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decays with the Belle II experimentAbudin
n, F.*; 谷田 聖; Belle II Collaboration*; 他413名*
Physical Review D, 107(7), p.072002_1 - 072002_24, 2023/04
被引用回数：14 パーセンタイル：78.14(Astronomy & Astrophysics)We present measurements of the first to fourth moments of the lepton mass squared 
of 
decays for 
and with 
a hadronic system containing a charm quark. These results use a sample of electron-positron collisions at the 
resonance corresponding to 
of integrated luminosity and collected by the Belle II experiment in 2019 and 2020. To identify the system and reconstruct , one of the 
mesons from an 
decay is fully reconstructed in a hadronic decay mode using a multivariate tagging algorithm. We report raw and central moments for 
up to 
, probing up to 77% of the accessible phase space. This is the first measurement of moments in the experimentally challenging range of ![$$[ 1.5, 2.5 ] , mathrm{GeV^2/c^4}$$](/search/images/ERNSAMJOGUWCAMROGUQF0IC2FQQFY1LBORUHE1L1I3SVMXRSF3RV2ND3EQ.gif)
.
lifetime at Belle IIAbudinn, F.*; 谷田 聖; Belle II Collaboration*; 他354名*
Physical Review D, 107(3), p.L031103_1 - L031103_7, 2023/02
被引用回数：6 パーセンタイル：53.22(Astronomy & Astrophysics)We report on a measurement of the lifetime using 
decays reconstructed in 
data collected by the Belle II experiment and corresponding to 
of integrated luminosity. The result, 
, agrees with recent measurements indicating that the is not the shortest-lived weakly decaying charmed baryon.
and missing energy final states with the Belle II experimentAbudinn, F.*; 谷田 聖; Belle II Collaboration*; 他355名*
Physical Review Letters, 130(7), p.071804_1 - 071804_8, 2023/02
被引用回数：10 パーセンタイル：73.47(Physics, Multidisciplinary)The dark photon 
and the dark Higgs boson 
are hypothetical particles predicted in many dark sector models. We search for the simultaneous production of and in the dark Higgsstrahlung process 
with 
and 
invisible in electron-positron collisions at a center-of-mass energy of 10.58 GeV collected by the Belle II experiment in 2019. With an integrated luminosity of 8.34 fb
, we observe no evidence for signal. We obtain exclusion limits at 90% Bayesian credibility in the range of 1.7-5.0 fb on the cross section and in the range of 
-
on the effective coupling 
for the mass in the range of 4.0 GeV/
GeV/ and for the mass 
, where 
is the mixing strength between the standard model and the dark photon and 
is the coupling of the dark photon to the dark Higgs boson. Our limits are the first in this mass range.
using 
decaysAbudinn, F.*; 谷田 聖; Belle II Collaboration*; 他319名*
Journal of High Energy Physics (Internet), 2022(2), p.63_1 - 63_33, 2022/02
被引用回数：9 パーセンタイル：55.55(Physics, Particles & Fields)We present a measurement of the Cabibbo-Kobayashi-Maskawa unitarity triangle angle (also known as~
) using a model-independent Dalitz plot analysis of 
, where 
is either a 
or 
meson and 
is either a 
or 
. This is the first measurement that simultaneously uses Belle and Belle~II data, combining samples corresponding to integrated luminosities of 711 fb and 128 fb, respectively. All data were accumulated from energy-asymmetric 
collisions at a centre-of-mass energy corresponding to the mass of the resonance. We measure 
, where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is from the uncertainties on external measurements of the -decay strong-phase parameters.
and 
lifetimes at Belle IIAbudinn, F.*; 谷田 聖; Belle II Collaboration*; 他385名*
Physical Review Letters, 127(21), p.211801_1 - 211801_9, 2021/11
被引用回数：14 パーセンタイル：67.39(Physics, Multidisciplinary)We report a measurement of the and lifetimes using 
and 
decays reconstructed in data recorded by the Belle II experiment at the SuperKEKB asymmetric-energy collider. The data, collected at center-of-mass energies at or near the resonance, correspond to an integrated luminosity of 
. The results, 
and 
, are the most precise to date and are consistent with previous determinations.
collisions at Belle IIAbudinn, F.*; 谷田 聖; Belle II Collaboration*; 他334名*
Physical Review Letters, 125(16), p.161806_1 - 161806_9, 2020/10
被引用回数：61 パーセンタイル：92.82(Physics, Multidisciplinary)We present a search for the direct production of a light pseudoscalar 
decaying into two photons with the Belle II detector at the SuperKEKB collider. We search for the process 
in the mass range 
using data corresponding to an integrated luminosity of 
pb. Light pseudoscalars interacting predominantly with standard model gauge bosons (so-called axion-like particles or ALPs) are frequently postulated in extensions of the standard model. We find no evidence for ALPs and set 95% confidence level upper limits on the coupling strength 
of ALPs to photons at the level of 
GeV. The limits are the most restrictive to date for 
GeV/.
boson at Belle II in 
plus missing energy final states足立 一郎*; 谷田 聖; Belle II Collaboration*; 他358名*
Physical Review Letters, 124(14), p.141801_1 - 141801_9, 2020/04
被引用回数：65 パーセンタイル：93.30(Physics, Multidisciplinary)Theories beyond the standard model often predict the existence of an additional neutral boson, the . Using data collected by the Belle II experiment during 2018 at the SuperKEKB collider, we perform the first searches for the invisible decay of a in the process 
and of a lepton-flavor-violating in 
. We do not find any excess of events and set 90% credibility level upper limits on the cross sections of these processes. We translate the former, in the framework of an 
theory, into upper limits on the coupling constant at the level of 
- 
for 
GeV/.
