TY  - JOUR
AU  - Blekman, Freya
AU  - Moor, De
AU  - Gautam, Kunal
AU  - Ploerer, Eduardo
AU  - Ilg, Armin
AU  - Macchiolo, Anna
AU  - Canellli, Florencia
TI  - Tagging more quark jet flavours at FCC-ee at 91 GeV with a transformer-based neural network
JO  - The European physical journal / C
VL  - 85
IS  - 2
SN  - 1434-6044
CY  - Heidelberg
PB  - Springer
M1  - PUBDB-2024-01826
M1  - DESY-24-086
M1  - arXiv:2406.08590
SP  - 165
PY  - 2024
AB  - Jet flavour tagging is crucial in experimental high-energy physics. A tagging algorithm, <tt>DeepJetTransformer</tt>, is presented, which exploits a transformer-based neural network that is substantially faster to train. The <tt>DeepJetTransformer</tt> network uses information from particle flow-style objects and secondary vertex reconstruction as is standard for b- and c-jet identification supplemented by additional information, such as reconstructed V<sup>0</sup>s and K<sup>±</sup>/π<sup>±</sup> discrimination, typically not included in tagging algorithms at the LHC. The model is trained as a multiclassifier to identify all quark flavours separately and performs excellently in identifying b- and c-jets. An s-tagging efficiency of 40% can be achieved with a 10%ud-jet background efficiency. The impact of including V<sup>0</sup>s and K<sup>±</sup>/π<sup>±</sup> discrimination is presented. The network is applied on exclusive Z → q―q samples to examine the physics potential and is shown to isolate Z → s―s events. Assuming all other backgrounds can be efficiently rejected, a 5σ discovery significance for Z → s―s can be achieved with an integrated luminosity of 60 \textnb<sup>−1</sup>, corresponding to less than a second of the FCC-ee run plan at the Z resonance.
KW  - jet, flavor (INSPIRE)
KW  - track data analysis, vertex (INSPIRE)
KW  - vertex, secondary (INSPIRE)
KW  - quark, flavor (INSPIRE)
KW  - network (INSPIRE)
KW  - efficiency (INSPIRE)
KW  - FCC-ee (INSPIRE)
KW  - background (INSPIRE)
KW  - neural network (INSPIRE)
KW  - CERN LHC Coll (INSPIRE)
LB  - PUB:(DE-HGF)16
C6  - pmid:39935486
UR  - <Go to ISI:>//WOS:001416920500001
DO  - DOI:10.1140/epjc/s10052-025-13785-y
UR  - https://bib-pubdb1.desy.de/record/607315
ER  -