MASS LIMITS FOR NEUTRAL HIGGS BOSONS IN EXTENDED HIGGS MODELS

This Section covers models which do not fit into either the Standard Model or its simplest minimal Supersymmetric extension (MSSM), leading to anomalous production rates, or nonstandard final states and branching ratios. In particular, this Section covers limits which may apply to generic two-Higgs-doublet models (2HDM), or to special regions of the MSSM parameter space where decays to invisible particles or to photon pairs are dominant (see the review on “Status of Higgs Boson Physics''). Concerning the mass limits for ${{\mathit H}^{0}}$ and ${{\mathit A}^{0}}$ listed below, see the footnotes or the comment lines for details on the nature of the models to which the limits apply.
The observed signal at about 125 GeV, see section “${{\mathit H}}$'', can be interpreted as one of the neutral Higgs bosons of an extended Higgs sector.

Mass Limits for ${{\mathit H}^{0}}$ with Vanishing Yukawa Couplings

INSPIRE   PDGID:
S055H2F
These limits assume that ${{\mathit H}^{0}}$ couples to gauge bosons with the same strength as the Standard Model Higgs boson, but has no coupling to quarks and leptons (this is often referred to as “fermiophobic'').
VALUE (GeV) CL% DOCUMENT ID TECN  COMMENT
• • We do not use the following data for averages, fits, limits, etc. • •
1
AALTONEN
2013K
 CDF ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit W}}{{\mathit W}^{(*)}}$
$\text{none 100 - 113}$ 95 2
AALTONEN
2013L
 CDF ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$, ${{\mathit W}}{{\mathit W}^{*}}$, ${{\mathit Z}}{{\mathit Z}^{*}}$
$\text{none 100 - 116}$ 95 3
AALTONEN
2013M
 TEVA ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$, ${{\mathit W}}{{\mathit W}^{*}}$, ${{\mathit Z}}{{\mathit Z}^{*}}$
4
ABAZOV
2013G
 D0 ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit W}}{{\mathit W}^{(*)}}$
$\text{none 100 - 113}$ 95 5
ABAZOV
2013H
 D0 ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$
6
ABAZOV
2013I
 D0 ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit W}}{{\mathit W}^{(*)}}$
7
ABAZOV
2013J
 D0 ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit W}}{{\mathit W}^{(*)}}$, ${{\mathit Z}}{{\mathit Z}^{(*)}}$
$\text{none 100 - 114}$ 95 8
ABAZOV
2013L
 D0 ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$, ${{\mathit W}}{{\mathit W}^{*}}$, ${{\mathit Z}}{{\mathit Z}^{*}}$
$\text{none 110 - 147}$ 95 9
CHATRCHYAN
2013AL
 CMS ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$
$\text{none 110 - 118, 119.5 - 121}$ 95 10
AAD
2012N
 ATLS ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$
$\text{none 100 - 114}$ 95 11
AALTONEN
2012AN
 CDF ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$
$\text{none 110 - 194}$ 95 12
CHATRCHYAN
2012AO
 CMS ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$, ${{\mathit W}}{{\mathit W}^{(*)}}$, ${{\mathit Z}}{{\mathit Z}^{(*)}}$
$\text{none 70 - 106}$ 95 13
AALTONEN
2009AB
 CDF ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$
$\text{none 70 - 100}$ 95 14
ABAZOV
2008U
 D0 ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$
$> 105.8$ 95 15
SCHAEL
2007
ALEP ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit H}^{0}}{{\mathit Z}}$, ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit W}}{{\mathit W}^{*}}$
$>104.1$ 95 16, 17
ABDALLAH
2004L
 DLPH ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit H}^{0}}{{\mathit Z}}$, ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$
$>107$ 95 18
ACHARD
2003C
 L3 ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit W}}{{\mathit W}^{*}},{{\mathit Z}}{{\mathit Z}^{*}}$, ${{\mathit \gamma}}{{\mathit \gamma}}$
$>105.5$ 95 16, 19
ABBIENDI
2002F
 OPAL ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$
$>105.4$ 95 20
ACHARD
2002C
 L3 ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$
$\text{none 60 - 82}$ 95 21
AFFOLDER
2001H
 CDF ${{\mathit p}}$ ${{\overline{\mathit p}}}$ $\rightarrow$ ${{\mathit H}^{0}}{{\mathit W}}$ $/$ ${{\mathit Z}}$, ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$
$>94.9$ 95 22
ACCIARRI
2000S
 L3 ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit H}^{0}}{{\mathit Z}}$, ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$
$>100.7$ 95 23
BARATE
2000L
 ALEP ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit H}^{0}}{{\mathit Z}}$, ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$
$>96.2$ 95 24
ABBIENDI
1999O
 OPAL ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit H}^{0}}{{\mathit Z}}$, ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$
$>78.5$ 95 25
ABBOTT
1999B
 D0 ${{\mathit p}}$ ${{\overline{\mathit p}}}$ $\rightarrow$ ${{\mathit H}^{0}}{{\mathit W}}$ $/$ ${{\mathit Z}}$, ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$
26
ABREU
1999P
 DLPH ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit H}^{0}}{{\mathit \gamma}}$ and/or ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$
1  AALTONEN 2013K search for ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit W}}{{\mathit W}^{(*)}}$ in 9.7 fb${}^{-1}$ of ${{\mathit p}}{{\overline{\mathit p}}}$ collisions at $\mathit E_{{\mathrm {cm}}}$ = 1.96 TeV. A limit on cross section times branching ratio which corresponds to ($1.3 - 6.6$) times the expected cross section is given in the range ${\mathit m}_{{{\mathit H}^{0}}}$ = $110 - 200$ GeV at 95$\%$ CL.
