scholarly journals Probing the Effects of New Physics in B¯⁎→Plν¯l Decays

2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Qin Chang ◽  
Jie Zhu ◽  
Na Wang ◽  
Ru-Min Wang
Keyword(s):  
Spin Asymmetry ◽  
Branching Fraction ◽  
New Physics ◽  
Heavy Flavor ◽  
Independent Vector ◽  
Vector Type ◽  
Scalar Type ◽  
The Future ◽  
Significant Divergence ◽  
Model Independent

The significant divergence between the SM predictions and experimental measurements for the ratios, RD(⁎)≡B(B¯→D(⁎)τ-ν¯τ)/B(B¯→D(⁎)l′-ν¯l′) with (l′=e,μ), implies possible hint of new physics in the flavor sector. In this paper, motivated by the “RD(⁎) puzzle” and abundant B⁎ data samples at high-luminosity heavy-flavor experiments in the future, we try to probe possible effects of new physics in the semileptonic B¯u,d,s⁎→Pl-ν¯l  (P=D,Ds,π,K) decays induced by b→(u,c)l-ν¯l transitions in the model-independent vector and scalar scenarios. Using the spaces of NP parameters obtained by fitting to the data of RD and RD⁎, the NP effects on the observables including branching fraction, ratio RP⁎, lepton spin asymmetry, and lepton forward-backward asymmetry are studied in detail. We find that the vector type couplings have large effects on the branching fraction and ratio RP⁎. Meanwhile, the scalar type couplings provide significant contributions to all of the observables. The future measurements of these observables in the B¯⁎→Pl-ν¯l decays at the LHCb and Belle-II could provide a way to crosscheck the various NP solutions to the “RD(⁎) puzzle”.

scholarly journals On measurement of photon polarization in radiative penguin B decays to baryons

2021 ◽  
Vol 81 (8) ◽  
Author(s):  
P. Pakhlov ◽  
T. Uglov
Keyword(s):  
Standard Model ◽  
Standard Model Prediction ◽  
Branching Fraction ◽  
New Physics ◽  
Photon Polarization ◽  
Left Handed ◽  
The Standard Model ◽  
Stringent Test ◽  
Model Independent ◽  
Near Future

AbstractA measurement of the photon polarization in radiative penguin B decays provides a test of the Standard Model and a probe for New Physics, that can lead to a deviation from the Standard Model prediction of left-handed photons in $$b\rightarrow s \gamma $$ b → s γ . We propose a new method to measure the photon polarization using the baryonic decay $$B^- \rightarrow \Lambda \bar{p} \gamma $$ B - → Λ p ¯ γ . The P-violating $$\Lambda $$ Λ -hyperon decay allows a measurement of the $$\Lambda $$ Λ helicity to be performed, which can be uniquely related to the photon polarization in a model-independent way. The $$B^- \rightarrow \Lambda \bar{p} \gamma $$ B - → Λ p ¯ γ decay was recently measured to have a large branching fraction providing a possibility to get meaningful results with the data already available at LHC and B-factory experiments. An increase of the B-meson sample at high luminosity LHC experiments and Belle II should provide a really stringent test by using this method already in the near future.

scholarly journals A comprehensive study on the semileptonic decay of heavy flavor mesons

2021 ◽  
Vol 2021 (2) ◽  
Author(s):  
Lu Zhang ◽  
Xian-Wei Kang ◽  
Xin-Heng Guo ◽  
Ling-Yun Dai ◽  
Tao Luo ◽  
...  
Keyword(s):  
Vector Meson ◽  
Quark Model ◽  
Semileptonic Decay ◽  
Branching Fraction ◽  
Form Factors ◽  
Good Control ◽  
New Physics ◽  
Mean Value ◽  
Heavy Flavor ◽  
Final State

