A Minimal Spontaneously Broken Hidden Sector and its Impact on Higgs Boson Physics at the Large Hadron Collider

James D. Wells; Robert Schabinger

REVIEW

A Minimal Spontaneously Broken Hidden Sector and its Impact on Higgs Boson Physics at the Large Hadron Collider

Robert Schabinger, James D. Wells

High Energy Physics - Phenomenology · Submitted 21 Sep 2005 · 12 references

Pith's verdict: The s1 rate/width/invisible relations and the A-Higgs benchmark are correct and worth citing; the s2 sector has real algebra errors that should be fixed but do not touch the main claim.

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arXiv IDhep-ph/0509209 (version 2)

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CitationJames D. Wells, Robert Schabinger. "A Minimal Spontaneously Broken Hidden Sector and its Impact on Higgs Boson Physics at the Large Hadron Collider." arXiv:hep-ph/0509209 (2005). https://pith.science/paper/WKMNJCBW

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Editor's note

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Bottom line: the load-bearing part of this paper is right, and the A-Higgs benchmark is the reason to keep the preprint on your shelf. The s2 sector has genuine errors, but they sit off the main claim and do not change the conclusion the abstract advertises [abstract:s2]. The portal operator eta|H|^2|Phi|^2 is not new, and the paper says so and cites [1] and [5]. What is new is the packaging: Eqs. 20-22 give the rate ratio, the total width ratio, and B_inv for the lighter eigenstate in terms of m_s1, sin^2 omega, and r = Gamma_hid/Gamma_SM, and Eq. 23 names the r to infinity, sin^2 omega to zero, r sin^2 omega = A limit. I rederived 20-22 from the branching-fraction definitions and they are correct. The observation that the rate never exceeds the SM one is the quotable result, and a two-parameter benchmark with a clean invisible-branching prediction is a real contribution even if the algebra is elementary. The s2 sector is where it goes wrong. Eqs. 16-18 put c^2 Gamma_SM + s^2 Gamma_hid in the denominator, but s2 couples to the SM with sin omega, so it should be s^2 Gamma_SM + c^2 Gamma_hid + Gamma(s2 to s1 s1); the factors are swapped, and Eq. 16 as printed is garbled besides. Eq. 9's trilinear coupling does not come out of a direct expansion of Eq. 2. I get 3 lambda v c^2 s + 3 rho xi s^2 c - (eta/2)(xi c^3 + v s^3), so the printed eta^2 and the (3 lambda - eta), (3 rho - eta) coefficients look wrong. Eq. 10's 24 pi does not follow from L = mu s1^2 s2 either; the standard identical-particle two-body result gives 8 pi. None of this touches Eqs. 20-22, but the s2 to s1 s1 discussion should not be used as printed. The reader's worry that the A-Higgs limit may not be realizable is mild. Small eta and light hidden states give small sin^2 omega and large Gamma_hid independently, so the hierarchy is easy; the paper just does not exhibit a model. That is worth a sentence, not a referee objection. The SUSY section is a sketch: a 3x3 matrix and an eigenvalue bound, no numbers, and m^2_Z' gamma^2 ~ m^2_Z is asserted rather than shown. Fine as an analogue. Who it is for: anyone doing Higgs-portal or invisible-Higgs collider work. The A-Higgs benchmark is the citable object. Send it out.

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Major objections (2)

[Eqs. (16)-(18)] The denominators of the s2 branching fractions are incorrect as written. In Eq. (16) the denominator contains s_ω^2 Γ_SM^i(m_s2) + c_ω^2 Γ_SM^i(m_s2), which is simply Γ_SM^i(m_s2) and repeats the partial width already in the numerator; the correct denominator should be s_ω^2 Γ_SM(m_s2) + c_ω^2 Γ_hid(m_s2) + Γ(s2→s1s1). Eqs. (17) and (18) have the same problem in the opposite direction: they contain c_ω^2 Γ_SM + s_ω^2 Γ_hid where the correct assignment is s_ω^2 Γ_SM + c_ω^2 Γ_hid, since s2 couples to SM states with strength s_ω and to hidden states with strength c_ω. These errors affect the s2 branching fractions and the discussion of s2→s1s1 as a tell-tale signal, but they do not affect the central s1 results in Eqs. (20)-(23), which I have checked and find correct.
[Eq. (9)] I do not reproduce the η^2 term or the (3λ-η) and (3ρ-η) coefficients of Eq. (9) from a direct expansion of the potential in Eq. (2). Substituting h = c_ω s1 + s_ω s2 and φ = -s_ω s1 + c_ω s2 into the cubic terms of Eq. (2) with the +η|H|^2|Φ|^2 convention used for the mass matrix gives (3λ+η)v c_ω^2 s_ω + 3ρξ c_ω s_ω^2 + (η/2)(ξ c_ω^3 + v s_ω^3), up to the sign convention for η. Please re-derive Eq. (9) and state the convention explicitly. This affects Eq. (10) and the s2→s1s1 rate, but again not the central s1 results.

