PT Journal
AU ATLAS Collaboration (Aaboud, Mea
   Alvarez Piqueras, D
   Aparisi Pozo, JA
   Bailey, AJ
   Cabrera Urban, S
   Castillo, FL
   Castillo Gimenez, V
   Cerda Alberich, L
   Costa, MJ
   Escobar, C
   Estrada Pastor, O
   Ferrer, A
   Fiorini, L
   Fullana Torregrosa, E
   Fuster, J
   Garcia, C
   Garcia Navarro, JE
   Gonzalez de la Hoz, S
   Gonzalvo Rodriguez, GR
   Guerrero Rojas, JGR
   Higon-Rodriguez, E
   Jimenez Pena, J
   Lacasta, C
   Lozano Bahilo, JJ
   Madaffari, D
   Mamuzic, J
   Marti-Garcia, S
   Melini, D
   Miñano, M
   Mitsou, VA
   Rodriguez Bosca, S
   Rodriguez Rodriguez, D
   Ruiz-Martinez, A
   Salt, J
   Santra, A
   Soldevila, U
   Sanchez, J
   Valero, A
   Valls Ferrer, JA
   Vos, M
TI Measurement of the jet mass in high transverse momentum Z(-> b(b)over-bar)gamma production at root s=13 TeV using the ATLAS detector
SO Physics Letters B
JI Phys. Lett. B
PY 2021
BP 135991
EP 23pp
VL 812
DI 10.1016/j.physletb.2020.135991
LA English
AB The integrated fiducial cross-section and unfolded differential jet mass spectrum of high transverse momentum Z -> b (b) over bar decays are measured in Z gamma events in proton-proton collisions at root s = 13 TeV. The data analysed were collected between 2015 and 2016 with the ATLAS detector at the Large Hadron Collider and correspond to an integrated luminosity of 36.1 fb(-1). Photons are required to have a transverse momentum p(T) > 175 GeV. The Z -> b (b) over bar decay is reconstructed using a jet with p(T) > 200 GeV, found with the anti-k(t) R = 1.0 jet algorithm, and groomed to remove soft and wide-angle radiation and to mitigate contributions from the underlying event and additional proton-proton collisions. Two different but related measurements are performed using two jet grooming definitions for reconstructing the Z -> b (b) over bar decay: trimming and soft drop. These algorithms differ in their experimental and phenomenological implications regarding jet mass reconstruction and theoretical precision. To identify Zbosons, b-tagged R = 0.2 track-jets matched to the groomed large-R calorimeter jet are used as a proxy for the b-quarks. The signal yield is determined from fits of the data-driven background templates to the different jet mass distributions for the two grooming methods. Integrated fiducial cross-sections and unfolded jet mass spectra for each grooming method are compared with leading-order theoretical predictions. The results are found to be in good agreement with Standard Model expectations within the current statistical and systematic uncertainties.
ER