Abstract The semileptonic decay of heavy flavor mesons offers a clean environment for extraction of the Cabibbo-Kobayashi-Maskawa (CKM) matrix elements, which describes the CP-violating and flavor changing process in the Standard Model. The involved form factors where the dynamical information is encoded play an essential role in achieving any conclusive statement. That is, the knowledge of the form factors should be under good control, requiring one to examine more observables in addition to the branching fraction. In this paper, we provide the mean value and the q2-dependent shape for further observables [differential decay distribution (dΓ/dq2), forward-backward asymmetry $$ \left({\mathcal{A}}_{FB}^{ls}\right) $$ A FB ls , longitudinal $$ \left({P}_L^l\right) $$ P L l and transverse $$ \left({P}_T^l\right) $$ P T l polarization of a charged lepton, longitudinal polarization of a vector meson in the final state $$ \left({F}_L^l(V)\right) $$ F L l V , leptonic convexity parameter $$ \left({C}_F^l\right) $$ C F l , and trigonometric moments $$ \left({W}_i^l\right) $$ W i l in the decay of D(s) and B(s) to P/Vl+νl (l = e, μ or τ)], based on the predictions of the relevant form factors from the covariant light-front quark model. P and V denote the pseudoscalar and vector meson, respectively. As a comparison, we find a good agreement with the results from the covariant confining quark model and the relativistic quark model in the literature. As it has been observed that the $$ {P}_L^l $$ P L l and $$ {F}_L^l(V) $$ F L l V are crucial quantities to discriminate various New Physics models, the reexamination of these observables from a different method is also essential and necessary.

Reflections into the Spirit of the Islamic Corpus of Knowledge and the Rise of the New Science

1993 ◽  
Vol 10 (2) ◽  
pp. 153-164
Author(s):  
Mahmoud Dhaouadi
Keyword(s):  
Social Sciences ◽  
Third World ◽  
New Physics ◽  
Western Civilization ◽  
Western Science ◽  
New Science ◽  
Scientific Disciplines ◽  
The World ◽  
The Future ◽  
Primary Reference

There is no question that contemporary western civilization has beendominant in the field of science since the Renaissance. Western scientificsuperiority is not limited to specific scientific disciplines, but is rather anovetall scientific domination covering both the so-called exact and thehuman-social sciences. Western science is the primary reference for specialistsin such ateas as physics, chemistry, biology, medicine, economics,psychology, and sociology. It is in this sense that Third World underdevelopmentis not only economic, social, and industrial; it also suffersfrom scientific-cultutal underdevelopment, or what we call "The OtherUnderdevelopment" (Dhaouadi 1988).The imptessive progress of western science since Newton and Descartesdoes not meari, however, that it has everything tight or perfect. Infact, its flaws ate becoming mote visible. In the last few decades, westernscience has begun to experience a shift from what is called classical scienceto new science. Classical science was associated with the celestialmechanics of Copernicus, Kepler, Newton, the new physics of Galileo,and the philosophy of Descartes. Descartes introduced a radical divisionbetween mind and matter, while Newton and his fellows presented a newscience that looked at the world as a kind of giant clock The laws of thisworld were time-reversible, for it was held that there was no differencebetween past and future. As the laws were deterministic, both the pastand the future could be predicted once the present was known.The vision of the emerging new science tends to heal the division betweenmatter and spirit and to do away with the mechanical dimension ...

scholarly journals Disentangling QCD and new physics in D → πℓ+ℓ−

2021 ◽  
Vol 2021 (4) ◽  
Author(s):  
Aoife Bharucha ◽  
Diogo Boito ◽  
Cédric Méaux
Keyword(s):  
Standard Model ◽  
Branching Ratio ◽  
Branching Ratios ◽  
New Physics ◽  
Operator Product ◽  
Beyond The Standard Model ◽  
Spectral Functions ◽  
The Standard Model ◽  
Model Independent ◽  
Weak Annihilation

Abstract In this paper we consider the decay D+ → π+ℓ+ℓ−, addressing in particular the resonance contributions as well as the relatively large contributions from the weak annihilation diagrams. For the weak annihilation diagrams we include known results from QCD factorisation at low q2 and at high q2, adapting the existing calculation for B decays in the Operator Product Expansion. The hadronic resonance contributions are obtained through a dispersion relation, modelling the spectral functions as towers of Regge-like resonances in each channel, as suggested by Shifman, imposing the partonic behaviour in the deep Euclidean. The parameters of the model are extracted using e+e− → (hadrons) and τ → (hadrons) + ντ data as well as the branching ratios for the resonant decays D+ → π+R(R → ℓ+ℓ−), with R = ρ, ω, and ϕ. We perform a thorough error analysis, and present our results for the Standard Model differential branching ratio as a function of q2. Focusing then on the observables FH and AFB, we consider the sensitivity of this channel to effects of physics beyond the Standard Model, both in a model independent way and for the case of leptoquarks.

