Search for top quark decays $t \to qH$ with $H \to \gamma\gamma$ using the ATLAS detector

Aad, Georges; Abbott, Brad; Abdallah, Jalal; Abdel Khalek, Samah; Abdinov, Ovsat; Aben, Rosemarie; Abi, Babak; Abolins, Maris; AbouZeid, Ossama; Abramowicz, Halina

doi:10.1007/JHEP06(2014)008

Search for top quark decays $t \to qH$ with $H \to \gamma\gamma$ using the ATLAS detector

ATLAS

Collaboration

Mar 25, 2014

40 pages

Published in:

JHEP 06 (2014) 008

Published: 2014

e-Print:

1403.6293 [hep-ex]

DOI:

10.1007/JHEP06(2014)008

PDG:

{{\mathit t}}

\rightarrow

{{\mathit H}}{{\mathit u}}

Report number:

CERN-PH-EP-2014-036

Experiments:

CERN-LHC-ATLAS

View in:

reference search124 citations

Citations per year

Abstract: (arXiv)

A search is performed for flavour-changing neutral currents in the decay of a top quark to an up-type (

c, u

) quark and a Higgs boson, where the Higgs boson decays to two photons. The proton-proton collision data set used corresponds to 4.7 fb

^{-1}

at

\sqrt{s}

= 7 \tev\ and 20.3 fb

^{-1}

at

\sqrt{s}

= 8 \tev\ collected by the ATLAS experiment at the LHC. Top quark pair events are searched for in which one top quark decays to

qH

and the other decays to

bW

. Both the hadronic and the leptonic decay modes of the

W

boson are used. No significant signal is observed and an upper limit is set on the

t\rightarrow qH

branching ratio of 0.79% at the 95% confidence level. The corresponding limit on the

tqH

coupling combination

\sqrt{\lambda_{tcH}^{2} + \lambda_{tuH}^{2}}

is 0.17.

Note:

22 pages plus author list (45 pages total), 6 figures, 4 tables, submitted to JHEP. All figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HIGG-2013-09

Hadron-Hadron Scattering
top: rare decay
Higgs particle: radiative decay
p p: scattering
ATLAS
neutral current: flavor changing
top: branching ratio: upper limit
CERN LHC Coll
W: decay modes
final state: two-photon

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