pdgLive

Single ${{\mathit t}}$-Quark Production Cross Section in ${{\mathit p}}{{\overline{\mathit p}}}$ Collisions at $\sqrt {s }$ = 1.96 TeV

Direct probes of the ${{\mathit t}}{{\mathit b}}{{\mathit W}}$ coupling and possible new physics at $\sqrt {s }$ = 1.96 TeV. OUR AVERAGE assumes that the systematic uncertainties are uncorrelated.

VALUE (pb)

CL%

DOCUMENT ID

TECN

COMMENT

• • We do not use the following data for averages, fits, limits, etc. • •

$3.53$ ${}^{+1.25}_{-1.16}$

CDF

${{\mathit s}}$- + ${{\mathit t}}$-channels (0${{\mathit \ell}}+\not E_T$ + 2,3j (${}\geq{}1{{\mathit b}}$-tag))

$2.25$ ${}^{+0.29}_{-0.31}$

TEVA

t-channel

$3.30$ ${}^{+0.52}_{-0.40}$

TEVA

s- + t-channels

$1.12$ ${}^{+0.61}_{-0.57}$

CDF

${{\mathit s}}$-channel (0${{\mathit \ell}}+\not E_T$+2,3j (${}\geq{}1{{\mathit b}}$-tag))

$1.41$ ${}^{+0.44}_{-0.42}$

CDF

${{\mathit s}}$-channel (${{\mathit \ell}}+\not E_T$+2j (${}\geq{}1{{\mathit b}}$-tag))

$1.29$ ${}^{+0.26}_{-0.24}$

TEVA

${{\mathit s}}$-channel (CDF + D0)

$3.04$ ${}^{+0.57}_{-0.53}$

CDF

${{\mathit s}}{+}$ ${{\mathit t}}{+}$ (${{\mathit \ell}}$ + $\not E_T$ + 2 or 3 jets (${}\geq{}1{{\mathit b}}$-tag))

$1.10$ ${}^{+0.33}_{-0.31}$

D0

s-channel

$3.07$ ${}^{+0.54}_{-0.49}$

D0

t-channel

$4.11$ ${}^{+0.60}_{-0.55}$

D0

s- + t-channels

$0.98$ $\pm0.63$

D0

${{\mathit s}}$-channel

$2.90$ $\pm0.59$

D0

${{\mathit t}}$-channel

$3.43$ ${}^{+0.73}_{-0.74}$

D0

${{\mathit s}}$- + ${{\mathit t}}$-channels

$1.8$ ${}^{+0.7}_{-0.5}$

CDF

${\mathit {\mathit s}}$-channel

$0.8$ $\pm0.4$

CDF

${\mathit {\mathit t}}$-channel

$4.9$ ${}^{+2.5}_{-2.2}$

CDF

$\not E_T$ + jets decay

$3.14$ ${}^{+0.94}_{-0.80}$

D0

${\mathit {\mathit t}}$-channel

$1.05$ $\pm0.81$

D0

${\mathit {\mathit s}}$-channel

$<7.3$

95

D0

${{\mathit \tau}}$ + jets decay

$2.3$ ${}^{+0.6}_{-0.5}$

CDF

${{\mathit s}}$- + ${{\mathit t}}$-channel

$3.94$ $\pm0.88$

D0

${{\mathit s}}$- + ${{\mathit t}}$-channel

$2.2$ ${}^{+0.7}_{-0.6}$

CDF

${{\mathit s}}$- + ${{\mathit t}}$-channel

$4.7$ $\pm1.3$

D0

${{\mathit s}}$- + ${{\mathit t}}$-channel

$4.9$ $\pm1.4$

D0

${{\mathit s}}$- + ${{\mathit t}}$-channel

$<6.4$

95

D0

${{\mathit p}}$ ${{\overline{\mathit p}}}$ $\rightarrow$ ${{\mathit t}}{{\mathit b}}{+}$ ${{\mathit X}}$

$<5.0$

95

D0

${{\mathit p}}$ ${{\overline{\mathit p}}}$ $\rightarrow$ ${{\mathit t}}{{\mathit q}}{{\mathit b}}{+}$ ${{\mathit X}}$

$<10.1$

95

CDF

${{\mathit p}}$ ${{\overline{\mathit p}}}$ $\rightarrow$ ${{\mathit t}}{{\mathit q}}{{\mathit b}}{+}$ ${{\mathit X}}$

