Higgs Branching Ratios in Constrained Minimal and Next-to-Minimal Supersymmetry Scenarios Surveyed

In the CMSSM the heaviest scalar and pseudo-scalar Higgs bosons decay largely into b-quarks and tau-leptons because of the large $\tan\beta$ values favored by the relic density. In the NMSSM the number of possible decay modes is much richer. In addition to the CMSSM-like scenarios, the decay of the heavy Higgs bosons is preferentially into top quark pairs (if kinematically allowed), lighter Higgs bosons or neutralinos, leading to invisible decays. We provide a scan over the NMSSM parameter space to project the 6D parameter space of the Higgs sector on the 3D space of the Higgs masses to determine the range of branching ratios as function of the Higgs boson mass for all Higgs bosons. Specific LHC benchmark points are proposed, which represent the salient NMSSM features.


Introduction
A light Higgs boson below 135 GeV is predicted within Supersymmetry (SUSY) [1][2][3]. So the discovery of a Higgs-like boson with a mass of 125 GeV [4,5] strongly supports SUSY although no SUSY particles have been found so far. The precise value of the Higgs mass depends on radiative corrections. Within the constrained minimal supersymmetric standard model (CMSSM) [6] the tree level Higgs boson mass is below the Z 0 -boson mass M Z (91 GeV) and to reach the observed mass of 125 GeV the radiative corrections from stop loops have to be large, see e.g. [7][8][9][10] and references therein. However, a 125 GeV Higgs boson is easily obtained in the minimal extension of the CMSSM where an additional Higgs singlet is introduced, since then the tree level value of the Higgs boson can be above M Z . The reason is simple: within the socalled next-to-minimal supersymmetric standard model (NMSSM) [11] the mixing with the additional Higgs singlet increases the Higgs mass at tree level [12][13][14][15][16][17][18][19], so the radiative corrections from the stop loops do not need multi-TeV stop squarks in the NMSSM, thus avoiding the fine-tuning problem [1][2][3]. The addition of a Higgs singlet yields more parameters in the Higgs sector to cope with the interactions between the singlet and the doublets and the singlet self interaction. Furthermore, the supersymmetric partner of the singlet leads to an additional Higgsino, thus extending the neutralino sector from 4 to 5 neutralinos. These additional particles and their interactions lead to a large parameter space, even if one considers the well-motivated subspace with unified masses and couplings at the GUT scale.
On the other hand, experiments are mostly interested in possible ranges of Higgs masses and branching ratios. With 5 neutral Higgs masses, of which one has to be 125 GeV and two of the heavy neutral Higgses masses are practically mass-degenerate, one is left with a 3-dimensional (3D) space in the Higgs masses in contrast to the 6-dimensional (6D) parameter space of the constrained Z 3 -invariant NMSSM Higgs sector. A certain point in the Higgs mass space can be obtained for several combinations of the 6D parameter space, which in turn leads to a range of branching ratios of the Higgs bosons.
In this paper we ventured to project the 6D parameter space on the 3D space of Higgs masses to obtain the expected range of branching ratios as function of the Higgs mass for each Higgs boson. This allows us to look for the distinctive features between the NMSSM and CMSSM. After a short summary of the Higgs and gaugino sectors in the CMSSM and NMSSM we discuss the fit strategy to project the 6D parameter space on the 3D neutral Higgs mass space. We conclude by summarizing the branching ratios of both models and selected benchmark points showing the salient features of the NMSSM.

