Questions tagged [mssm]
MSSM stands for the Minimal Supersymmetric Standard Model.
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Degrees of freedom in the early universe with MSSM?
As nicely summarized on P4 in On effective degrees of freedom in the early universe here; at high temperatures where all the particles of the Standard Model are present, we have 28 bosonic and 90 ...
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Are there enough parameters in standard model to falsify SUSY?
I know that the search for Higgs would be quite pointless if there was no estimation of its mass.
Namely the perturbative violation of unitatity, gave us an upper bound on its mass.Unitarity ...
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Questions about "A Quadrillion Standard Models from F-theory"
This afternoon, I tried to read through this paper claiming to "present $\mathcal{O}(10^{15})$ string compactifications with the exact chiral spectrum of the Standard Model of particle physics&...
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How does SUSY differ from just having standard model (SM) particles in new Lorentz Group representations?
Under the standard model (SM), it is the irreducible representations of the Lorentz group which allows us to classify particles according to their spin. We can then further label particles using the ...
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MSSM interactions
I have seen many pictures of fermion-boson interactions. But none of them are related to gravitons and MSSM particles.
Do gravitons interact with photons, gluons and other particles?
What about the 4 ...
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F-theory questions on MSSM vs. SM compatibility and on de Sitter vacua
Having read https://arxiv.org/abs/2112.03947, https://arxiv.org/abs/1903.00009 and https://arxiv.org/abs/1903.00009, I noted the use of MSSM (Minimal Supersymmetric Standard Model) as if equivalent to ...
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In context of MSSM, what is stop mixing?
In context of MSSM, what is stop mixing and stop mixing parameter?
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Have we ruled out the Minimal Supersymmetric Standard Model (MSSM)?
This question is inspired by a Physics Stackexchange question posted 8 years ago (The future of supersymmetry). The question that I have is very similar to the question in the above link, except that ...
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Meaning of "Minimal" in "Minimal Supersymmetric Standard Model"
From what I am aware of, the LHC has ruled out the Minimal Supersymmetric Standard Model (MSSM), or at least highly constrain it. "Minimal" means that supersymmetry is introduced into the ...
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Has the ${\cal N}=1$ Minimal SUSY standard model been ruled out by the nature? [duplicate]
Question: Has the ${\cal N}=1$ Minimal SUSY standard model (MSSM) been ruled out by the nature? What are the natural constraints that ruled out such ${\cal N}=1$ MSSM?
In particular, the ${\cal N}=1$...
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Why are explicit mass terms allowed for sfermions like higgsinos and gauginos in the MSSM Lagranian if explicit fermionic mass terms are prohibited?
In Martin's SUSY Primer, he claims:
For the higgsinos and gauginos, [the ability to have a mass term]
follows from the fact that they are fermions in a real representation
of the gauge group.
As I ...
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Electron as Superpartner of Higgs!
Can we identify Higgs as a superpartner of the electron in a massless case? We know, superpartners have the same mass so of course, we can't and one argument we can make there are two Higgs doublets ...
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Why is there no $H_1H_1\bar{e}^c$ term in the most general renormalisable superpotential?
I am these notes by Jeff Asaf Dror on Supersymmetry. In the section on the MSSM, it is stated that the most general renormalisable superpotential is given by
$$W=y_1QH_2\bar{u}^c+y_2QH_1\bar{d}^c+...
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How did Supersymmetry (incorrectly) predict the mass of the Higgs Boson?
In an article by CERN states
The minimal version of supersymmetry predicts that the Higgs boson mass should be less than 120-130 GeV
How was this conclusion reached? I could not find any answers on ...
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Why are the particles identified that way in the MSSM?
In the MSSM the known fermions are the h=1/2 part of a h=0, h=1/2 multiplet. The gauge bosons are the h=1 part of a h=1, h=1/2 multiplet.
Why is it this way round? Why are the fermions not part ...
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What is the difference between supersymmetry and MSSM?
What is the difference between supersymmetry and MSSM? Please explain in a simple language i am just a beginner of supersymmetry
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What is a holomorphic combination of standard model fields?
I am looking at exotic Higgs decay models like SM + Fermion and MSSM. In SM + Fermion the new fermion might have a three body decay and in MSSM for R-parity violating neutralino decays involve ...
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SUSY particles as Dark Matter
In SUSY, why is only the neutralino considered the best candidate for dark matter, why not the other SUSY particles?
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MSSM (Minimal Supersymmetric Standard Model)
I have to write the action in superfield for SM with the Higgs, but I have problems with the mass term.
This is what I have (I don't know if it is right):
$$S_{1}=Tr\left(W^{\alpha}W_{\alpha}\right)\...
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How does the MSSM pseudo-scalar heavy Higgs undergo the decay process A -> Z h?
As A is a pseudo-scalar, Z an axial vector and h being a scalar, it looks like the spins are not balanced on both sides. Is it related to the longitudinal mode of Z boson?
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How do we know that A is a pseudoscalar (CP-odd) Higgs?
Starting from a model with two complex Higgs doublets (as e.g. in the MSSM) we arrive at 5 physical Higgs bosons (instead of 1 as in the Standard Model), 2 of which are charged and 3 are neutral. One ...
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B and L violation by non-perturbative electroweak effects
I was reading about the definition of R-parity on this paper http://arxiv.org/abs/hep-ph/9709356 (pg. 53 54). The author says that postulating B and L numbers conservation in the MSSM is sub-optimal ...
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How can we use Majorana spinors for charged fermions in MSSM?
