Escaping the Large Fine Tuning and Little Hierarchy Problems in the Next to Minimal Supersymmetric Model and h-> aa Decays

John F. Gunion; Radovan Dermisek

REVIEW

Escaping the Large Fine Tuning and Little Hierarchy Problems in the Next to Minimal Supersymmetric Model and h-> aa Decays

Radovan Dermisek, John F. Gunion

High Energy Physics - Phenomenology · Submitted 11 Feb 2005 · 28 references

Pith's verdict: The paper that made light singlet pseudoscalars a mainstream escape from MSSM fine tuning; the logic holds, but the LEP h→aa limits it leans on are imported without quantification.

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arXiv IDhep-ph/0502105 (version 2)

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CitationJohn F. Gunion, Radovan Dermisek. "Escaping the Large Fine Tuning and Little Hierarchy Problems in the Next to Minimal Supersymmetric Model and h-> aa Decays." arXiv:hep-ph/0502105 (2005). https://pith.science/paper/NYCMX3GK

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Editor's note

read the letter

Worth your time. This is the short letter that turned 'light singlet pseudoscalar plus h1 → a1a1' into a standard escape from MSSM fine tuning, and the chain of reasoning survives a careful read. The mechanism is explicit: small A_kappa gives a light a1, h1 → a1a1 dominates, mh1 below 114 GeV survives LEP, and F drops to about 5.5 at geometric-mean stop masses of 250–400 GeV. The contrast with Bastero-Gil et al. [21], who raised mh by pushing lambda to its perturbativity limit, is stated cleanly and the two routes are genuinely different. The fine-tuning procedure is standard and described well enough to reimplement: fix mZ-scale parameters, run to the GUT scale, shift each parameter, run back, reminimize, recompute mZ. NMHDECAY and HDECAY are public. The paper also does the field a service by naming the channels the scenario predicts — four b, four tau, two b two tau — instead of leaving the LHC program to guess. That list is why this got cited so much. On the soft spots, the stress-test concern lands partially. The LEP h → aa limits come from NMHDECAY's implementation of the published DELPHI [15] and OPAL [16] analyses, and the paper never shows the effective limit as a function of ma1 or says which subchannels are included. That is a real documentation gap and a referee should ask for the ma1-dependent limit plot, especially near 2mb and 2m_tau. But the collapse scenario — every F < 20 point excluded — requires the published experimental limits to be wrong, which is not this paper's burden, and the authors are upfront that all low-F points sit below 114 GeV. Two smaller things. The scan is described only as random, with no point count or acceptance rate, so the abstract's 'always' is stronger than the body's 'nearly always.' And the low-F points need a light gluino: F ~ 40 at M3 = 700 GeV, so F ~ 5.5 means M3 ~ 300 GeV. That is the part of the result that has aged worst. Large tan beta fine tuning is not studied, and they say so. For anyone working on naturalness or on non-standard Higgs decays at the LHC, this is required reading and a fair referee assignment.

Referee report

Significance

If the result holds, the fine-tuning and little-hierarchy problems are properties of the MSSM Higgs sector rather than of weak-scale supersymmetry as such, which is a substantive claim for the field. The paper has real methodological strengths: the fine-tuning measure is defined explicitly and applied uniformly to the MSSM and NMSSM, so the internal comparison is apples-to-apples; the scan uses public codes (NMHDECAY, HDECAY) and cites the DELPHI and OPAL h → aa analyses rather than asserting limits from nowhere; and the conclusion is falsifiable and operationally specific, naming the a1a1 → 4τ window 2mτ < ma1 < 2mb and the WW → h1 → a1a1 → bbτ+τ− channel as targets. The prediction that the SM-like Higgs is h1 with near-SM couplings but dominant exotic decays is a concrete, testable statement that the experimental community can act on.

