The $\bar{B}^0 \to D^{*+} \bar{D}^{*0} K^- $ reaction to detect the $I=0, J^P=1^+$ partner of the $X_0(2866)$

Abstract

We have chosen the B0 → D * + D * 0 K − reaction in order to observe the I = 0, J P = 1 + (R1) partner state of the X0(2866) stemming from the D * K * molecular picture. The reaction proceeds via external emission in the most favored Cabibbo decay mode and one observes the R1 state as a very strong peak versus the background in the D * + K − spectrum. The branching ratio for R1 production in this reaction is estimated of the order of 4 × 10 −3 . The method used, applied to the B + → D − D + K + reaction, produces a ratio of signal to background in the D − K + spectrum in very good agreement with the LHCb experiment that observed the X0(2866).

Looking for the exotic $X_0(2866)$ and its $J^P=1^+$ partner in the $\bar{B}^0 \to D^{(*)+} K^- K^{(*)0} $ reactions

“…3. We can see a peak clearly sticking out of the background, as was also found in [43] with a different reaction. It is clear that even if there were uncertainties of a factor of two or three, the signal should be clearly seen.…”

“…4. We also see a signal that sticks out of the background clearly, as was shown in [43] for the B − → D + D − K − reaction in the production of the X 0 (2866). As this point we would like to make some discussion.…”

“…The K ( * )0 in the Belle reactions would play the role of the D − in the LHCb one. The study is stimulated by the success found in [43], fairly reproducing the D K peak versus the background of [19] in the study of the B − → D + D − K − reaction. This success was used in [43] to suggest the B0 → D * + D * 0 K − decay in order to investigate the 1 + state of Table I by looking at the D * + K − mass distribution.…”

“…The study is stimulated by the success found in [43], fairly reproducing the D K peak versus the background of [19] in the study of the B − → D + D − K − reaction. This success was used in [43] to suggest the B0 → D * + D * 0 K − decay in order to investigate the 1 + state of Table I by looking at the D * + K − mass distribution. It was found that the 1 + state generated a peak in the distribution with a strength about 7 times bigger than the background at the peak of the 1 + contribution.…”