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$D_{sJ}^+(2632)$: An Excellent Candidate of Tetraquarks

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 نشر من قبل Shi-Lin Zhu
 تاريخ النشر 2004
  مجال البحث
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We analyze various possible interpretations of the narrow state $D_{sJ}(2632)$ which lies 100 MeV above threshold. This interesting state decays mainly into $D_s eta$ instead of $D^0 K^+$. If this relative branching ratio is further confirmed by other experimental groups, we point out that the identification of $D_{sJ}(2632)$ either as a $cbar s$ state or more generally as a ${bf {bar 3}}$ state in the $SU(3)_F$ representation is probably problematic. Instead, such an anomalous decay pattern strongly indicates $D_{sJ}(2632)$ is a four quark state in the $SU(3)_F$ ${bf 15}$ representation with the quark content ${1over 2sqrt{2}} (dsbar{d}+sdbar{d}+subar{u}+usbar{u}-2ssbar{s})bar{c}$. We discuss its partners in the same multiplet, and the similar four-quark states composed of a bottom quark $B_{sJ}^0(5832)$. Experimental searches of other members especially those exotic ones are strongly called for.



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We analyze various possible interpretations of the narrow state $D_{sJ}^+(2632)$ observed by SELEX Collaboration recently, which lies above threshold and has abnormal decay pattern. These interpretations include: (1) sever
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