Major objections (4)

[Figs. 2–3 and the sentence 'We see that F as small as F ∼ 5.5 can be achieved for √(m~t1 m~t2) ∼ 250 ÷ 400 GeV'] The headline number depends entirely on the survival of mh1 < 114 GeV points, which in turn depends on NMHDECAY's encoding of the DELPHI [15] Zh → Zaa → Zbbbb and OPAL [16] Zh → Zaa → 4τ limits. The text asserts only that 'LEP is less sensitive to this channel as compared to the traditional h1 → bb decays' and never quantifies the gap. Please state explicitly which channels NMHDECAY includes (Zbbbb, Z4τ, and whether mixed Zbbττ or missing-energy channels enter), and show the accepted points in the (ma1, BR(h1 → a1a1)) plane with the published limit contours overlaid, especially near ma1 = 2mb and ma1 = 2mτ where the a1 decay topology changes. Note also that the two suppressions are correlated: the singlet admixture that suppresses a1 → bb also controls the h1a1a1 coupling and hence BR(h1 → a1a1), so the net Zbbbb rate is not obvious from the text and should be shown rather than asserted.
[Abstract, second sentence, versus the paragraph 'For very large tan β (e.g. tan β ∼ 50)...'] The abstract makes a claim for large tanβ ('For small tan(beta) [large tan(beta)], the relevant scenarios are such that there is always (often) a SM-like Higgs boson that decays to two lighter pseudoscalar Higgses'), but the body states 'We have not yet studied fine-tuning at very large tan β in either model,' and no large-tanβ scan is presented anywhere in the letter. Either present at least a preliminary large-tanβ scan supporting the 'often' claim, or restrict the abstract to the tanβ = 3 and tanβ = 10 cases actually studied.
[Abstract, first sentence, and the scan description preceding Fig. 2] The abstract claim of 'evading all experimental constraints' is broader than what the scan enforces. NMHDECAY checks the Higgs sector and sparticle mass limits (the text mentions m~t1 ≥ 100 GeV), but the scan does not appear to impose b → sγ, (g − 2)μ, Bs → μμ, dark-matter relic density, or direct SUSY search limits. With stop masses of 250–400 GeV and the low |µeff| values admitted by the scan, several of these are not automatic. Please either extend the checks or narrow the abstract and the corresponding sentence in the text to the constraints actually applied.
[Text following Fig. 3, and footnote [27]] The statement that 'even for mh1 ≥ 114 GeV, the lowest F value of F ∼ 24 is far below that attainable for mh ≥ 114 GeV in the MSSM' is compared against the F ∼ 185 of Fig. 1, but footnote [27] states that F ≳ 60 can be obtained in the MSSM with substantially larger |At|. The improvement is therefore a factor of roughly 2.5, not 8, and the text should say so. Please also add the large-|At| MSSM points to Fig. 1 so that the reader can see the true MSSM benchmark against which the NMSSM number is being measured.

Minor objections (7)

[Caption of Fig. 2] The caption reads 'Points marked by + (×) escape LEP exclusion primarily due to dominance of h1 → a1a1 decays (due to mh1 > 114 GeV),' which contradicts the body text stating that × points have mh1 > 114 GeV and escape regardless of the dominant decay mode. The parenthetical should be rewritten to match the text.
[Scan description preceding Fig. 2] The number of scanned points and the acceptance rate after NMHDECAY are not given, so the reader cannot judge the statistical weight of statements such as 'all points with F < 20 have mh1 < 114 GeV.' Please report the sample size and rephrase such statements as 'all scanned points' unless a denser or systematic scan supports the stronger reading.
[Definition of F, Eq. (5) and the accompanying text] The text notes that some papers use d log mZ^2 / d log a rather than d log mZ / d log a. Since the quoted F values will be compared with the MSSM literature, please state the conversion factor explicitly (a factor of two) so that the comparison with [23] and similar works is transparent.
[Scan description preceding Fig. 2] The top mass is fixed at mpolet = 175 GeV. Since mh1 near the 114 GeV boundary controls which points survive, please state the sensitivity of the LEP-survival boundary and of the quoted minimum F to a shift of a few GeV in mt.
[Paragraph beginning 'A small value for Aκ(mZ)...'] The claim that the a1 has a large singlet component and is therefore not excluded by Υ decays is asserted without a quantitative estimate. Please give the relevant Υ → γa1 branching-ratio bound or a reference establishing it for the singlet admixtures in question.
[Scan description preceding Fig. 2] The bound λ ≲ 0.7 from perturbativity up to the GUT scale is quoted without a stated criterion or reference. Please specify whether this is a one-loop or two-loop condition and cite the analysis.
[Fig. 4 and the tanβ = 3 discussion] The text notes that no points with mh1 > 114 GeV were found at tanβ = 3. Please state whether this is a structural feature of the low-tanβ regime or an artifact of the scan range and sample size, since it bears on how general the h1 → a1a1 escape route is.

