# ${\boldsymbol {\boldsymbol t}}$-quark DECAY WIDTH INSPIRE search

VALUE (GeV) CL% DOCUMENT ID TECN  COMMENT
$\bf{ 1.41 {}^{+0.19}_{-0.15}}$ OUR AVERAGE  Error includes scale factor of 1.4.
$1.36$ $\pm0.02$ ${}^{+0.14}_{-0.11}$ 1
 2014 E
CMS ${{\mathit \ell}}{{\mathit \ell}}$ +$\not E_T$+2-4jets (0-2${{\mathit b}}$-tag)
$2.00$ ${}^{+0.47}_{-0.43}$ 2
 2012 T
D0 $\Gamma$( ${{\mathit t}}$ $\rightarrow$ ${{\mathit b}}{{\mathit W}}$ )/B( ${{\mathit t}}$ $\rightarrow$ ${{\mathit b}}{{\mathit W}}$ )
• • • We do not use the following data for averages, fits, limits, etc. • • •
$<6.38$ 95 3
 2013 Z
CDF ${{\mathit \ell}}+\not E_T+{}\geq{}$4j (${}\geq{}$0 ${{\mathit b}}$), direct
$1.99$ ${}^{+0.69}_{-0.55}$ 4
 2011 B
D0 Repl. by ABAZOV 2012T
$> 1.21$ 95 4
 2011 B
D0 ${{\mathit \Gamma}}$( ${{\mathit t}}$ $\rightarrow$ ${{\mathit W}}{{\mathit b}}$ )
$<7.6$ 95 5
 2010 AC
CDF ${{\mathit \ell}}$ + jets, direct
$<13.1$ 95 6
 2009 M
CDF ${\mathit m}_{{{\mathit t}}}$(rec) distribution
1  Based on 19.7 fb${}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ data at $\sqrt {s }$ = 8 TeV. The result is obtained by combining the measurement of ${{\mathit R}}$ = ${{\mathit \Gamma}}$( ${{\mathit t}}$ $\rightarrow$ ${{\mathit W}}{{\mathit b}}$ )/${{\mathit \Gamma}}$( ${{\mathit t}}$ $\rightarrow$ ${{\mathit W}}{{\mathit q}}$ (${{\mathit q}}={{\mathit b}},{{\mathit s}},{{\mathit d}}$)) and a previous CMS measurement of the ${{\mathit t}}$-channel single top production cross section of CHATRCHYAN 2012BQ, by using the theoretical calculation of ${{\mathit \Gamma}}$( ${{\mathit t}}$ $\rightarrow$ ${{\mathit W}}{{\mathit b}}$ ) for ${\mathit m}_{{{\mathit t}}}$ = 172.5 GeV.
2  Based on 5.4 fb${}^{-1}$ of data in ${{\mathit p}}{{\overline{\mathit p}}}$ collisions at 1.96 TeV. $\Gamma$( ${{\mathit t}}$ $\rightarrow$ ${{\mathit b}}{{\mathit W}}$ ) = $1.87$ ${}^{+0.44}_{-0.40}$ GeV is obtained from the observed ${{\mathit t}}$-channel single top quark production cross section, whereas B( ${{\mathit t}}$ $\rightarrow$ ${{\mathit b}}{{\mathit W}}$ ) = $0.90$ $\pm0.04$ is used assuming $\sum_{q}$B( ${{\mathit t}}$ $\rightarrow$ ${{\mathit q}}{{\mathit W}}$ ) = 1. The result is valid for ${\mathit m}_{{{\mathit t}}}$ = 172.5 GeV. See the paper for the values for ${\mathit m}_{{{\mathit t}}}$ = 170 or 175 GeV.
3  Based on 8.7 fb${}^{-1}$ of data. The two sided 68$\%$ CL interval is 1.10 GeV $<$ ${{\mathit \Gamma}_{{t}}}$ $<$ 4.05 GeV for ${\mathit m}_{{{\mathit t}}}$ = 172.5 GeV.
