Electroweak Effective Lagrangians

Wudka, José

doi:10.1142/s0217751x94000959

Cited by 125 publications

(156 citation statements)

References 44 publications

Supporting

Mentioning

154

Contrasting

Unclassified

Order By: Relevance

“…These operators form a redundant basis that is reducible through field redefinitions, or equivalently the equations of motion, that have no effect on the S-matrix [44][45][46][47][48][49]. Following [88], we may eliminate the operators…”

Section: Jhep03(2015)157mentioning

confidence: 99%

“…In this case, the new physics may be analyzed in the decoupling limit [42], and its effects may be parameterized in terms of higher-dimensional operators composed of Standard Model fields [43]. Using the equations of motions reduces the number of independent operators [44][45][46][47][48][49], with a complete non-redundant set first categorised in [50]. This is the effective Standard Model approach adopted in a large number of recent papers 1 , and there have been many analyses of the constraints imposed on new physics via upper limits on the coefficients of a complete dimension-6 operator basis [84][85][86][87][88][89], in particular.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The effective Standard Model after LHC Run I

Ellis

Sanz

You

2015

J. High Energ. Phys.

161

176

View full text Add to dashboard Cite

Abstract:We treat the Standard Model as the low-energy limit of an effective field theory that incorporates higher-dimensional operators to capture the effects of decoupled new physics. We consider the constraints imposed on the coefficients of dimension-6 operators by electroweak precision tests (EWPTs), applying a framework for the effects of dimension-6 operators on electroweak precision tests that is more general than the standard S, T formalism, and use measurements of Higgs couplings and the kinematics of associated Higgs production at the Tevatron and LHC, as well as triple-gauge couplings at the LHC. We highlight the complementarity between EWPTs, Tevatron and LHC measurements in obtaining model-independent limits on the effective Standard Model after LHC Run 1. We illustrate the combined constraints with the example of the two-Higgs doublet model.

show abstract

Section: Jhep03(2015)157mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

The effective Standard Model after LHC Run I

Ellis

Sanz

You

2015

J. High Energ. Phys.

161

176

View full text Add to dashboard Cite

show abstract

“…In constructing the effective Lagrangian, we will eliminate operators that vanish when dim-4 equations of motion are imposed, since they give no contribution to on-shell matrix elements, both in perturbation theory (to all orders) and beyond [3][4][5][6][7][8]; we call such operators redundant. A given type of heavy physics may generate a basis of operators different from the one listed below; such a basis may be transformed in the one we use by applying equations of motion.…”

Section: Jhep05(2015)116mentioning

confidence: 99%

“…Many operators of the form νSM × DM are redundant through the application of the equations of motion [3][4][5][6][7][8], and should be omitted from the basis. Below we provide an illustration of this process of elimination; the notation we use is the following.…”

Section: Jhep05(2015)116mentioning

confidence: 99%

Classification of effective operators for interactions between the Standard Model and dark matter

Duch

Grza̧dkowski

Wudka

2015

J. High Energ. Phys.

View full text Add to dashboard Cite

We construct a basis for effective operators responsible for interactions between the Standard Model and a dark sector composed of particles with spin ≤ 1. Redundant operators are eliminated using dim-4 equations of motion. We consider simple scenarios where the dark matter components are stabilized against decay by Z 2 symmetries. We determine operators which are loop-generated within an underlying theory and those that are potentially tree-level generated.

show abstract

“…Proceedings of the Corfu Summer Institute 2012 "School and Workshops on Elementary Particle Physics and Gravity" September [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27]2012 Corfu, Greece…”

mentioning

confidence: 99%

Neutrinoless double b decay with small neutrino masses

Águila¹,

Aparici²,

Bhattacharya³

et al. 2013

Proceedings of Proceedings of the Corfu Summer Institute 2012 — PoS(Corfu2012)

View full text Add to dashboard Cite

If the only contribution to neutrinoless double beta decay (0νβ β ) are neutrino masses its discovery may be very difficult, especially if neutrinos present a normal hierarchy spectrum. However, this is not the only possibility; 0νβ β can in general produce electrons of either chirality, in contrast with the neutrino induced 0νβ β which predicts two left-handed electrons. Using an effective Lagrangian approach we classify the lepton number violating (LNV) effective operators with two leptons of either chirality but no quarks, ordered according to the magnitude of their contribution to 0νβ β . We point out that, for each of the three chirality assignments, e L e L , e L e R and e R e R , there is only one LNV operator of the corresponding type to lowest order, and these have dimensions 5, 7 and 9, respectively. Neutrino masses are always induced by these extra operators but can be delayed to one (dimension 7) or two loops (dimension 9). Under the assumption that 0νβ β is dominated by the operators of dimension 7 or 9 we find that the scale of new physics should be relatively low ( 30 TeV). We also list the SM additions generating these operators upon integration of the heavy modes, and discuss simple realistic examples of renormalizable theories for each case. The phenomenology of a model giving rise to the dimension 9 operator has been analyzed with some detail: if 0νβ β is going to be seen in the next round of experiments, the doubly charged scalars of the model could be seen at the LHC and lepton flavour violating (LFV) rates could be at the reach of foreseen experiments. Moreover neutrino masses, which arise at two loops, display a very particular structure and are strongly constrained, in fact, sin 2 θ 13 0.008, when µ → eee is required to lie below its present experimental limit.

show abstract

Electroweak Effective Lagrangians

Abstract: In this paper I review several aspects of the use of effective lagrangians in (mainly) electroweak physics. The conditions under which this approach is reliable and useful, as well as the limitations of the formalism are detailed. Various applications are also presented. 42

Cited by 125 publications

References 44 publications

The effective Standard Model after LHC Run I

The effective Standard Model after LHC Run I

Classification of effective operators for interactions between the Standard Model and dark matter

Neutrinoless double b decay with small neutrino masses

Contact Info

Product

Resources

About