NMSSM Higgs sector
We focus on the well-motivated semi-constrained next-to-minimal supersymmetric standard model (NMSSM), as described in Ref. [11] and use the corresponding code NMSSMTools 4.6.0 [20] to calculate the SUSY mass spectrum, Higgs boson masses and branching ratios from the NMSSM parameters.
Within the NMSSM the Higgs fields consist of the two Higgs doublets (H u , H d ), which appear in the MSSM as well, but together with an additional complex Higgs singlet S. In addition, we have the GUT scale parameters of the CMSSM: m 0 , m 1/2 and A 0 , where m 0 (m 1/2 ) are the common mass scales of the spin 0(1/2) SUSY particles at the GUT scale and A 0 is the trilinear coupling of the CMSSM Higgs sector at the GUT scale. In total the semiconstrained NMSSM has nine free parameters: Here tan β corresponds to the ratio of the vevs of the Higgs doublets, i.e. tan β ≡ v u /v d , λ represents the coupling between the Higgs singlet and doublets (λSH u · H d ), κ the self-coupling of the singlet (κS 3 /3); A λ and A κ are the corresponding trilinear soft breaking terms, µ ef f represents an effective Higgs mixing parameter and is related to the vev of the singlet s via the coupling λ, i.e. µ ef f ≡ λs. Therefore, µ ef f is naturally of the order of the electroweak scale, thus avoiding the µ-problem [11]. The latter six parameters in Eq. 1 form the 6D parameter space of the NMSSM Higgs sector. The neutral components from the two Higgs doublets and singlet mix to form three physical CP-even scaler (S) bosons and two physical CP-odd pseudo-scalar (P ) bosons.
The elements of the corresponding mass matrices at tree level read [21]: with the gaugino masses M 1 , M 2 , the gauge couplings g 1 , g 2 and the Higgs mixing parameter µ ef f as parameters. Furthermore, the vacuum expectation values of the two Higgs doublets v d ,v u , the singlet s and the Higgs couplings λ − κ enter the neutralino mass matrix. The upper 4 × 4 submatrix of the neutralino mixing matrix corresponds to the MSSM neutralino mass matrix, see e.g. Ref. [3]. Since the additional Higgs singlino affects only the neutral gaugino sector, the mixing matrix for the charginos in the NMSSM and CMSSM are identical: To obtain the mass eigenstates the mass matrices have to be diagonalized. Typically the diagonal elements in Eq. 5 and 6 dominate over the off-diagonal terms, so the neutralino masses are of the order of M 1 , M 2 , the Higgs mixing parameter µ ef f and in case of the NMSSM 2κ/λµ ef f . The chargino masses are of the order of M 2 and µ ef f .
Since we use GUT scale input parameters and the mass spectrum at the low mass SUSY scales is calculated via the renormalization group equations (RGEs), the masses are correlated. The gaugino masses are proportional to m 1/2 [1][2][3]: This leads to bino-like light neutralinos and wino-like light charginos in the CMSSM, since µ is typically much larger than m 1/2 to fulfill radiative electroweak symmetry breaking (EWSB) [1][2][3]. In the NMSSM µ ef f is an input parameter and it can be chosen such that it is of the order of the electroweak scale. This changes both the neutralino and chargino sector. In such natural NMSSM scenarios the lightest neutralino is singlino-like and its mass can be degenerate to the second/third neutralino and the lightest chargino, which all have a mass of the order of µ ef f .