2  AALTONEN 2013L combine all CDF searches with $9.45 - 10.0$ fb${}^{-1}$ of ${{\mathit p}}{{\overline{\mathit p}}}$ collisions at $\mathit E_{{\mathrm {cm}}}$ = 1.96 TeV.
3  AALTONEN 2013M combine all Tevatron data from the CDF and D0 Collaborations of ${{\mathit p}}{{\overline{\mathit p}}}$ collisions at $\mathit E_{{\mathrm {cm}}}$ = 1.96 TeV.
4  ABAZOV 2013G search for ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit W}}{{\mathit W}^{(*)}}$ in 9.7 fb${}^{-1}$ of ${{\mathit p}}{{\overline{\mathit p}}}$ collisions at $\mathit E_{{\mathrm {cm}}}$ = 1.96 TeV. A limit on cross section times branching ratio which corresponds to ($2 - 9$) times the expected cross section is given for ${\mathit m}_{{{\mathit H}^{0}}}$ = $100 - 200$ GeV at 95$\%$ CL.
5  ABAZOV 2013H search for ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$ in 9.6 fb${}^{-1}$ of ${{\mathit p}}{{\overline{\mathit p}}}$ collisions at $\mathit E_{{\mathrm {cm}}}$ = 1.96 TeV.
6  ABAZOV 2013I search for ${{\mathit H}^{0}}$ production in the final state with one lepton and two or more jets plus missing $\mathit E_{T}$ in 9.7 fb${}^{-1}$ of ${{\mathit p}}{{\overline{\mathit p}}}$ collisions at $\mathit E_{{\mathrm {cm}}}$ = 1.96 TeV. The search is sensitive to ${{\mathit W}}{{\mathit H}^{0}}$, ${{\mathit Z}}{{\mathit H}^{0}}$ and vector-boson fusion Higgs production with ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit W}}{{\mathit W}^{(*)}}$. A limit on cross section times branching ratio which corresponds to ($8 - 30$) times the expected cross section is given in the range ${\mathit m}_{{{\mathit H}^{0}}}$ = $100 - 200$ GeV at 95$\%$ CL.
7  ABAZOV 2013J search for ${{\mathit H}^{0}}$ production in the final states ${{\mathit e}}{{\mathit e}}{{\mathit \mu}}$, ${{\mathit e}}{{\mathit \mu}}{{\mathit \mu}}$, ${{\mathit \mu}}{{\mathit \tau}}{{\mathit \tau}}$, and ${{\mathit e}^{\pm}}{{\mathit \mu}^{\pm}}$ in $8.6 - 9.7$ fb${}^{-1}$ of ${{\mathit p}}{{\overline{\mathit p}}}$ collisions at $\mathit E_{{\mathrm {cm}}}$ = 1.96 TeV. The search is sensitive to ${{\mathit W}}{{\mathit H}^{0}}$, ${{\mathit Z}}{{\mathit H}^{0}}$ production with ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit W}}{{\mathit W}^{(*)}}$, ${{\mathit Z}}{{\mathit Z}^{(*)}}$, decaying to leptonic final states. A limit on cross section times branching ratio which corresponds to ($2.4 - 13.0$) times the expected cross section is given in the range ${\mathit m}_{{{\mathit H}^{0}}}$ = $100 - 200$ GeV at 95$\%$ CL.
8  ABAZOV 2013L combine all D0 results with up to 9.7 fb${}^{-1}$ of ${{\mathit p}}{{\overline{\mathit p}}}$ collisions at $\mathit E_{{\mathrm {cm}}}$ = 1.96 TeV.
9  CHATRCHYAN 2013AL search for ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$ in 5.1 fb${}^{-1}$ and 5.3 fb${}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\mathit E_{{\mathrm {cm}}}$ = 7 and 8 TeV.
10  AAD 2012N search for ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$ with 4.9 fb${}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\mathit E_{{\mathrm {cm}}}$ = 7 TeV in the mass range ${\mathit m}_{{{\mathit H}^{0}}}$ = $110 - 150$ GeV.
