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論文

Unique band structure of pressure induced semiconducting state in SmS characterized by $^{33}$ S-nuclear magnetic resonance measurements

吉田章吾*; 芳賀芳範; 藤井拓斗*; 中井祐介*; 水戸毅*; 他8名*

Journal of the Physical Society of Japan, 93(1), p.013702_1 - 013702_5, 2024/01

https://doi.org/10.7566/JPSJ.93.013702

被引用回数：0 パーセンタイル：0.02(Physics, Multidisciplinary)

In Kondo insulators, a small energy gap evolves only at low temperatures. In this study, $^{33}$ S-nuclear magnetic resonance measurements under high pressures are performed to clarify the electronic structure of SmS. The spin-lattice relaxation time, consisting of multiple components, was analyzed based on a periodic Anderson model with Bayesian inference, leading to a peculiar small gap state arising from strong hybridization.

論文

Selective epitaxial growth of Ca $_{2}$ NH and CaNH thin films by reactive magnetron sputtering under hydrogen partial pressure control

Chon, S.*; 福谷克之; 他8名*

Journal of Physical Chemistry Letters (Internet), 13(43), p.10169 - 10174, 2022/11

https://doi.org/10.1021/acs.jpclett.2c02617

被引用回数：0 パーセンタイル：0.01(Chemistry, Physical)

Calcium compounds with N and H are promising catalysts for NH $_{3}$ conversion, and their epitaxial thin films provide a platform to quantitatively understand the catalytic activities. Here we report the selective epitaxial growth of Ca $_{2}$ NH and CaNH thin films by controlling the hydrogen partial pressure ( $P_{H_{2}}$ ) during reactive magnetron sputtering. We find that the hydrogen charge states can be tuned by $P_{H_{2}}$ : Ca $_{2}$ NH containing H $^{-}$ is formed at $P_{H_{2}}<0.04$ Pa, while CaNH containing H $^{+}$ is formed at $P_{H_{2}}>0.04$ Pa. In situ plasma emission spectroscopy reveals that the intensity of the Ca atomic emission (422 nm) decreases as $P_{H_{2}}$ increases, suggesting that Ca reacts with H $_{2}$ and N $_{2}$ to form Ca $_{2}$ NH at lower $P_{H_{2}}$ , whereas at higher $P_{H_{2}}$ , CaH $_{x}$ is first formed on the target surface and then sputtered to produce CaNH. This study provides a novel route to control the hydrogen charge states in Ca-N-H epitaxial thin films.

論文

Differential cross sections and photon beam asymmetries of photoproduction on the proton at = 1.3-2.4 GeV

橋本敏和*; 土川雄介; LEPS BGOegg Collaboration*; 他58名*

Physical Review C, 106(3), p.035201_1 - 035201_15, 2022/09

https://doi.org/10.1103/PhysRevC.106.035201

被引用回数：3 パーセンタイル：64.25(Physics, Nuclear)

We report exclusive measurements for the photoproduction on a proton target. The differential cross sections and photon beam asymmetries of the reaction are measured in a center-of-mass energy () range of 1.82-2.32 GeV and a polar angle range of $-1.0 < cos theta_{c.m.}^eta < 0.6$ by using a large acceptance calorimeter (BGOegg) and forward-angle charged-particle detectors at the SPring-8 LEPS2 beamline. The reaction is identified with a kinematic fitting method to select a recoil proton and two photons produced in an meson decay. A bump structure at W = 2.0-2.3 GeV in the differential cross section is confirmed at extremely backward polar angles, where the existing data are inconsistent with each other. This bump structure is likely associated with high-spin resonances that couple with quarks. The photon beam asymmetries in a wide polar angle range for the photon beam energies above 2.1 GeV are reported for the first time, providing an additional constraint to nucleon resonance studies at high energies.

論文

High accuracy, high resolution $^{235}$ U(n,f) cross section from n_TOF (CERN) from 18 meV to 10 keV

Mastromarco, M.*; Amaducci, S.*; Colonna, N.*; 木村敦; 他118名*

European Physical Journal A, 58(8), p.147_1 - 147_13, 2022/08

https://doi.org/10.1140/epja/s10050-022-00779-7

被引用回数：2 パーセンタイル：49.92(Physics, Nuclear)

The $^{235}$ U(n,f) cross section was measured in a wide energy range (18 meV - 170 keV) at the n_TOF facility at CERN, relative to Li(n,t) and $^{10}$ B(n,) standard reactions, with a setup based on a stack of six samples and six silicon detectors placed in the neutron beam. A resonance analysis has been performed up to 200 eV, with the code SAMMY. A good agreement, within 0.5%, is found on average between the new results and the latest evaluated data files ENDF/B-VIII.0 and JEFF-3.3, as well as with respect to the broad group average fission cross section established in the framework of the standard working group of IAEA. However, some discrepancies, of up to 4%, are still present in some specific energy regions.

論文

Measurements of strong-interaction effects in kaonic-helium isotopes at sub-eV precision with X-ray microcalorimeters

橋本直; 谷田聖; 他68名*

Physical Review Letters, 128(11), p.112503_1 - 112503_6, 2022/03

https://doi.org/10.1103/PhysRevLett.128.112503

被引用回数：8 パーセンタイル：76.56(Physics, Multidisciplinary)

We have measured the transition X-rays of kaonic He and He atoms using superconducting transition-edge-sensor microcalorimeters with an energy resolution better than 6 eV (FWHM). We determined the energies to be (stat) (syst) eV and (stat) (syst) eV, and widths to be (stat) (syst) eV and (stat) (stat) eV, for kaonic He and He, respectively. These values are nearly 10 times more precise than in previous measurements. Our results exclude the large strong-interaction shifts and widths that are suggested by a coupled-channel approach, and agree with calculations based on optical-potential models.

論文

Producing gold at ISOLDE-CERN

Barzakh, A. E.*; Andreyev, A. N.; Atanasov, D.*; Cubiss, J. G.*; Harding, R. D.*; Al Monthery, M.*; Althubiti, N. A.*; Andel, B.*; 他38名*

Nuclear Instruments and Methods in Physics Research B, 513, p.26 - 32, 2022/02

https://doi.org/10.1016/j.nimb.2021.12.011

被引用回数：0 パーセンタイル：0.02(Instruments & Instrumentation)

The yield of 18 beams of radioactive gold nuclei produced by irradiating the ISOLDE uranium target with 1.4-GeV protons was measured. The production-efficiency dependence on the half-life was derived using the in-target production calculations. Three release models were tested to describe the results. Irregularities in the efficiency curve for 3 long-lived high-spin gold isomers ( $^{187,191,193}$ Au) were found, which require further investigation.

論文

Study of and $e^+e^-to Upsilon(rm 1S)eta^{prime}$ at GeV with the Belle detector

Kovalenko, E.*; 谷田聖; Belle Collaboration*; 他181名*

Physical Review D, 104(11), p.112006_1 - 112006_12, 2021/12

https://doi.org/10.1103/PhysRevD.104.112006

被引用回数：0 パーセンタイル：0.01(Astronomy & Astrophysics)

We report the first observation of the processes at =10.866 GeV with a and significance respectively. The measured Born cross sections are pb, and pb. We also set the upper limit on the cross section of the process $e^+e^- to Upsilon(rm 1S)eta^{prime}$ to be $sigma(e^+e^- to Upsilon(rm 1S)eta^{prime}) < 0.035$ ~pb at CL. The results are obtained with the data sample collected with the Belle detector at the KEKB asymmetric-energy collider in the energy range from 10.63 GeV to 11.02 GeV.

論文

Precise measurement of the and lifetimes at Belle II

Abudinn, F.*; 谷田聖; Belle II Collaboration*; 他385名*

Physical Review Letters, 127(21), p.211801_1 - 211801_9, 2021/11

https://doi.org/10.1103/PhysRevLett.127.211801

被引用回数：6 パーセンタイル：60.19(Physics, Multidisciplinary)

We report a measurement of the and lifetimes using and decays reconstructed in $e^+e^-to cbar{c}$ 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 $72,{rm fb}^{-1}$ . The results, $tau(D^0) = 410.5pm1.1,{rm(stat)}pm0.8,{rm(syst.)},{rm fs}$ and $tau(D^+) = 1030.4pm4.7,{rm(stat)}pm3.1,{rm(syst.)},{rm fs}$ , are the most precise to date and are consistent with previous determinations.

論文

Search for lepton-flavor-violating tau-lepton decays to at Belle

宇野健太*; 谷田聖; Belle Collaboration*; 他181名*

Journal of High Energy Physics (Internet), 2021(10), p.19_1 - 19_12, 2021/10

https://doi.org/10.1007/JHEP10(2021)019

被引用回数：11 パーセンタイル：63.98(Physics, Particles & Fields)

Charged lepton flavor violation is forbidden in the Standard Model but possible in several new physics scenarios. In many of these models, the radiative decays $tau^{pm}rightarrowell^{pm}gamma$ () are predicted to have a sizeable probability, making them particularly interesting channels to search at various experiments. An updated search via $tau^{pm}rightarrowell^{pm}gamma$ using full data of the Belle experiment, corresponding to an integrated luminosity of 988 fb $^{-1}$ , is reported for charged lepton flavor violation. No significant excess over background predictions from the Standard Model is observed, and the upper limits on the branching fractions, $mathcal{B}(tau^{pm}rightarrow mu^{pm}gamma)$ $4.2times10^{-8}$ and $mathcal{B}(tau^{pm}rightarrow e^{pm}gamma)$ $5.6times10^{-8}$ , are set at 90% confidence level.

論文

Unveiling unconventional magnetism at the surface of SrRuO

Fittipaldi, R.*; Hartmann, R.*; Mercaldo, M. T.*; 小森祥央*; Bjrlig, A.*; 髭本亘; 前野悦輝*; Di Bernardo, A.*; 他18名*

Nature Communications (Internet), 12, p.5792_1 - 5792_9, 2021/10

https://doi.org/10.1038/s41467-021-26020-5

被引用回数：11 パーセンタイル：68.91(Multidisciplinary Sciences)

層状酸化物ペロブスカイト構造を持つSrRuOの超伝導は長年にわたり議論がなされており、その理解のために背景となる常伝導状態の振る舞いは極めて重要となる。本研究では低エネルギーミュオンを用いることで、表面における磁性の存在を見出した。この磁性は50Kよりも高い温度から見られており、他の物質の状態とも深い関連があるものと考えられる。

論文

Measurement of the differential cross sections of the elastic scattering in momentum range 470 to 850 MeV/

三輪浩司*; 藤田真奈美; 長谷川勝一; 細見健二; 市川裕大; 今井憲一*; 七村拓野; 成木恵; 佐甲博之; 佐藤進; et al.

Physical Review C, 104(4), p.045204_1 - 045204_20, 2021/10

https://doi.org/10.1103/PhysRevC.104.045204

被引用回数：13 パーセンタイル：88.31(Physics, Nuclear)

A high statistics scattering experiment is performed at the J-PARC Hadron Experimental Facility. Momentum-tagged s running in a liquid hydrogen target are accumulated by detecting the reaction with a high intensity beam of 20 M/spill. The differential cross sections of the elastic scattering were derived with a drastically improved accuracy by identifying approximately 4,500 events from 1.72 10 . The derived differential cross section shows a clear forward-peaking angular distribution for a momentum range from 470 to 850 MeV/. The accurate data will impose a strong constraint on the theoretical models of the baryon-baryon interactions.

