ترغب بنشر مسار تعليمي؟ اضغط هنا

Dalitz plot analysis of $B^0 to overline{D}^0 pi^+pi^-$ decays

196   0   0.0 ( 0 )
 نشر من قبل Wenbin Qian
 تاريخ النشر 2015
  مجال البحث
والبحث باللغة English




اسأل ChatGPT حول البحث

The resonant substructures of $B^0 to overline{D}^0 pi^+pi^-$ decays are studied with the Dalitz plot technique. In this study a data sample corresponding to an integrated luminosity of 3.0 fb$^{-1}$ of $pp$ collisions collected by the LHCb detector is used. The branching fraction of the $B^0 to overline{D}^0 pi^+pi^-$ decay in the region $m(overline{D}^0pi^{pm})>2.1$ GeV$/c^2$ is measured to be $(8.46 pm 0.14 pm 0.29 pm 0.40) times 10^{-4}$, where the first uncertainty is statistical, the second is systematic and the last arises from the normalisation channel $B^0 to D^*(2010)^-pi^+$. The $pi^+pi^-$ S-wave components are modelled with the Isobar and K-matrix formalisms. Results of the Dalitz plot analyses using both models are presented. A resonant structure at $m(overline{D}^0pi^-) approx 2.8$ GeV$/c^{2}$ is confirmed and its spin-parity is determined for the first time as $J^P = 3^-$. The branching fraction, mass and width of this structure are determined together with those of the $D^*_0(2400)^-$ and $D^*_2(2460)^-$ resonances. The branching fractions of other $B^0 to overline{D}^0 h^0$ decay components with $h^0 to pi^+pi^-$ are also reported. Many of these branching fraction measurements are the most precise to date. The first observation of the decays $B^0 to overline{D}^0 f_0(500)$, $B^0 to overline{D}^0 f_0(980)$, $B^0 to overline{D}^0 rho(1450)$, $B^0 to D_3^*(2760)^- pi^+$ and the first evidence of $B^0 to overline{D}^0 f_0(2020)$ are presented.



قيم البحث

اقرأ أيضاً

The resonant substructure of $B_s^0 rightarrow bar{D}^0 K^- pi^+$ decays is studied with the Dalitz plot analysis technique. The study is based on a data sample corresponding to an integrated luminosity of $3.0,{rm fb}^{-1}$ of $pp$ collision data re corded by LHCb. A structure at $m(bar{D}^0 K^-) approx 2.86 {rm GeV}/c^2$ is found to be an admixture of spin-1 and spin-3 resonances. The masses and widths of these states and of the $D^*_{s2}(2573)^-$ meson are measured, as are the complex amplitudes and fit fractions for all the $bar{D}^0 K^-$ and $K^-pi^+$ components included in the amplitude model. In addition, the $D^*_{s2}(2573)^-$ resonance is confirmed to be spin-2.
We perform an analysis of the $D^+ to K^0_S pi^+ pi^0$ Dalitz plot using a data set of 2.92 fb$^{-1}$ of $e^+e^-$ collisions at the $psi(3770)$ mass accumulated by the BESIII Experiment, in which 166694 candidate events are selected with a background of 15.1%. The Dalitz plot is found to be well-represented by a combination of six quasi-two-body decay channels ($K^0_Srho^+$, $K^0_Srho(1450)^+$, $overline{K}^{*0}pi^+$, $overline{K}_0(1430)^0pi^+$, $overline{K}(1680)^0pi^+$, $overline{kappa}^0pi^+$) plus a small non-resonant component. Using the fit fractions from this analysis, partial branching ratios are updated with higher precision than previous measurements.
Using a low-background sample of $2.6times 10^5$ $J/psirightarrowomegaeta(omegarightarrowpi^{+}pi^{-}pi^{0},etarightarrowgammagamma)$ events, about 5 times larger statistics than previous experiments, we present a Dalitz plot analysis of the decay $o megarightarrowpi^{+}pi^{-}pi^{0}$. It is found that the Dalitz plot distribution differs from the pure $P$-wave phase space with a statistical significance of $18.9sigma$. The parameters from the fit to data are in reasonable agreement with those without the cross-channel effect within the dispersive framework, which indicates that the cross-channel effect in $omegarightarrowpi^+pi^-pi^0$ is not significant.
The first study is presented of CP violation with an amplitude analysis of the Dalitz plot of $B^0 to D K^+ pi^-$ decays, with $D to K^+ pi^-$, $K^+ K^-$ and $pi^+ pi^-$. The analysis is based on a data sample corresponding to $3.0,{rm fb}^{-1}$ of $ pp$ collisions collected with the LHCb detector. No significant CP violation effect is seen, and constraints are placed on the angle $gamma$ of the unitarity triangle formed from elements of the Cabibbo-Kobayashi-Maskawa quark mixing matrix. Hadronic parameters associated with the $B^0 to D K^*(892)^0$ decay are determined for the first time. These measurements can be used to improve the sensitivity to $gamma$ of existing and future studies of the $B^0 to D K^*(892)^0$ decay.
We report a measurement of the amplitude ratio $r_S$ of $B^0 to D^0K^{*0}$ and $B^0 to bar{D^0}K^{*0}$ decays with a model-independent Dalitz plot analysis using $Dto K_S^0pi^+pi^-$ decays. Using the full data sample of $772times10^6$ $Bbar{B}$ pairs collected at the $Upsilon(4S)$ resonance with the Belle detector at KEKB accelerator the upper limit is $r_S < 0.87$ at the 68 % confidence level. This result is the first measurement of $r_S$ with a model-independent Dalitz analysis, and is consistent with results from other analyses. The value of $r_S$ indicates the sensitivity of the decay to $phi_3$ because the statistical uncertainty is proportional to $1/r_S$. The $r_S$ result is obtained from observables ($x_pm$, $y_pm$) begin{eqnarray} x_- &=& +0.4 ^{+1.0 +0.0}_{-0.6 -0.1} pm0.0 y_- &=& -0.6 ^{+0.8 +0.1}_{-1.0 -0.0} pm0.1 x_+ &=& +0.1 ^{+0.7 +0.0}_{-0.4 -0.1} pm0.1 y_+ &=& +0.3 ^{+0.5 +0.0}_{-0.8 -0.1} pm0.1 , end{eqnarray} where $x_pm = r_S cos(delta_S pm phi_3)$, $y_pm = r_S sin(delta_S pm phi_3)$ and $phi_3 (delta_S)$ are the weak (strong) phase difference between $B^0 to D^0K^{*0}$ and $B^0 to bar{D^0}K^{*0}$. The first uncertainty is statistical, the second is the experimental systematic and the third is the systematic due to the uncertainties on $c_i$ and $s_i$ parameters measured by CLEO.
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