11  AALTONEN 2012AN search for ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$ with 10 fb${}^{-1}$ of ${{\mathit p}}{{\overline{\mathit p}}}$ collisions at $\mathit E_{{\mathrm {cm}}}$ = 1.96 TeV in the mass range ${\mathit m}_{{{\mathit H}^{0}}}$ = $100 - 150$ GeV.
12  CHATRCHYAN 2012AO use data from CHATRCHYAN 2012G, CHATRCHYAN 2012E, CHATRCHYAN 2012H, CHATRCHYAN 2012I, CHATRCHYAN 2012D, and CHATRCHYAN 2012C.
13  AALTONEN 2009AB search for ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$ in 3.0 fb${}^{-1}$ of ${{\mathit p}}{{\overline{\mathit p}}}$ collisions at $\mathit E_{{\mathrm {cm}}}$ = 1.96 TeV in the mass range ${\mathit m}_{{{\mathit H}^{0}}}$ = $70 - 150$ GeV. Associated ${{\mathit H}^{0}}{{\mathit W}}$, ${{\mathit H}^{0}}{{\mathit Z}}$ production and ${{\mathit W}}{{\mathit W}}$, ${{\mathit Z}}{{\mathit Z}}$ fusion are considered.
14  ABAZOV 2008U search for ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$ in ${{\mathit p}}{{\overline{\mathit p}}}$ collisions at $\mathit E_{{\mathrm {cm}}}$ = 1.96 TeV in the mass range ${\mathit m}_{{{\mathit H}^{0}}}$ = $70 - 150$ GeV. Associated ${{\mathit H}^{0}}{{\mathit W}}$, ${{\mathit H}^{0}}{{\mathit Z}}$ production and ${{\mathit W}}{{\mathit W}}$, ${{\mathit Z}}{{\mathit Z}}$ fusion are considered. See their Tab. 1 for the limit on $\sigma \cdot{}$B( ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$), and see their Fig. 3 for the excluded region in the ${\mathit m}_{{{\mathit H}^{0}}}$ $-$ B( ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$) plane.
15  SCHAEL 2007 search for Higgs bosons in association with a fermion pair and decaying to ${{\mathit W}}{{\mathit W}^{*}}$. The limit is from this search and HEISTER 2002L for a ${{\mathit H}^{0}}$ with SM production cross section.
16  Search for associated production of a ${{\mathit \gamma}}{{\mathit \gamma}}$ resonance with a ${{\mathit Z}}~$boson, followed by ${{\mathit Z}}$ $\rightarrow$ ${{\mathit q}}{{\overline{\mathit q}}}$, ${{\mathit \ell}^{+}}{{\mathit \ell}^{-}}$, or ${{\mathit \nu}}{{\overline{\mathit \nu}}}$, at $\mathit E_{{\mathrm {cm}}}{}\leq{}$209 GeV. The limit is for a ${{\mathit H}^{0}}$ with SM production cross section.
17  Updates ABREU 2001F.
18  ACHARD 2003C search for ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}{{\mathit H}^{0}}$ followed by ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit W}}{{\mathit W}^{*}}$ or ${{\mathit Z}}{{\mathit Z}^{*}}$ at $\mathit E_{{\mathrm {cm}}}$= 200-209 GeV and combine with the ACHARD 2002C result. The limit is for a ${{\mathit H}^{0}}$ with SM production cross section. For B( ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit W}}{{\mathit W}^{*}}$) + B( ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit Z}}{{\mathit Z}^{*}}$) = 1, m$_{{{\mathit H}^{0}}}$ $>$ 108.1 GeV is obtained. See fig.$~$6 for the limits under different BR assumptions.
19  For B( ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$)=1, ${\mathit m}_{{{\mathit H}^{0}}}>$117 GeV is obtained.
20  ACHARD 2002C search for associated production of a ${{\mathit \gamma}}{{\mathit \gamma}}$ resonance with a ${{\mathit Z}}$ boson, followed by ${{\mathit Z}}$ $\rightarrow$ ${{\mathit q}}{{\overline{\mathit q}}}$, ${{\mathit \ell}^{+}}{{\mathit \ell}^{-}}$, or ${{\mathit \nu}}{{\overline{\mathit \nu}}}$, at $\mathit E_{{\mathrm {cm}}}{}\leq{}$209 GeV. The limit is for a ${{\mathit H}^{0}}$ with SM production cross section. For B( ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$)=1, ${\mathit m}_{{{\mathit H}^{0}}}>$114 GeV is obtained.
