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The recently discovered kagome superconductorsAV₃Sb₅(A= K, Rb, Cs) exhibit unusual charge-density-wave (CDW) orders with time-reversal and rotational symmetry breaking. One of the most crucial unresolved issues is identifying the symmetry of the superconductivity that develops inside the CDW phase. Theory predicts a variety of unconventional superconducting symmetries with sign-changing and chiral order parameters. Experimentally, however, superconducting phase information inAV₃Sb₅is still lacking. Here we report the impurity effects in CsV₃Sb₅using electron irradiation as a phase-sensitive probe of superconductivity. Our magnetic penetration depth measurements reveal that with increasing impurities, an anisotropic fully-gapped state changes to an isotropic full-gap state without passing through a nodal state. Furthermore, transport measurements under pressure show that the double superconducting dome in the pressure-temperature phase diagram survives against sufficient impurities. These results support that CsV₃Sb₅is a non-chiral, anisotropics-wave superconductor with no sign change both at ambient and under pressure.

 

Echinoderms are an exceptional group of bilaterians that develop pentameral adult symmetry from a bilaterally symmetric larva. However, the genetic basis in evolution and development of this unique transformation remains to be clarified. Here we report newly sequenced genomes, developmental transcriptomes, and proteomes of diverse echinoderms including the green sea urchin (L. variegatus), a sea cucumber (A. japonicus), and with particular emphasis on a sister group of the earliest-diverged echinoderms, the feather star (A. japonica). We learned that the last common ancestor of echinoderms retained a well-organized Hox cluster reminiscent of the hemichordate, and had gene sets involved in endoskeleton development. Further, unlike in other animal groups, the most conserved developmental stages were not at the body plan establishing phase, and genes normally involved in bilaterality appear to function in pentameric axis development. These results enhance our understanding of the divergence of protostomes and deuterostomes almost 500 Mya. 

We report the first measurement of the inclusivee⁺e⁻→$$ b\overline{b} $$$b\overline{b}$→$$ {D}_s^{\pm } $$$D_s^{\pm }$Xande⁺e⁻→$$ b\overline{b} $$$b\overline{b}$→ D⁰/$$ {\overline{D}}^0 $$${\overline{D}}^0$Xcross sections in the energy range from 10.63 to 11.02 GeV. Based on these results, we determineσ(e⁺e⁻→$$ {B}_s^0{\overline{B}}_s^0 $$$B_s^0{\overline{B}}_s^0$X) andσ(e⁺e⁻→$$ B\overline{B} $$$B\overline{B}$X) in the same energy range. We measure the fraction of$$ {B}_s^0 $$$B_s^0$events at Υ(10860) to bef_s= ($$ {22.0}_{-2.1}^{+2.0} $$${22.0}_{-2.1}^{+2.0}$)%. We determine also the ratio of the$$ {B}_s^0 $$$B_s^0$inclusive branching fractions$$ \mathcal{B} $$$B$($$ {B}_s^0 $$$B_s^0$→ D⁰/$$ {\overline{D}}^0 $$${\overline{D}}^0$X)/$$ \mathcal{B} $$$B$($$ {B}_s^0 $$$B_s^0$→$$ {D}_s^{\pm } $$$D_s^{\pm }$X) = 0.416 ± 0.018 ± 0.092. The results are obtained using the data collected with the Belle detector at the KEKB asymmetric-energye⁺e⁻collider.