ترغب بنشر مسار تعليمي؟ اضغط هنا

Gauged $L^{}_{mu}{-}L^{}_{tau}$ at a muon collider

111   0   0.0 ( 0 )
 نشر من قبل Guo-Yuan Huang
 تاريخ النشر 2021
  مجال البحث
والبحث باللغة English




اسأل ChatGPT حول البحث

We investigate the sensitivity of the projected TeV muon collider to the gauged $L^{}_{mu}$-$L^{}_{tau}$ model. Two processes are considered: $Z$-mediated two-body scatterings $mu^+ mu^- to ell^+ ell^-$ with $ell = mu$ or $tau$, and scattering with initial state photon emission, $mu^+ mu^- to gamma Z,~Z to ell overline{ell}$, where $ell$ can be $mu$, $tau$ or $ u_{mu/tau}$. We quantitatively study the sensitivities of these two processes by taking into account possible signals and relevant backgrounds in a muon collider experiment with a center-of-mass energy $sqrt{s} = 3~{rm TeV}$ and a luminosity $L=1~{rm ab^{-1}}$. For two-body scattering one can exclude $Z$ masses $M^{}_{Z} lesssim 100~{rm TeV}$ with $mathcal{O}(1)$ gauge couplings. When $M^{}_{Z} lesssim 1~{rm TeV} <sqrt{s}$, one can exclude $g gtrsim 2times 10^{-2}$. The process with photon emission is more powerful than the two-body scattering if $M^{}_{Z} < sqrt{s}$. For instance, a sensitivity of $g simeq 4 times 10^{-3}$ can be achieved at $M^{}_{Z} = 1~{rm TeV}$. The parameter spaces favored by the $(g-2)^{}_{mu}$ and $B$ anomalies with $M^{}_{Z} > 100~{rm GeV}$ are entirely covered by a muon collider.



قيم البحث

اقرأ أيضاً

In this paper we present a novel formulation of chaotic hybrid inflation in supergravity. The model includes a waterfall field which spontaneously breaks a gauged $U_1(B-L)$ at a GUT scale. This allows for the possibility of future model building whi ch includes the standard formulation of baryogenesis via leptogenesis with the waterfall field decaying into right-handed neutrinos. We have not considered the following issues in this short paper, i.e. supersymmetry breaking, dark matter or the gravitino or moduli problems. Our focus is on showing the compatibility of the present model with Planck, WMAP and Bicep2 data.
We explore muon anomalous magnetic moment (muon $g-2$) in a scotogenic neutrino model with a gauged lepton numbers symmetry $U(1)_{mu-tau}$. In this model, a dominant muon $g-2$ contribution comes from not an additional gauge sector but the Yukawa se ctor. In our numerical $Delta chi^2$ analysis, we show that our model is in favor of normal hierarchy with some features. We also demonstrate two benchmark points, satisfying muon $g-2$ at the best fit value $25.1times10^{-10}$.
We analyze a model with unbroken B-L gauge symmetry where neutrino masses are generated at one loop, after spontaneous breaking of a global U(1) symmetry. These symmetries ensure dark matter stability and the Diracness of neutrinos. Within this conte xt, we examine fermionic dark matter. Consistency between the required neutrino mass and the observed relic abundance indicates dark matter masses and couplings within the reach of direct detection experiments.
This report was prepared in the context of the LPCC Electroweak Precision Measurements at the LHC WG and summarizes the activity of a subgroup dedicated to the systematic comparison of public Monte Carlo codes, which describe the Drell-Yan processes at hadron colliders, in particular at the CERN Large Hadron Collider (LHC). This work represents an important step towards the definition of an accurate simulation framework necessary for very high-precision measurements of electroweak (EW) observables such as the $W$ boson mass and the weak mixing angle. All the codes considered in this report share at least next-to-leading-order (NLO) accuracy in the prediction of the total cross sections in an expansion either in the strong or in the EW coupling constant. The NLO fixed-order predictions have been scrutinized at the technical level, using exactly the same inputs, setup and perturbative accuracy, in order to quantify the level of agreement of different implementations of the same calculation. A dedicated comparison, again at the technical level, of three codes that reach next-to-next-to-leading-order (NNLO) accuracy in quantum chromodynamics (QCD) for the total cross section has also been performed. These fixed-order results are a well-defined reference that allows a classification of the impact of higher-order sets of radiative corrections. Several examples of higher-order effects due to the strong or the EW interaction are discussed in this common framework. Also the combination of QCD and EW corrections is discussed, together with the ambiguities that affect the final result, due to the choice of a specific combination recipe.
The LHCb measurements of the $mu / e$ ratio in $B to K ell ell$ decays $(R_{K^{}})$ indicate a deficit with respect to the Standard Model prediction, supporting earlier hints of lepton universality violation observed in the $R_{K^{(*)}}$ ratio. Possi ble explanations of these $B$-physics anomalies include heavy $Z$ bosons or leptoquarks mediating $b to s mu^+ mu^- $. We note that a muon collider can directly measure this process via $mu^+ mu^- to b bar s$ and can shed light on the lepton non-universality scenario. Investigating currently discussed center-of-mass energies $sqrt{s} = 3$, 6 and 10 TeV, we show that the parameter space of $Z$ and $S_3$ leptoquark solutions to the $R_{K^{(*)}}$ anomalies can be mostly covered. Effective operators explaining the anomalies can be probed with the muon collider setup $sqrt{s} = 6~{rm TeV}$ and integrated luminosity $L = 4~{rm ab^{-1}}$.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا