We study the spectrum and rearrangement decays of S-wave cscˉsˉ
tetraquark states in a simplified quark model. The masses and widths are
estimated by assuming that the X(4140) is the lower 1++cscˉsˉ tetraquark. Comparing our results with experimental
measurements, we find that the recently observed X(3960) by LHCb can be
assigned as the lowest 0++cscˉsˉ tetraquark state and the
X0​(4140) could be the second lowest 0++cscˉsˉ tetraquark.
Predictions of ratios between partial widths for the involved tetraquarks are
given. We call for searches for more cscˉsˉ tetraquarks with
JPC=1+−, 0++, and 2++