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.

First determination of the spin and parity of the charmed-strange baryon Xi(c) (2970)( )

Abstract: We report results from a study of the spin and parity of $\Xi_{c}(2970)^+$ using a $980~\mathrm{fb^{-1}}$ data sample collected by the Belle detector at the KEKB asymmetric-energy $e^{+}e^{-}$ collider. The decay angle distributions in the chain $\Xi_{c}(2970)^+ \to \Xi_c(2645)^{0}\pi^{+} \to \Xi_c^{+}\pi^{-}\pi^{+}$ are analyzed to determine the spin of this charmed-strange baryon. The angular distributions strongly favor the $\Xi_{c}(2970)^+$ spin $J =1/2$ over $3/2$ or $5/2$, under an assumption that the lowest partial wave dominates in the decay. We also measure the ratio of $\Xi_{c}(2970)^+$ decay branching fractions $R={\mathcal{B}[ \Xi_{c}(2970)^+ \to \Xi_c(2645)^{0}\pi^{+} ]} / { \mathcal{B}[ \Xi_{c}(2970)^+ \to \Xi_c^{\prime0}\pi^{+} ]} =1.67 \pm 0.29\mathrm{(stat.)}^{ +0.15}_{ -0.09}\mathrm{(syst.)} \pm 0.25\mathrm{(IS)}$, where the last uncertainty is due to possible isospin-symmetry-breaking effects. This $R$ value favors the spin-parity $J^P=1/2^+$ with the spin of the light-quark degrees of freedom $s_{l}=0$. This is the first determination of the spin and parity of a charmed-strange baryon.

Completely-arbitrary passage retrieval in language modeling approach

Abstract: Passage retrieval has been expected to be an alternative method to re-solve length-normalization problem, since passages have more uniform lengths and topics, than documents. An important issue in the passage retrieval is to determine the type of the passage. Among several different passage types, the arbitrary passage type which dynamically varies according to query has shown the best performance. However, the previous arbitrary passage type is not fully examined, since it still uses the fixed-length restriction such as n consequent words. This paper proposes a new type of passage, namely completely-arbitrary passages by eliminating all possible restrictions of passage on both lengths and starting positions, and by extremely relaxing the type of the original arbitrary passage. The main advantage using completely-arbitrary passages is that the proximity feature of query terms can be well-supported in the passage retrieval, while the non-completely arbitrary passage cannot clearly support. Experimental result extensively shows that the passage retrieval using the completely-arbitrary passage significantly improves the document retrieval, as well as the passage retrieval using previous non-completely arbitrary passages, on six standard TREC test collections, in the context of language modeling approaches.

Inclusive cross sections for pairs of identified light charged hadrons and for single protons in e + e − at s = 10.58 GeV

Abstract: We report the first double differential cross sections of two charged pions and kaons (e(+)e(-) -> hhX) in electron-positron annihilation as a function of the fractional energies of the two hadrons for any charge and hadron combination. The dependence of these dihadron cross sections on the topology (same, opposite hemisphere or anywhere) is also studied with the help of the event shape variable thrust and its axis. The ratios of these dihadron cross sections for different charges and hadron combinations directly shed light on the contributing fragmentation functions. For example, we find that the ratio of same-sign pion pairs over opposite-sign pion pairs drops toward higher fractional energies where disfavored fragmentation is expected to be suppressed. These dihadron results are obtained from a 655 fb(-1) data sample collected near the gamma (4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. Extending the previously published single-pion and single-kaon cross sections, single-proton (e(+)e(-) -> pX) cross sections are extracted from a 159 fb(-1) data subsample.

Event-shape and multiplicity dependence of freeze-out radii in pp collisions at √s = 7 TeV

Abstract: Two-particle correlations in high-energy collision experiments enable the extraction of particle source radii by using the Bose-Einstein enhancement of pion production at low relative momentum q ∝ 1/R. It was previously observed that in pp collisions at $ \sqrt{s} $ = 7TeV the average pair transverse momentum k$_{T}$ range of such analyses is limited due to large background correlations which were attributed to mini-jet phenomena. To investigate this further, an event-shape dependent analysis of Bose-Einstein correlations for pion pairs is performed in this work. By categorizing the events by their transverse sphericity S$_{T}$ into spherical (S$_{T}$ > 0:7) and jet-like (S$_{T}$ < 0:3) events a method was developed that allows for the determination of source radii for much larger values of k$_{T}$ for the first time. Spherical events demonstrate little or no background correlations while jet-like events are dominated by them. This observation agrees with the hypothesis of a mini-jet origin of the non-femtoscopic background correlations and gives new insight into the physics interpretation of the k$_{T}$ dependence of the radii. The emission source size in spherical events shows a substantially diminished k$_{T}$ dependence, while jet-like events show indications of a negative trend with respect to k$_{T}$ in the highest multiplicity events. Regarding the emission source shape, the correlation functions for both event sphericity classes show good agreement with an exponential shape, rather than a Gaussian one.

Polyselenide Anchoring Using Transition-Metal Disulfides for Enhanced Lithium-Selenium Batteries.

Abstract: While selenium has recently been proposed as a lithium battery cathode as a promising alternative to a lithium–sulfur battery, dissolution of intermediate species should be resolved to improve its cycle stability. Here, we report the promising results of transition-metal disulfides as an anchoring material and the underlying origin for preventing active material loss from the electrode using density functional theory calculations. Group 5 and 4 disulfides (VS2, NbS2, TaS2, TiS2, ZrS2, and HfS2) in particular show anchoring capabilities superior to those of group 6 disulfides (CrS2, MoS2, and WS2). The governing interaction controlling the latter relative anchoring strengths is shown to be charge transfer as understood by crystal-field theory. The current findings and methodologies provide novel chemical insight for the further design of inorganic anchoring materials for both lithium–selenium and lithium–sulfur batteries.