REVIEW
Radiative contribution to neutrino masses and mixing in $\mu\nu$SSM
High Energy Physics - Phenomenology · Submitted 13 Feb 2010 · 116 references
Pith's verdict: The one-loop machinery is real and reusable; the headline 'accommodation' claim is an existence proof at a single benchmark point, and the abstract's comparative claim outruns it.
T0 · AI review
Why Pith says this
Highlight any text to comment on it.
Referee report
The paper
The paper claims
A supersymmetric neutrino model survives its own one-loop corrections, and normal mass ordering fits most easily.
The reading
What carries the argument
The load-bearing device is a perturbative block diagonalization of the $10��10$ neutralino-neutrino mass matrix using the expansion matrix $��xi = m_{3��7} M_{7��7}^{-1}$, whose entries are small because the Dirac-type entries $m_{3��7}$ are either left-sneutrino vacuum expectation values or Higgs vacuum expectation values times neutrino Yukawa couplings. This yields an effective light mass matrix $M^{��mathrm{seesaw}}_��nu = -m_{3��7} M_{7��7}^{-1} m_{3��7}^T$ with two competing seesaw structures: an ordinary seesaw scaling as $a_i^2/m_{��nu^c}$ with $m_{��nu^c} = 2��kappa v_c$, and a gaugino-mediated seesaw scaling as $c_i^2/M$ with $1/M = g_1^2/M_1 + g_2^2/M_2$, analogous to a Type-III seesaw. The paper's technical claim is that the one-loop corrections, when rotated back from the mass basis to the flavour basis, reproduce exactly this three-term $a_i a_j$, $c_i c_j$, $a_i c_j$ structure with new coefficients, so the loop analysis can be carried out on the $3��3$ matrix without redoing the full $10��10$ diagonalization.
Extended reading notes
Core claim
The authors compute all one-loop corrections to the $10��10$ neutralino-neutrino mass matrix of the $�mu�nu$SSM in 't Hooft-Feynman gauge and in the $��overline{��mathrm{DR}}$ scheme, including loops with neutral scalars and pseudoscalars, $Z^0$, $W^��$, charged scalars, and quarks and squarks. Rotating the corrections back to the flavour basis and re-applying the seesaw block structure, they argue that the one-loop corrected effective light neutrino mass matrix reduces to $��Delta m_f + M^{��mathrm{seesaw}}_{��nu}$, so that the loop effect can be captured by correcting the $3��3$ light mass matrix alone. That corrected matrix retains the tree-level three-term form $A_1 a_i a_j + A_2 c_i c_j + A_3(a_i c_j + a_j c_i)$, where $a_i = Y^{ii}_��nu v_2$ is the Dirac-type seesaw parameter and $c_i = v'_i$ is the left-sneutrino vacuum expectation value, but with coefficients that now depend on the model parameters and the Passarino-Veltman functions $B_0$ and $B_1$. Numerically, they scan the six parameters of the neutrino sector against the $3��sigma$ ranges of $��Delta m^2_{��mathrm{solar}}$, $|��Delta m^2_{��mathrm{atm}}|$, $��sin^2��theta_{12}$, $��sin^2��theta_{23}$, $��sin^2��theta_{13}$, and the non-oscillation bounds, and report that the data can be accommodated both at tree level and with one-loop corrections included. They further report that the normal hierarchical pattern is easier to fit than the inverted hierarchical or quasi-degenerate patterns once loops are included, with the inverted case in particular failing to find allowed regions for several of the scanned parameters.
Load-bearing premise
The conclusion that normal hierarchy is easier to fit than inverted or quasi-degenerate rests on holding the soft supersymmetry-breaking parameters and the right-sneutrino vacuum expectation values fixed at one benchmark set while scanning only the six neutrino-sector parameters, and the authors themselves note near the end of Section 4.3 that other choices could yield different orderings.
Editorial extensions
If this is right
- The $�mu�nu$SSM remains a viable joint solution to the $�mu$-problem and the neutrino mass problem once one-loop corrections are included, not merely at leading order.
