OTHER ${{\mathit H}}$ PRODUCTION PROPERTIES

Higgs trilinear self coupling modifier ${{\mathit \kappa}_{{{\lambda}}}}$ INSPIRE search

Signal strength relative to the SM prediction, $\kappa _{\lambda }$ = ${{\mathit \kappa}_{{{3}}}}$ = $\lambda _{{{\mathit H}} {{\mathit H}} {{\mathit H}}}$ $/$ $\lambda {}^{{\mathrm {SM}}}_{{{\mathit H}} {{\mathit H}} {{\mathit H}}}$.
S126KLA
VALUE CL% DOCUMENT ID TECN  COMMENT
$3.8$ ${}^{+2.1}_{-3.6}$ 1
AAD
2024BL
ATLS 13 TeV, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \gamma}}{{\mathit \gamma}}$, multilepton , ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \ell}}{{\mathit \ell}}$
• • • We do not use the following data for averages, fits, limits, etc. • • •
$-11\text{ to }17 $ 95 2
AAD
2025J
ATLS 13 TeV, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$
$-1.2\text{ to }7.5 $ 95 3
HAYRAPETYAN
2025F
CMS 13 TeV, single and double Higgs production
$-3.1\text{ to }9.0 $ 95 4
AAD
2024AZ
ATLS 13 TeV, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$
$-6.2\text{ to }11.6 $ 95 5
AAD
2024BG
ATLS 13 TeV, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit Z}}{{\mathit Z}^{*}}$, ${{\mathit V}}{{\mathit V}}{{\mathit V}}{{\mathit V}}$, ${{\mathit V}}{{\mathit V}}{{\mathit \tau}}{{\mathit \tau}}$, ${{\mathit \tau}}{{\mathit \tau}}{{\mathit \tau}}{{\mathit \tau}}$, ${{\mathit \gamma}}{{\mathit \gamma}}{{\mathit V}}{{\mathit V}}$, ${{\mathit \gamma}}{{\mathit \gamma}}{{\mathit \tau}}{{\mathit \tau}}$
$-1.2\text{ to }7.2 $ 95 1
AAD
2024BL
ATLS 13 TeV, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \gamma}}{{\mathit \gamma}}$, multilepton , ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \ell}}{{\mathit \ell}}$
$-1.4\text{ to }6.9 $ 95 6
AAD
2024X
ATLS 13 TeV, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \gamma}}{{\mathit \gamma}}$
$-6.2\text{ to }13.3 $ 95 7
AAD
2024Y
ATLS 13 TeV, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit W}}{{\mathit W}^{*}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit Z}}{{\mathit Z}^{*}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$, multilepton
$-7.2\text{ to }13.8 $ 95 8
HAYRAPETYAN
2024AE
CMS 13 TeV, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit W}}{{\mathit W}^{*}}$
$-37.7\text{ to }37.2 $ 95 9
HAYRAPETYAN
2024AW
CMS 13 TeV, ${{\mathit V}}{{\mathit H}}{{\mathit H}}$, ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$
$-34.4\text{ to }33.3 $ 95 10
AAD
2023AD
ATLS 13 TeV, ${{\mathit V}}{{\mathit H}}{{\mathit H}}$, ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$
$-0.6\text{ to }6.6 $ 95 11
AAD
2023AT
ATLS 13 TeV, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \gamma}}{{\mathit \gamma}}$
$-0.4\text{ to }6.3 $ 95 12
AAD
2023AT
ATLS 13 TeV, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \gamma}}{{\mathit \gamma}}$
$-3.5\text{ to }11.3 $ 95 13
AAD
2023BK
ATLS 13 TeV, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$
$-5.4\text{ to }14.9 $ 95 14
HAYRAPETYAN
2023
CMS 13 TeV, ${{\mathit Z}}$ ${{\mathit Z}^{*}}$ $\rightarrow$ 4 ${{\mathit \ell}}$ cross sections