4  Based on 2.3 fb${}^{-1}$ in ${{\mathit p}}{{\overline{\mathit p}}}$ collisions at $\sqrt {s }$ = 1.96 TeV. ABAZOV 2011B extracted ${{\mathit \Gamma}_{{t}}}$ from the partial width ${{\mathit \Gamma}}$( ${{\mathit t}}$ $\rightarrow$ ${{\mathit W}}{{\mathit b}}$ ) = $1.92$ ${}^{+0.58}_{-0.51}$ GeV measured using the ${{\mathit t}}$-channel single top production cross section, and the branching fraction br{ {{\mathit t}} \rightarrow {{\mathit W}} {{\mathit b}} } = $0.962$ ${}^{+0.068}_{-0.066}$(stat)${}^{+0.064}_{-0.052}$(syst). The ${{\mathit \Gamma}}$( ${{\mathit t}}$ $\rightarrow$ ${{\mathit W}}{{\mathit b}}$ ) measurement gives the 95$\%$ CL lowerbound of ${{\mathit \Gamma}}$( ${{\mathit t}}$ $\rightarrow$ ${{\mathit W}}{{\mathit b}}$ ) and hence that of ${{\mathit \Gamma}_{{t}}}$.
5  Results are based on 4.3 fb${}^{-1}$ of data in ${{\mathit p}}{{\overline{\mathit p}}}$ collisions at $\sqrt {s }$ = 1.96 TeV. The top quark mass and the hadronically decaying ${{\mathit W}}$ boson mass are reconstructed for each candidate events and compared with templates of different top quark width. The two sided 68$\%$ CL interval is 0.3 GeV$<$ ${{\mathit \Gamma}_{{t}}}<$ 4.4 GeV for ${\mathit m}_{{{\mathit t}}}$ = 172.5 GeV.
6  Based on 955 pb${}^{-1}$ of ${{\mathit p}}{{\overline{\mathit p}}}$ collision data at $\sqrt {s }$ = 1.96 TeV. AALTONEN 2009M selected ${{\mathit t}}{{\overline{\mathit t}}}$ candidate events for the ${{\mathit \ell}}$ + $\not E_T$ + jets channel with one or two ${{\mathit b}}$-tags, and examine the decay width dependence of the reconstructed ${\mathit m}_{{{\mathit t}}}$ distribution. The result is for ${\mathit m}_{{{\mathit t}}}$ =175 GeV, whereas the upper limit is lower for smaller ${\mathit m}_{{{\mathit t}}}$.
References:
 KHACHATRYAN 2014E
PL B736 33 Measurement of the Ratio B( ${{\mathit t}}$ $\rightarrow$ ${{\mathit W}}{{\mathit b}}$ )/B( ${{\mathit t}}$ $\rightarrow$ ${{\mathit W}}{{\mathit q}}$ ) in ${{\mathit p}}{{\mathit p}}$ Collisions at $\sqrt {s }$ = 8 TeV
 AALTONEN 2013Z
PRL 111 202001 Direct Measurement of the Total Decay Width of the Top Quark
 ABAZOV 2012T
PR D85 091104 Improved Determination of the Width of the Top Quark
 ABAZOV 2011B
PRL 106 022001 Determination of the Width of the Top Quark
 AALTONEN 2010AC
PRL 105 232003 Direct Top-Quark Width Measurement at CDF
 AALTONEN 2009M
PRL 102 042001 Direct Bound on the Total Decay Width of the Top Quark in ${{\mathit p}}{{\overline{\mathit p}}}$ Collisions at $\sqrt {s }$ = 1.96 TeV
 CHATRCHYAN 2012BQ
JHEP 1212 035 Measurement of the Single-Top-Quark $\mathit t$-Channel Cross Section in ${{\mathit p}}{{\mathit p}}$ Collisions at $\sqrt {s }$ = 7 TeV