" on the charged tracks which are then fitted to a single track with programs. It needs recordings of hits, but it is not a solid detector, it samples the tracks and this leaves room for corrections by knowing the response of the pixels to charged tracks. Similar to measuring tracks in a bubble chamber, cds.cern.ch/record/39469 a few clear points on the track were picked to get the event on the right. This is done with programs at LHC $\endgroup$ – anna v Dec 4 '18 at 5:51

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