$-9.9\text{ to }16.9 $ 95 15
TUMASYAN
2023AE
CMS 13 TeV, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$
$-1.7\text{ to }8.7 $ 95 16
TUMASYAN
2023D
CMS 13 TeV, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$
$-8.8\text{ to }13.4 $ 95 17
TUMASYAN
2023I
CMS 13 TeV, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit Z}}{{\mathit Z}^{*}}$ ( ${{\mathit Z}}$ ${{\mathit Z}^{*}}$ $\rightarrow$ 4 ${{\mathit \ell}}$)
$-6.9\text{ to }11.1 $ 95 18
TUMASYAN
2023O
CMS 13 TeV, ${{\mathit W}}{{\mathit W}^{*}}{{\mathit W}}{{\mathit W}^{*}}$, ${{\mathit W}}{{\mathit W}^{*}}{{\mathit \tau}}{{\mathit \tau}}$, ${{\mathit \tau}}{{\mathit \tau}}{{\mathit \tau}}{{\mathit \tau}}$
$-1.5\text{ to }6.7 $ 95 19
AAD
2022Y
ATLS 13 TeV, ${{\mathit \gamma}}{{\mathit \gamma}}{{\mathit b}}{{\overline{\mathit b}}}$
$-1.24\text{ to }6.49 $ 95 20
CMS
2022
CMS 13 TeV, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit Z}}{{\mathit Z}^{*}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \gamma}}{{\mathit \gamma}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$, multilepton
$-2.3\text{ to }9.4 $ 95 21
TUMASYAN
2022AN
CMS 13 TeV, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$
$-3.3\text{ to }8.5 $ 95 22
SIRUNYAN
2021K
CMS 13 TeV, ${{\mathit \gamma}}{{\mathit \gamma}}{{\mathit b}}{{\overline{\mathit b}}}$
$-5.0\text{ to }12.0 $ 95 23
AAD
2020C
ATLS 13 TeV, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \gamma}}{{\mathit \gamma}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit W}}{{\mathit W}^{*}}$, ${{\mathit W}}{{\mathit W}^{*}}{{\mathit \gamma}}{{\mathit \gamma}}$, ${{\mathit W}}{{\mathit W}^{*}}{{\mathit W}}{{\mathit W}^{*}}$
$-11\text{ to }17 $ 95 24
SIRUNYAN
2019
CMS 13 TeV, ${{\mathit \gamma}}{{\mathit \gamma}}{{\mathit b}}{{\overline{\mathit b}}}$
$-11.8\text{ to }18.8 $ 95 25
SIRUNYAN
2019BE
CMS 13 TeV, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \gamma}}{{\mathit \gamma}}$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit W}}{{\mathit W}^{*}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit Z}}{{\mathit Z}^{*}}$
$-8.2\text{ to }13.2 $ 95 26
AABOUD
2018CW
ATLS 13 TeV, ${{\mathit \gamma}}{{\mathit \gamma}}{{\mathit b}}{{\overline{\mathit b}}}$
27
SIRUNYAN
2018A
CMS 13 TeV, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$
$-17\text{ to }22.5 $ 95 28
KHACHATRYAN
2016BQ
CMS 8 TeV, ${{\mathit \gamma}}{{\mathit \gamma}}{{\mathit b}}{{\overline{\mathit b}}}$
1  AAD 2024BL combine results from $126 - 140$ fb${}^{-1}$ of data at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV for ${{\mathit p}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit H}}{{\mathit H}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$ (AAD 2023BK, AAD 2024BV), ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$ (AAD 2024AZ), ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \gamma}}{{\mathit \gamma}}$ (AAD 2024X), multilepton (AAD 2024BG), and ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \ell}}{{\mathit \ell}}$ (AAD 2024Y). See their Fig. 3. All other Higgs couplings are fixed to the SM values.
