6,280 research outputs found
A Comprehensive Four-Quark Interpretation of D_s(2317), D_s(2457) and D_s(2632)
The recently observed new member of the charm-strange family D_s(2632) which
has a surprisingly narrow width is challenging our theory. D_s(2317) and
D_s(2457) which were observed earlier have similar behaviors and receive
various theoretical explanations. Some authors use the heavy hadron chiral
effective theory to evaluate heavy-light quark systems and obtain a reasonable
evaluation on the masses of D_s(2317) and D_s(2457). An alternative picture is
to interpret them as four-quark or molecular states. In this work, we are
following the later and propose a unitive description for all the three new
members D_s(2632), D_s(2317) and D_s(2457) and at least, so far our picture is
consistent with the data.Comment: 6 page
(3,6-Dibromo-o-phenylÂene)dimethanol
The title compound, C8H8Br2O2, was synthesized from the hydrolysis of 1,4-dibromo-2,3-bisÂ(bromoÂmethÂyl)benzene. One intraÂmolecular O—H⋯O and two intraÂmolecular C—H⋯Br interÂactions occur. In the crystal, molÂecules are linked into a chain running parallel to [010]. Adjacent chains are linked into a two-dimensional layer by a combination of interÂmolecular O—H⋯O hydrogen bonds and C—H⋯π interÂactions
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