$<13.6$

95

CDF

${{\mathit p}}$ ${{\overline{\mathit p}}}$ $\rightarrow$ ${{\mathit t}}{{\mathit b}}{+}$ ${{\mathit X}}$

$<17.8$

95

CDF

${{\mathit p}}$ ${{\overline{\mathit p}}}$ $\rightarrow$ ${{\mathit t}}{{\mathit b}}{+}$ ${{\mathit X}}$, ${{\mathit t}}{{\mathit q}}{{\mathit b}}{+}$ ${{\mathit X}}$

¹

AALTONEN 2016 based on 9.5 fb${}^{-1}$ of data. This includes, as a part, the result of AALTONEN 2014K. Combination of this result with that of AALTONEN 2014O gives a ${{\mathit s}}{+}$ ${{\mathit t}}$ cross section of $3.02$ ${}^{+0.49}_{-0.48}$ pb and $\vert \mathit V_{\mathit tb}\vert $ $>$ 0.84 (95$\%$ CL).

²

AALTONEN 2015H based on 9.7 fb${}^{-1}$ of data per experiment. The result is for ${\mathit m}_{{{\mathit t}}}$ = 172.5 GeV, and is a combination of the CDF measurements (AALTONEN 2016) and the D0 measurements (ABAZOV 2013O) on the ${{\mathit t}}$-channel single ${{\mathit t}}$-quark production cross section. The result is consistent with the NLO+NNLL SM prediction and gives $\vert \mathit V_{\mathit tb}\vert $ = $1.02$ ${}^{+0.06}_{-0.05}$ and $\vert \mathit V_{\mathit tb}\vert $ $>$ 0.92 (95$\%$ CL).

³	AALTONEN 2015H is a combined measurement of ${{\mathit s}}$-channel single top cross section by CDF + D0. AALTONEN 2014M is not included.

⁴

Based on 9.45 fb${}^{-1}$ of data, using neural networks to separate signal from backgrounds. The result is for ${\mathit m}_{{{\mathit t}}}$ = 172.5 GeV. Combination of this result with the CDF measurement in the 1 lepton channel AALTONEN 2014L gives $1.36$ ${}^{+0.37}_{-0.32}$ pb, consistent with the SM prediction, and is 4.2 sigma away from the background only hypothesis.

⁵	Based on 9.4 fb${}^{-1}$ of data, using neural networks to separate signal from backgrounds. The result is for ${\mathit m}_{{{\mathit t}}}$ = 172.5 GeV. The result is 3.8 sigma away from the background only hypothesis.

⁶

Based on 9.7 fb${}^{-1}$ of data per experiment. The result is for ${\mathit m}_{{{\mathit t}}}$ = 172.5 GeV, and is a combination of the CDF measurements AALTONEN 2014L, AALTONEN 2014K and the D0 measurement ABAZOV 2013O on the ${{\mathit s}}$-channel single ${{\mathit t}}$-quark production cross section. The result is consistent with the SM prediction of $1.05$ $\pm0.06$ pb and the significance of the observation is of 6.3 standard deviations.

⁷

Based on 7.5 fb${}^{-1}$ of data. Neural network is used to discriminate signals (${{\mathit s}}$-, ${{\mathit t}}$- and ${{\mathit W}}{{\mathit t}}$-channel single top production) from backgrounds. The result is consistent with the SM prediction, and gives $\vert \mathit V_{\mathit tb}\vert $ = $0.95$ $\pm0.09$(stat + syst)$\pm0.05$(theory) and $\vert \mathit V_{\mathit tb}\vert $ $>$ 0.78 (95$\%$ CL). The result is for ${\mathit m}_{{{\mathit t}}}$ = 172.5 GeV.

⁸

Based on 9.7 fb${}^{-1}$ of data. Events with ${{\mathit \ell}}$ + $\not E_T$ + 2 or 3 jets (1 or 2 ${{\mathit b}}$-tag) are analysed, assuming ${\mathit m}_{{{\mathit t}}}$ = 172.5 GeV. The combined s- + t-channel cross section gives $\vert V_{tb}{{\mathit f}_{{{1}}}^{L}}\vert $ = $1.12$ ${}^{+0.09}_{-0.08}$, or $\vert \mathit V_{\mathit tb}\vert $ $>$ 0.92 at 95$\%$ CL for ${{\mathit f}_{{{1}}}^{L}}$ = 1 and a flat prior within 0${}\leq{}$ $\vert V_{tb}\vert ^2$ ${}\leq{}$ 1.

⁹	Based on 5.4 fb${}^{-1}$ of data. The error is statistical + systematic combined. The results are for ${\mathit m}_{{{\mathit t}}}$ = 172.5 GeV. Results for other ${\mathit m}_{{{\mathit t}}}$ values are given in Table 2 of ABAZOV 2011AA.

¹⁰

Based on 5.4 fb${}^{-1}$ of data and for ${\mathit m}_{{{\mathit t}}}$ = 172.5 GeV. The error is statistical + systematic combined. Results for other ${\mathit m}_{{{\mathit t}}}$ values are given in Table III of ABAZOV 2011AD. The result is obtained by assuming the SM ratio between ${{\mathit t}}{{\mathit b}}$ (${{\mathit s}}$-channel) and ${{\mathit t}}{{\mathit q}}{{\mathit b}}$ (${{\mathit t}}$-channel) productions, and gives $\vert V_{tb}{{\mathit f}_{{{1}}}^{L}}\vert $ = $1.02$ ${}^{+0.10}_{-0.11}$, or $\vert V_{tb}\vert $ $>$ 0.79 at 95$\%$ CL for a flat prior within 0 $<$ $\vert V_{tb}\vert ^2$ $<$ 1.

¹¹	Based on 3.2 fb${}^{-1}$ of data. For combined ${{\mathit s}}$- + ${{\mathit t}}$-channel result see AALTONEN 2009AT.

¹²

Result is based on 2.1 fb${}^{-1}$ of data. Events with large missing $\mathit E_{T}$ and jets with at least one ${{\mathit b}}$-jet without identified electron or muon are selected. Result is obtained when observed 2.1 $\sigma $ excess over the background originates from the signal for ${\mathit m}_{{{\mathit t}}}$ = 175 GeV, giving $\vert \mathit V_{\mathit tb}\vert $ = $1.24$ ${}^{+0.34}_{-0.29}$ $\pm0.07$(theory).

¹³	Result is based on 2.3 fb${}^{-1}$ of data. Events with isolated ${{\mathit \ell}}$ + $\not E_T$ + 2 , 3, 4 jets with one or two ${{\mathit b}}$-tags are selected. The analysis assumes ${\mathit m}_{{{\mathit t}}}$ = 170 GeV.

¹⁴

Result is based on 4.8 fb${}^{-1}$ of data. Events with an isolated reconstructed tau lepton, missing $\mathit E_{T}$ + 2, 3 jets with one or two ${\mathit {\mathit b}}$-tags are selected. When combined with ABAZOV 2009Z result for ${{\mathit e}}{+}$ ${{\mathit \mu}}$ channels, the $\mathit s$- and $\mathit t$-channels combined cross section is $3.84$ ${}^{+0.89}_{-0.83}$ pb.

¹⁵

Based on 3.2 fb${}^{-1}$ of data. Events with isolated ${{\mathit \ell}}$ + $\not E_T$ + jets with at least one ${{\mathit b}}$-tag are analyzed and ${{\mathit s}}$- and ${{\mathit t}}$-channel single top events are selected by using the likelihood function, matrix element, neural-network, boosted decision tree, likelihood function optimized for ${{\mathit s}}$-channel process, and neural-networked based analysis of events with $\not E_T$ that has sensitivity for ${{\mathit W}}$ $\rightarrow$ ${{\mathit \tau}}{{\mathit \nu}}$ decays. The result is for ${\mathit m}_{{{\mathit t}}}$ = 175 GeV, and the mean value decreases by 0.02 pb/GeV for smaller ${\mathit m}_{{{\mathit t}}}$. The signal has 5.0 sigma significance. The result gives $\vert \mathit V_{\mathit tb}\vert $ = $0.91$ $\pm0.11$ (stat+syst)$\pm0.07$ (theory), or $\vert \mathit V_{\mathit tb}\vert $ $>$ 0.71 at 95$\%$ CL.