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The paper

The paper claims

The next-to-minimal supersymmetric model can reach fine-tuning as small as a few while keeping stops light, because its lightest Higgs boson hides in decays to a pair of pseudoscalars.

The reading

The Minimal Supersymmetric Standard Model has a well-known problem: to push its lightest Higgs boson above the LEP mass bound, the stop masses must be around a TeV, which costs a fine-tuning measure $F$ of order 185 or more. This paper argues that the Next-to-Minimal Supersymmetric Model (NMSSM), which adds one singlet superfield, does not have to pay that price. Scanning the six-parameter NMSSM Higgs sector and applying all theoretical and experimental constraints, the authors find viable points with $F$ as small as about 5.5 at geometric-mean stop masses of only 250 to 400 GeV. The reason these points survive is not that their lightest CP-even Higgs $h_1$ is heavy — it is usually below 114 GeV — but that it decays dominantly into two light pseudoscalars $a_1$, a channel to which the LEP searches were far less sensitive than the standard $h_1 to b bar b$ search. If this holds, the fine-tuning and little-hierarchy problems are properties of the MSSM's particular Higgs sector rather than of weak-scale supersymmetry as such, and the Higgs discovery channels everyone has been planning are the wrong ones.

What carries the argument

The load-bearing object is the NMSSM minimization condition recast as a quadratic in $m_Z^2$, $m_Z^4 + 2B m_Z^2 + C = 0$, whose solution $m_Z^2 = -B pm sqrt{B^2 - C}$ permits cancellation between the two terms when $C ll B^2$. That cancellation, not any large radiative correction, is what suppresses the logarithmic derivatives $F = max_a |d log m_Z / d log a|$. The second mechanism is the light pseudoscalar: a small trilinear $A_kappa$ makes $m_{a_1}$ small, so the SM-like $h_1$ decays mainly to $a_1 a_1$, and the LEP limits on $Zh to Zaa to Zbbbb$ and $Z tau^+ tau^- tau^+ tau^-$ are weaker than the standard $h to b bar b$ limit. The paper notes that the small-$A_kappa$, small-$m_{a_1}$ regime is motivated by an approximate $U(1)_R$ symmetry.

Extended reading notes

Core claim

The central claim is that the NMSSM admits parameter choices that satisfy every available experimental constraint while keeping fine-tuning small and stops light. Two ingredients do the work. First, one combination of the NMSSM minimization conditions gives a quadratic in $m_Z^2$ of the form $m_Z^4 + 2B m_Z^2 + C = 0$, with $B$ and $C$ built from soft masses, $lambda$, $kappa$ and $tan beta$; when $C ll B^2$ the derivatives of $m_Z^2$ with respect to GUT-scale parameters cancel between the two branches of the solution, and $F$ collapses. Second, a small $A_kappa$ (of order a few GeV) keeps the pseudoscalar $a_1$ light enough that $h_1 to a_1 a_1$ dominates, which is what lets the low-$F$ points with $m_{h_1} < 114$ GeV escape LEP exclusion. The authors report $F sim 5.5$ at $sqrt{m_{tilde t_1} m_{tilde t_2}} sim 250$–$400$ GeV for $tan beta = 10$, and state that all points with $F < 20$ have $m_{h_1} < 114$ GeV and $mathrm{BR}(h_1 to a_1 a_1) > 0.70$. At $tan beta = 3$ they find $F sim 15$ at $sqrt{m_{tilde t_1} m_{tilde t_2}} sim 300$ GeV with no points above 114 GeV, all surviving through $h_1 to a_1 a_1$. Even restricting to $m_{h_1} geq 114$ GeV, the smallest $F$ found is about 24, still far below the MSSM's 185.