2  AAD 2025J search for non-resonant ${{\mathit H}}{{\mathit H}}{{\mathit H}}$ production using ${{\mathit H}}$ ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$ with data of 126 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. Two-dimensional likelihood scan of (${{\mathit \kappa}_{{{3}}}}$ (=${{\mathit \kappa}_{{{\lambda}}}}$), ${{\mathit \kappa}_{{{4}}}}$) is shown in their Fig. 9. The quoted values are obtained by assuming ${{\mathit \kappa}_{{{4}}}}$ = 1. Note that the quoted values are calculated using the kappa framework, which outside the unitarity bounds requires additional modification to preserve unitarity for their results.
3  HAYRAPETYAN 2025F constrain the Higgs trilinear self-coupling using single and double Higgs production with data at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. The production modes and decay channels used are listed in their Tables 1 and 2 for single- and double-Higgs, respectively. Only single- and double-Higgs channels give $-1.8$ $<$ ${{\mathit \kappa}_{{{\lambda}}}}$ $<$ $12.0$ and $-1.7$ $<$ ${{\mathit \kappa}_{{{\lambda}}}}$ $<$ $7.0$, respectively. All the other Higgs boson couplings are fixed to their SM values. Their Table 3 shows results with some of the couplings are loosened. Two-dimensional likelihood scan of (${{\mathit \kappa}_{{{\lambda}}}}$, ${{\mathit \kappa}_{{{t}}}}$) is shown in their Fig. 5.
4  AAD 2024AZ search for non-resonant ${{\mathit H}}{{\mathit H}}$ production using ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$ with data of 140 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. Two-dimensional exclusion regions as a function of the ${{\mathit \kappa}_{{{\lambda}}}}$ and ${{\mathit \kappa}_{{{2V}}}}$ couplings are shown in their Fig. 9. All other Higgs couplings are fixed to the SM values.
5  AAD 2024BG search for non-resonant ${{\mathit H}}{{\mathit H}}$ production targeting the ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit Z}}{{\mathit Z}^{*}}$, ${{\mathit V}}{{\mathit V}}{{\mathit V}}{{\mathit V}}$, ${{\mathit V}}{{\mathit V}}{{\mathit \tau}}{{\mathit \tau}}$, ${{\mathit \tau}}{{\mathit \tau}}{{\mathit \tau}}{{\mathit \tau}}$, ${{\mathit \gamma}}{{\mathit \gamma}}{{\mathit V}}{{\mathit V}}$, ${{\mathit \gamma}}{{\mathit \gamma}}{{\mathit \tau}}{{\mathit \tau}}$ decay channels with data of 140 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. The limits are obtained with the values of all other couplings fixed to their SM value.
6  AAD 2024X search for non-resonant ${{\mathit H}}{{\mathit H}}$ production using ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \gamma}}{{\mathit \gamma}}$ with data of 140 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. Two-dimensional exclusion regions as a function of the $\kappa _{\lambda }$ and $\kappa _{2V}$ couplings are shown in their Fig. 6. All other Higgs couplings are fixed to the SM values.
7  AAD 2024Y search for non-resonant ${{\mathit H}}{{\mathit H}}$ production in 2 ${{\mathit b}}{+}$ 2 ${{\mathit \ell}}{+}$ ${{\mathit \nu}}$s final state (${{\mathit \ell}}$ = ${{\mathit e}}$ , ${{\mathit \mu}}$) targeting ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit W}}{{\mathit W}^{*}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit Z}}{{\mathit Z}^{*}}$, and ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$ decay channels with data of 140 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. All other coupling modifiers are set to their SM values.
8  HAYRAPETYAN 2024AE search for non-resonant ${{\mathit H}}{{\mathit H}}$ production using ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit W}}{{\mathit W}^{*}}$ with data of 138 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. Two-dimensional exclusion regions as a function of the ($\kappa _{\lambda }$, $\kappa _{2V}$) and ($\kappa _{\lambda }$, $\kappa _{t}$) are shown in their Figs. 13 and 15. All other Higgs couplings are fixed to the SM values.
