Questions tagged [mssm]

MSSM stands for the Minimal Supersymmetric Standard Model.

Filter by
Sorted by
Tagged with
0
votes
1answer
27 views

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 ...
0
votes
1answer
38 views

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
0
votes
0answers
35 views

Where can I find the detailed calculation for the mass of the lights Higgs boson in MSSM?

can somebody mention where the mass of the lights Higgs boson in MSSM (minimal supersymmetric standard model) is discussed? I need a detailed and thorough explanation of the subject mater. I ...
2
votes
1answer
92 views

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 ...
0
votes
2answers
99 views

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?
1
vote
1answer
95 views

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)\...
1
vote
0answers
30 views

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?
0
votes
1answer
1k views

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 ...
3
votes
1answer
60 views

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 ...
4
votes
1answer
183 views

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: ...
4
votes
1answer
274 views

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 ...
2
votes
1answer
309 views

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 (...
2
votes
1answer
436 views

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 ...
4
votes
2answers
204 views

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 ...
4
votes
1answer
303 views

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 ...
3
votes
1answer
104 views

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 ...
1
vote
0answers
147 views

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....
3
votes
2answers
506 views

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)...
4
votes
1answer
96 views

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-...
-1
votes
1answer
456 views

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 ...
1
vote
1answer
483 views

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 ...
6
votes
2answers
1k views

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 ...
4
votes
1answer
181 views

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 "...
4
votes
1answer
1k views

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?
7
votes
1answer
514 views

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 ...
3
votes
2answers
1k views

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. ...
6
votes
1answer
397 views

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 $\Delta$ ...
6
votes
2answers
317 views

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 ...
8
votes
1answer
590 views

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 ...
6
votes
1answer
504 views

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 ...
3
votes
1answer
303 views

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} = - ...
8
votes
1answer
236 views

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....