Load-bearing premise

The whole low-fine-tuning result rests on the claim that the LEP limits on a Higgs boson decaying to two pseudoscalars are genuinely much weaker than the standard $h to b bar b$ limit, since every point with $F < 20$ has $m_{h_1} < 114$ GeV and would be excluded if that were not so.

Editorial extensions

If this is right

If the NMSSM cancellation mechanism is real, the fine-tuning and little-hierarchy problems are not generic to weak-scale supersymmetry; they are specific to the MSSM Higgs sector, and models with an extended Higgs sector can be natural with stops in the 250 to 400 GeV range.
A SM-like Higgs boson below 114 GeV can still be allowed, provided its dominant decay is into a pair of light pseudoscalars; the standard LEP mass bound is then not a bound on the Higgs mass but a bound on the $h to b bar b$ branching ratio.
Tevatron and LHC Higgs searches built around $h to b bar b$, $h to W W$, $h to tau tau$ and $h to gamma gamma$ will lose sensitivity in exactly the parameter region that is least fine-tuned, so the standard no-lose theorems do not carry over from the MSSM to the NMSSM.
The $a_1 a_1 to tau^+ tau^- tau^+ tau^-$ final state, dominant for $2 m_tau < m_{a_1} < 2 m_b$, becomes a priority search channel; the authors argue it is not excluded by Upsilon decays because the $a_1$ has a large singlet component.
The authors state that existing work suggesting only a marginal LHC signal in $W W to h_1 to a_1 a_1 to b bar b tau^+ tau^-$ for $m_{a_1} > 2 m_b$ should be either refuted or improved upon.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

The result reframes the naturalness debate: instead of asking how heavy superpartners must be, one should ask how many Higgs states there are and which decay channels the experiments actually cover. A model can be natural and still have escaped detection for a decade simply by routing its Higgs through an unsearched final state.
A sharper version of this argument would quantify how much weaker the LEP $h to aa$ limits are than the $h to b bar b$ limit as a function of $m_{a_1}$, particularly near the $2 m_b$ and $2 m_tau$ thresholds; the paper does not do this, and the size of the allowed region depends on it.
If $h_1 to a_1 a_1$ really dominates in the low-$F$ region, then the inclusive $e^+ e^- to Zh$ recoil-mass measurement is the only model-independent handle, which makes a future lepton collider the decisive instrument for this scenario rather than a complement to the LHC.
The same logic should apply to any supersymmetric model with extra singlet states and light pseudoscalars; a systematic scan over such models would test whether the NMSSM is special or the first example of a broader class.

Original abstract

We demonstrate that the NMSSM can have small fine tuning and modest light stop mass while still evading all experimental constraints. For small tan(beta) [large tan(beta)], the relevant scenarios are such that there is always (often) a SM-like Higgs boson that decays to two lighter -- possibly much lighter -- pseudoscalar Higgses.

The compiled record

The paper's own sentences, arranged, kept beside the review and separate from it. Each label is drawn from a closed vocabulary; the number beside it is the probability the classifier gave that label. Numbers in the tables are the authors', checked by code. No sentence in this record was written by a model.

Compiled by classifier-1.13-20260917 via OpenRouter, question bank abstract-p1-20260923, 2026-09-23: 1 request, 2,317 input tokens, $0.0001 reported.

What the abstract itself states, as probabilities: claims first 0.03 · states limitation 0.22 · human participants 0.02 · controlled comparison 0.03 · randomized assignment 0.01 · states quantitative result 0.08 · compares with prior results 0.09 · mentions code or data availability 0.02.

The abstract, sentence by sentence

arXiv listing abstract v2. Results and the main claim are underlined; show every role.

We demonstrate that the NMSSM can have small fine tuning and modest light stop mass while still evading all experimental constraints. For small tan(beta) [large tan(beta)], the relevant scenarios are such that there is always (often) a SM-like Higgs boson that decays to two lighter -- possibly much lighter -- pseudoscalar Higgses.

background contribution method result interpretation main claim

What the classifier reports for each sentence. The number is the probability it gave the label.
#	sentence	role	the authors' own work	states the main conclusion	strength
s0	We demonstrate that the NMSSM can have small fine tuning and modest light stop mass while still evading all experimental constraints.	result 0.77	0.91	0.76	asserted 1.00
s1	For small tan(beta) [large tan(beta)], the relevant scenarios are such that there is always (often) a SM-like Higgs boson that decays to two lighter -- possibly much lighter -- pseudoscalar Higgses.	result 0.98	0.68	0.22	asserted 0.57

What kind of paper the classifier reports this is: theoretical result 0.96 · evidence from simulation or computation 0.75.