- Because the loop-corrected light mass matrix keeps the same three-term form as the tree-level one, the correlations between neutrino mixing angles and ratios of lightest-neutralino decay branching ratios that were derived at tree level are expected to persist, with shifted coefficients.
- The allowed ranges of the model parameters $��kappa$ and $��lambda$ shift once loops are included: $��kappa$ moves to lower values and $��lambda$ shrinks toward higher values, so collider studies based on tree-level parameter ranges would need updating.
- Only a narrow window of $��tan��beta$, roughly 10 to 14, survives all neutrino constraints in the normal-hierarchy scan, which sharpens the model's prediction for the Higgs sector.
- The authors note that a singlino-dominated lightest supersymmetric particle remains compatible with the neutrino data, which would give the LHC a handle on the right-handed neutrino mass scale through displaced decays.
Reading between the lines
- If the three-term structure really is stable under loops, then the loop corrections act mainly as a renormalization of three effective coefficients rather than as a new source of flavour structure, which suggests the model's neutrino predictions are more rigid, and therefore more falsifiable, than its large parameter count would imply.
- The reported preference for normal hierarchy is a statement about one benchmark point in the soft supersymmetry-breaking sector; a broader scan would be the natural next step, and the paper's own closing remark in Section 4.3 concedes that other choices could reverse the ordering.
- The same machinery, applied in reverse, could be used to ask which regions of soft parameter space make the loop contribution dominate over the tree-level seesaw, which is a distinct question from whether the data can be fitted at all.
- Because the loop corrections are computed for the heavy neutralinos as well as the light neutrinos, the framework already contains the pieces needed for a dedicated radiative-correction analysis of the heavy neutralino masses, which the authors explicitly defer.
Original abstract
In an extension of the minimal supersymmetric standard model (popularly known as the $\mu\nu$SSM), three right handed neutrino superfields are introduced to solve the $\mu$-problem and to accommodate the non-vanishing neutrino masses and mixing. Neutrino masses at the tree level are generated through $R-$parity violation and seesaw mechanism. We have analyzed the full effect of one-loop contributions to the neutrino mass matrix. We show that the current three flavour global neutrino data can be accommodated in the $\mu\nu$SSM, for both the tree level and one-loop corrected analyses. We find that it is relatively easier to accommodate the normal hierarchical mass pattern compared to the inverted hierarchical or quasi-degenerate case, when one-loop corrections are included.
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
In an extension of the minimal supersymmetric standard model (popularly known as the $\mu\nu$SSM), three right handed neutrino superfields are introduced to solve the $\mu$-problem and to accommodate the non-vanishing neutrino masses and mixing. Neutrino masses at the tree level are generated through $R-$parity violation and seesaw mechanism. We have analyzed the full effect of one-loop contributions to the neutrino mass matrix. We show that the current three flavour global neutrino data can be accommodated in the $\mu\nu$SSM, for both the tree level and one-loop corrected analyses. We find that it is relatively easier to accommodate the normal hierarchical mass pattern compared to the inverted hierarchical or quasi-degenerate case, when one-loop corrections are included.
background contribution method result interpretation main claim
| # | sentence | role | the authors' own work | states the main conclusion | strength |
|---|---|---|---|---|---|
| s0 | In an extension of the minimal supersymmetric standard model (popularly known as the $\mu\nu$SSM), three right handed neutrino superfields are introduced to solve the $\mu$-problem and to accommodate the non-vanishing neutrino masses and mixing. | background 0.94 | 0.17 | 0.04 | asserted 1.00 |
| s1 | Neutrino masses at the tree level are generated through $R-$parity violation and seesaw mechanism. | background 0.88 | 0.13 | 0.04 | asserted 1.00 |
| s2 | We have analyzed the full effect of one-loop contributions to the neutrino mass matrix. | contribution 0.72 | 0.96 | 0.05 | asserted 0.98 |
| s3 | We show that the current three flavour global neutrino data can be accommodated in the $\mu\nu$SSM, for both the tree level and one-loop corrected analyses. | result 1.00 | 0.92 | 0.60 | asserted 0.98 |
| s4 | We find that it is relatively easier to accommodate the normal hierarchical mass pattern compared to the inverted hierarchical or quasi-degenerate case, when one-loop corrections are included. | result 0.98 | 0.96 | 0.29 | asserted 1.00 |
What was examined, and what was not
- arXiv listing abstract v3
- 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
Figures
Figures reproduced from arXiv:1002.2705 by the authors.
