Opened 4 years ago
#1485 new Bug
Unphysical HCAL resolution
| Reported by: | Taewook Youn | Owned by: | |
|---|---|---|---|
| Priority: | critical | Milestone: | |
| Component: | Delphes code | Version: | Delphes 3 |
| Keywords: | Cc: |
Description
Hello Delphes team,
I am studying the MET distribution from dijet misalignment with default delphes_card_ATLAS card.
However, I see that as the minimum invariant pT decreases (http://home.thep.lu.se/~torbjorn/pythia82html/PhaseSpaceCuts.html), say 100 to 80 GeV, the total number of events passing pT cut (e.g. > 140 GeV) increases significantly, resulting in large MET (e.g. > 140 GeV) due to the dijet misalignment.
This effect goes away when I manually turn off (set to 0) the Delphes HCAL smearing.
If you take a look at gen-level jets and Delphes jets, the large MET seems to be driven by the emergence of extremely energetic jet arising from a massive migration from relatively low jet pT at the generator level. I also attach a few examples of the events.
At this point, we are inclined to consider this unphysical phenomenon as a bug, so submitting a bug report.
Hope I can hear from you soon.
Best,
Ty
Examples of events which have large jet arising from unphysical energetic jets