9  HAYRAPETYAN 2024AW search for non-resonant ${{\mathit H}}{{\mathit H}}$ production in association with a vector boson using ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$ with data of 138 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. The vector boson decays both leptonically ( ${{\mathit W}}$ $\rightarrow$ ${{\mathit \ell}}{{\mathit \nu}}$, ${{\mathit Z}}$ $\rightarrow$ ${{\mathit \ell}}{{\mathit \ell}}$, ${{\mathit \nu}}{{\mathit \nu}}$, ${{\mathit \ell}}$ = ${{\mathit e}}$ , ${{\mathit \mu}}$) and hadronically. All other Higgs couplings are fixed to the SM values. Two-dimensional exclusion regions as a function of the $\kappa _{2V}$ and $\kappa _{\lambda }$ parameters are shown in their Fig. 14, with other couplings fixed to the SM values. The best fit value is ($\kappa _{\lambda }$, $\kappa _{2V}$) = (-2.6, 10.1).
10  AAD 2023AD search for non-resonant ${{\mathit H}}{{\mathit H}}$ production in association with a vector boson using ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$ with data of 139 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. The vector boson decays leptonically ( ${{\mathit W}}$ $\rightarrow$ ${{\mathit \ell}}{{\mathit \nu}}$, ${{\mathit Z}}$ $\rightarrow$ ${{\mathit \ell}}{{\mathit \ell}}$, ${{\mathit \nu}}{{\mathit \nu}}$, ${{\mathit \ell}}$ = ${{\mathit e}}$ , ${{\mathit \mu}}$). The quoted $\kappa _{\lambda }$ is measured assuming all other Higgs boson couplings are at their SM value.
11  AAD 2023AT combine results from $126 - 139$ fb${}^{-1}$ of data at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV for ${{\mathit p}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit H}}{{\mathit H}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$ (AAD 2023BK), ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$ (AAD 2023Z), and ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \gamma}}{{\mathit \gamma}}$ (AAD 2022Y). The quoted values are obtained from the profile likelihood scan as a function of $\kappa _{\lambda }$ as shown in their Fig. 5(a). All other coupling modifiers are assumed to have their SM values.
12  AAD 2023AT combine results from $126 - 139$ fb${}^{-1}$ of data at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV for ${{\mathit p}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit H}}{{\mathit H}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$ (AAD 2023BK), ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$ (AAD 2023Z), and ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \gamma}}{{\mathit \gamma}}$ (AAD 2022Y) with single-Higgs boson analyses (${{\mathit \gamma}}{{\mathit \gamma}}$, ${{\mathit Z}}{{\mathit Z}^{*}}$, ${{\mathit W}}{{\mathit W}^{*}}$, ${{\mathit \tau}}{{\mathit \tau}}$, ${{\mathit b}}{{\overline{\mathit b}}}$, see their Table 1). The quoted values are obtained from the profile likelihood scan as a function of $\kappa _{\lambda }$ as shown in their Fig. 5(a), assuming that all other Higgs boson couplings are at their SM values. Results with other assumptions are shown in their Table 2.
13  AAD 2023BK search for non-resonant ${{\mathit H}}{{\mathit H}}$ production using ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$ with data of 126 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. The quoted values are obtained from the one-dimensional profile likelihood scan as a function of $\kappa _{\lambda }$. See their Fig. 12 (a). The $\mu _{ggF+VBF}$ measurement for different values of $\kappa _{\lambda }$ constrains -3.9 $<$ $\kappa _{\lambda }$ $<$ 11.1 at 95$\%$ CL as shown in their Fig. 10 (a). $\kappa _{2V}$= $\kappa _{V}$=1 is assumed in both cases.
