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Title: Top-philic Z' forces at the LHC

Despite extensive searches for an additional neutral massive gauge boson at the LHC, a $$Z^\prime$$ at the weak scale could still be present if its couplings to the first two generations of quarks are suppressed, in which case the production in hadron colliders relies on tree-level processes in association with heavy flavors or one-loop processes in association with a jet. Here, we consider the low-energy effective theory of a top-philic $Z'$ and present possible UV completions. We clarify theoretical subtleties in evaluating the production of a top-philic $Z'$ at the LHC and examine carefully the treatment of an anomalous $Z'$ current in the low-energy effective theory. Recipes for properly computing the production rate in the $Z'+j$ channel are given. We discuss constraints from colliders and low-energy probes of new physics. As an application, we apply these considerations to models that use a weak-scale $Z'$ to explain possible violations of lepton universality in $B$ meson decays, and show that the future running of a high luminosity LHC can potentially cover much of the remaining parameter space favored by this particular interpretation of the $B$ physics anomaly.
 [1] ;  [2] ;  [3] ;  [4] ;  [1] ;  [3]
  1. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States). Theoretical Physics Dept.
  2. Argonne National Lab. (ANL), Argonne, IL (United States). Dept. of High Energy Physics
  3. (United States). Dept. of Physics and Astronomy
  4. (CERN), Geneva (Switzerland). Theoretical Physics Dept.
Publication Date:
Report Number(s):
FERMILAB-PUB-18-005-T; NUHEP-TH-18-01; arXiv:1801.03505
Journal ID: ISSN 1029-8479; 1647561
Grant/Contract Number:
AC02-07CH11359; SC0010143; AC02-06CH11357; SC0007859
Accepted Manuscript
Journal Name:
Journal of High Energy Physics (Online)
Additional Journal Information:
Journal Name: Journal of High Energy Physics (Online); Journal Volume: 2018; Journal Issue: 3; Journal ID: ISSN 1029-8479
Springer Berlin
Research Org:
Argonne National Lab. (ANL), Argonne, IL (United States); Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25); Northwestern Univ., Evanston, IL (United States)
Country of Publication:
United States
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 79 ASTRONOMY AND ASTROPHYSICS; Anomalies in Field and String Theories; Beyond Standard Model
OSTI Identifier: