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Yang, S.*; 谷田 聖; Belle Collaboration*; 他196名*
Physical Review D, 108(3), p.L031104_1 - L031104_6, 2023/08
被引用回数:5 パーセンタイル:42.62(Astronomy & Astrophysics)We observe a narrow peaking structure in the invariant-mass spectrum near the
threshold. The peak is clearly seen in 1.5 million events of
decay using the
data sample collected by the Belle detector at the KEKB asymmetric-energy
collider. We try two approaches to explain this structure: as a new resonance and as a cusp at the
threshold. The best fit is obtained with a coherent sum of a Flatt
function and a constant background amplitude with the
(
), while the fits to Breit-Wigner functions are unfavored by more than 7
. The best fit explains the structure as a cusp at the
threshold, and the obtained parameters are consistent with the known properties of
. The observation gives the first identification of a threshold cusp in hadrons from the spectrum shape.
Yin, J. H.*; 谷田 聖; Belle Collaboration*; 他193名*
Physical Review D, 107(5), p.052004_1 - 052004_8, 2023/03
被引用回数:3 パーセンタイル:42.62(Astronomy & Astrophysics)We present a search for the decay in the
data sample collected at the Belle detector, where the
is produced in
and
decays. We do not observe a signal, and set 90% credible upper limits for two different models of the decay processes: if the decay products are distributed uniformly in phase space,
; if
is concentrated near the mass of the
pair in the process
,
.
Choudhury, S.*; 谷田 聖; Belle Collaboration*; 他198名*
Physical Review D, 107(3), p.L031102_1 - L031102_6, 2023/02
被引用回数:8 パーセンタイル:74.17(Astronomy & Astrophysics)We measure the ratio of branching fractions for the decays to
and
using
and
samples, where
stands for
(
or
), with
fb
of data collected at the
resonance with the Belle detector. We find the decay rate ratio of
over
to be
, which is the most precise measurement to date. The first and second uncertainties are statistical and systematic, respectively, and the third uncertainty is systematic due to the assumption of isospin symmetry in
.
Li, L. K.*; 谷田 聖; Belle Collaboration*; 他197名*
Physical Review D, 107(3), p.033003_1 - 033003_9, 2023/02
被引用回数:0 パーセンタイル:0.00(Astronomy & Astrophysics)We present measurements of the branching fractions for the singly Cabibbo-suppressed decays and
, and the doubly Cabibbo-suppressed decay
, based on 980
of data recorded by the Belle experiment at the KEKB
collider. We measure these modes relative to the Cabibbo-favored modes
and
. Our results for the ratios of branching fractions are
,
, and
, where the uncertainties are statistical and systematic, respectively. The second value corresponds to
, where
is the Cabibbo angle; this value is larger than other measured ratios of branching fractions for a doubly Cabibbo-suppressed charm decay to a Cabibbo-favored decay. Multiplying these results by world average values for
and
yields
,
, and
, where the third uncertainty is due to the branching fraction of the normalization mode. The first two results are consistent with, but more precise than, the current world averages. The last result is the first measurement of this branching fraction.
中村 智樹*; 大澤 崇人; 他219名*
Science, 379(6634), p.eabn8671_1 - eabn8671_14, 2023/02
被引用回数:208 パーセンタイル:99.97(Multidisciplinary Sciences)1から8mmのリュウグウ粒子16個の鉱物学的,岩石学的、および物理的特性は、それらがCIコンドライトに最も類似していることを示している。磁硫鉄鉱中のCO含有水の存在は、母天体が太陽系星雲のH
OおよびCO
のスノーラインを越えた領域で形成したことを示しており、ここでは、リュウグウの鉱物学に基づくと、小さなコンドリュールやCa, Alを含む非常に限られた量の高温物質がある。流体-岩石反応は、低温,高pH、および水/岩石の質量比が1未満の還元条件で発生し、リュウグウのサンプルで最も変化の少ない断片として残っているかんらん石-輝石に富む岩相を、リュウグウサンプルの主要な岩相であるフィロケイ酸塩-炭酸塩に富むものに変えた。リュウグウの母体の流体から磁鉄鉱が結晶化したとき、原始太陽系星雲はまだ存在していた可能性がある。
Krohn, J.-F.*; 谷田 聖; Belle Collaboration*; 他198名*
Physical Review D, 107(1), p.012003_1 - 012003_12, 2023/01
被引用回数:1 パーセンタイル:16.70(Astronomy & Astrophysics)Using
meson pairs recorded by the Belle experiment at the KEKB
collider, we report the branching fractions
and
; the quoted uncertainties are statistical and systematic, respectively. A measurement of the ratio of these branching fractions is also presented,
, where systematic uncertainties due to the
meson reconstruction cancel out. Furthermore, we report a new QCD factorization test based on the measured ratios for
and
decays at squared momentum transfer values equivalent to the mass of the
or
hadron. The parameters
are measured to be
and
, where the last uncertainties account for all external inputs. These values are approximately
lower than those expected from theoretical predictions. Subsequently, flavor
symmetry is tested by measuring the ratios for pions and kaons,
, as well as for different particle species. The ratio is consistent with unity and therefore no evidence for
symmetry breaking effects is found at the
precision level.
Li, Y. B.*; 谷田 聖; Belle Collaboration*; 他194名*
Physical Review Letters, 130(3), p.031901_1 - 031901_7, 2023/01
被引用回数:16 パーセンタイル:91.47(Physics, Multidisciplinary)We present the study of decays based on
events collected with the Belle detector at the KEKB asymmetric-energy
collider. The
candidates are reconstructed via their decay to
and
decays to
and
final states. The corresponding branching fractions are measured to be
and
, which are consistent with the world average values with improved precision. A new structure is found in the
spectrum with a significance of
including systematic uncertainty. The structure is possibly an excited
and is tentatively named
. Its mass and width are measured to be
MeV/
and
MeV, respectively. The products of branching fractions for the
are measured to be
and
. Here, the first and second uncertainties are statistical and systematic, respectively.
Jeon, H. B.*; 谷田 聖; Belle Collaboration*; 他219名*
Physical Review D, 106(1), p.012006_1 - 012006_9, 2022/07
被引用回数:0 パーセンタイル:0.00(Astronomy & Astrophysics)We report the first search for the penguin-dominated process using the full data sample of
pairs collected with the Belle detector at the KEKB asymmetric-energy
collider. We do not observe any statistically significant signal yield in the
-pair invariant mass range 1 GeV/
3 GeV/
, and set the following upper limits at 90% confidence level:
,
, and
. Further, 90% confidence upper limits have also been set in the range of [0.7-2.9]
on the
branching fraction in bins of
.
Li, S. X.*; 谷田 聖; Belle Collaboration*; 他197名*
Journal of High Energy Physics (Internet), 2022(3), p.90_1 - 90_11, 2022/03
被引用回数:8 パーセンタイル:55.29(Physics, Particles & Fields)We present the first measurement of the branching fraction of the singly Cabibbo-suppressed (SCS) decay with
, using a data sample corresponding to an integrated luminosity of 981
, collected by the Belle detector at the KEKB
asymmetric-energy collider. A significant
signal is observed for the first time with a signal significance of 5.4
. The relative branching fraction with respect to the normalization mode
is measured to be
,where the uncertainties are statistical and systematic, respectively. Using the world-average value of
, we obtain
,where the uncertainties are statistical, systematic, and from
, respectively.
Venhart, M.*; Andreyev, A. N.; Cubiss, J. G.*; Wood, J. L.*; Barzakh, A. E.*; Van Beveren, C.*; Cocolios, T. E.*; de Groote, R. P.*; 他19名*
Physical Review C, 105(3), p.034338_1 - 034338_9, 2022/03
被引用回数:3 パーセンタイル:44.35(Physics, Nuclear)The neutron-deficient region of isotopes around =82 is the best studied example of low-energy shape coexistence in nuclei. In this work, the internal transition decay and
decay of the 53.3-ms isomeric state in
Tl were studied at ISOLDE, CERN. The branching for the internal decay was measured to be 98.5(4)%, while the much weaker
decay branching is only about 1.4(4)%. The new results include the first identification of an
transition feeding the 3/2
excited state in
Tl. Three
decays from the
Tl isomer were also oserved, and revealed the population of a candidate 9/2
state in
Au which has been linked to shape coexistence in the Au nuclei. It is expected that similarly weak
decays from isomeric states may be found also in neighbouring Tl isotopes.
Abudinn, 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:4 パーセンタイル:37.56(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.
Cao, L.*; 谷田 聖; Belle Collaboration*; 他199名*
Physical Review Letters, 127(26), p.261801_1 - 261801_8, 2021/12
被引用回数:6 パーセンタイル:50.22(Physics, Multidisciplinary)The first measurements of differential branching fractions of inclusive semileptonic decays are performed using the full Belle data set of 711 fb
of integrated luminosity at the
resonance and for
. Differential branching fractions are reported as a function of the lepton momentum, the four-momentum-transfer squared, light-cone momenta, the hadronic mass, and the hadronic mass squared. They are obtained by subtracting the backgrounds from semileptonic
decays and other processes, and corrected for resolution and acceptance effects. The measured distributions are compared to predictions from inclusive and hybrid
calculations.
Atmacan, H.*; 谷田 聖; Belle Collaboration*; 他219名*
Physical Review D, 104(9), p.L091105_1 - L091105_9, 2021/11
被引用回数:7 パーセンタイル:43.47(Astronomy & Astrophysics)We present a search for the lepton-flavor-violating decays , where
, using the full data sample of
pairs recorded by the Belle detector at the KEKB asymmetric-energy
collider. We use events in which one
meson is fully reconstructed in a hadronic decay mode. The
lepton is reconstructed indirectly using the momentum of the reconstructed
and that of the
from the signal decay. We find no evidence for
decays and set upper limits on their branching fractions at 90% confidence level of
(
)
and
(
)
.