14  HAYRAPETYAN 2023 measure the cross sections for ${{\mathit p}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit Z}}{{\mathit Z}^{*}}$ $\rightarrow$ 4 ${{\mathit \ell}}$ (${{\mathit \ell}}$ = ${{\mathit e}}$ , ${{\mathit \mu}}$) using 138 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV.
15  TUMASYAN 2023AE search for ${{\mathit H}}{{\mathit H}}$ production using ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$, where both ${{\mathit b}}{{\overline{\mathit b}}}$ pairs are highly boosted, with data of 138 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. The quoted $\kappa _{\lambda }$ is measured assuming all other Higgs boson couplings are at their SM values.
16  TUMASYAN 2023D search for non-resonant ${{\mathit H}}{{\mathit H}}$ production using ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$ with data of 138 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. The quoted values are obtained from the upper limit on the ${{\mathit H}}{{\mathit H}}$ production cross section times the ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$ branching fraction for different values of $\kappa _{\lambda }$. See their Fig. 8 (left). All other coupling modifiers are assumed to be 1. In addition, two-dimensional exclusion regions as a function of the $\kappa _{\lambda }$ and $\kappa _{t}$ couplings, with $\kappa _{2V}$ = $\kappa _{V}$ = 1, are shown in their Fig. 9 (left). The one-dimensional likelihood scan as a function of $\kappa _{\lambda }$ is given in their Fig 10 (left), from which a 95$\%$ confidence interval of -1.77 $<$ $\kappa _{\lambda }$ $<$ 8.73 is extracted.
17  TUMASYAN 2023AI search for non-resonant ${{\mathit H}}{{\mathit H}}$ production using ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit Z}}{{\mathit Z}^{*}}$ ( ${{\mathit Z}}$ ${{\mathit Z}^{*}}$ $\rightarrow$ 4 ${{\mathit \ell}}$, ${{\mathit \ell}}={{\mathit e}},{{\mathit \mu}}$) with data of 138 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. See their Fig. 4.
18  TUMASYAN 2023O search for non-resonant ${{\mathit H}}{{\mathit H}}$ production using ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit W}}{{\mathit W}^{*}}{{\mathit W}}{{\mathit W}^{*}}$, ${{\mathit W}}{{\mathit W}^{*}}{{\mathit \tau}}{{\mathit \tau}}$, and ${{\mathit \tau}}{{\mathit \tau}}{{\mathit \tau}}{{\mathit \tau}}$ (multilepton) with data of 138 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. See their Fig. 10 for different final states and these combination. Limits are set on a variety of new-physics models using an effective field theory approach. See their Figs. 11, 12, and 13.
19  AAD 2022Y search for non-resonant ${{\mathit H}}{{\mathit H}}$ production using ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}{{\mathit b}}{{\overline{\mathit b}}}$ with data of 139 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. The quoted ${{\mathit \kappa}_{{{\lambda}}}}$ is obtained from their Fig. 12 where the theory uncertainties are not included while a negative log-likelihood scan vs. ${{\mathit \kappa}_{{{\lambda}}}}$is shown in their Fig. 13 with the theory uncertainties, which provides ${{\mathit \kappa}_{{{\lambda}}}}$ = $2.8$ ${}^{+2.0}_{-2.2}$ for the 1$\sigma $ confidence interval.
20  CMS 2022 report combined results (see their Extended Data Table 2) using 138 fb${}^{-1}$ of data at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. See their Fig. 6 (left).
21  TUMASYAN 2022AN search for non-resonant ${{\mathit H}}{{\mathit H}}$ production using ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$ with data of 138 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. The upper limit on the ${{\mathit p}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit H}}{{\mathit H}}$ production cross section at 95$\%$ CL is shown as a function of $\kappa _{\lambda }$ in their Fig. 2 (top).
22  SIRUNYAN 2021K search for non-resonant ${{\mathit H}}{{\mathit H}}$ production using ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}{{\mathit b}}{{\overline{\mathit b}}}$ with data of 137 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV.