According to "Supersymmetry in Particle Physics" by Ian Aitchison (see e.g. p62 of arXiv), in the Minimal Supersymmetric Standard Model (MSSM) we can use Majorana language to build supermultiplets:
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Soft SUSY breaking fermion mass terms in MSSM for matter fields
In the Minimal Supersymmetric Standard Model, the chiral fermion fields (the Higgsinos) don't have any soft SUSY breaking mass terms and soft SUSY breaking trilinear interactions while their scalar ...
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Matching bosonic and fermionic degrees of freedom in Wess-Zumino Lagrangian
In Wess-Zumino model, supersymmetric Lagrangian in addition to the ordinary complex scalar field $\phi$ contains auxiliary field $F$ (also complex scalar) to match the degrees of freedom of the Weyl (...
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Why we do we consider explicit SUSY breaking in the MSSM and not an spontaneous breaking of SUSY?
Reading about the minimal supersymmetric standard model (MSSM) I have found that an explicit breaking of supersymmetry is considered, given by the term
$$\cal{L}_{soft}$$
where soft supersymmetry ...
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Viability of a Fayet Iliopoulos term in the MSSM
Why is a Fayet-Iliopoulos term $-kD$ irrelevant or subdominant in the in the MSSM (Minimal Susy Standard Model)?
According to Martin (A Supersymmetry Primer, p.70) it's because squarks and sleptons ...
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Understanding the $\mu$ problem
I am going through the motivation to introduce singlet extensions of the MSSM (like for instance the NMSSM), and of course such a motivation is naturalness. Here, one argues that the $\mu$ parameter ...
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How do gauginos and scalars gain masses after gauge-mediated symmetry breaking?
In the minimal-GMSB model, the messenger fields transform under the MSSM gauge group and connect a so-called hidden sector to the visible sector. These meesenger fields (left-handed chiral ...
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Running chargino/neutralino masses in MSSM
Consider the plot below, showing the running of different masses due to renormalization for a certain point of the (c)MSSM. I am able to exactly reproduce the plot, including the running of M1, M2, M3....
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Have we found a Higgsino?
In supersymmetry, for each particle (boson/fermion), there is a symmetric particle which is a fermion/boson.
The MSSM predicts five Higgs bosons: two neutral scalar ones (H and h), a pseudo-scalar (A) ...
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Why does the $\tilde\chi^0_2 \,\tilde\chi^\pm_1$ cross section increase in the focus point region?
The focus point is an interesting region of the cMSSM parameter space at high $m_0$ and low $m_{1/2}$. Features are high scalar masses (> 1-2 TeV), light charginos / neutralinos (which are higgsino-...
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RGEs of the MSSM - problems with Mathematica [closed]
I'm having some troubles with the trilinear soft couplings of the MSSM RGEs. I've used the ones written in Martin's supersymmetry primer and I run them using mathematica, if I do so without taking ...
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Plot of gauge coupling unification [closed]
(Zoom in here to see the scales.)
About the result of plotting running of 3 coupling constant, we think that we should get the correct one(MSSM).
But we get discontinuity at $ M_{susy}$.
If there ...
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Feynman rules for SUSY
This might be an incredibly naive question, but I'm wondering if there are a set of rules for "translating" between Standard Model and SUSY. For instance, if I want want to go from a Standard Model ...
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In MSSM, are the higgs fields eaten by Z,W scalars or pseudoscalars?
I am very puzzled by the quintet of Higgs bosons in the MSSM: two charged, two scalars and a pseudoscalar. I wonder if they could be understood better if they were considered jointly with the three "...
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Does the Photino have mass or is it mass-less like the photon
Does the photino in super-symmetry have a mass, Or is this different in different super symmetric models?
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Why is the lightest Higgs not a free parameter in SUSY?
In the Standard Model, the Higgs mass doesn't really have any theoretical constraints. It could have basically any value and nothing 'breaks'.
However, in MSSM models, we often see the tree level ...
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Missing transverse energy, exact definition
This might seem basic, but it is a bit confusing. You hear about missing transverse energy a lot in SUSY searches due to the LSP which cannot be detected.
Let's say I have the 4-vector for the LSP. ...
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Is a 125 GeV Higgs large (or small) for the MSSM?
As far I as I know, and from naturalness considerations, a 125 GeV Higgs mass is rather large for the MSSM. This is because in the MSSM $$m_h^2 \lesssim M_z^2 \cos^22\beta + \Delta$$ where $\Delta$ ...
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mSUGRA boundary conditions and the MSSM
I read that in the MSSM with mSUGRA boundary conditions, the mass spectrum of the model is determined by five parameters at the GUT scale: $m_0$ (universal scalar mass), $m_{1/2}$ (universal gaugino ...
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Where does the hidden supersymmetric sector of the MSSM come from?
At the end of Chapter 14 of the "Supersymmetry Demystified book" from Patrick Labelle it is mentioned that to constrain the number of allowed softly SUSY breaking terms, a shadow or hidden ...
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Status of the little hierarchy problem
What is the current thinking on the little hierarchy problem in light of a potential Higgs mass above 120 GeV? A few years ago, at least, I remember various phenomenologists saying that this at least ...
Aaron
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Pauli-Villars (PV) regularisation breaks supersymmetry. How to see that?
Does the PV regulator breaks SUSY?
Take for instance the 1-loop (top/stop loops) correction to the Higgs squared-mass parameter in the MSSM, and you'll get something like,
$$\delta m^2_{h_u} = - ...
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Which is the coupling between the photon and the SU(2)xU(1) gauginos, before symmetry breaking?
The photon field is the non chiral piece of SU(2)xU(1), independently of symmetry breaking or not, isn't it?
But before symmetry breaking, each gauge boson has only a chiral gaugino as superpartner....
user135