@article{1468277,
      recid = {1468277},
      author = {Burzynski, Jackson.},
      title = {A search for exotic Higgs decays : Or: How I learned to  stop worrying and love long-lived particles /},
      publisher = {Springer,},
      address = {Cham :},
      pages = {1 online resource (201 p.).},
      year = {2023},
      note = {"Doctoral thesis accepted by University of Massachusetts  Amherst, Amherst, USA."},
      abstract = {This work describes a search for exotic decays of the  Higgs boson to two long-lived, neutral, spin-0 particles  which subsequently decay to pairs of b quarks, giving the  striking signature of displaced hadronic jets in the ATLAS  inner detector. Several other ATLAS searches have probed  this decay topology previously, excluding branching ratios  of the Higgs boson to long-lived particles (LLPs) of more  than 10% for proper lifetimes greater than 100mm. These  searches relied on dedicated triggers designed to select  events with LLPs decaying in the ATLAS calorimeter or muon  spectrometer. The lack of an equivalent trigger for LLP  decays in the ATLAS inner detector has been a limiting  factor in probing LLP lifetimes less than 100mm. To  circumvent the difficulty of triggering on LLP decays, the  search presented in this thesis exploits the ZH associated  production mode, relying on leptonic trigger signatures to  select interesting events. This is the first search for  Higgs boson decays into LLPs to exploit this analysis  methodology and additionally makes use of several novel  methods for both background rejection and background  estimation. No excess over Standard Model predictions is  observed, and upper limits are set on the branching ratio  of the Higgs boson to LLPs . Depending on the mass of the  LLP, branching ratios greater than 10% are excluded for  lifetimes as small as 4mm and as large as 100mm, probing an  important gap in the ATLAS exotic Higgs decay programme. In  comparison to the previous searches for Higgs decays to  LLPs, these are among the most stringent limits placed on  this scenario, and for LLPs with masses below 40 GeV these  results represent the strongest existing constraints on the  branching ratio of the Higgs boson to LLPs in this lifetime  regime.},
      url = {http://library.usi.edu/record/1468277},
      doi = {https://doi.org/10.1007/978-3-031-30466-8},
}