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Title: Single top quark production in flavor-changing Z{sup '} models

Abstract

In some models with an extra U(1) gauge boson Z{sup '}, the gauge couplings of the Z{sup '} to different generations of fermions may not be universal. Flavor mixing in general can be induced at the tree level in the up-type and/or down-type quark sector after diagonalizing their mass matrices. In this work, we concentrate on the flavor mixing in the up-type quark sector. We deduce a constraint from D{sup 0}-D{sup 0} mixing. We study in detail single top-quark production via flavor-changing Z{sup '} exchange at the Large Hadron Collider (LHC) and the International Linear Collider (ILC). We found that for a typical value of M{sub Z{sup '}}=1 TeV, the production cross section at the LHC can be of the order of 1 fb. However, the background from the standard model single top-quark production makes it difficult to detect the flavor-changing Z{sup '} signal unless a decent charm tagging method is implemented. On the other hand, at the ILC, the production cross section at the resonance energy of {radical}(s){approx_equal}M{sub Z{sup '}} can reach a size of more than 100 fb. Even away from the resonance, the cross section at ILC is shown to be larger than the threshold of observabilitymore » of 0.01 fb.« less

Authors:
 [1];  [2];  [1];  [3];  [4];  [3];  [5]
  1. National Center for Theoretical Sciences, National Tsing Hua University, Hsinchu (China)
  2. (Morocco)
  3. (China)
  4. Department of Physics, National Central University, Chungli, Taiwan 320 (China)
  5. Department of Physics, National Tsing Hua University, Hsinchu (China)
Publication Date:
OSTI Identifier:
20782846
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 7; Other Information: DOI: 10.1103/PhysRevD.73.075015; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CERN LHC; CROSS SECTIONS; D NEUTRAL MESONS; FLAVOR MODEL; LINEAR COLLIDERS; MATRICES; MIXING; NEUTRAL CURRENTS; PARTICLE PRODUCTION; RESONANCE PARTICLES; REST MASS; STANDARD MODEL; T QUARKS; TEV RANGE; U-1 GROUPS; Z NEUTRAL BOSONS

Citation Formats

Arhrib, Abdesslam, Faculte des Sciences et Techniques, B.P 416 Tangier, Cheung, K., Department of Physics, National Tsing Hua University, Hsinchu, Chiang, C.-W., Institute of Physics, Academia Sinica, Taipei, Taiwan 115, and Yuan, T.-C. Single top quark production in flavor-changing Z{sup '} models. United States: N. p., 2006. Web. doi:10.1103/PHYSREVD.73.075015.
Arhrib, Abdesslam, Faculte des Sciences et Techniques, B.P 416 Tangier, Cheung, K., Department of Physics, National Tsing Hua University, Hsinchu, Chiang, C.-W., Institute of Physics, Academia Sinica, Taipei, Taiwan 115, & Yuan, T.-C. Single top quark production in flavor-changing Z{sup '} models. United States. doi:10.1103/PHYSREVD.73.075015.
Arhrib, Abdesslam, Faculte des Sciences et Techniques, B.P 416 Tangier, Cheung, K., Department of Physics, National Tsing Hua University, Hsinchu, Chiang, C.-W., Institute of Physics, Academia Sinica, Taipei, Taiwan 115, and Yuan, T.-C. Sat . "Single top quark production in flavor-changing Z{sup '} models". United States. doi:10.1103/PHYSREVD.73.075015.
@article{osti_20782846,
title = {Single top quark production in flavor-changing Z{sup '} models},
author = {Arhrib, Abdesslam and Faculte des Sciences et Techniques, B.P 416 Tangier and Cheung, K. and Department of Physics, National Tsing Hua University, Hsinchu and Chiang, C.-W. and Institute of Physics, Academia Sinica, Taipei, Taiwan 115 and Yuan, T.-C.},
abstractNote = {In some models with an extra U(1) gauge boson Z{sup '}, the gauge couplings of the Z{sup '} to different generations of fermions may not be universal. Flavor mixing in general can be induced at the tree level in the up-type and/or down-type quark sector after diagonalizing their mass matrices. In this work, we concentrate on the flavor mixing in the up-type quark sector. We deduce a constraint from D{sup 0}-D{sup 0} mixing. We study in detail single top-quark production via flavor-changing Z{sup '} exchange at the Large Hadron Collider (LHC) and the International Linear Collider (ILC). We found that for a typical value of M{sub Z{sup '}}=1 TeV, the production cross section at the LHC can be of the order of 1 fb. However, the background from the standard model single top-quark production makes it difficult to detect the flavor-changing Z{sup '} signal unless a decent charm tagging method is implemented. On the other hand, at the ILC, the production cross section at the resonance energy of {radical}(s){approx_equal}M{sub Z{sup '}} can reach a size of more than 100 fb. Even away from the resonance, the cross section at ILC is shown to be larger than the threshold of observability of 0.01 fb.},
doi = {10.1103/PHYSREVD.73.075015},
journal = {Physical Review. D, Particles Fields},
number = 7,
volume = 73,
place = {United States},
year = {Sat Apr 01 00:00:00 EST 2006},
month = {Sat Apr 01 00:00:00 EST 2006}
}
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