References
How the literature uses it
42 arXiv papers cite this in 69 sentences
Papers citing it · 51 sentences without a confident label
Uses its method or tool 1 paper
-
These corrections have been computed in [ref] .]), linked with modified subroutines for the model, based on the codes NMHdecay [ref] and Spheno [ref] .
The Higgs sector of the munuSSM and collider physics · Signals at colliders · 1.00
Cites it as support 2 papers
-
The smallness of the left sneutrino VEVs for a correct description of the neutrino sector, compatible with current data, has been shown in Refs. [ref] .
$U(1)'$ extensions of the $\mu \nu$SSM · The scalar potential · 0.99
-
In our numerical studies we fitted the experimentally well measured quantities [equation] We restricted ourselves in the neutrino sector to a tree-level analysis, because the one-loop corrections turn out to be moderate in size (in the normal hierarchy pattern) [ref] and can always be compensated by a small shift in the neutrino Yukawa couplings $Y^ν_ij$ without affecting the conclusions drawn in the scalar sector, in particular for the observables related to the SM-like Higgs boson.
Precise prediction for the Higgs-Boson Masses in the $\mu\nu$SSM with three right-handed neutrino superfields · Neutral fermion sector · 0.97
Cites it as background 14 papers
-
`$μ$ from $ν$' supersymmetric standard model ($$) [ref] , is a SUSY framework where the $μ$ problem is solved and the neutrino data can be reproduced [ref] .
Looking for the left sneutrino LSP with displaced-vertex searches · Introduction · 0.98
-
The $$ [ref] is a natural extension of the MSSM where the $μ$ problem is solved and, simultaneously, the neutrino data can be reproduced [ref] .
Sampling the $\mu\nu$SSM for displaced decays of the tau left sneutrino LSP at the LHC · The $$ · 0.91
-
The $$ [ref] is a natural extension of the MSSM where the $μ$ problem is solved and, simultaneously, neutrino data can be reproduced [ref] .
Explaining muon $g-2$ data in the $\mu\nu$SSM · Neutrino/sneutrino mass spectrum · 0.97
What it cites · 36 sentences without a confident label
Compares with 4 papers
-
Note that the one-loop diagrams in figure[ref], contributing to the neutrino mass matrix are very similar to those obtained in bilinear R-parity violating scenario [ref] .
Neutrino masses in the R-parity violating MSSM · Radiative corrections to neutrino mass terms · 0.99
-
Note that the one-loop diagrams in figure[ref], contributing to the neutrino mass matrix are very similar to those obtained in bilinear R-parity violating scenario [ref] .
Basis independent neutrino masses in the $R_p$ violating MSSM · Radiative corrections to neutrino mass terms · 0.99
-
Note that the one-loop diagrams in figure[ref], contributing to the neutrino mass matrix are very similar to those obtained in bilinear R-parity violating scenario [ref] .
Neutrino masses in R-parity violating supersymmetric models · Radiative corrections to neutrino mass terms · 0.99
Cites as background 19 papers
-
In $μν$SSM, the three generations of SM-neutrinos can acquire masses through a TeV-scale seesaw mechanism, with both neutralinos and heavy neutrinos participating in the process [ref] .
Neutrino masses and mixing, lightest neutralino decays and a solution to the $\mu$ problem in supersymmetry · Introduction · 0.88
-
The situation becomes different if one allows violation of the discrete symmetry known as $R$-parity ($R_p$) [ref] , defined as $R_p = (-1)^L + 3B + 2S$, where $L(B)$ is the lepton(baryon) number and $S$ is the spin, of a particle.
The R-Parity Violating Minimal Supergravity Model · Introduction · 0.91
-
Then one can have R-parity broken by bilinear terms [ref] of the type $ϵ_i L_i H_2$.
Neutrino masses in the R-parity violating MSSM · Introduction · 0.89
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.