¹⁶

Based on 2.3 fb${}^{-1}$ of data. Events with isolated ${{\mathit \ell}}$ + $\not E_T$ +${}\geq{}$2 jets with 1 or 2 ${{\mathit b}}$-tags are analyzed and ${{\mathit s}}$- and ${{\mathit t}}$-channel single top events are selected by using boosted decision tree, Bayesian neural networks and the matrix element method. The signal has 5.0 sigma significance. The result gives $\vert \mathit V_{\mathit tb}\vert $ = $1.07$ $\pm0.12$ , or $\vert \mathit V_{\mathit tb}\vert $ $>$ 0.78 at 95$\%$ CL. The analysis assumes ${\mathit m}_{{{\mathit t}}}$ = 170 GeV.

¹⁷

Result is based on 2.2 fb${}^{-1}$ of data. Events with isolated ${{\mathit \ell}}$ + $\not E_T$ + 2, 3 jets with at least one ${{\mathit b}}$-tag are selected, and ${{\mathit s}}$- and ${{\mathit t}}$-channel single top events are selected by using likelihood, matrix element, and neural network discriminants. The result can be interpreted as $\vert \mathit V_{\mathit tb}\vert $ = $0.88$ ${}^{+0.13}_{-0.12}$(stat + syst)$\pm0.07$(theory), and $\vert \mathit V_{\mathit tb}\vert $ $>$ 0.66 (95$\%$ CL) under the $\vert \mathit V_{\mathit tb}\vert $ $<$ 1 constraint.

¹⁸

Result is based on 0.9 fb${}^{-1}$ of data. Events with isolated ${{\mathit \ell}}$ + $\not E_T$ + 2, 3, 4 jets with one or two ${{\mathit b}}$-vertex-tag are selected, and contributions from ${{\mathit W}}$ + jets, ${{\mathit t}}{{\overline{\mathit t}}}$, ${{\mathit s}}$- and ${{\mathit t}}$-channel single top events are identified by using boosted decision trees, Bayesian neural networks, and matrix element analysis. The result can be interpreted as the measurement of the CKM matrix element $\vert \mathit V_{\mathit tb}\vert $ = $1.31$ ${}^{+0.25}_{-0.21}$, or $\vert \mathit V_{\mathit tb}\vert $ $>$ 0.68 (95$\%$ CL) under the $\vert \mathit V_{\mathit tb}\vert $ $<$ 1 constraint.

¹⁹	Result is based on 0.9 fb${}^{-1}$ of data. This result constrains $\mathit V_{\mathit tb}$ to 0.68 $<$ $\vert \mathit V_{\mathit tb}\vert $ ${}\leq{}$ 1 at 95$\%$ CL.

²⁰

ABAZOV 2005P bounds single top-quark production from either the ${{\mathit s}}$-channel ${{\mathit W}}$-exchange process, ${{\mathit q}^{\,'}}$ ${{\overline{\mathit q}}}$ $\rightarrow$ ${{\mathit t}}{{\overline{\mathit b}}}$, or the ${{\mathit t}}$-channel ${{\mathit W}}$-exchange process, ${{\mathit q}^{\,'}}$ ${{\mathit g}}$ $\rightarrow$ ${{\mathit q}}{{\mathit t}}{{\overline{\mathit b}}}$, based on $\sim{}230~$pb${}^{-1}$ of data.

²¹

ACOSTA 2005N bounds single top-quark production from the ${{\mathit t}}$-channel ${{\mathit W}}$-exchange process ( ${{\mathit q}^{\,'}}$ ${{\mathit g}}$ $\rightarrow$ ${{\mathit q}}{{\mathit t}}{{\overline{\mathit b}}}$), the ${{\mathit s}}$-channel ${{\mathit W}}$-exchange process ( ${{\mathit q}^{\,'}}$ ${{\overline{\mathit q}}}$ $\rightarrow$ ${{\mathit t}}{{\overline{\mathit b}}}$), and from the combined cross section of ${{\mathit t}}$- and ${{\mathit s}}$-channel. Based on $\sim{}$ 162 pb${}^{-1}$ of data.

Except where otherwise noted, content of the 2024 Review of Particle Physics is licensed under a Creative Commons Attribution 4.0 International (CC BY 4.0) license. The publication of the Review of Particle Physics is supported by US DOE, MEXT (Japan), INFN (Italy) and CERN. Individual collaborators receive support for their PDG activities from their respective institutes or funding agencies. © 2024. See LBNL disclaimers.