What was examined, and what was not

sources read

arXiv listing abstract v2

not examined

full text
figures and tables
references and citing sentences
relations to other papers

levels run

P abstract

not run

S sections
T body sentences
C citations
R cross-paper relations

Every quoted sentence on this record is the authors'. Every label is from Pith's closed vocabulary, with the probability shown beside it. Every number in the measurements table is the authors', checked by code. Record as JSON

Figures

**Figure 1.** This is the essence of the current fine-tuning problem for the CP-conserving MSSM. Also, to achieve mh > 114 GeV, √met1 met2 >∼ 1 TeV is required, an indicator of the little hierarchy problem. We now contrast this to the NMSSM situation. One combination of the three potential minimization equations yields the usual MSSM-like expression for m2 Z in FIG. 1: Left: the fine-tuning measure F in the MSSM is plotted vs. pmet1 met2 , without regard to LEP constraints on mh. The + points have mh < 114 GeV and are excluded by LEP limits. The × points have mh > 114 GeV and are experimen

**Figure 2.** FIG. 2: For the NMSSM, we plot the fine-tuning measure

**Figure 3.** FIG. 3: For the NMSSM, we plot the fine-tuning measure

Figures reproduced from arXiv:hep-ph/0502105 by the authors.

References

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Higgs Sector in Extensions of the MSSM
hep-ph 2006-03 conditional novelty 6.0 of 10

A systematic comparison shows the NMSSM, nMSSM, and UMSSM allow lighter or heavier neutral Higgs bosons than the MSSM, and the secluded U(1)' model reduces to the nMSSM when its extra singlets decouple.
Search for Higgs boson decays to beyond-the-Standard-Model light bosons in four-lepton events with the ATLAS detector at $\sqrt{s}=13$ TeV
hep-ex 2018-02 accept novelty 5.0 of 10

No significant excess is observed in H to ZX or XX to four leptons at 13 TeV, and 95% CL upper limits are set near 0.1% for H to Z Zd, 0.01% for H to Zd Zd, and 1% for H to aa, depending on the new boson mass.
Search for light bosons in decays of the 125 GeV Higgs boson in proton-proton collisions at sqrt(s) = 8 TeV
hep-ex 2017-01 accept novelty 5.0 of 10

No sign of Higgs decays to pairs of light bosons in 19.7 fb^-1 of 8 TeV CMS data; 95% CL upper limits on the exotic branching fraction reach 17% (4 tau), 16% (2 mu 2 b), and 4% (2 mu 2 tau) in favorable 2HDM+S scenarios.
Search for a non-standard-model Higgs boson decaying to a pair of new light bosons in four-muon final states
hep-ex 2012-10 accept novelty 5.0 of 10

Zero events were observed in the four-muon signal region against 1.0 plus or minus 0.5 expected background, giving a 95% CL upper limit of 0.86 plus or minus 0.06 fb on cross section times branching fraction times acceptance.
Les Houches 2011: Physics at TeV Colliders New Physics Working Group Report
hep-ph 2012-03 conditional novelty 5.0 of 10

The report proposes a Dark Matter Les Houches Agreement file format, extends the Flavour and SUSY accords to dipole moments and see-saw models, and reports new tool modules for automated RGE derivation and model validation.
Exploring the Higgs Portal with 10/fb at the LHC
hep-ph 2011-12 conditional novelty 5.0 of 10

New scalars coupled through the Higgs portal can plausibly explain a doubled diphoton rate at 124-126 GeV or suppress gluon fusion enough to hide a heavy Higgs, and the surviving parameter space overlaps regions that ...
RECAST: Extending the Impact of Existing Analyses
hep-ex 2010-10 conditional novelty 5.0 of 10

Recomputing only the signal efficiency through an archived analysis chain yields valid new exclusion limits for alternative models, and a three-part web framework is proposed to systematize such requests.
Discovering New Light States at Neutrino Experiments
hep-ph 2010-08 conditional novelty 5.0 of 10

Neutrino beam-dump experiments can probe long-lived pseudoscalars and dark photons beyond earlier beam-dump reach, with LSND setting the strongest pseudoscalar limits below the muon threshold.
Constraints on a very light CP-odd Higgs of the NMSSM and other axion-like particles
hep-ph 2010-05 conditional novelty 5.0 of 10

The sub-muon-threshold window for a light CP-odd Higgs is closed unless its fermion coupling is below roughly 10^-4 times the Standard Model Higgs coupling, pushing its mass above about 210 MeV.
Search for neutral Higgs bosons decaying into four taus at LEP2
hep-ex 2010-03 accept novelty 5.0 of 10

No excess of four-tau events in ALEPH LEP2 data excludes, at 95% confidence, h -> aa -> 4tau signal strengths above the Standard Model Higgsstrahlung rate for mh < 107 GeV and 4 < ma < 10 GeV.
Constraining the Axion Portal with B -> K l+ l-
hep-ph 2009-11 accept novelty 5.0 of 10

Existing B to K lepton-pair data bound the axion decay constant of DFSZ-type axion-portal models to be above roughly a few TeV for small tan beta, constraining the model's dark matter parameter space.
A Little Solution to the Little Hierarchy Problem: A Vector-like Generation
hep-ph 2009-10 conditional novelty 5.0 of 10

A vector-like fourth generation with order-one Yukawa couplings can raise the MSSM Higgs mass above 114 GeV with soft masses near 300 GeV, cutting the little-hierarchy fine-tuning by roughly a factor of ten.
Search for Higgs boson decays into a pair of light bosons in the $bb\mu\mu$ final state in $pp$ collision at $\sqrt{s} = $13 TeV with the ATLAS detector
hep-ex 2018-07 conditional novelty 4.0 of 10

No significant excess appears in the H to aa to bbμμ channel, and 95% CL upper limits on the branching ratio are set between 1.2×10^-4 and 8.4×10^-4 for a-boson masses of 20 to 60 GeV.
Search for the Higgs boson produced in association with a vector boson and decaying into two spin-zero particles in the $H \rightarrow aa \rightarrow 4b$ channel in $pp$ collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector
hep-ex 2018-06 accept novelty 4.0 of 10

No excess of H to aa to 4b events is observed in 36.1 fb^-1 of 13 TeV ATLAS data, and 95% CL upper limits on the WH and ZH production rates times the H to aa to 4b branching ratio range from 3.0 pb at ma = 20 GeV to 1...
Status of the Higgs Singlet Extension of the Standard Model after LHC Run 1
hep-ph 2015-01 conditional novelty 4.0 of 10

Combining unitarity, vacuum stability, the one-loop W mass, LEP and LHC Higgs searches, and LHC signal rates leaves only a narrow window for a second real singlet Higgs between 1 GeV and 1 TeV.
Simplified Models for LHC New Physics Searches
hep-ph 2011-05 accept novelty 4.0 of 10

A community workshop produced a standardized catalog of simplified models for LHC new-physics searches, intended to make experimental limits reusable across many theories.
Dark Discrete Gauge Symmetries
hep-ph 2010-06 accept novelty 4.0 of 10

A broken dark U(1) gauge symmetry can leave a Z_N remnant that stabilizes dark matter, and for composite N it can stabilize several species simultaneously, giving distinctive nuclear recoil spectra and Higgs decay patterns.
LHC Phenomenology of an Extended Standard Model with a Real Scalar Singlet
hep-ph 2007-06 conditional novelty 4.0 of 10

A single real scalar singlet added to the Standard Model either dilutes LHC Higgs signals through mixing or hides the Higgs behind invisible decays, and precision electroweak data plus the relic density pin down which.
Theory and phenomenology of two-Higgs-doublet models
hep-ph 2011-05 accept novelty 3.0 of 10