23  AAD 2020C combine results of up to 36.1 fb${}^{-1}$ data at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV for ${{\mathit p}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit H}}{{\mathit H}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \gamma}}{{\mathit \gamma}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit b}}{{\overline{\mathit b}}}$, ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit W}}{{\mathit W}^{*}}$, ${{\mathit W}}{{\mathit W}^{*}}{{\mathit \gamma}}{{\mathit \gamma}}$, ${{\mathit W}}{{\mathit W}^{*}}{{\mathit W}}{{\mathit W}^{*}}$ (AABOUD 2018CW, AABOUD 2018CQ, AABOUD 2019A, AABOUD 2019O, AABOUD 2018BU, and AABOUD 2019T).
24  SIRUNYAN 2019 search for ${{\mathit H}}{{\mathit H}}$ production using ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}{{\mathit b}}{{\overline{\mathit b}}}$ with data of 35.9 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. The quoted $\kappa _{\lambda }$ is measured assuming all other Higgs boson couplings are at their SM value.
25  SIRUNYAN 2019BE combine results of 13 TeV 35.9 fb${}^{-1}$ data: SIRUNYAN 2019, SIRUNYAN 2018A, SIRUNYAN 2019AB, SIRUNYAN 2019H, and SIRUNYAN 2018F.
26  AABOUD 2018CW search for ${{\mathit H}}{{\mathit H}}$ production using ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}{{\mathit b}}{{\overline{\mathit b}}}$ with data of 36.1 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. The quoted $\kappa _{\lambda }$ is measured assuming all other Higgs boson couplings are at their SM value.
27  SIRUNYAN 2018A search for ${{\mathit H}}{{\mathit H}}$ production using ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}{{\mathit \tau}}{{\mathit \tau}}$ with data of 35.9 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. The upper limit on production cross section times branching fraction at 95$\%$ CL is shown as a function of $\kappa _{\lambda }/\kappa _{t}$ in their Fig. 6 (top) where $\kappa _{t}$ = ${{\mathit y}_{{{t}}}}$ $/$ ${{\mathit y}_{{{t}}}}{}^{SM}$ (top Yukawa coupling ${{\mathit y}_{{{t}}}}$).
28  KHACHATRYAN 2016BQ search for ${{\mathit H}}{{\mathit H}}$ production using ${{\mathit H}}$ ${{\mathit H}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}{{\mathit b}}{{\overline{\mathit b}}}$ with data of 19.7 fb${}^{-1}$ at $\mathit E_{{\mathrm {cm}}}$ = 8 TeV.
  References:
AAD 2025J
PR D111 032006 A search for triple Higgs boson production in the $6b$ final state using $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
HAYRAPETYAN 2025F
PL B861 139210 Constraints on the Higgs boson self-coupling from the combination of single and double Higgs boson production in proton-proton collisions at $\sqrt{s}$ = 13 TeV
AAD 2024Y
JHEP 2402 037 Search for non-resonant Higgs boson pair production in the $2b + 2\ell + E_\mathrm{T}^\mathrm{miss}$ final state in $pp$ collisions at $\sqrt{s} = 13\mathrm{TeV}$ with the ATLAS detector
AAD 2024BL
PRL 133 101801 Combination of searches for Higgs boson pair production in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
AAD 2024AZ
PR D110 032012 Search for the non-resonant production of Higgs boson pairs via gluon fusion and vector-boson fusion in the $b\bar{b}\tau^+\tau^-$ final state in proton-proton collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector
AAD 2024X
JHEP 2401 066 Studies of new Higgs boson interactions through nonresonant $HH$ production in the $b\bar{b}\gamma\gamma$ final state in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
