The new members of the charm-strange family Dsj^＊（2317）, Dsj（2460）, and Ds（2632）, which have the surprising properties, are challenging the present models. Many theoretical interpretations have been devoted to ...The new members of the charm-strange family Dsj^＊（2317）, Dsj（2460）, and Ds（2632）, which have the surprising properties, are challenging the present models. Many theoretical interpretations have been devoted to this issue. Most authors suggest that they are not the conventional cs^- quark model states, but possibly are four-quark states, molecule states, or mixtures of a P-wave cs^- and a four-quark state. In this work, we follow the four-quark-state picture, and study the masses of cnn^-s^-/css^-s^- states （n is u or d quark） in the chiral SU（3） quark model. The numerical results show that the mass of the mixed four-quark state （cnn^-s^-/css^-s^-） with spin parity j^P ： 0^＋ might not be Ds （2632）. At the same time, we also conclude that Dsj^＊（2317） and Dsj（2460） cannot be explained as the pure four-quark state.展开更多
The widths for pionic decays of the lowest two excited doublets(0^(+),1^(+))and(1^(+),2^(+))of heavy mesons are studied with quantum Chromodynamics sum rules in the heavy quark effective theory.The interpolating curre...The widths for pionic decays of the lowest two excited doublets(0^(+),1^(+))and(1^(+),2^(+))of heavy mesons are studied with quantum Chromodynamics sum rules in the heavy quark effective theory.The interpolating currents used allow us to distinguish the two 1^(+)states without contamination in the infinite mass limit.The soft pion approximation is not used in the calculations.展开更多
基金National Natural Science Foundation of China under Grant No 10475087
文摘The new members of the charm-strange family Dsj^＊（2317）, Dsj（2460）, and Ds（2632）, which have the surprising properties, are challenging the present models. Many theoretical interpretations have been devoted to this issue. Most authors suggest that they are not the conventional cs^- quark model states, but possibly are four-quark states, molecule states, or mixtures of a P-wave cs^- and a four-quark state. In this work, we follow the four-quark-state picture, and study the masses of cnn^-s^-/css^-s^- states （n is u or d quark） in the chiral SU（3） quark model. The numerical results show that the mass of the mixed four-quark state （cnn^-s^-/css^-s^-） with spin parity j^P ： 0^＋ might not be Ds （2632）. At the same time, we also conclude that Dsj^＊（2317） and Dsj（2460） cannot be explained as the pure four-quark state.
基金Supported by the National Natural Science Foundation of China under Grant No.19335043.
文摘The widths for pionic decays of the lowest two excited doublets(0^(+),1^(+))and(1^(+),2^(+))of heavy mesons are studied with quantum Chromodynamics sum rules in the heavy quark effective theory.The interpolating currents used allow us to distinguish the two 1^(+)states without contamination in the infinite mass limit.The soft pion approximation is not used in the calculations.