論文

Measurement of branching fractions and search for violation in $D^{0}topi^{+}pi^{-}eta$ , $D^{0}to K^{+}K^{-}eta$ , and $D^{0}tophieta$ at Belle

Li, L. K.*; 谷田聖; Belle Collaboration*; 他187名*

Journal of High Energy Physics (Internet), 2021(9), p.75_1 - 75_21, 2021/09

https://doi.org/10.1007/JHEP09(2021)075

被引用回数：1 パーセンタイル：10.04(Physics, Particles & Fields)

We measure the branching fractions and asymmetries for the singly Cabibbo-suppressed decays $D^{0}topi^{+}pi^{-}eta$ , $D^{0}to K^{+}K^{-}eta$ , and $D^{0}tophieta$ , using 980 fb $^{-1}$ of data from the Belle experiment at the KEKB collider. We obtain $mathcal{B}(D^{0}topi^{+}pi^{-}eta) = [1.22pm 0.02,({rm stat})pm 0.02,({rm syst})pm 0.03,(mathcal{B}_{rm ref})]times 10^{-3},, mathcal{B}(D^{0}to K^{+}K^{-}eta) = [1.80,^{+0.07}_{-0.06},({rm stat})pm 0.04,({rm syst})pm 0.05,(mathcal{B}_{rm ref})]times 10^{-4},, mathcal{B}(D^{0}tophieta) = [1.84pm 0.09,({rm stat})pm 0.06,({rm syst})pm 0.05,(mathcal{B}_{rm ref})]times 10^{-4},,$ where the third uncertainty ( $mathcal{B}_{rm ref}$ ) is from the uncertainty in the branching fraction of the reference mode $D^{0} to K^{-}pi^{+}eta$ . The color-suppressed decay $D^{0}tophieta$ is observed for the first time, with very high significance. The results for the asymmetries are $A_{CP}(D^{0}topi^{+}pi^{-}eta) = [0.9pm 1.2,({rm stat})pm 0.5,({rm syst})]%,, A_{CP}(D^{0}to K^{+}K^{-}eta) = [-1.4pm 3.3,({rm stat})pm 1.1,({rm syst})]%,, A_{CP}(D^{0}tophieta) = [-1.9pm 4.4,({rm stat})pm 0.6,({rm syst})]%,.$ The results for $D^{0}topi^{+}pi^{-}eta$ are a significant improvement over previous results. The branching fraction and $A_{CP}$ results for $D^{0}to K^{+}K^{-}eta$ , and the $A_{CP}$ result for $D^{0}tophieta$ , are the first such measurements. No evidence for violation is found in any of these decays.

論文

Measurements of the branching fractions of the semileptonic decays $Xi_{c}^{0} to Xi^{-} ell^{+} nu_{ell}$ and the asymmetry parameter of $Xi_{c}^{0} to Xi^{-} pi^{+}$

Li, Y. B.*; 谷田聖; Belle Collaboration*; 他182名*

Physical Review Letters, 127(12), p.121803_1 - 121803_8, 2021/09

https://doi.org/10.1103/PhysRevLett.127.121803

被引用回数：27 パーセンタイル：92.21(Physics, Multidisciplinary)

Using data samples of 89.5 and 711 fb $^{-1}$ recorded at energies of and GeV, respectively, with the Belle detector at the KEKB collider, we report measurements of branching fractions of semileptonic decays $Xi_{c}^{0} to Xi^{-} ell^{+} nu_{ell}$ ( or ) and the -asymmetry parameter of $Xi_{c}^{0} to Xi^{-} pi^{+}$ decay. The branching fractions are measured to be ${cal B}(Xi_{c}^{0} to Xi^{-} e^{+} nu_{e}$ )=()% and ${cal B}(Xi_{c}^{0} to Xi^{-} mu^{+} nu_{mu}$ )=()%, and the decay parameter $alpha_{Xipi}$ is measured to be with much improved precision compared to the current world average. The corresponding ratio ${cal B}(Xi_{c}^{0} to Xi^{-} e^{+} nu_{e})$ / ${cal B}(Xi_{c}^{0} to Xi^{-} mu^{+} nu_{mu})$ is 1.03 0.05 0.07, which is consistent with the expectation of lepton flavor universality. The first measured asymmetry parameter ${cal A}_{CP} = (alpha_{Xi^{-}pi^{+}} + alpha_{bar{Xi}^{+}pi^{-}})/(alpha_{Xi^{-}pi^{+}} - alpha_{bar{Xi}^{+}pi^{-}}) = 0.024 pm 0.052 pm 0.014$ is found to be consistent with zero. The first and the second uncertainties above are statistical and systematic, respectively, while the third ones arise due to the uncertainty of the $Xi_{c}^{0} to Xi^{-} pi^+$ branching fraction.