Minor objections (6)

[Eq. (5)] The sign of the (ρξ^2 - λv^2) term in the mixing-angle formula appears inconsistent with Eqs. (4), (6) and (7); the standard diagonalization of the matrix in Eq. (4) gives (λv^2 - ρξ^2) in that position. Since only s_ω^2 enters the s1 observables, this is harmless for the central results, but it should be corrected for internal consistency.
[Eq. (10)] Please state the normalization convention for µ (whether the Lagrangian term is µ s1^2 s2 or (µ/2) s1^2 s2), since the standard identical-particle phase space for a two-body decay gives a different prefactor from the one shown.
[Eq. (26)] Please clarify whether c2β denotes cos 2β or cos^2 β; the MSSM upper bound is m_Z^2 cos^2 2β, and the notation as printed is ambiguous.
[Eq. (23) and the A-Higgs model] The paper treats m_s1, sin^2ω and r as independent and takes r→∞ with sin^2ω→0 at fixed A. A brief demonstration that this hierarchy is realizable in a concrete hidden sector (for example, small η together with light hidden states or a large hidden quartic) would strengthen the claim that the A-Higgs model is a good benchmark rather than a formal limit.
[Introduction and Eq. (19)] The assumption that all hidden-sector decay products are invisible is stated in the introduction but is not repeated in the abstract or conclusions; since it is a scope limitation that determines the interpretation of B_inv, it would be worth restating where the benchmark is defined.
[Ref. [5]] Reference [5] is an Honors Thesis rather than a peer-reviewed publication; if any result in the present paper relies on it, that result should be reproduced here. The paper appears self-contained, so this is a minor point.

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The paper

The paper claims

If the Standard Model Higgs mixes with a Higgs boson of a hidden sector, the lighter of the two mass eigenstates is predicted to appear in every standard detection channel at a rate below the Standard Model one, and it may decay mostly into

The reading

The paper asks what the LHC would see if the Standard Model Higgs boson shares a renormalizable coupling with a Higgs boson of a hidden sector, meaning a sector with no Standard Model gauge charges but its own broken gauge symmetry. The single allowed portal operator, $|H|^2|Φ|^2$, forces the two neutral scalars to mix, so the physical states are combinations of the ordinary Higgs and the hidden one. The authors show that the lighter physical state is produced at every standard channel with a rate suppressed relative to the Standard Model, and that it can carry a large invisible branching fraction if the hidden sector offers light states for it to decay into. They reduce this to three inputs (the light mass, the mixing fraction, and the ratio of hidden to Standard Model widths) and then isolate a one-parameter benchmark, the A-Higgs model, for collider searches. The practical message is that a hidden sector does not hide by removing the Higgs from the spectrum; it hides by making the surviving Higgs quieter, possibly broader, and possibly invisible.

What carries the argument

The engine is the Higgs portal operator $η|H|^2|Φ|^2$, the only gauge-invariant renormalizable coupling between a Standard Model Higgs doublet and a hidden-sector Higgs that gets a vacuum expectation value. It generates an off-diagonal entry $η v ξ$ in the $2×2$ mass matrix of the real scalars, which is diagonalized by a mixing angle $ω$; the mass eigenstates $s_1$ and $s_2$ then share the Standard Model couplings in proportion to $c_ω^2$ and $s_ω^2$ while also inheriting decays into hidden states. Every observable in the paper follows from that single mixing angle plus the ratio $r = Γ_{hid}/Γ_{SM}$, which is why the whole phenomenology collapses onto the three-parameter description of Eq. 19 and, in the weak-mixing limit, onto the one-parameter A-Higgs benchmark.

