arXiv subjects

Elnaz Amirkhanlou

Publications and source records attributed to Elnaz Amirkhanlou.

5 recordsLinked to original sources

arXiv2026

Amplitude analysis and branching fraction calculations of $B_c$ meson decays into $B_sπ$, $DKπ$ and $D_sKK$ final state mesons

In this study, several newly observed decay modes of the $B_c^+$ meson of the form $B_c^+\rightarrow Dh^+h^-$, where $D$ denotes a charmed meson and $h^{\pm}$ represents a charged pion or kaon, have been investigated. The decay channels $B_c^+\rightarrow D^{+}K^+π^{-}$, $B_c^+\rightarrow D^{*+}K^+π^{-}$ and $B_c^+\rightarrow D_s^+K^+K^-$ were observed for the first time. The LHCb Collaboration has measured their branching fractions relative to the reference decay $B_c^+\rightarrow B_s^0π^+$, and reported experimental values including $\mathcal{R}^{\exp}(B_c^+\rightarrow D^{+}K^+π^{-})=(1.96\pm0.23\pm0.08\pm0.10)\times 10^{-3}$ , $\mathcal{R}^{\exp}(B_c^+\rightarrow D^{*+}K^+π^{-})=(3.67\pm0.55\pm0.24\pm0.20)\times10^{-3}$ and $\mathcal{R}^{\exp}(B_c^+\rightarrow D_s^+K^+K^{-})=(1.61\pm0.35\pm0.13\pm0.07)\times 10^{-3}$. In this regard, by performing precise calculations using the factorization approach, we have computed similar branching ratio values, including $\mathcal{R}(B_c^+\rightarrow D^{+}K^+π^{-})=(1.70\pm0.08)\times 10^{-3}$, $\mathcal{R}(B_c^+\rightarrow D^{*+}K^+π^{-})=(3.63\pm0.45)\times 10^{-3}$ and $\mathcal{R}(B_c^+\rightarrow D_s^+K^+K^{-})=(1.09\pm0.08)\times 10^{-3}$. The obtained theoretical results show good consistency with the recent experimental measurements reported by the LHCb collaboration, confirming the effectiveness of the factorization formalism in describing these $B_c^+$ decay modes.

hep-ph↗

arXiv2024

Contributions of $ψ_{2}(3823)$ and $ψ(4040)$ charmonium in $B^+\rightarrow J/ψηK^+$ decay

Recently, a study on the $J/ψη$ mass spectrum from $B^+\rightarrow J/ψηK^+$ decays was reported by the LHCb detector. The results of this study are reported as a ratio of branching fractions as $F_{X}\equiv\frac{\mathcal{B}r(B^+\rightarrow XK^+)\times\mathcal{B}r(X\rightarrow J/ψη)}{\mathcal{B}r(B^+\rightarrow ψ(2S) K^+)\times\mathcal{B}r(ψ(2S)\rightarrow J/ψη)}$ for $X=ψ_2(3823),ψ(4040)$, which are $(5.95^{+3.38}_{-2.55})\times10^{-2}$ and $(40.60\pm11.20)\times10^{-2}$, respectively. Also, the products related to $B_{X}\equiv\mathcal{B}r(B^+\rightarrow XK^+)\times\mathcal{B}r(X\rightarrow J/ψη)$ branching fractions are $B_{ψ_2(3823)}=(1.25^{+0.71}_{-0.53}\pm0.04)\times10^{-6}$ and $B_{ψ(4040)}=(8.53\pm2.35\pm0.30)\times10^{-6}$. For the first time, we calculated this branching fraction using factorization. According to our calculations, $F_X$ to be $F_{ψ_{2}(3823)}=(6.55\pm1.88)\times10^{-2}$ and $F_{ψ(4040)}=(14.33\pm4.15)\times10^{-2}$ at $μ=m_b/2$. We have estimated $B_{ψ_{2}(3823)}=(0.26\pm0.05)\times10^{-6}$ at $μ=m_b/2$ and $B_{ψ(4040)}=(2.88\pm0.64)\times10^{-6}$ at $μ=2m_b$.