AAD 2024BG
JHEP 2408 164 Search for non-resonant Higgs boson pair production in final states with leptons, taus, and photons in $pp$ collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector
HAYRAPETYAN 2024AE
JHEP 2407 293 Search for Higgs boson pair production in the $\mathrm{b}\overline{\mathrm{b}}$W$^+$W$^-$ decay mode in proton-proton collisions at $\sqrt{s}$ = 13 TeV
HAYRAPETYAN 2024AW
JHEP 2410 061 Search for Higgs boson pair production with one associated vector boson in proton-proton collisions at $\sqrt{s}$ = 13 TeV
AAD 2023AT
PL B843 137745 Constraining the Higgs boson self-coupling from single- and double-Higgs production with the ATLAS detector using $pp$ collisions at $\sqrt{s}=13$ TeV
AAD 2023AD
EPJ C83 519 Search for Higgs boson pair production in association with a vector boson in pp collisions at $\sqrt{s}=13\,\text {TeV}$ with the ATLAS detector
AAD 2023BK
PR D108 052003 Search for nonresonant pair production of Higgs bosons in the $b\bar{b}b\bar{b}$ final state in $pp$ collisions at $\sqrt{s}= 13$ TeV with the ATLAS detector
HAYRAPETYAN 2023
JHEP 2308 040 Measurements of inclusive and differential cross sections for the Higgs boson production and decay to four-leptons in proton-proton collisions at $\sqrt{s}$ = 13 TeV
TUMASYAN 2023O
JHEP 2307 095 Search for Higgs boson pairs decaying to WW*WW*, WW*$\tau\tau$, and $\tau\tau\tau\tau$ in proton-proton collisions at $\sqrt{s}$ = 13 TeV
TUMASYAN 2023AE
PRL 131 041803 Search for Nonresonant Pair Production of Highly Energetic Higgs Bosons Decaying to Bottom Quarks
TUMASYAN 2023I
JHEP 2306 130 Search for nonresonant Higgs boson pair production in the four leptons plus twob jets final state in proton-proton collisions at $ \sqrt{s} $ = 13 TeV
TUMASYAN 2023D
PL B842 137531 Search for nonresonant Higgs boson pair production in final state with two bottom quarks and two tau leptons in proton-proton collisions at s=13 TeV
AAD 2022Y
PR D106 052001 Search for Higgs boson pair production in the two bottom quarks plus two photons final state in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
CMS 2022
NAT 607 60 A portrait of the Higgs boson by the CMS experiment ten years after the discovery
TUMASYAN 2022AN
PRL 129 081802 Search for Higgs Boson Pair Production in the Four b Quark Final State in Proton-Proton Collisions at s=13??TeV
SIRUNYAN 2021K
JHEP 2103 257 Search for nonresonant Higgs boson pair production in final states with two bottom quarks and two photons in proton-proton collisions at $ \sqrt{s} $ = 13 TeV
AAD 2020C
PL B800 135103 Combination of searches for Higgs boson pairs in $pp$ collisions at $\sqrt{s} = $13 TeV with the ATLAS detector
SIRUNYAN 2019
PL B788 7 Search for Higgs boson pair production in the $\gamma\gamma\mathrm{b\overline{b}}$ final state in pp collisions at $\sqrt{s}=$ 13 TeV
SIRUNYAN 2019BE
PRL 122 121803 Combination of searches for Higgs boson pair production in proton-proton collisions at $\sqrt{s} = $ 13 TeV
AABOUD 2018CW
JHEP 1811 040 Search for Higgs boson pair production in the $\gamma\gamma b\bar{b}$ final state with 13 TeV $pp$ collision data collected by the ATLAS experiment
SIRUNYAN 2018A
PL B778 101 Search for Higgs Boson Pair Production in Events with Two Bottom Quarks and Two Tau Leptons in Proton-Proton Collisions at $\sqrt {s }$ = 13 TeV
KHACHATRYAN 2016BQ
PR D94 052012 Search for Two Higgs Bosons in Final States Containing Two Photons and Two Bottom Quarks in Proton-Proton Collisions at 8 TeV