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.

Parameter estimation of gravitational waves from nonprecessing black hole-neutron star inspirals with higher harmonics: Comparing Markov-chain Monte Carlo posteriors to an effective Fisher matrix

Abstract: Most calculations of the gravitational wave signal from merging compact binaries limit attention to the leading-order quadrupole when constructing models for detection or parameter estimation. Some studies have claimed that if additional ``higher harmonics'' are included consistently in the gravitational wave signal and search model, binary parameters can be measured much more precisely. Using the lalinference Markov-chain Monte Carlo parameter estimation code, we construct posterior parameter constraints associated with two distinct nonprecessing black hole--neutron star (BH-NS) binaries, each with and without higher-order harmonics. All simulations place a plausible signal into a three-detector network with Gaussian noise. Our simulations suggest that higher harmonics provide little information, principally allowing us to measure a previously unconstrained angle associated with the source geometry well but otherwise improving knowledge of all other parameters by a few percent for our loud fiducial signal ($\ensuremath{\rho}=20$). Even at this optimistic signal amplitude, different noise realizations have a more significant impact on parameter accuracy than higher harmonics. We compare our results with the ``effective Fisher matrix'' introduced previously as a method to obtain robust analytic predictions for complicated signals with multiple significant harmonics. We find generally good agreement with these predictions, confirm that intrinsic parameter measurement accuracy is nearly independent of detector network geometry, and show that uncertainties in extrinsic and intrinsic parameters can, to a good approximation, be separated. For our fiducial example, the individual masses can be determined to lie between $7.11--11.48{M}_{\ensuremath{\bigodot}}$ and $1.77--1.276{M}_{\ensuremath{\bigodot}}$ at greater than 99% confidence level, accounting for unknown BH spin. Assuming comparable control over waveform systematics, measurements of BH-NS binaries can constrain the BH and perhaps NS mass distributions. Using analytic arguments to guide extrapolation, we anticipate that higher harmonics should provide little new information about nonprecessing BH-NS binaries, for the signal amplitudes expected for the first few detections. Though our study focused on one particular example---higher harmomics---any study of subdominant degrees of freedom in gravitational wave astronomy can adopt the tools presented here ($V/{V}_{\text{prior}}$ and ${D}_{\mathrm{KL}}$) to assess whether new physics is accessible (e.g., modifications of gravity, spin-orbit misalignment) and if so precisely what information those new parameters provide.

Surface model of the gastrointestinal tract constructed from the Visible Korean

Abstract: Most currently available three-dimensional surface models of human anatomic structures have been artistically created to reflect the anatomy being portrayed. We have recently undertaken, as part of our Visible Korean studies, to build objective surface models based on cross-sectional images of actual human anatomy. Objective of the present study was to elaborate surface models of the GI tract and neighboring structures that are helpful to medical simulation. The GI tract from stomach to anal canal was outlined and reconstructed from sectioned images of the Visible Korean (a computer database containing the digitized transverse sectional images of a 33-year-old Korean man). The outlining procedure was supported by computational filtering and interpolation using commercially available software. The GI tract was divided into several parts, and each of these parts was surface reconstructed and then united with neighboring parts to produce a surface model of the complete GI tract. Surface models of about 100 neighboring structures were also prepared. The surface models produced will hopefully facilitate the development of interactive simulations for a variety of virtual abdominal surgical procedures or other educational programs. In addition, it is hoped that the improved outlining and surface reconstruction techniques described will encourage other researchers to construct similar surface models based on images obtained from different subjects. Clin. Anat. 22:601–609, 2009. V C 2009 Wiley-Liss, Inc.

Muon detector for the COSINE-100 experiment

Abstract: The COSINE-100 dark matter search experiment has started taking physics data with the goal of performing an independent measurement of the annual modulation signal observed by DAMA/LIBRA. A muon detector was constructed by using plastic scintillator panels in the outermost layer of the shield surrounding the COSINE-100 detector. It detects cosmic ray muons in order to understand the impact of the muon annual modulation on dark matter analysis. Assembly and initial performance tests of each module have been performed at a ground laboratory. The installation of the detector in the Yangyang Underground Laboratory (Y2L) was completed in the summer of 2016. Using three months of data, the muon underground flux was measured to be 328 ± 1(stat.)± 10(syst.) muons/m2/day. In this report, the assembly of the muon detector and the results from the analysis are presented.

Neutral pion and η meson production in p–Pb collisions at √sNN = 5.02 TeV

Abstract: Neutral pion and $\eta $ meson invariant differential yields were measured in non-single diffractive p–Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 502 TeV with the ALICE experiment at the CERN LHC The analysis combines results from three complementary photon measurements, utilizing the PHOS and EMCal calorimeters and the Photon Conversion Method The invariant differential yields of $\pi ^{0}$ and $\eta $ meson inclusive production are measured near mid-rapidity in a broad transverse momentum range of $03 4 $\hbox {GeV}/c$ at $0483 \pm 0015_{\mathrm{stat}} \pm 0015_{\mathrm{sys}}$ A deviation from $m_{\mathrm{T}}$ scaling is observed for $p_{\mathrm{T}}<$ 2 $\hbox {GeV}/c$ The measured $\eta /\pi ^{0}$ ratio is consistent with previous measurements from proton-nucleus and pp collisions over the full $p_{\mathrm{T}}$ range The measured $\eta /\pi ^{0}$ ratio at high $p_{\mathrm{T}}$ also agrees within uncertainties with measurements from nucleus–nucleus collisions The $\pi ^{0}$ and $\eta $ yields in p–Pb relative to the scaled pp interpolated reference, $R_{{\mathrm{pPb}}}$ , are presented for $03 < p_{\mathrm{T}}<$ 20 $\hbox {GeV}/c$ and $07 < p_{\mathrm{T}}<$ 20 $\hbox {GeV}/c$ , respectively The results are compared with theoretical model calculations The values of $R_{{\mathrm{pPb}}}$ are consistent with unity for transverse momenta above 2 $\hbox {GeV}/c$ These results support the interpretation that the suppressed yield of neutral mesons measured in Pb–Pb collisions at LHC energies is due to parton energy loss in the hot QCD medium