hep-ph↗

arXiv2023

Analysis of $B^0_s\rightarrow χ_{c1}(3872)π^+π^-$ decay

Recently, the LHCb collaboration has analyzed the decay of $B_s^0\rightarrow χ_{c1}(3872)(\rightarrow J/ψπ^+ π^-) π^+ π^-$ and reported the ratio of the branching fractions to the $B_s^0\rightarrow ψ(2S)(\rightarrow J/ψπ^+π^-)π^+π^-$ decay. The results of this study have measured as a ratio of branching fractions as{\setlength\arraycolsep{.75pt} \begin{eqnarray} \mathcal{R}&=&\frac{\mathcal{B}r(B_s^0\rightarrowχ_{c1}(3872)π^+π^-)\times\mathcal{B}r(χ_{c1}(3872)\rightarrow J/ψπ^+π^-)}{\mathcal{B}r(B_s^0\rightarrowψ(2S)π^+π^-)\times\mathcal{B}r(ψ(2S)\rightarrow J/ψπ^+π^-)}\nonumber\\&=&(6.8\pm1.1\pm0.2)\times10^{-2},\nonumber \end{eqnarray}} and{\setlength\arraycolsep{.75pt} \begin{eqnarray} \mathcal{B_X}&=&\mathcal{B}r(B_s^0\rightarrowχ_{c1}(3872)π^+π^-)\times\mathcal{B}r(χ_{c1}(3872)\rightarrow J/ψπ^+π^-)\nonumber\\&=&(1.6\pm0.3\pm0.1\pm0.3)\times10^{-6}.\nonumber \end{eqnarray}} For the first time, we calculated this branching fraction using factorization. According to our calculations, ratio of branching fractions to be $\mathcal{R}=(4.38\pm1.36)\times10^{-2}$ at $μ=m_b/2$ and the products related to branching fractions have been estimated $\mathcal{B_X}=(1.08\pm0.62)\times10^{-6}$ at $μ=m_b$. The results are consistent with the experiment reported.

hep-ph↗

arXiv2023

Estimated of $CP$ violation in $B^0$ meson decays into $D^{*+}$ and $D^-$ mesons

The decay $B^0\rightarrow D^{*+}D^-$ is favorable mode for studying $CP$ violation in the interference between mixing and decay for $B^0$ and $\bar{B}^0$ mesons. The latest analysis of the $CP$ parameters has been performed by the LHCb collaboration values of $S_{D^*D}=-0.861\pm0.077\pm0.019$, $C_{D^*D}=-0.059\pm0.092\pm0.020$, $\triangle S_{D^*D}=0.019\pm0.075\pm0.012$, $\triangle C_{D^*D}=-0.031\pm0.092\pm0.016$, and $\mathcal{A}_{D^*D}^{CP}=0.008\pm0.014\pm0.006\pm0.003$. We have been estimated the parameters $S_{D^*D}$ and $C_{D^*D}$ of the $B^0\rightarrow D^{*+}D^-$ decay as $-0.709\pm0.024$ and $-0.051\pm0.004$. In the following, we have obtained the values of $\triangle S_{D^*D}=0.054\pm0.003$ and $\triangle C_{D^*D}=0.020\pm0.001$ and direct $CP$ violation of $0.008\pm0.001$. Also, we have calculated the branching ratio of $B^0\rightarrow D^{*+}D^-$ decay. The values obtained in this work are comparable with the corresponding experimental values.

hep-ph↗

arXiv2022

Calculation of branching fraction and $CP$ violation in $B^-\rightarrow D_s^-D^0$ decay

The most precise measurement of the $CP$ asymmetry in the decay $B^-\rightarrow D_s^-D^0$ has been reported by LHCb collaboration with the value of $(-0.4\pm0.5\pm0.5)\%$. In this study, the $CP$ violation in the decay $B^-\rightarrow D_s^-D^0$ has been calculated under the factorization approach. This decay mode includes current-current tree and penguin diagrams and their amplitudes are considered separately. In each of the tree and penguin amplitudes, the strong and weak phases have been introduced. The $CP$ asymmetry has been calculated in this work to be $(-0.35\pm0.03)\%$. Finally, from the sum of the amplitudes, we have calculated the total amplitude and obtained comparable results with experimental value for the branching ratio of $B^-\rightarrow D_s^-D^0$ decay.

hep-ph↗