Home > Publications database > Suppression of Light $q\bar{q}$ Backgrounds with Multivariate Techniques in the Measurement of Radiative B-Meson Decays > print

001     615859
005     20241015213442.0
037 _ _ |a PUBDB-2024-06300
041 _ _ |a English
100 1 _ |a Sulimann, Sen
|0 P:(DE-H253)PIP1110338
|b 0
|e Corresponding author
|g male
245 _ _ |a Suppression of Light $q\bar{q}$ Backgrounds with Multivariate Techniques in the Measurement of Radiative B-Meson Decays
|f 2024-04-22 - 2024-09-30
260 _ _ |a Hamburg
|c 2024
300 _ _ |a 66
336 7 _ |a bachelorThesis
|2 DRIVER
336 7 _ |a Thesis
|0 2
|2 EndNote
336 7 _ |a Output Types/Supervised Student Publication
|2 DataCite
336 7 _ |a Bachelor Thesis
|b bachelor
|m bachelor
|0 PUB:(DE-HGF)2
|s 1728992728_1708574
|2 PUB:(DE-HGF)
336 7 _ |a MASTERSTHESIS
|2 BibTeX
336 7 _ |a SUPERVISED_STUDENT_PUBLICATION
|2 ORCID
502 _ _ |a Bachelorarbeit, University of Hamburg, 2024
|c University of Hamburg
|b Bachelorarbeit
|d 2024
|o 2024-09-30
520 _ _ |a The Standard Model of particle physics has been highly successful in describing fundamental particles and their interactions, but potential extensions are needed to address itslimitations. Precise measurements of rare decays, such as the radiative B → Xsγ decay, provide an opportunity to test Beyond Standard Model (BSM) theories, due to them being suppressed by the Standard Model. This thesis focuses on the suppression of lightquark-antiquark ($q\bar{q}$) continuum backgrounds, a dominant source of noise in the analysis of the B → $X_sγ$ decay, using multivariate classification techniques to improve the signal to -background ratio. Furthermore, an attempt is made to suppress $B\bar{B}$-backgrounds. In particular, Boosted Decision Trees (BDTs) are trained to differentiate the rare B → $X_sγ$ signal from continuum and $B\bar{B}$-backgrounds. Specifically, two approaches are employed: multi-class classifiers and the consecutive application of binary classifiers. The data analyzed were collected by the Belle II detector from $e^+e^−$ -collisions at the SuperKEKB collider in Japan. The work presented in this thesis includes the selection and analysis of discriminating variables, the development and training of BDTs, and the evaluation of their performance. The trained models demonstrate promising results in suppressing background noise, especially continuum events. The analysis provides valuable insights into the variable importance and limitations of the single approaches, as well as the potential for future refinement.
536 _ _ |a 611 - Fundamental Particles and Forces (POF4-611)
|0 G:(DE-HGF)POF4-611
|c POF4-611
|f POF IV
|x 0
693 _ _ |a KEK
|e KEK: BELLE I/II
|1 EXP:(DE-H253)KEK-20150101
|0 EXP:(DE-H253)BELLE-20150101
|5 EXP:(DE-H253)BELLE-20150101
|x 0
700 1 _ |a Tackmann, Kerstin
|0 P:(DE-H253)PIP1013754
|b 1
|e Thesis advisor
700 1 _ |a Moreira de Carvalho, Ana Luisa
|0 P:(DE-H253)PIP1099444
|b 2
|e Thesis advisor
856 4 _ |u https://bib-pubdb1.desy.de/record/615859/files/Bachelor_Thesis_Sen_Sulimann.pdf
|y Restricted
856 4 _ |u https://bib-pubdb1.desy.de/record/615859/files/Bachelor_Thesis_Sen_Sulimann.pdf?subformat=pdfa
|x pdfa
|y Restricted
909 C O |o oai:bib-pubdb1.desy.de:615859
|p VDB
910 1 _ |a External Institute
|0 I:(DE-HGF)0
|k Extern
|b 0
|6 P:(DE-H253)PIP1110338
910 1 _ |a Deutsches Elektronen-Synchrotron
|0 I:(DE-588b)2008985-5
|k DESY
|b 1
|6 P:(DE-H253)PIP1013754
910 1 _ |a Deutsches Elektronen-Synchrotron
|0 I:(DE-588b)2008985-5
|k DESY
|b 2
|6 P:(DE-H253)PIP1099444
913 1 _ |a DE-HGF
|b Forschungsbereich Materie
|l Matter and the Universe
|1 G:(DE-HGF)POF4-610
|0 G:(DE-HGF)POF4-611
|3 G:(DE-HGF)POF4
|2 G:(DE-HGF)POF4-600
|4 G:(DE-HGF)POF
|v Fundamental Particles and Forces
|x 0
914 1 _ |y 2024
920 _ _ |l yes
920 1 _ |0 I:(DE-H253)BELLE-20210408
|k BELLE
|l BELLE II Experiment
|x 0
980 _ _ |a bachelor
980 _ _ |a VDB
980 _ _ |a I:(DE-H253)BELLE-20210408
980 _ _ |a UNRESTRICTED

LibraryCollectionCLSMajorCLSMinorLanguageAuthor
Marc 21