Analysis
As discussed in sect. 2 the number of free parameters in the NMSSM increases with respect to the MSSM. Six of the nine free NMSSM parameters enter the Higgs sector. For each set of parameters the Higgs boson masses are completely determined: 3 scalar Higgs masses m H i , 2 pseudo-scalar Higgs 5 masses m A i and the charged Higgs boson mass m H ± . The index i increases with increasing mass. The masses of A 2 , H 3 and H ± are of the order of M A , if M A >> M Z . Then only one of the masses is needed. Furthermore, either H 1 or H 2 has to be the observed Higgs boson with a mass of 125 GeV, so there are only 3 free neutral Higgs boson masses in the NMSSM, i.e. a 3D parameter space, e.g m A 1 , m H 1 and m H 3 ≈ m A 2 ≈ m H ± . Instead of scanning over the 6D parameter space of the couplings to determine the range of Higgs boson masses, which was done by other groups in the MSSM [23,24], one can invert the problem and scan the 3D parameter space of the Higgs boson masses and check which region of the 6D parameter space leads to a given point in the 3D Higgs mass space.
We proceed as follows: we divide the m H 1 − m H 3 mass plane in a grid with fine mass bins for a certain value of m A 1 . These grids were repeated with the values of m A 1 varying between 25 and 500 GeV, while m H 1 ranges from 5 to 125 GeV in steps of 5 GeV. The heavy Higgs boson mass m H 3 was allowed to vary between 100 GeV and 2 TeV.
For each bin in each grid for a given m A 1 one can use Minuit [25] to determine the corresponding NMSSM parameters at the GUT scale using a χ 2 function, which reads: The χ 2 contributions are This term requires the NMSSM parameters to be adjusted such that the mass of the lightest Higgs boson mass m H 1 agrees with the chosen point in the 3D mass space m grid,H 1 . m H 1 has always a mass below the observed Higgs boson mass. The value of σ 2 H 1 is set to 2 GeV.
: since the lightest Higgs boson H 1 has a mass below 125 GeV, the second lightest Higgs boson has to represent the observed Higgs boson with couplings close to the SM couplings, as required by the last term. c i H 2 represents the reduced couplings of H 2 which is the ratio of the coupling of H 2 to particle i = f u , f d , W/Z, γ divided by the SM coupling. The observed couplings c obs agree within 10% with the SM couplings, so σ 2 coup = 0.1. The first term is analogous to the term for m H 1 , except that the mass of the second lightest Higgs boson should have the observed Higgs boson mass, so m obs is set to 125.2 GeV. The corresponding uncertainty σ 2 SM equals 1.9 GeV and results from the linear addition of the experimental and theoretical (1.5 GeV) uncertainties.
, but for the heavy scalar Higgs boson H 3 .
• χ 2 LEP : includes the LEP constraints on the couplings of a light Higgs boson below 115 GeV and the limit on the chargino mass as discussed in Ref. [26].
We allowed also the rare cases, where the lightest Higgs boson is the observed Higgs boson with SM-like couplings and m H 2 is above the observed mass (usually slightly). In addition, we checked what happens if one adds the cosmological constraints assuming the LSP (largely singlino) provides the relic density and gives a nucleon scattering cross section consistent with the direct DM searches. These dark matter constraints are calculated with micrOmegas [27], as interfaced within NMSSMTools.
In summary, the analysis looks like one has observed all Higgs boson masses and tries to infer the corresponding region of the 6D NMSSM parameter space with the option to include the cosmological constraints. From the allowed region of couplings in the 6D space one can then deduce the allowed range of branching ratios for the considered Higgs boson masses in the 3D mass space.
The determination of the 6D parameter set to obtain a certain Higgs mass combination is not unique, as can be easily seen already from the approximate expression for the 125 GeV Higgs boson [11]: The first two terms are identical to the CMSSM, where the first tree level term can become as large as M 2 Z for large tan β, but in the CMSSM the difference between M Z and 125 GeV has to originate mainly from the logarithmic stop mass corrections ∆t. The two remaining terms originate from the mixing with the singlet of the NMSSM and become large for large values of the couplings λ and κ and small tan β. This is what we call scenario I. However, the 125 GeV Higgs boson mass can also be reached by a trade-off between the first two CMSSM terms and last two NMSSM terms using smaller couplings and Table 1: The two main NMSSM scenarios corresponding to different ranges of the masses and couplings which are associated with different numbered benchmark points (BMP). The range of tan β is determined by the observed Higgs mass for a given range of the couplings κ and λ.

scenario
I II couplings tan β < 10 tan β > 10 λ, κ large λ, κ small larger tan β values. This is what we call scenario II. These scenarios have distinctly different signatures. In scenario II the decays of the heavy Higgs bosons to down type fermions are enhanced by tan 2 β, thus preferring decays to b-quarks and τ leptons, while decays to top quarks are suppressed by 1/ tan 2 β. In scenario I, the large values of the couplings λ − κ lead to decays of the heaviest scalar Higgs boson to the two lighter ones which is dominant for heavy Higgs boson masses below the tt decay threshold of about 400 GeV. For m H 3 > 400 GeV the decay into tt starts to dominate. These features have been summarized in Table 1. One additional feature of scenario II is the possibility to decay into gauginos, which is related to the value of µ ef f . This value is fixed in the CMSSM by EWSB and is usually large compared to M 1 , leading to the lightest neutralinos and charginos to be gaugino-like.
In the NMSSM µ ef f is related to the vev of the Higgs singlet and is a free parameter. As mentioned above, the fit within the 3D Higgs mass parameter space is not unique. To make sure that the fit is not locked in a local instead of a global minimum we also put a grid in the 6D parameter space and fitted for each bin in the λ − κ plane the remaining parameter tan β, A λ , A κ , A 0 and µ ef f . We checked that the range of resulting branching ratios is compatible with the results from the 3D Higgs mass scan, where all parameters were left free simultaneously. The transition between scenario I and II can be readily observed, if one plots the best fit value of tan β in the λ − κ plane, as shown in the top left panel of Fig. 1. The dark (blue) regions for λ ≥ 0.55 corresponds to scenario I, while the shaded (greenish) regions for λ ≤ 0.1 corresponds to scenario II. The right panel of Fig. 1 shows the χ 2 function of Eq. 8 without the χ 2 H 3 term, since m H 3 was allowed to vary in the plane. The region between the two greenish regions has a poorer χ 2 value, which originates from the fact, that neither the lightest nor the second lightest NMSSM Higgs boson has the right mass and right couplings in comparison with the observed Higgs boson. The white region within the λ − κ plane is not allowed, since for such large values of the parameters one reaches a Landau pole. For the benchmark points we choose a typical point in regions I and II (indicated by I and II in the left panel of Fig. 1). The corresponding parameter set and sparticle masses are given in Table 2. These benchmark points are each characterized by a specific branching ratio being dominant, as will be discussed later. The Higgs boson masses and LHC production cross sections for the four benchmark points have been summarized in Table 3.