Extended reading notes

Core claim

For the lighter mass eigenstate $s_1$, the ratio of any Higgs-mediated rate to the Standard Model rate is $R = (1- s_ω^2)^2 / [1 - (1-r) s_ω^2]$, where $s_ω^2$ is the mixing fraction and $r = Γ_{hid}/Γ_{SM}$. This ratio is never greater than one, so no state in the spectrum is produced as copiously as the Standard Model Higgs would be, and standard searches are strictly harder than the Standard Model case. The companion results are the total width, $Γ/Γ_{SM} = 1 - (1-r)s_ω^2$, which can be larger or smaller than the Standard Model width depending on $r$, and the invisible branching fraction, $B_{inv} = r s_ω^2/[1-(1-r)s_ω^2]$. The authors then take the limit $r → ∞$ with $s_ω^2 → 0$ at fixed $A = r s_ω^2$, in which the production cross-section returns to the Standard Model value while the standard-channel rate falls as $1/(1+A)$, the width grows as $1+A$, and the invisible fraction becomes $A/(1+A)$. This limit is named the A-Higgs model, has two free parameters (the light mass and $A$), and is offered as a benchmark for collider studies. A supersymmetric analogue follows when the hidden Higgs interacts with the MSSM Higgs doublets through a $U(1)_{hid}$ D-term, producing a $3×3$ mass matrix whose extra contribution can raise the lightest Higgs mass above the MSSM bound while leaving the same suppression and invisible-decay phenomenology.

Load-bearing premise

The paper treats the mixing fraction and the ratio of hidden to Standard Model widths as independent inputs, so the one-parameter A-Higgs benchmark requires sending the width ratio to infinity while the mixing goes to zero at fixed product; a concrete hidden sector ties both quantities to the same gauge and portal couplings, and the paper does not exhibit a model in which that correlated limit is actually realized.

Editorial extensions

If this is right

Any Higgs search channel at the LHC must be reinterpreted with a signal strength below one; a hidden-sector mixed Higgs is never easier to find than the Standard Model one in the standard modes.
The reconstructed mass peak can be narrower or broader than the Standard Model expectation depending on whether the hidden width ratio $r$ is below or above one, so peak width becomes a discriminating observable rather than a nuisance.
A light Higgs in the mass range where the Standard Model width is accidentally small can be dominated by invisible decays after only modest mixing, making invisible-final-state searches the primary discovery mode.
The A-Higgs model gives a two-parameter benchmark (light mass and $A$) with definite predictions: rate $1/(1+A)$, width $1+A$, invisible fraction $A/(1+A)$.
In the supersymmetric D-term version, the additional $m_{Z'}^2 γ^2$ contribution to the lightest Higgs mass can lift it above the MSSM tree-level bound, easing the tension with the experimental mass limit.

Reading between the lines

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

Because the suppression formula never exceeds unity, an observed excess over the Standard Model in any single standard channel would rule out pure $|H|^2|Φ|^2$ mixing as the explanation, which makes the prediction sharply falsifiable rather than merely adjustable.
A fit that floats signal strengths and total width simultaneously could separate this scenario from a plain overall coupling reduction, since the two scenarios differ in how width and rate move together as mixing grows.
If the lightest hidden-sector states are not stable but decay back into Standard Model particles inside the detector, the invisible branching fraction becomes a displaced or exotic visible signature, and the search strategy inverts.
The same portal logic applies to any hidden sector whose Higgs gets a vacuum expectation value, so the suppression pattern is a generic target for global Higgs coupling fits rather than a model-specific curiosity.

Original abstract

Little experimental data bears on the question of whether there is a spontaneously broken hidden sector that has no Standard Model quantum numbers. Here we discuss the prospects of finding evidence for such a hidden sector through renormalizable interactions of the Standard Model Higgs boson with a Higgs boson of the hidden sector. We find that the lightest Higgs boson in this scenario has smaller rates in standard detection channels, and it can have a sizeable invisible final state branching fraction. Details of the hidden sector determine whether the overall width of the lightest state is smaller or larger than the Standard Model width. We compute observable rates, total widths and invisible decay branching fractions within the general framework. We also introduce the ``A-Higgs Model'', which corresponds to the limit of a hidden sector Higgs boson weakly mixing with the Standard Model Higgs boson. This model has only one free parameter in addition to the mass of the light Higgs state and it illustrates most of the generic phenomenology issues, thereby enabling it to be a good benchmark theory for collider searches. We end by presenting an analogous supersymmetry model with similar phenomenology, which involves hidden sector Higgs bosons interacting with MSSM Higgs bosons through D-terms.

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, 6,310 input tokens, $0.0003 reported.

