REVIEW
A brief review of R-parity-violating couplings
High Energy Physics - Phenomenology · Submitted 18 Sep 1997 · 28 references
Pith's verdict: A genuinely useful, honestly sourced 1997 compilation of RPV limits, but the tables are one-coupling-at-a-time slices at m̃ = 100 GeV and the §3 summary should say so.
T0 · AI review
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Referee report
The paper
The paper claims
This review collects the tightest indirect upper bounds on all 45 R-parity-violating Yukawa couplings of supersymmetry, quoted at one sigma for a 100 GeV sfermion mass, with several entries recomputed from 1997 data.
The reading
What carries the argument
The machinery is the R-parity-violating superpotential itself, $W = 2^{-1}L_iL_jE^c_k + L_iQ_jD^c_k + U^c_iD^c_jD^c_k + L_iH_u$, and the fact that a single coupling of this kind can be rewritten, by a Fierz transformation or a loop calculation, into the same $(V-A)otimes(V-A)$ form as an ordinary weak amplitude. That is what makes the bounds possible: because the new amplitude and the Standard Model amplitude add coherently, each observable becomes a polynomial in one coupling, and the measured agreement with the Standard Model becomes an interval for that coupling. The paper's contribution is the systematic application of this translation to roughly a dozen observables and the assembly of the results into a single indexed table.
Extended reading notes
Core claim
The paper's claim is that its Tables 1 and 2 are the best indirect upper bounds available at the time on the 45 R-parity-violating Yukawa couplings — 27 of the $L$-violating $LQD^c$ type, 9 of the $LLE^c$ type, and 9 of the $B$-violating $U^cD^cD^c$ type — all at one $\sigma$ and for a common sfermion mass of 100 GeV, with the LEP and tau-decay entries recomputed from the 1997 data. The representative numbers are concrete: $|V_{ud}|$ universality and atomic parity violation pin $LQD^c$-type couplings with first-generation indices to the few-percent level, with $0.035$ for the atomic-parity-violation entry; neutrinoless double $\beta$ decay forces the purely first-generation coupling to $0.00035$; the electron-neutrino Majorana mass forces the third-generation $LLE^c$ coupling to $0.003$; double nucleon decay forces the baryon-violating coupling to $10^{-6}$ or below; and the LEP hadronic-to-leptonic ratio, with the top quark running in a triangle loop, bounds the third-generation couplings at $0.34$ to $0.50$. Product couplings fare far worse: proton stability requires $10^{-22}$ for the light-generation combination and $10^{-10}$ for any flavour combination, and kaon mixing requires $10^{-9}$. If the compilation is right, no R-parity-violating coupling outside these ranges survives the low-energy data then available.
Load-bearing premise
Every bound in the tables assumes that exactly one R-parity-violating coupling is nonzero at a time and that all sfermions sit at a common 100 GeV, so the numbers describe a one-dimensional slice of the allowed region rather than its full shape.
Editorial extensions
If this is right
- Any coupling whose product would mediate proton decay is forced below $10^{-22}$ for light generations and $10^{-10}$ for any flavour combination, so baryon-number violation in supersymmetry must be either absent or extraordinarily weak.
- The couplings with first-generation quark and lepton indices, which are exactly the ones invoked to explain the large-$Q^2$ HERA anomaly, are pushed to about $0.035$ or below by atomic parity violation, leaving little room for that explanation.
- Couplings carrying third-generation indices are the least constrained, at $0.34$ to $0.50$, because their leading loop diagrams require top quarks and so their effects are comparatively small.
- Because every entry is quoted at a common 100 GeV sfermion mass, a heavier superpartner sector weakens all the bounds, so the table should be read as the boundary of the allowed region for light supersymmetry rather than as a mass-independent statement.
Reading between the lines
- Every observable here is quadratic in the coupling, so a table of one-coupling-at-a-time limits does not by itself bound the case where two couplings are simultaneously comparable; a dedicated flat-direction analysis would be needed to close that gap, and the paper does not attempt one.
- The author marks the kaon-decay and $D^0$–$\bar D^0$ entries as basis-dependent, which means the two numbers $0.012$ and $0.20$ are not physical quantities but artefacts of assuming the CKM matrix equals one or the other of the two mixing rotations; a basis-independent formulation would be the statement worth carrying forward.
- The third-generation entries are set by LEP lineshape precision, so the same observables at a future $Z$ factory would tighten them roughly with the square root of the collected statistics — a straightforward experimental upgrade path the review does not spell out.
- Since the bounds scale with the assumed sfermion mass, a supersymmetric spectrum heavy enough to evade direct searches would relax the whole table, which means the strongest entries are conditional on light superpartners rather than on the R-parity-violating idea itself.
Original abstract
I review the upper limits on the R-parity-violating Yukawa couplings from indirect searches. Some limits have been updated using recent data.
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.
The abstract, sentence by sentence
I review the upper limits on the R-parity-violating Yukawa couplings from indirect searches. Some limits have been updated using recent data.
background contribution method result interpretation main claim
| # | sentence | role | the authors' own work | states the main conclusion | strength |
|---|---|---|---|---|---|
| s0 | I review the upper limits on the R-parity-violating Yukawa couplings from indirect searches. | contribution 0.98 | 0.37 | 0.19 | asserted 0.78 |
| s1 | Some limits have been updated using recent data. | contribution 0.82 | 0.42 | 0.10 | asserted 1.00 |
What was examined, and what was not
- arXiv listing abstract v2
- full text
- figures and tables
- references and citing sentences
- relations to other papers
- P abstract
- S sections
- T body sentences
- C citations
- R cross-paper relations
References
How the literature uses it
39 arXiv papers cite this in 48 sentences
Papers citing it · 21 sentences without a confident label
Uses its data or values 2 papers
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Then, the best upper limit on $$ comes from [ref] [equation] and its value is [equation] at 90% C.L..
Can Flavor Physics Hint at Distinctive Signals for R-parity Violation at the LHC? · R-Parity Violation: the Flavor Connection · 0.91
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This upper limit weakens to 0.002 and 0.1 for $m_q̃ =$ 200 and 600 GeV [ref] , respectively. $λ_3jk^''$ has been constrained from $R_l = Γ(Z →hadronic)/Γ(Z →l l̅)$ to $≲0.5$ for $m_q̃ = 100 GeV$ [ref] .
Electroweakino searches at the HL-LHC in the baryon number violating MSSM · Introduction · 0.94
Compares with it 1 paper
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The limits obtained are looser than those obtained from other experiments [ref] , so it is not possible to obtain upper bounds on RPV interactions from the $^199$Hg EDM experimental data.
R-parity violating supersymmetric contributions to the P, CP-odd electron-nucleon interaction at the one-loop level · Analysis of the P, CP-odd 4-quark interaction within R-parity violation at the one-loop level · 0.93
Cites it as background 23 papers
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Phenomenological constraints exist on each of these $λ'_ijk$ couplings and also on many of their products, taken pairwise [ref] .
Can Flavor Physics Hint at Distinctive Signals for R-parity Violation at the LHC? · R-Parity Violation: the Flavor Connection · 0.91
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Until now, many of the RPV interactions were constrained by high energy experiments, low energy precision tests, and cosmological phenomenology [ref] .
R-parity violating supersymmetric contributions to the neutron beta decay at the one-loop level · Introduction · 0.82
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In this work we focus on the $CP$ violation of the $R$-parity violating (RPV) sector [ref] .
R-parity violating two-loop level rainbowlike contribution to the fermion electric dipole moment · Introduction · 0.97
Discussion
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