21  AFFOLDER 2001H search for associated production of a ${{\mathit \gamma}}{{\mathit \gamma}}$ resonance and a ${{\mathit W}}$ or ${{\mathit Z}}$ (tagged by two jets, an isolated lepton, or missing $\mathit E_{\mathit T}$). The limit assumes Standard Model values for the production cross section and for the couplings of the ${{\mathit H}^{0}}$ to ${{\mathit W}}$ and ${{\mathit Z}}$ bosons. See their Fig.$~$11 for limits with B( ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})<1$.
22  ACCIARRI 2000S search for associated production of a ${{\mathit \gamma}}{{\mathit \gamma}}$ resonance with a ${{\mathit q}}{{\overline{\mathit q}}}$, ${{\mathit \nu}}{{\overline{\mathit \nu}}}$, or ${{\mathit \ell}^{+}}{{\mathit \ell}^{-}}$ pair in ${{\mathit e}^{+}}{{\mathit e}^{-}}$ collisions at $\mathit E_{{\mathrm {cm}}}$= $189~$GeV. The limit is for a ${{\mathit H}^{0}}$ with SM production cross section. For B( ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$)=1, ${\mathit m}_{{{\mathit H}^{0}}}>98~$GeV is obtained. See their Fig.$~$5 for limits on B( ${{\mathit H}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})\cdot{}\sigma\mathrm {( {{\mathit e}^{+}} {{\mathit e}^{-}} \rightarrow {{\mathit H}} {{\mathit f}} {{\overline{\mathit f}}})}/\sigma\mathrm {( {{\mathit e}^{+}} {{\mathit e}^{-}} \rightarrow {{\mathit H}} {{\mathit f}} {{\overline{\mathit f}}})}$ (SM).
23  BARATE 2000L search for associated production of a ${{\mathit \gamma}}{{\mathit \gamma}}$ resonance with a ${{\mathit q}}{{\overline{\mathit q}}}$, ${{\mathit \nu}}{{\overline{\mathit \nu}}}$, or ${{\mathit \ell}^{+}}{{\mathit \ell}^{-}}$ pair in ${{\mathit e}^{+}}{{\mathit e}^{-}}$ collisions at $\mathit E_{{\mathrm {cm}}}$= $88 - 202~$GeV. The limit is for a ${{\mathit H}^{0}}$ with SM production cross section. For B( ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$)=1, ${\mathit m}_{{{\mathit H}^{0}}}>109~$GeV is obtained. See their Fig.$~$3 for limits on B( ${{\mathit H}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})\cdot{}\sigma\mathrm {( {{\mathit e}^{+}} {{\mathit e}^{-}} \rightarrow {{\mathit H}} {{\mathit f}} {{\overline{\mathit f}}})}/\sigma\mathrm {( {{\mathit e}^{+}} {{\mathit e}^{-}} \rightarrow {{\mathit H}} {{\mathit f}} {{\overline{\mathit f}}})}$ (SM).
24  search for associated production of a ${{\mathit \gamma}}{{\mathit \gamma}}$ resonance with a ${{\mathit q}}{{\overline{\mathit q}}}$, ${{\mathit \nu}}{{\overline{\mathit \nu}}}$, or ${{\mathit \ell}^{+}}{{\mathit \ell}^{-}}$ pair in ${{\mathit e}^{+}}{{\mathit e}^{-}}$ collisions at 189 GeV. The limit is for a ${{\mathit H}^{0}}$ with SM production cross section. See their Fig.$~$4 for limits on $\sigma\mathrm {( {{\mathit e}^{+}} {{\mathit e}^{-}} \rightarrow {{\mathit H}^{0}} {{\mathit Z}^{0}})}{\times }$B( ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}){\times }$B( ${{\mathit X}^{0}}$ $\rightarrow$ ${{\mathit f}}{{\overline{\mathit f}}}$) for various masses. Updates the results of ACKERSTAFF 1998Y.
25  ABBOTT 1999B search for associated production of a ${{\mathit \gamma}}{{\mathit \gamma}}$ resonance and a dijet pair. The limit assumes Standard Model values for the production cross section and for the couplings of the ${{\mathit H}^{0}}$ to ${{\mathit W}}$ and ${{\mathit Z}}$ bosons. Limits in the range of ${\mathit \sigma (}{{\mathit H}^{0}}+{{\mathit Z}}/{{\mathit W}}{)}\cdot{}$B( ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$)= $0.80 - 0.34~$pb are obtained in the mass range ${\mathit m}_{{{\mathit H}^{0}}}$= $65 - 150$ GeV.
26  ABREU 1999P search for ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit H}^{0}}{{\mathit \gamma}}$ with ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit b}}{{\overline{\mathit b}}}$ or ${{\mathit \gamma}}{{\mathit \gamma}}$, and ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit H}^{0}}{{\mathit q}}{{\overline{\mathit q}}}$ with ${{\mathit H}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$. See their Fig.$~$4 for limits on $\sigma {\times }$B. Explicit limits within an effective interaction framework are also given.
References