What the abstract itself states, as probabilities: claims first 0.04 · states limitation 0.54 · human participants 0.01 · controlled comparison 0.18 · randomized assignment 0.01 · states quantitative result 0.08 · compares with prior results 0.44 · 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.

Little experimental data bears on the question of whether there is a spontaneously broken hidden sector that has no Standard Model quantum numbers. Here we discuss the prospects of finding evidence for such a hidden sector through renormalizable interactions of the Standard Model Higgs boson with a Higgs boson of the hidden sector. We find that the lightest Higgs boson in this scenario has smaller rates in standard detection channels, and it can have a sizeable invisible final state branching fraction. Details of the hidden sector determine whether the overall width of the lightest state is smaller or larger than the Standard Model width. We compute observable rates, total widths and invisible decay branching fractions within the general framework. We also introduce the ``A-Higgs Model'', which corresponds to the limit of a hidden sector Higgs boson weakly mixing with the Standard Model Higgs boson. This model has only one free parameter in addition to the mass of the light Higgs state and it illustrates most of the generic phenomenology issues, thereby enabling it to be a good benchmark theory for collider searches. We end by presenting an analogous supersymmetry model with similar phenomenology, which involves hidden sector Higgs bosons interacting with MSSM Higgs bosons through D-terms.

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	Little experimental data bears on the question of whether there is a spontaneously broken hidden sector that has no Standard Model quantum numbers.	gap 0.83	0.05	0.02	asserted 0.96
s1	Here we discuss the prospects of finding evidence for such a hidden sector through renormalizable interactions of the Standard Model Higgs boson with a Higgs boson of the hidden sector.	contribution 0.98	0.51	0.06	hedged possibility 0.44
s2	We find that the lightest Higgs boson in this scenario has smaller rates in standard detection channels, and it can have a sizeable invisible final state branching fraction.	result 1.00	0.95	0.62	asserted 0.91
s3	Details of the hidden sector determine whether the overall width of the lightest state is smaller or larger than the Standard Model width.	result 0.95	0.59	0.09	asserted 0.61
s4	We compute observable rates, total widths and invisible decay branching fractions within the general framework.	contribution 0.86	0.96	0.08	asserted 1.00
s5	We also introduce the ``A-Higgs Model'', which corresponds to the limit of a hidden sector Higgs boson weakly mixing with the Standard Model Higgs boson.	contribution 0.70	0.88	0.05	asserted 1.00
s6	This model has only one free parameter in addition to the mass of the light Higgs state and it illustrates most of the generic phenomenology issues, thereby enabling it to be a good benchmark theory for collider searches.	contribution 0.51	0.79	0.10	asserted 0.93
s7	We end by presenting an analogous supersymmetry model with similar phenomenology, which involves hidden sector Higgs bosons interacting with MSSM Higgs bosons through D-terms.	contribution 0.97	0.82	0.05	asserted 1.00

What kind of paper the classifier reports this is: theoretical result 0.99 · evidence from simulation or computation 0.61.

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.** The rate of Higgs boson observables σiBj relative to that of the SM for various values of r = Γhid/Γ SM = 0, 0.1, 1, 10, 100 (from top to bottom). Note, the rate never exceeds that of the SM, thus making detection of hidden sector mixed Higgs bosons more challenging than detection of the SM Higgs boson. In Figs. 1, 2 and 3 we plot for various values of rs1 the three observables σiBj/(σiBj )SM, Γ/Γ SM and Binv. In

**Figure 2.** The total width compared to that of the SM total width fo

**Figure 3.** The invisible branching fraction of the lightest Higgs boson

Figures reproduced from arXiv:hep-ph/0509209 by the authors.

References

Works cited (12)

[1]

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[5]

R. Schabinger, “The Phenomenological Possibilities Introduced b y an Exotic Scalar,” Honors Thesis, University of Michigan, Ann Arbor, April 2005

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J. McDonald, Phys. Rev. D 50, 3637 (1994). C. P. Burgess, M. Pospelov and T. ter Veldhuis, Nucl. Phys. B 619, 709 (2001) [hep-ph/0011335]. H. Davoudiasl, R. Kitano, T. Li and H. Murayama, Phys. Lett. B 609, 117 (2005) [hep-ph/0405097]

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See, for example, M. E. Peskin and J. D. Wells, Phys. Rev. D 64, 093003 (2001) [hep-ph/0101342]

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J. D. Wells, “Extra dimensions and the universal suppression of H iggs boson observables at high energy colliders,” SUSY 2002 (DESY, Hamburg), hep-ph/020 5328

