Hadronic calorimeter shower size: Challenges and opportunities for jet substructure in the superboosted regime

Shikma Bressler, Thomas Flacke, Yevgeny Kats, Seung Joon Lee, Gilad Perez

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Hadrons have finite interaction size with dense material, a basic feature common to known forms of hadronic calorimeters (HCAL). We argue that substructure variables cannot use HCAL information to access the microscopic nature of jets much narrower than the hadronic shower size, which we call superboosted massive jets. It implies that roughly 15% of their transverse energy profile remains inaccessible due to the presence of long-lived neutral hadrons. This part of the jet substructure is also subject to order-one fluctuations. We demonstrate that the effects of the fluctuations are not reduced when a global correction to jet variables is applied. The above leads to fundamental limitations in the ability to extract intrinsic information from jets in the superboosted regime. The neutral fraction of a jet is correlated with its flavor. This leads to an interesting and possibly useful difference between superboosted W/. Z/. h/. t jets and their corresponding backgrounds. The QCD jets that form the background to the signal superboosted jets might also be qualitatively different in their substructure as their mass might lie at or below the Sudakov mass peak. Finally, we introduce a set of zero-cone longitudinal jet substructure variables and show that while they carry information that might be useful in certain situations, they are not in general sensitive to the jet substructure.

Original languageEnglish
Pages (from-to)137-141
Number of pages5
JournalPhysics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
Volume756
DOIs
Publication statusPublished - 2016 May 10

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showers
substructures
calorimeters
hadrons
cones
quantum chromodynamics

ASJC Scopus subject areas

  • Nuclear and High Energy Physics

Cite this

Hadronic calorimeter shower size : Challenges and opportunities for jet substructure in the superboosted regime. / Bressler, Shikma; Flacke, Thomas; Kats, Yevgeny; Lee, Seung Joon; Perez, Gilad.

In: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, Vol. 756, 10.05.2016, p. 137-141.

Research output: Contribution to journalArticle

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