LHC limits on Higgs boson masses
Apart from the observation of the SM-like Higgs boson at 125 GeV the LHC has not observed any other Higgs bosons, but placed limits on the heavy Higgs bosons. In SUSY the production cross section for the heavy Higgs boson is proportional to tan 2 β (see e.g. [28]), so the limits are a strong function of tan β [29,30]. Typically, heavy pseudo-scalar Higgs boson below 800 GeV are excluded for tan β ≥ 45, but no limits are obtained for tan β ≤ 4. Furthermore, the constraints from B-physics have to be taken into account. The b s → µµ decay modes (proportional to tan 6 β) requires rather heavy SUSY masses for large tan β or, alternatively, a small mass   splitting in the stop sector, see e.g. [31]. Not only b s → µµ but also b → sγ, restricts the allowed parameter space, so to be in agreement with the Bphysics constraints we chose tan β to be not larger than 30 for our benchmark points. The absolute lower limits of the heavier Higgs masses are given by the Higgs boson of 125 GeV. An additional lower limit on the heavier Higgs boson mass around 800 GeV exists in both scenarios. In scenario I this limit results from the relic density constraint if the correct relic density is required. Below this limit the relic density is too small, which is allowed if dark matter has contributions from particles different from the LSP. In scenario II (large Table 3: Masses of the Higgs bosons for BMP 1-4 and their corresponding Higgs production cross section at 14 TeV for the dominant gluon-gluon fusion process in scenario I and the vector boson fusion bbH for scenario II for the neutral Higgs bosons. The production cross section for the charged Higgs is given for the bottom-gluon fusion process. Note that for gluon fusion the A 2 production cross section is three times larger than the H 3 production cross section, although the masses are similar. tan β) the limit comes from the LHC, as discussed above.

Heavy Higgs branching ratios within the CMSSM
Before discussing the branching ratios in the NMSSM, we discuss the simpler case of the CMSSM, where only two free parameters (A 0 and tan β) enter the Higgs sector. The branching ratios of the heavy Higgs bosons were  down-type fermions. So the heaviest Higgs bosons are expected to decay into b-quarks and τ -leptons for masses below 1.5 TeV, which is close to the reach at the LHC [33]. Masses above 1.5 TeV require smaller values of tan β in order to increase m 2 2 . These smaller tan β values allow branchings into other channels. The widths of the bands originate mainly from the allowed variation of A 0 and tan β for a given mass.