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J. F. Gunion, Phys. Rev. Lett. 72, 199 (1994) [hep-ph/9309216]. D. Choudhury and D. P. Roy, Phys. Lett. B 322, 368 (1994) [hep-ph/9312347]. S. G. Frederiksen, N. Johnson, G. L. Kane and J. Reid, Phys. Rev. D 50 (1994) 4244. O. J. P. Eboli and D. Zeppenfeld, Phys. Lett. B 495, 147 (2000) [hep-ph/0009158]

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A. Datta and A. Raychaudhuri, Phys. Rev. D 57, 2940 (1998) [hep-ph/9708444]. B. P. Kersevan, M. Malawski and E. Richter-Was, Eur. Phys. J. C 29, 541 (2003) [hep-ph/0207014]. R. M. Godbole, M. Guchait, K. Mazumdar, S. Mor etti and D. P. Roy, Phys. Lett. B 571, 184 (2003) [hep-ph/0304137]. M. Battaglia, D. Dominici, J. F. Gu- nion and J. D. Wells, hep-ph/04...

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S. P. Martin and J. D. Wells, Phys. Rev. D 60, 035006 (1999) [hep-ph/9903259]. B. A. Dobrescu, G. Landsberg and K. T. Matchev, Phys. Rev. D 63, 075003 (2001) [hep-ph/0005308]

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[11]

For some recent discussions of collider probes of the NMSSM see U. Ellwanger, J. F. Gunion and C. Hugonie, hep-ph/0503203. G. Moortgat-Pick, S. Hesselbach, F. Franke and H. Fraas, hep-ph/0502036. D. J. Miller, R. Nevzoro v and P. M. Zerwas, Nucl. Phys. B 681, 3 (2004) [hep-ph/0304049]. U. Ellwanger, J. F. Gunion, C. Hugonie and S. Moretti, hep-ph/0401228

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[12]

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Mirror World at the Large Hadron Collider
hep-ph 2005-09 conditional novelty 6.0 of 10

Mirror-world Higgs mixing suppresses LHC production by a factor of two, gives distinctive invisible and cascade decays, and can raise the top-quark naturalness cutoff by up to a factor of six.
Leveraging the ALICE/L3 cavern for long-lived exotics
hep-ph 2018-10 conditional novelty 5.5 of 10

A detector built in the existing ALICE/L3 cavern could, for roughly 100 inverse femtobarns of delivered luminosity, reach long-lived particle couplings comparable to or better than MATHUSLA and SHiP for Higgs, B-meson...
Study of ZZ and ZH production in the bb$\tau\tau$ final state and search for high-mass spin-0 and spin-1 resonances in proton-proton collisions at $\sqrt{s}$ = 13 TeV
hep-ex 2026-07 unverdicted novelty 5.0 of 10

CMS sets 95% CL upper limits on σ(X)B(X→ZZ) (300 pb–24 fb) and σ(Z')B(Z'→ZH) (0.4 pb–12 fb) for resonances up to 6 TeV in the bbττ channel with no SM deviation observed.
Constraining Multiple Kinetically Mixed Dark Photons
hep-ph 2026-06 unverdicted novelty 5.0 of 10

Develops a statistical framework to constrain multiple kinetically mixed dark photons using standard experimental probes and distributions for mixing parameters.
Search for decays of the Higgs boson into pair-produced pseudoscalar particles decaying into $\tau^+\tau^-\tau^+\tau^-$ using $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
hep-ex 2026-03 accept novelty 5.0 of 10

No significant excess is observed; 95% CL upper limits on B(H→aa→4τ) range from 0.06 to 0.23 for ma between 15 and 60 GeV.
GeV-scale thermal dark matter from dark photons: tightly constrained, yet allowed
hep-ph 2025-07 conditional novelty 5.0 of 10

In a dark-photon-mediated Dirac fermionic DM model, only narrow resonant regions with small dark-sector coupling allow the candidate to saturate the full relic density while evading current direct and indirect detecti...
Expression of Interest for the CODEX-b Detector
hep-ex 2019-11 conditional novelty 5.0 of 10

CODEX-b would be a shielded, background-free detector 25 m from the LHCb interaction point, and the paper argues a simulated background of 0.22 multitrack events per 300 fb^-1 supports competitive reach across roughly...
Combination of searches for Higgs boson pair production in proton-proton collisions at $\sqrt{s} =$ 13 TeV
hep-ex 2018-11 conditional novelty 5.0 of 10

