English
Related papers

Related papers: New physics solutions for $R_D$ and $R_{D^*}$

200 papers

Current experimental information on the charm meson decay observables in which the $c\to s\ell\nu_\ell$ transitions occur is well compatible with the Standard Model predictions. Recent precise lattice calculations of the $D_s$ meson decay…

High Energy Physics - Phenomenology · Physics 2015-05-13 Svjetlana Fajfer , Ivan Nisandzic , Ursa Rojec

It is well known that New Physics can contribute to weak decays of heavy mesons via virtual processes during its decays. The discovery of New Physics, using such decays is made difficult due to intractable strong interaction effects needed…

High Energy Physics - Phenomenology · Physics 2013-05-30 Diganta Das , Rahul Sinha

We perform a comprehensive study of the impact of new-physics operators with different Lorentz structures on decays involving the b -> s mu+ mu- transition. We examine the effects of new vector-axial vector (VA), scalar-pseudoscalar (SP)…

High Energy Physics - Phenomenology · Physics 2015-05-19 Ashutosh Kumar Alok , Alakabha Datta , Amol Dighe , Murugeswaran Duraisamy , Diptimoy Ghosh , David London

The discovery of New Physics, using weak decays of mesons is difficult due to intractable strong interaction effects needed to describe it. We show how the multitude of "related observables" obtained from B\to K^* \ell^+\ell^-, can provide…

High Energy Physics - Phenomenology · Physics 2012-02-24 Diganta Das , Rahul Sinha

We propose two different and complementary observables for singling out possible signals of physics beyond the standard model in the semi-leptonic decays $\Lambda_b \to \Lambda_c \ell{\bar \nu}_{\ell}$, both with the $\tau$ lepton and with…

High Energy Physics - Phenomenology · Physics 2017-03-21 Elvio Di Salvo , Ziad J. Ajaltouni

We perform a data-driven analysis of new physics (NP) effects in exclusive $b \to s \ell^+\ell^-$ decays in a model-independent effective theory approach with dimension six operators considering scalar, pseudo-scalar, vector and…

High Energy Physics - Phenomenology · Physics 2021-07-09 Aritra Biswas , Soumitra Nandi , Ipsita Ray , Sunando Kumar Patra

Recent experimental results on exclusive semi-tauonic B meson decays, B -> D(*) tau nu, showing sizable deviations from the standard model prediction, suggest a new physics in which the structure of the relevant weak charged interaction may…

High Energy Physics - Phenomenology · Physics 2013-03-14 Minoru Tanaka , Ryoutaro Watanabe

We discuss the possibilities of extracting the constraints on New Physics by using the current data on the leptonic and semileptonic decays of pseudoscalar mesons. In doing so we use a general low energy Lagrangian that besides the vector…

High Energy Physics - Phenomenology · Physics 2021-05-20 Damir Bečirević , Florentin Jaffredo , Ana Peñuelas , Olcyr Sumensari

One of the exciting results in flavor physics in recent times is the $R_D$/$R_{D^*}$ puzzle. The measurements of these flavor ratios performed by the B-factory experiments, BaBar and Belle, and the LHCb experiment are about $4\sigma$ away…

High Energy Physics - Phenomenology · Physics 2018-07-31 Ashutosh Kumar Alok , Dinesh Kumar , Suman Kumbhakar , S Uma Sankar

Recently several measurements in the neutral current sector $b\rightarrow s l^+l^-$ ($l=e$ or $\mu$) as well as in the charged current sector $b \rightarrow c \tau \bar{\nu}$ show significant deviations from their Standard Model…

High Energy Physics - Phenomenology · Physics 2019-05-22 Suman Kumbhakar , Jyoti Saini

Physics beyond the Standard Model could be measured indirectly, through its effects on Standard Model observables. One place to look for such effects is in the semileptonic decays of B mesons. In order to constrain the possible role of new…

High Energy Physics - Phenomenology · Physics 2007-05-23 Walter D. Goldberger

We perform a model-independent analysis of $|\Delta b|=|\Delta d|=1$ processes to test the standard model and probe flavor patterns of new physics. Constraints on Wilson coefficients are obtained from global fits to $B^+ \to \pi^+…

High Energy Physics - Phenomenology · Physics 2023-06-07 Rigo Bause , Hector Gisbert , Marcel Golz , Gudrun Hiller

The Belle Collaboration has measured the complete set of angular coefficient functions for the decays ${\bar B} \to D^*\,(D\,\pi)\,\ell\,{\bar \nu}_{\ell}$, where $\ell = e,\,\mu$, in four bins of the variable $w={m_B^2+m_{D^*}^2-q^2 \over…

High Energy Physics - Phenomenology · Physics 2024-10-22 Nicola Losacco

Recent experimental results on angular observables in the rare decay $B\to K^*\mu^+\mu^-$ show significant deviations from Standard Model predictions. We investigate the possibility that these deviations are due to new physics. Combining…

High Energy Physics - Phenomenology · Physics 2014-09-05 Wolfgang Altmannshofer , David M. Straub

We apply the formalism of amplitude symmetries to the angular distribution of the decays $B \to D^* \ell \nu$ for $\ell=e,\mu,\tau$. We show that the angular observables used to describe the distribution of this class of decays are not…

High Energy Physics - Phenomenology · Physics 2020-07-15 Marcel Algueró , Sébastien Descotes-Genon , Joaquim Matias , Martín Novoa-Brunet

The confirmation of excess in $R_{D^*}$ at the LHCb is an indication of lepton flavor non-universality. Various different new physics operators and their coupling strengths, which provide a good fit to $R_D$, $R_{D^*}$ and $q^2$ spectra,…

High Energy Physics - Phenomenology · Physics 2017-07-31 Ashutosh Kumar Alok , Dinesh Kumar , Suman Kumbhakar , S Uma Sankar

The study of $\bar{B} \to D^* \tau {\bar{\nu}}_\tau$ angular distribution can be used to obtain information about new physics (or beyond the Standard Model) couplings, which are motivated by various $B$ anomalies. However, the inability to…

High Energy Physics - Phenomenology · Physics 2026-04-17 Bhubanjyoti Bhattacharya , Thomas E. Browder , Alakabha Datta , Tejhas Kapoor , Emi Kou , Lopamudra Mukherjee

At Moriond 2019, Belle collaboration announced their new measurements on $R_D$ and $R_{D^*}$ which are in agreement with their Standard Model (SM) predictions within $1.2\sigma$. After inclusion of these measurements, the discrepancy…

High Energy Physics - Phenomenology · Physics 2021-01-07 Suman Kumbhakar , Ashutosh Kumar Alok , Dinesh Kumar , S. Uma Sankar

The BaBar Collaboration has recently reported the measurement of the ratio of the branching fractions of $\bar{B} \to D(D^{*}) \tau^{-} \bar{\nu_\tau}$ to $\bar{B} \to D(D^{*}) \ell^{-} \bar{\nu_\ell}$ which deviates from the Standard Model…

High Energy Physics - Phenomenology · Physics 2018-03-13 Alakabha Datta , Murugeswaran Duraisamy , Diptimoy Ghosh

Through an effective field theory approach, we analyze the new physics corrections to muon and beta decays and their effects on the extractions of V_ud and V_us. Assuming nearly flavor blind NP interactions, we find that the only quantity…

High Energy Physics - Phenomenology · Physics 2010-11-02 Martin Gonzalez-Alonso