Heavy Higgs branching ratios in the NMSSM
The large difference in the branching ratios of the heavy Higgs boson between the NMSSM and CMSSM is clear from a comparison of Figs. 2 and 3. The latter shows the branching ratios of the heavy scalar and pseudoscalar Higgs bosons as function of their masses in the NMSSM, again for the two CMSSM mass points discussed before.
In the CMSSM the scalar and pseudo-scalar heavy bosons have similar branching ratios, but in the NMSSM one has two scalar Higgs bosons with a mass below the heaviest one, so the heaviest one may decay into the two lighter ones (H 3 → H 1 H 2 ), if kinematically allowed. This is forbidden by parity conservation for the pseudo-scalar boson. Therefore, H 3 and A 2 have different branching ratios, as can be seen from Fig. 3. In the NMSSM the Higgs boson masses are largely independent of tan β, so for each mass considered both scenarios are possible, as shown in the different rows. The width of the bands corresponds mainly to the allowed variation of λ and κ. The variation of the lightest pseudo-scalar Higgs boson mass m A 1 between 25 and 500 GeV gives a smaller contribution to the width of the bands.
The bottom row with large tan β is similar to the branching ratios in the CMSSM (Fig. 2), i.e. large branching ratios into down-type fermions. They differ because of the chosen small values of µ ef f in the NMSSM, which leads to lighter neutralinos and charginos in comparison with the CMSSM, where µ is large due to EWSB. The lightest charginos and neutralinos in the NMSSM are in addition Higgsino and singlino-like in contrast to the bino and wino-like sparticles in the CMSSM. The threshold for the gauginos depends on m 1/2 , as can be seen from a comparison of the left and right panels in Fig.  3. Only the sum of the branching ratios into either charginos or neutralinos has been indicated.
For low values of tan β the decay modes into b-quarks and tau-leptons are typically absent and the decays into top quarks (when above threshold) or lighter Higgs bosons prevail, as can be seen from the top row in Fig. 3. For the pseudo-scalar Higgs mass the decay into two lighter scalar Higgs bosons  Figure 3: The branching ratios of a heavy Higgs boson in the NMSSM as function of its mass for scenario I (top,middle) and II (bottom). For scenario II the branching ratios for H 3 and A 2 are similar, so they have been plotted together in the last row. The main difference between the branching ratios of H 3 and A 2 in scenario I are the additional decays of A 2 into A 1 H 1/2 (orange band) and ZH 1 (solid black line) . These decays are not allowed for the scalar Higgs boson H 3 . The dominant branching ratios are shown as bands, where the width of the bands represents the allowed variation of the NMSSM parameters. To simplify the plot the smaller branching ratios have been shown as a line representing the average of the band. The decays into gauge boson pairs is negligible in both scenarios, while bb and τ τ are important in scenario II with large tan β. Decays into gaugino masses become possible as well, if they are light enough. Here they were chosen to correspond to CMSSM mass points not excluded by the LHC (m 0 =1000/2000, m 1/2 =1000/600 GeV left/right-hand side).
is forbidden, so the main decay modes are into top quarks and gauginos, as shown in the middle row of Fig. 3. If tan β is large (scenario II ) the dominant decay are into down-type fermions and gauginos, if kinematically allowed, as shown in the bottom row of Fig. 3. Within the bands of the possible branching ratios we propose two benchmark points for each scenario: one in which the heavy scalar Higgs decays mostly into H 1 H 2 (called BMP1) and one in which H 3 decays mostly into tt (called BMP2) for scenario I. In scenario II BMP3 corresponds to a dominant decay into a pair of b quarks. In BMP4 the decay into bb is reduced due to the significant decay into charginos and neutralinos. The heavy pseudo-scalar Higgs mass is almost degenerate in mass with the heavy scalar one, so they will be produced simultaneously, but with different branching ratios and cross sections. The masses and cross sections have been summarized before in Table 3. Numerical values of the branching ratios for the benchmark points are listed in Tables 4 and 5. The production cross section for the neutral Higgs bosons has been calculated for 14 TeV using SusHi [34][35][36][37][38][39][40][41][42]. The cross section for the charged Higgs boson at 14 TeV has been estimated using FeynHiggs [43][44][45][46][47]. Scenario I is dominated by the gluon fusion production cross section, while for scenario II with large tan β the bbH cross section dominates. Since the cross sections for charged Higgs production originate from the same diagrams in the MSSM and NMSSM, the values for the MSSM, as calculated with FeynHiggs, were taken. In the following we discuss some of the features of these benchmark points.

Benchmark point BMP1 with H 1 H 2 decay dominant in scenario I
The H 3 and A 2 bosons have practically the same mass (350 and 342 GeV, respectively), but they have quite different decays: H 3 decays for 68% into H 1 +H 2 , while A 2 decays for 49% into H 1 +Z and the remaining decay modes are largely gauginos but the production cross section of A 2 is 3 times larger compared to H 3 , see Table 3. The decay mode of the lightest pseudo-scalar Higgs boson A 1 , shown in Table 5, is not Z + H 1 , as in BMP2 (although the masses of the lighter Higgs bosons are identical), but the main decay mode is now into LSPs, so an invisible final state. This benchmark point is characterized by a large fraction of double Higgs production in the H 2 decay, while the A 2 decays into Z +H 1 or gauginos, either neutral or charged, which in turn have a rich spectrum of decay modes. The A 1 boson decays largely into invisible neutralinos, while the lightest Higgs boson H 1 decays largely into bb and tau-pairs. The charged Higgs boson decays largely into tb and W ± H 1 .

