Limits from CDF and CMS are from ${{\mathit q}^{*}}{{\mathit q}^{*}}$ production via strong interactions. Other limits are mostly obtained from ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit q}^{*}}{{\overline{\mathit q}}^{*}}$ and thus rely only on the (electroweak) charge of the ${{\mathit q}^{*}}$. Form factor effects are ignored unless noted. Assumptions about the ${{\mathit q}^{*}}$ decay are given in the comments and footnotes.

S054EQP VALUE (GeV) CL% DOCUMENT ID TECN  COMMENT • • We do not use the following data for averages, fits, limits, etc. • • $>1050$ 95 1 HAYRAPETYAN 2025 AA   CMS ${{\mathit t}^{*}}$ $\rightarrow$ ${{\mathit t}}{{\mathit g}}$ $>1700$ 95 2 HAYRAPETYAN 2025 AA   CMS ${{\mathit p}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit t}_{{{3/2}}}^{*}}{{\overline{\mathit t}}_{{{3/2}}}^{*}}$ $\rightarrow$ ${{\mathit t}}{{\overline{\mathit t}}}{{\mathit g}}{{\mathit g}}$ $\text{none 700 - 1200}$ 95 3 SIRUNYAN 2018 V   CMS ${{\mathit p}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit t}_{{{3/2}}}^{*}}{{\overline{\mathit t}}_{{{3/2}}}^{*}}$ $\rightarrow$ ${{\mathit t}}{{\overline{\mathit t}}}{{\mathit g}}{{\mathit g}}$ $> 338$ 95 4 AALTONEN 2010 H   CDF ${{\mathit q}^{*}}$ $\rightarrow$ ${{\mathit t}}{{\mathit W}^{-}}$ 5 BARATE 1998 U   ALEP ${{\mathit Z}}$ $\rightarrow$ ${{\mathit q}^{*}}{{\mathit q}^{*}}$ $>45.6$ 95 6 ADRIANI 1993 M   L3 ${{\mathit u}}$ or ${{\mathit d}}$ type, ${{\mathit Z}}$ $\rightarrow$ ${{\mathit q}^{*}}{{\mathit q}^{*}}$ $>41.7$ 95 7 BARDADIN-OTWI.. 1992   RVUE ${{\mathit u}}$-type, $\Gamma\mathrm {({{\mathit Z}})}$ $>44.7$ 95 7 BARDADIN-OTWI.. 1992   RVUE ${{\mathit d}}$-type, $\Gamma\mathrm {({{\mathit Z}})}$ $>40.6$ 95 8 DECAMP 1992   ALEP ${{\mathit u}}$-type, $\Gamma\mathrm {({{\mathit Z}})}$ $>44.2$ 95 8 DECAMP 1992   ALEP ${{\mathit d}}$-type, $\Gamma\mathrm {({{\mathit Z}})}$ $>45$ 95 9 DECAMP 1992   ALEP ${{\mathit u}}$ or ${{\mathit d}}$ type, ${{\mathit Z}}$ $\rightarrow$ ${{\mathit q}^{*}}{{\mathit q}^{*}}$ $>45$ 95 8 ABREU 1991 F   DLPH ${\mathit {\mathit u}}$-type, $\Gamma\mathrm {({{\mathit Z}})}$ $>45$ 95 8 ABREU 1991 F   DLPH ${\mathit {\mathit d}}$-type, $\Gamma\mathrm {({{\mathit Z}})}$ 1  HAYRAPETYAN 2025AA search for pair production of vector-like ${{\mathit t}^{*}}$ in ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 13 TeV. ${{\mathit t}^{*}}$ is assumed to be an SU(2)$_{W}$ singlet decaying to ${{\mathit t}}{{\mathit g}}$. See their Fig. 7 for limits on $\sigma \cdot{}B{}^{2}$. 2  HAYRAPETYAN 2025AA search for pair production of spin 3/2 excited top quark ${{\mathit t}_{{{3/2}}}^{*}}$ in ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 13 TeV. See their Fig. 8 for limits on $\sigma \cdot{}B{}^{2}$. 3  SIRUNYAN 2018V search for pair production of spin 3/2 excited top quarks. B(${{\mathit t}_{{{3/2}}}^{*}}$ $\rightarrow$ ${{\mathit t}}{{\mathit g}}$) = 1 is assumed. 4  AALTONEN 2010H obtain limits on the ${{\mathit q}^{*}}{{\mathit q}^{*}}$ production cross section in ${{\mathit p}}{{\overline{\mathit p}}}$ collisions. See their Fig.$~$3. 5  BARATE 1998U obtain limits on the form factor. See their Fig.$~$16 for limits in mass-form factor plane. 6  ADRIANI 1993M limit is valid for B(${{\mathit q}^{*}}$ $\rightarrow$ ${{\mathit q}}{{\mathit g}})>0.25$ ($0.17$) for up (down) type. 7  BARDADIN-OTWINOWSKA 1992 limit based on $\Delta \Gamma\mathrm {({{\mathit Z}})}<$36 MeV. 8  These limits are independent of decay modes. 9  Limit is for B(${{\mathit q}^{*}}$ $\rightarrow$ ${{\mathit q}}{{\mathit g}})+B({{\mathit q}^{*}}$ $\rightarrow$ ${{\mathit q}}{{\mathit \gamma}}$)=1.

References