Li, S. X.*; 谷田 聖; Belle Collaboration*; 他193名*
Physical Review D, 104(7), p.072008_1 - 072008_8, 2021/10
被引用回数:5 パーセンタイル:27.12(Astronomy & Astrophysics)Using 980.6 of data collected with the Belle detector operating at the KEKB asymmetric-energy
collider, we present a measurement of the branching fraction of the singly Cabibbo-suppressed decay
. A clear
signal is observed for
with a statistical significance of 9.1 standard deviations, and we measure the ratio of branching fractions
, from which we infer the branching fraction
. The first quoted uncertainty is statistical, the second systematic, and the third from the reference mode
.
Li, Y.*; 谷田 聖; Belle Collaboration*; 他190名*
Physical Review D, 104(5), p.052005_1 - 052005_9, 2021/09
被引用回数:12 パーセンタイル:61.30(Astronomy & Astrophysics)Using a data sample of 980~fb collected with the Belle detector operating at the KEKB asymmetric-energy
collider, we present evidence for the
in the resonant substructure of
(
=
+
) decays. The significance of the
signal is 4.2
after considering the systematic uncertainties. The ratio of the branching fraction of
relative to that of
is calculated to be 0.220
0.059(stat.)
0.035(syst.). The individual ratios of the branching fractions of the two isospin modes are also determined, and found to be
=(9.6
3.2(stat.)
1.8(syst.))% and
= (5.5
2.8(stat.)
0.7(syst.))%.
Nisar, N. K.*; 谷田 聖; Belle Collaboration*; 他197名*
Physical Review D, 104(3), p.L031101_1 - L031101_8, 2021/08
被引用回数:1 パーセンタイル:7.09(Astronomy & Astrophysics)We report the results of the first search for the decay using
of data collected at the
resonance with the Belle detector at the KEKB asymmetric-energy
collider. We observe no significant signal and set a 90% confidence-level upper limit of
on the branching fraction of this decay.
佐藤 健太*; 谷田 聖; 他19名*
Proceedings of Science (Internet), 358, p.413_1 - 413_8, 2021/07
The Relativistic Heavy Ion Collider forward (RHICf) experiment aims at understanding the high-energy hadronic interaction by measuring the cross sections of very forward neutral particles in proton-proton collisions at = 510 GeV. For the analysis of the photon measurement, the trigger efficiency and the particle identification performance are studied by using the Monte Carlo simulation data and the experimental data. In the RHICf operation, two kinds of trigger modes (Shower, HighEM) were implemented. The trigger efficiency of the Shower trigger is 100% for photons with the energies more than 20 GeV. The HighEM trigger is designed to detect high energy photons effectively, and the trigger efficiency of the HighEM trigger is 90% for photons with the energies more than 130 GeV. The correction factor for the photon identification is calculated by using the efficiency and purity. It is found that this correction does not make a sizeable effect on the shape of the energy spectrum because the energy dependency of the factor is small.
McNeil, J. T.*; 谷田 聖; Belle Collaboration*; 他193名*
Physical Review D, 103(11), p.112002_1 - 112002_11, 2021/06
被引用回数:4 パーセンタイル:27.12(Astronomy & Astrophysics)Using the entire data sample of
integrated luminosity collected with the Belle detector at the KEKB asymmetric-energy
collider, we present an amplitude analysis measuring the branching fractions of the Cabibbo-allowed,
-exchange resonant decay
with a polarized
and the non-resonant decay via a direct process
. We present these measurements, relative to the normalization mode
, and find branching ratios
=
and
=
which suggest that only minor cusping peaks occur in the combinatorial background of
due to these
decays.
Oskin, P.*; 谷田 聖; Belle Collaboration*; 他198名*
Physical Review D, 102(9), p.092011_1 - 092011_8, 2020/11
被引用回数:0 パーセンタイル:0.00(Astronomy & Astrophysics)Using data collected in the Belle experiment at the KEKB asymmetric-energy collider we search for transitions
,
and
. No significant signals are observed and we set 90% confidence level upper limits on the corresponding visible cross sections:
and
, respectively.
Chilikin, K.*; 谷田 聖; Belle Collaboration*; 他194名*
Journal of High Energy Physics (Internet), 2020(5), p.34_1 - 34_22, 2020/05
被引用回数:4 パーセンタイル:24.30(Physics, Particles & Fields)The first dedicated search for the is carried out using the decays
,
,
, and
with
. No significant signal is found. For the
mass range between
and
, the branching-fraction upper limits are determined to be
,
,
, and
at 90% C. L. The analysis is based on the 711
data sample collected on the
resonance by the Belle detector, which operated at the KEKB asymmetric-energy
collider.