Korea Institute of Science and Technology Information

About: Korea Institute of Science and Technology Information is a facility organization based out in Daejeon, South Korea. It is known for research contribution in the topics: Gravitational wave & LIGO. The organization has 1152 authors who have published 2319 publications receiving 93849 citations. The organization is also known as: Korea Institute of Science and Technology Information & KISTI.

Simplicity is Better: Revisiting Single Kernel PPI Extraction

Abstract: It has been known that a combination of multiple kernels and addition of various resources are the best options for improving effectiveness of kernel-based PPI extraction methods. These supplements, however, involve extensive kernel adaptation and feature selection processes, which attenuate the original benefits of the kernel methods. This paper shows that we are able to achieve the best performance among the state-of-the-art methods by using only a single kernel, convolution parse tree kernel. In-depth analyses of the kernel reveal that the keys to the improvement are the tree pruning method and consideration of tree kernel decay factors. It is noteworthy that we obtained the performance without having to use any additional features, kernels or corpora.

Observation of Ξ c(2930) 0 and updated measurement of B-→K-Λc+Λ¯c- at Belle: Belle Collaboration

Abstract: We report the first observation of the $$\Xi _{c}(2930)^0$$ charmed-strange baryon with a significance greater than 5 $$\sigma $$ . The $$\Xi _{c}(2930)^0$$ is found in its decay to $$K^- \Lambda _{c}^+$$ in $$B^{-} \rightarrow K^{-} \Lambda _{c}^{+} \bar{\Lambda }_{c}^{-}$$ decays. The measured mass and width are $$[2928.9 \pm 3.0(\mathrm stat.)^{+0.9}_{-12.0}(\mathrm syst.)]$$ MeV/ $$c^{2}$$ and $$[19.5 \pm 8.4(\mathrm stat.) ^{+5.9}_{-7.9}(\mathrm syst.)]$$ MeV, respectively, and the product branching fraction is $$\mathcal{B}(B^{-} \rightarrow \Xi _{c}(2930)^0 \bar{\Lambda }_{c}^{-}) \mathcal{B}(\Xi _{c}(2930)^0 \rightarrow K^- \Lambda _{c}^{+})=[1.73 \pm 0.45(\mathrm stat.) \pm 0.21(\mathrm syst.)]\times 10^{-4}$$ . We also measure $$\mathcal{B}(B^{-} \rightarrow K^{-} \Lambda _{c}^{+} \bar{\Lambda }_{c}^{-}) = [4.80 \pm 0.43(\mathrm stat.) \pm 0.60(\mathrm syst.)] \times 10^{-4}$$ with improved precision, and search for the charmonium-like state Y(4660) and its spin partner, $$Y_{\eta }$$ , in the $$\Lambda _{c}^{+}\bar{\Lambda }_{c}^{-}$$ invariant mass spectrum. No clear signals of the Y(4660) nor its spin partner are observed and the 90% credibility level (C.L.) upper limits on their production rates are determined. These measurements are obtained from a sample of $$(772\pm 11)\times 10^{6} B\bar{B}$$ pairs collected at the $$\Upsilon (4S)$$ resonance by the Belle detector at the KEKB asymmetric energy electron–positron collider.

Measurement of beauty and charm production in pp collisions at $$ \sqrt{s} $$ = 5.02 TeV via non-prompt and prompt D mesons

Abstract: The pT-differential production cross sections of prompt and non-prompt (produced in beauty-hadron decays) D mesons were measured by the ALICE experiment at midrapidity (|y| < 0.5) in proton-proton collisions at $$ \sqrt{s} $$ = 5.02 TeV. The data sample used in the analysis corresponds to an integrated luminosity of (19.3 ± 0.4) nb−1. D mesons were reconstructed from their decays D0 → K−π+, D+ → K−π+π+, and $$ {\mathrm{D}}_{\mathrm{s}}^{+}\to \upphi {\uppi}^{+}\to {\mathrm{K}}^{-}{\mathrm{K}}^{+}{\uppi}^{+} $$ and their charge conjugates. Compared to previous measurements in the same rapidity region, the cross sections of prompt D+ and $$ {\mathrm{D}}_{\mathrm{s}}^{+} $$ mesons have an extended pT coverage and total uncertainties reduced by a factor ranging from 1.05 to 1.6, depending on pT, allowing for a more precise determination of their pT-integrated cross sections. The results are well described by perturbative QCD calculations. The fragmentation fraction of heavy quarks to strange mesons divided by the one to non-strange mesons, fs/(fu + fd), is compatible for charm and beauty quarks and with previous measurements at different centre-of-mass energies and collision systems. The $$ \mathrm{b}\overline{\mathrm{b}} $$ production cross section per rapidity unit at midrapidity, estimated from non-prompt D-meson measurements, is $$ \mathrm{d}{\sigma}_{\mathrm{b}\overline{\mathrm{b}}}/\mathrm{d}y\left|{}_{\left|\mathrm{y}\right|<0.5}=34.5\pm 2.4{\left(\mathrm{stat}\right)}_{-2.9}^{+4.7}\left(\mathrm{tot}.\mathrm{syst}\right)\right. $$ μb. It is compatible with previous measurements at the same centre-of-mass energy and with the cross section pre- dicted by perturbative QCD calculations.