SEARCH FOR NEW PHYSICS IN eμX DATA AT THE TEVATRON USING SLEUTH: A QUASI-MODEL-INDEPENDENT SEARCH STRATEGY FOR NEW PHYSICS

2001 ◽  
Vol 16 (supp01b) ◽  
pp. 888-890
Author(s):  
◽  
BRUCE KNUTESON
Keyword(s):  
Standard Model ◽  
Search Strategy ◽  
New Physics ◽  
Beyond The Standard Model ◽  
Final States ◽  
Final State ◽  
The Standard Model ◽  
Model Independent

We present a quasi-model-independent search for physics beyond the standard model. We define final states to be studied, and construct a rule that identifies a set of variables appropriate for any particular final state. A new algorithm ("Sleuth") searches for regions of excess in the space of those variables and quantifies the significance of any detected excess. After demonstrating the sensititvity of the method, we apply it to the semi-inclusive channel eμX collected in ≈108 pb -1 of [Formula: see text] collisions at [Formula: see text] at the DØ experiment at the Fermilab Tevatron. We find no evidence of new high pT physics in this sample.

scholarly journals Non-standard interactions in SMEFT confronted with terrestrial neutrino experiments

2021 ◽  
Vol 2021 (3) ◽  
Author(s):  
Yong Du ◽  
Hao-Lin Li ◽  
Jian Tang ◽  
Sampsa Vihonen ◽  
Jiang-Hao Yu
Keyword(s):  
Neutrino Oscillation ◽  
New Physics ◽  
Effective Field ◽  
Scalar Leptoquark ◽  
Double Chooz ◽  
The Standard Model ◽  
Reactor Neutrino ◽  
Model Independent ◽  
Neutrino Experiments ◽  
Individual Dimension

Abstract The Standard Model Effective Field Theory (SMEFT) provides a systematic and model-independent framework to study neutrino non-standard interactions (NSIs). We study the constraining power of the on-going neutrino oscillation experiments T2K, NOνA, Daya Bay, Double Chooz and RENO in the SMEFT framework. A full consideration of matching is provided between different effective field theories and the renormalization group running at different scales, filling the gap between the low-energy neutrino oscillation experiments and SMEFT at the UV scale. We first illustrate our method with a top- down approach in a simplified scalar leptoquark model, showing more stringent constraints from the neutrino oscillation experiments compared to collider studies. We then provide a bottom-up study on individual dimension-6 SMEFT operators and find NSIs in neutrino experiments already sensitive to new physics at ∼20 TeV when the Wilson coefficients are fixed at unity. We also investigate the correlation among multiple operators at the UV scale and find it could change the constraints on SMEFT operators by several orders of magnitude compared with when only one operator is considered. Furthermore, we find that accelerator and reactor neutrino experiments are sensitive to different SMEFT operators, which highlights the complementarity of the two experiment types.

scholarly journals Model-independent constraints on new physics in b → s transitions

2012 ◽  
Vol 2012 (4) ◽  
Author(s):  
Wolfgang Altmannshofer ◽  
Paride Paradisi ◽  
David M. Straub
Keyword(s):  
New Physics ◽  
Model Independent

scholarly journals Sensitivity on the electromagnetic dipole moments of the tau-lepton at the CLIC

2019 ◽  
Author(s):  
MARIA HERNANDEZ ◽  
Ahmet A. Billur ◽  
Murat Köksal ◽  
Alejandro Gutiérrez-Rodríguez
Keyword(s):  
Electric Dipole ◽  
Linear Collider ◽  
Dipole Moments ◽  
Tau Lepton ◽  
Good Prospect ◽  
Electric Dipole Moments ◽  
Systematic Uncertainties ◽  
The Future ◽  
Model Independent

In this paper we established model independent bounds on the anomalous magnetic and electric dipole moments of the tau-lepton using the process \mathbf{\gamma\gamma \to \tau^+\tau^-}𝛄𝛄→𝛕+𝛕−. We use data collected with the future \mathbf{e^+ e^-}𝐞+𝐞− linear collider such as the CLIC at \mathbf{\sqrt{s}}𝐬 = 380, 1500, 3000 GeV, and we consider systematic uncertainties of \mathbf{\delta_{sys}}𝛅𝐬𝐲𝐬 = 0\%%, 3\%%, 5\%%. The theory predictions are a very good prospect for probing the dipole moments of the tau-lepton at the future \mathbf{e^ + e^-}𝐞+𝐞− linear collider at the \mathbf{\gamma\gamma}𝛄𝛄 mode.

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