No sign of Higgs boson pair production appears in 35.9 fb^-1 of 13 TeV CMS data; the combined 95% CL upper limit is 22.2 (expected 12.8) times the standard-model cross section.
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.
Looking through the Pseudo-Scalar Portal into Dark Matter: Novel Mono-Higgs and Mono-$Z$ Signatures at LHC
hep-ph 2015-09 conditional novelty 5.0 of 10

Resonant production of a heavy pseudoscalar that decays to a Higgs or Z plus a dark mediator yields mono-Higgs and mono-Z signatures with a sharp missing-energy cutoff, projected to be observable at the 14 TeV LHC.
Search for a high-mass Higgs boson decaying to a $W$ boson pair in $pp$ collisions at $\sqrt{s} = 8$ TeV with the ATLAS detector
hep-ex 2015-09 accept novelty 5.0 of 10

No heavy Higgs boson appears in 8 TeV ATLAS data; for a narrow-width scalar at 1500 GeV the production cross section times WW branching ratio is bounded below 22 fb (gluon fusion) and 6.6 fb (vector-boson fusion) at 95% CL.
Electroweak Baryogenesis from Exotic Electroweak Symmetry Breaking
hep-ph 2015-04 conditional novelty 5.0 of 10

A two-stage electroweak phase transition, with baryogenesis occurring in an exotic scalar transition before the standard Higgs vacuum forms, is realizable in an inert two-Higgs-doublet model provided a singlet raises ...
Benchmarks for Higgs Effective Theory: Extended Higgs Sectors
hep-ph 2015-02 conditional novelty 5.0 of 10

Explicit dimension-six matching coefficients are derived for singlet, two-Higgs-doublet, and dilaton extensions of the Higgs sector, and used to estimate where the effective field theory breaks down.
Exploring Resonant di-Higgs production in the Higgs Singlet Model
hep-ph 2014-10 conditional novelty 5.0 of 10

Requiring the electroweak vacuum to be the global minimum of a singlet-extended Higgs potential bounds resonant di-Higgs production at the 14 TeV LHC to at most about 18 times the Standard Model rate, for a 270 GeV he...
Search for Scalar Diphoton Resonances in the Mass Range $65-600$ GeV with the ATLAS Detector in $pp$ Collision Data at $\sqrt{s}$ = 8 $TeV$
hep-ex 2014-07 accept novelty 5.0 of 10

No significant diphoton resonance appears between 65 and 600 GeV in 20.3 fb^-1 of ATLAS 8 TeV data, and 95% CL upper limits on fiducial cross-section times BR(X to gamma gamma) fall from 90 fb at 65 GeV to 1 fb at 600 GeV.
Probing the Standard Model with Higgs signal rates from the Tevatron, the LHC and a future ILC
hep-ph 2014-03 accept novelty 5.0 of 10

Combined Tevatron and LHC Higgs signal rates are consistent with Standard Model couplings, additional undetectable Higgs decay is bounded below 40% at 95% confidence under a gauge-coupling assumption, and a future ILC...
Exotic Decays of the 125 GeV Higgs Boson
hep-ph 2013-12 accept novelty 5.0 of 10

The paper maps about twenty exotic Higgs decay topologies onto the models that produce them and derives new Run 1 limits on several by reinterpreting existing ATLAS and CMS analyses.
How well do we need to measure the Higgs boson mass and self-coupling?
hep-ph 2013-05 conditional novelty 5.0 of 10

The Higgs mass needs no better than the LHC's 150 MeV precision, while the Higgs self-coupling must reach roughly 20 percent accuracy before beyond-Standard-Model physics could show up in it.
Higgs Boson self-coupling measurements using ratios of cross sections
hep-ph 2013-01 conditional novelty 5.0 of 10

The double-to-single Higgs production cross section ratio cancels most QCD uncertainty and, under stated experimental assumptions, can constrain the Higgs trilinear coupling to be positive at 600 fb^-1 and to about +3...
ScannerS: Constraining the phase diagram of a complex scalar singlet at the LHC
hep-ph 2013-01 conditional novelty 5.0 of 10

A new public scanning code maps the surviving phases of complex singlet extensions of the Standard Model and identifies regions where a future LHC scalar measurement would exclude the dark-matter phase.
First Glimpses at Higgs' face
hep-ph 2012-07 conditional novelty 5.0 of 10