The review organizes the theory and phenomenology of two-Higgs-doublet models, including flavour-safe variants, charged-scalar searches, vacuum stability, and minimal spontaneous CP-violation constructions.
Central Exclusive Particle Production at High Energy Hadron Colliders
hep-ph 2010-06 accept novelty 3.0 of 10

The review argues that central exclusive production is now a quantitatively testable channel: perturbative QCD calculations of the Durham type are consistent with CDF dijet, chi_c and photon-pair data, which makes exc...
Physics searches at the LHC
hep-ph 2009-12 accept novelty 3.0 of 10

A structured review pairing each major TeV-scale model of new physics with the LHC signatures it would produce, and showing how an observed signature can be traced back to a class of underlying models.
The Next-to-Minimal Supersymmetric extension of the Standard Model reviewed
hep-ph 2009-06 accept novelty 2.0 of 10

A comprehensive review of the NMSSM covering its superpotential, Higgs and neutralino sectors, theoretical and cosmological constraints, and a Groebner-basis method for locating the global minimum of the Higgs potential.

How the literature uses it

88 arXiv papers cite this in 118 sentences

Each citing sentence is taken from the citing paper's LaTeX source and typed by Pith's classifier. A label appears at probability 0.8 or more (0.95 for support), a contest at 0.7 or more; the quoted words are the citing authors'. How each label was checked · JSON

Papers citing it · 83 sentences without a confident label

Uses its data or values 1 paper

From the result of the LEP we know that the lower bound of the SM Higgs mass is $114.4$GeV [ref] .[If the R-parity is broken, the lightest Higgs mass can be lower than the LEP bound [ref] .]

Constraints of the $B_{\mu}/\mu$ solution due to the hidden sector renormalization · The Basic Scheme · 0.94

Compares with it 2 papers

The important difference is that the scenario discussed in Refs. [ref] is the usual decoupled scenario as far as the two Higgs doublet part of the Higgs spectrum is concerned (the CP-odd Higgs, the heavy CP-even Higgs and the charged Higgs are heavy and approximately degenerate) and the light CP-odd Higgs is supplied by the additional singlet.

Many Light Higgs Bosons in the NMSSM · Introduction · 0.97
A light neutralino also appears in this region of parameters making a clear distinction with the scenario studied previously in Refs. [ref] .

Light Dark Matter and the Electroweak Phase Transition in the NMSSM · The near Peccei-Quinn symmetry limit of the NMSSM · 0.96

Cites it as support 6 papers

As already stressed and as described below in more detail, we are particularly led to the above interpretation of LEP data since fine-tuning within the NMSSM is absent for model parameters that yield precisely this kind of scenario [ref] .

The NMSSM Solution to the Fine-Tuning Problem, Precision Electroweak Constraints and the Largest LEP Higgs Event Excess · Introduction · 0.99
Such a Higgs can be light, as predicted from SUSY, gives better agreement with precision electroweak data, and can even explain the largest excess of Higgs like events at LEP [ref] .

Hidden Higgs Scenarios: new constraints and prospects at the LHC · Motivation for non-standard Higgs decays · 0.98
Such a Higgs can be light, as predicted from SUSY, gives better agreement with precision electroweak data, and can even explain the largest excess of Higgs like events at LEP [ref] .

Light charged Higgs in the NMSSM · Motivation for the light charged Higgs scenario · 0.99

Cites it as background 24 papers

The most studied scenario (and the first one to point out the improved naturalness with a hidden Higgs) is in the context of the NMSSM [ref] .

Hidden Higgs Decaying to Lepton Jets · Introduction · 0.84
Other studies have also looked at purely Higgsino-singlino spectra [ref] , direct stop [ref] or gluino [ref] production and the possibility that the singlino may be light [ref] .

Naughty or Nice? The Role of the `N' in the Natural NMSSM for the LHC · Introduction · 0.97
Extensions of the MSSM by a singlet chiral superfield are motivated in order to explain the size of the $μ$ term [ref] , to raise the mass of the lightest CP even Higgs boson above the LEP II bound [ref] , to reduce electroweak fine-tuning [ref] , or to catalyze electroweak baryogenesis [ref] .

Extended MSSM Neutralinos as the Source of the PAMELA Positron Excess · Introduction · 0.83

Discussion

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