Benchmark point BMP2 with tt decay dominant in scenario I
The H 3 and A 2 bosons have similar masses (450 and 446 GeV, respectively). In both cases the tt decay is dominant, so the cross sections can be added. Note that H 3 can decay into H 1 + H 2 as well, while for A 2 the decay into H 1 + Z and LSPs yields the second largest branching ratio. A 1 decays largely into Z + H 1 , as shown in Table 5. So this benchmark point is characterized by a large fraction of tt final states, which can be searched for as a broad bump around 450 GeV in the tail of the tt invariant mass spectrum. Furthermore, events with two Z bosons and the H 1 Higgs boson of 100 GeV with practically SM decay modes can be searched for from the A 2 decay mentioned above. As can be seen from Table 4, the dominant decay mode for the charged Higgs is into tb and W ± H 1 .

Benchmark point BMP3 with bb decay dominant in scenario II
For this benchmark point the chosen masses of the heavy Higgs boson are heavier in comparison to BMP1 and BMP2. The branching ratios of H 3 and A 2 are shown in Table 4. The mass splitting for such heavy Higgs boson masses is negligible. In both cases the bb decay is dominant, so the cross sections can be added. But since this channel has a large background the smaller branching ratio into τ leptons with a smaller background may be the preferred search channel for the heavy Higgs boson. A 1 decays largely into charginos and neutralinos, as shown in Table 5. Although the mass of the charged Higgs boson is heavier compared to BMP1 and BMP2, the decay into tb and τ ν τ is dominant, because of the heavy charginos and neutralinos.
4.5. Benchmark point BMP4 with χ ± 1 χ ± 2 decay dominant in scenario II The last benchmark point has heavy Higgs boson masses around 1 TeV. The mass difference for H 3 and A 2 is negligible and their branching ratios are shown in Table 4. The bb decay is still significant, but the decay into charginos starts to dominate. Since the decay mode of the dominating branching ratio includes χ ± 2 one expects gauge bosons from its decay. Invisible decays are expected from A 1 , which decays largely into charginos and neutralinos, as shown in Table 5. For the charged Higgs boson the decay into charginos and missing transverse energy from the neutralinos starts to dominate, so the decay into tb decreases in comparison with the other benchmark points.

Conclusion
We surveyed the branching ratios of the Higgs bosons in the constrained minimal and next-to minimal supersymmetry scenarios. To limit the parameter space we restricted ourselves to the well-motivated common GUT scale masses for the SUSY partners, but the Higgs boson masses and their branching ratios are largely independent of the GUT scale constraints. The interest in the next-to-minimal scenario with an additional singlet stems among others from the increase at tree level of the SM-like Higgs boson, so the 125 GeV does not need large radiative corrections from stop loops. In addition, the µ-parameter in the NMSSM is naturally of the order of the electroweak scale, thus avoiding the µ-problem [11]. However, the Higgs sector has now 6 free parameters. This 6D parameter space makes it difficult to obtain insight in the possible range of masses and branching ratios. To solve this problem we considered instead the parameter space of the 6 Higgs masses, which reduces to a 3D mass space, if one takes into account that one Higgs mass has to be 125 GeV and the heavy Higgs bosons are practically mass-degenerate. By projecting the 6D parameter space of the NMSSM Higgs sector on the 3D parameter space of the masses we obtained the range of branching ratios of each Higgs boson mass in two typical scenarios, as shown in Table 1. Two benchmark points for each scenario have been presented, which can be used to search for signatures distinguishing the MSSM and NMSSM.
The recent diphoton excess by CMS [48] and ATLAS [49] may hint for a new particle with a mass around 750 GeV, which is in agreement with the allowed mass range for the heavy Higgs bosons. Due to the large mass many decay channels are possible, so the loop induced decay into photons leads to a branching ratio of the order of 10 −5 . The number of expected events is then well below one. However, about 10 have been observed in both experiments at a similar mass, which makes it difficult to dismiss the excess as a statistical fluctuation. The large discrepancy with the expected NMSSM cross section makes it also difficult to interpret the excess in the framework of SUSY, but many other explanations have been proposed, see e.g. [50][51][52][53][54]. Fortunately, future data will soon reveal if these are fluctuations or new physics.