Global fits to the first 8 TeV LHC Higgs data put the Standard Model about 2 sigma from the best-fit scalar couplings, with an invisible branching ratio below roughly 0.4 at 95% confidence.
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 ...
Strong electroweak phase transitions without collider traces
hep-ph 2009-04 conditional novelty 5.0 of 10

A heavy, unmixed singlet scalar can produce a first-order electroweak phase transition strong enough for baryogenesis and BBO gravitational waves while remaining invisible at colliders.
Some Cosmological Implications of Hidden Sectors
hep-ph 2008-09 conditional novelty 5.0 of 10

Hidden-sector scalars coupled to the Higgs generically drive a strongly first-order electroweak phase transition, with detectable gravitational waves only under percent-level tuning and dark matter viable only in regi...
Thermal Relics in Hidden Sectors
hep-ph 2008-08 conditional novelty 5.0 of 10

Hidden-sector dark matter whose mass scales with the square of its gauge coupling gets the observed relic density for masses from keV to TeV, and large hidden sectors survive BBN if they are modestly colder than the v...
Higgs boson decays to four fermions through an abelian hidden sector
hep-ph 2008-01 conditional novelty 5.0 of 10

For a hidden abelian sector with gauge kinetic mixing and Higgs mixing, the decay h to Z'Z' to four leptons yields a clean LHC signal whose rate sits far above background at the benchmark points studied.
Heavy Dark Matter Through the Higgs Portal
hep-ph 2008-01 conditional novelty 5.0 of 10

Including non-perturbative Sommerfeld enhancement of the annihilation rate lets a Higgs-portal singlet fermion saturate the measured dark matter density at masses up to about 25 TeV, well above the usual thermal-relic...
Possible Effects of a Hidden Valley on Supersymmetric Phenomenology
hep-ph 2006-07 conditional novelty 5.0 of 10

If the LSP sits in a confining hidden valley sector, every SUSY event yields two decays into soft, poorly isolated v-hadrons, weakening missing-energy searches at the Tevatron and LHC and motivating displaced-vertex a...
Linking the Gauge Hierarchy with Neutrino Masses and Dark Matter via Two-step Cosmological Selection
hep-ph 2026-05 unverdicted novelty 4.0 of 10

A multiverse cosmological selection mechanism in an SM extension with scalar singlet and RH neutrinos under B-L dynamically fixes the EW scale while addressing neutrino masses, leptogenesis, and dark matter.
Search for Higgs boson exotic decays into Lorentz-boosted light bosons in the four-$\tau$ final state at $\sqrt{s}=13$ TeV with the ATLAS detector
hep-ex 2025-03 unverdicted novelty 4.0 of 10

Search for H->aa->4tau (4<m_a<15 GeV) with boosted di-tau reconstruction finds no excess and sets 95% CL upper limits of 0.03-0.10 on (sigma_H/sigma_SM)*BR(H->aa->4tau).
Search for resonances decaying into photon pairs in 139 fb$^{-1}$ of $pp$ collisions at $\sqrt{s} =$ 13 TeV with the ATLAS detector
hep-ex 2021-02 accept novelty 4.0 of 10

No resonance appears in the 139 fb^-1 ATLAS diphoton spectrum; 95% CL limits exclude RS1 gravitons below 4.5 TeV for k/MPl = 0.1 and bound fiducial diphoton cross-sections down to 0.03 fb at 2.8 TeV.
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...
Search for new phenomena in high-mass diphoton final states using 37 fb$^{-1}$ of proton-proton collisions collected at $\sqrt{s}=13$ TeV with the ATLAS detector
hep-ex 2017-07 accept novelty 4.0 of 10

No significant diphoton excess appears in 36.7 fb^-1 of 13 TeV ATLAS data; RS1 Kaluza-Klein gravitons below 4.1 TeV and ADD cutoff scales below 5.7 to 8.6 TeV are excluded.
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
hep-ex 2017-07 accept novelty 4.0 of 10

No Higgs-pair excess appears in 35.9 fb^-1 of 13 TeV CMS data in the bbττ channel; the observed 95% CL upper limit is about 30 times the standard model rate and the expected limit about 25.
Searches for Higgs boson pair production in the $hh\to bb\tau\tau, \gamma\gamma WW*, \gamma\gamma bb, bbbb$ channels with the ATLAS detector
hep-ex 2015-09 accept novelty 4.0 of 10

Combining four ATLAS di-Higgs search channels in 8 TeV data yields a 95% CL upper limit of 0.69 pb on nonresonant hh production (70 times the Standard Model) and resonant limits from 2.1 pb at 260 GeV to 0.011 pb at 1000 GeV.
Constraints on new phenomena via Higgs boson couplings and invisible decays with the ATLAS detector
hep-ex 2015-09 accept novelty 4.0 of 10

Combining Run 1 ATLAS Higgs measurements, the invisible Higgs branching ratio is bounded below 0.23 at 95% confidence and the hMSSM pseudoscalar is excluded below 370 GeV.

