[Recorded on 05.30.2019] Continuing the investigation from

https://drupal.star.bnl.gov/STAR/blog/dmawxc/update-05212019-run-9-embedding-track-qa-cuts-different-ranges-ptmc
https://drupal.star.bnl.gov/STAR/blog/dmawxc/update-05232019-run-9-embedding-track-matching-quantities-different-ranges-ptmc
https://drupal.star.bnl.gov/STAR/blog/dmawxc/update-05242019-run-9-embedding-more-tracking-matching-quantities-different-ranges-ptmc

We still haven't figured out what exactly causes this mysterious dip in the reconstructed track pT spectrum. We suspect it may have to do with our detector-to-particle track matching process. So below shows the detector-to-particle ratio for matched reconstructed tracks and all reconstructed tracks. In other words, here is the ratio of the pT spectrum of matched reconstructed tracks to the particle-level pT spectrum:

And here is the ratio of the pT spectrum of all reconstructed tracks (before and after QA cuts) to the particle-level pT spectrum:

And here is the ratio using all reconstructed tracks (after QA cuts) compared to the ratio using the matched reconstructed tracks:

Alarming! There *should* be more tracks when we use all reconstructed tracks (the matched tracks are a subset of all reconstructed tracks), so the detector-to-particle ratio should be higher! So there's some sort of bug here...