Abudinn, F.*; 谷田 聖; Belle II Collaboration*; 他420名*
Chinese Physics C, 44(2), p.021001_1 - 021001_12, 2020/02
被引用回数：34 パーセンタイル：93.05(Physics, Nuclear)From April to July 2018, a data sample at the peak energy of the resonance was collected with the Belle II detector at the SuperKEKB electron-positron collider. This is the first data sample of the Belle II experiment. Using Bhabha and digamma events, we measure the integrated luminosity of the data sample to be (
) pb, where the first uncertainty is statistical and the second is systematic. This work provides a basis for future luminosity measurements at Belle II.
Kou, E.*; 谷田 聖; Belle II Collaboration*; 他537名*
Progress of Theoretical and Experimental Physics (Internet), 2020(2), p.029201_1 - 029201_6, 2020/02
被引用回数：153 パーセンタイル：99.68(Physics, Multidisciplinary)In the original version of this manuscript, an error was introduced on pp.352. "2.7nb:1.6nb" has been corrected to "2.4nb:1.3nb" in the current online and printed version.
Kou, E.*; 谷田 聖; Belle II Collaboration*; 他537名*
Progress of Theoretical and Experimental Physics (Internet), 2019(12), p.123C01_1 - 123C01_654, 2019/12
被引用回数：599 パーセンタイル：99.95(Physics, Multidisciplinary)We present the physics program of the Belle II experiment, located on the intensity frontier SuperKEKB collider. Belle II collected its first collisions in 2018, and is expected to operate for the next decade. It is anticipated to collect 50/ab of collision data over its lifetime. This book is the outcome of a joint effort of Belle II collaborators and theorists through the Belle II theory interface platform (B2TiP), an effort that commenced in 2014. The aim of B2TiP was to elucidate the potential impacts of the Belle II program, which includes a wide scope of physics topics: B physics, charm, tau, quarkonium, electroweak precision measurements and dark sector searches. It is composed of nine working groups (WGs), which are coordinated by teams of theorist and experimentalists conveners: Semileptonic and leptonic B decays, Radiative and Electroweak penguins, 
and 
(time-dependent CP violation) measurements, 
measurements, Charmless hadronic B decay, Charm, Quarkonium(-like), tau and low-multiplicity processes, new physics and global fit analyses. This book highlights "golden- and silver-channels", i.e. those that would have the highest potential impact in the field. Theorists scrutinised the role of those measurements and estimated the respective theoretical uncertainties, achievable now as well as prospects for the future. Experimentalists investigated the expected improvements with the large dataset expected from Belle II, taking into account improved performance from the upgraded detector.
Adamczyk, K.*; 谷田 聖; Belle-II SVD Collaboration*; 他97名*
Nuclear Instruments and Methods in Physics Research A, 845, p.38 - 42, 2017/02
被引用回数：3 パーセンタイル：23.81(Instruments & Instrumentation)The Belle II experiment at the asymmetric SuperKEKB collider in Japan will operate at an instantaneous luminosity approximately 50 times greater than its predecessor (Belle). The central feature of the experiment is a vertex detector comprising two layers of pixelated silicon detectors (PXD) and four layers of double-sided silicon microstrip detectors (SVD). One of the key measurements for Belle II is CP violation asymmetry in the decays of beauty and charm hadrons, which hinges on a precise charged-track vertex determination and low-momentum track measurement. Towards this goal, a proper assembly of the SVD components with precise alignment ought to be performed and the geometrical tolerances should be checked to fall within the design limits. We present an overview of the assembly procedure that is being followed, which includes the precision gluing of the SVD module components, wire-bonding of the various electrical components, and precision 3D coordinate measurements of the final SVD modules.
Kang, K. H.*; 谷田 聖; Belle-II SVD Collaboration*; 他94名*
Nuclear Instruments and Methods in Physics Research A, 831, p.213 - 220, 2016/09
被引用回数：0 パーセンタイル：0.00(Instruments & Instrumentation)A silicon vertex detector (SVD) for the Belle-II experiment comprises four layers of double-sided silicon strip detectors (DSSDs), assembled in a ladder-like structure. Each ladder module of the outermost SVD layer has four rectangular and one trapezoidal DSSDs supported by two carbon-fiber ribs. In order to achieve a good signal-to-noise ratio and minimize material budget, a novel chip-on-sensor "Origami" method has been employed for the three rectangular sensors that are sandwiched between the backward rectangular and forward (slanted) trapezoidal sensors. This paper describes the bonding procedures developed for making electrical connections between sensors and signal fan-out flex circuits (i.e., pitch adapters), and between pitch adapters and readout chips as well as the results in terms of the achieved bonding quality and pull force.