See all 71 Pith citations

How the literature uses it

128 arXiv papers cite this in 154 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 · 71 sentences without a confident label

Uses its method or tool 1 paper

The hard process $pp→Z→A'h_D$, $h_D→A'A'$ was generated in MadGraph using the HAHM model [ref] with $ϵ=10^-2$, $κ=10^-10$, $m_h_D=50$ GeV, and 6 GeV $≤m_A'≤$ 24 GeV.

Limits on an Exotic Higgs Decay From a Recast ATLAS Four-Lepton Analysis · The ATLAS MC Study · 0.95

Compares with it 1 paper

This result is analogous to the one obtained in the classically scale-invariant theory with a Higgs portal [ref] , where the EW symmetry breaking scale is induced radiatively by the Coleman-Weinberg mechanism, and the smallness of the Higgs VEV is explained naturally through the added Higgs portal.

Linking the Gauge Hierarchy with Neutrino Masses and Dark Matter via Two-step Cosmological Selection · Cosmological Selection Mechanism · 0.95

Cites it as background 75 papers

We work in the context of the theory motivated and developed in Refs. [ref] .

Dark matter and Higgs boson collider implications of fermions in an abelian-gauged hidden sector · Introduction · 0.83
[ref] and its recent revival in form of hidden sector theories [ref] .

Strong electroweak phase transitions without collider traces · The Model · 0.90
This dark photon can subsequently decay to charged Standard Model fermions through mixing with the photon [ref] .

Searching for Long-lived Particles: A Compact Detector for Exotics at LHCb · Introduction · 0.95

Discussion

Disagree with the review, or know something it missed? Leave a comment, highlight any passage above to comment on it, or challenge this review formally.

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R. Schabinger, “The Phenomenological Possibilities Introduced b y an Exotic Scalar,” Honors Thesis, University of Michigan, Ann Arbor, April 2005

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J. F. Gunion, Phys. Rev. Lett. 72, 199 (1994) [hep-ph/9309216]. D. Choudhury and D. P. Roy, Phys. Lett. B 322, 368 (1994) [hep-ph/9312347]. S. G. Frederiksen, N. Johnson, G. L. Kane and J. Reid, Phys. Rev. D 50 (1994) 4244. O. J. P. Eboli and D. Zeppenfeld, Phys. Lett. B 495, 147 (2000) [hep-ph/0009158]

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A. Datta and A. Raychaudhuri, Phys. Rev. D 57, 2940 (1998) [hep-ph/9708444]. B. P. Kersevan, M. Malawski and E. Richter-Was, Eur. Phys. J. C 29, 541 (2003) [hep-ph/0207014]. R. M. Godbole, M. Guchait, K. Mazumdar, S. Mor etti and D. P. Roy, Phys. Lett. B 571, 184 (2003) [hep-ph/0304137]. M. Battaglia, D. Dominici, J. F. Gu- nion and J. D. Wells, hep-ph/04...

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S. P. Martin and J. D. Wells, Phys. Rev. D 60, 035006 (1999) [hep-ph/9903259]. B. A. Dobrescu, G. Landsberg and K. T. Matchev, Phys. Rev. D 63, 075003 (2001) [hep-ph/0005308]

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For some recent discussions of collider probes of the NMSSM see U. Ellwanger, J. F. Gunion and C. Hugonie, hep-ph/0503203. G. Moortgat-Pick, S. Hesselbach, F. Franke and H. Fraas, hep-ph/0502036. D. J. Miller, R. Nevzoro v and P. M. Zerwas, Nucl. Phys. B 681, 3 (2004) [hep-ph/0304049]. U. Ellwanger, J. F. Gunion, C. Hugonie and S. Moretti, hep-ph/0401228

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See, for example, G. W. Anderson, D. J. Castano and A. Riotto , Phys. Rev. D 55, 2950 (1997) [hep-ph/9609463]. G. L. Kane, T. T. Wang, B. D. Nelson and L. T. Wang, Phys. Rev. D 71, 035006 (2005) [hep-ph/0407001]. 11

View on Pith Pith review arXiv 1997