論文

Measurements of branching fractions and asymmetry parameters of $Xi^0_cto Lambdabar K^{0}$ , $Xi^0_cto Sigma^0bar K^{0}$ , and $Xi^0_cto Sigma^+K^{*-}$ decays at Belle

Jia, S.*; 谷田聖; Belle Collaboration*; 他186名*

Journal of High Energy Physics (Internet), 2021(6), p.160_1 - 160_13, 2021/06

https://doi.org/10.1007/JHEP06(2021)160

被引用回数：5 パーセンタイル：36.61(Physics, Particles & Fields)

Using a data sample of 980 fb $^{-1}$ collected with the Belle detector at the KEKB asymmetric-energy collider, we study the processes of $Xi^0_cto Lambdabar K^{*0}$ , $Xi^0_cto Sigma^0bar K^{*0}$ , and $Xi^0_cto Sigma^+K^{*-}$ for the first time. The relative branching ratios to the normalization mode of are measured to be ${cal B}(Xi^0_cto Lambdabar K^{*0})/{cal B}(Xi_c^0 to Xi^-pi^+)=0.18 pm 0.02({rm stat.})pm0.01({rm syst.}),$ ${cal B}(Xi^0_cto Sigma^0bar K^{*0})/{cal B}(Xi_c^0to Xi^-pi^+)=0.69pm0.03({rm stat.})pm0.03({rm syst.}),$ ${cal B}(Xi^0_cto Sigma^+K^{*-})/{cal B}(Xi_c^0to Xi^-pi^+)=0.34pm0.06({rm stat.})pm0.02({rm syst.}),$ where the uncertainties are statistical and systematic, respectively. We obtain the branching fractions of $Xi^0_cto Lambdabar K^{*0}$ , $Xi^0_cto Sigma^0bar K^{*0}$ , and $Xi^0_cto Sigma^+K^{*-}$ to be ${cal B}(Xi^0_cto Lambdabar K^{*0})=(3.3pm0.3({rm stat.})pm0.2({rm syst.})pm1.0({rm ref.}))times10^{-3},$ ${cal B}(Xi^0_cto Sigma^0bar K^{*0})=(12.4pm0.5({rm stat.})pm0.5({rm syst.})pm3.6({rm ref.}))times10^{-3},$ ${cal B}(Xi^0_cto Sigma^+K^{*-})=(6.1pm1.0({rm stat.})pm0.4({rm syst.})pm1.8({rm ref.}))times10^{-3},$ where the uncertainties are statistical, systematic, and from ${cal B}(Xi_c^0 to Xi^-pi^+)$ , respectively. The asymmetry parameters $alpha(Xi^0_cto Lambdabar K^{*0})$ and $alpha(Xi^0_cto Sigma^+K^{*-})$ are and , respectively, where the uncertainties are statistical followed by systematic.

論文

Measurement of the energy dependence of the $e^+e^-to Bbar{B}$ , $Bbar{B}^$ and $B^bar{B}^*$ exclusive cross sections

Mizuk, R.*; 谷田聖; Belle Collaboration*; 他188名*

Journal of High Energy Physics (Internet), 2021(6), p.137_1 - 137_35, 2021/06

https://doi.org/10.1007/JHEP06(2021)137

被引用回数：7 パーセンタイル：50.25(Physics, Particles & Fields)

We report the first measurement of the exclusive cross sections $e^+e^-to Bbar{B}$ , $e^+e^-to Bbar{B}^*$ , and $e^+e^-to B^*bar{B}^*$ in the energy range from 10.63 GeV to 11.02 GeV. The mesons are fully reconstructed in a large number of hadronic final states and the three channels are identified using a beam-constrained-mass variable. The shapes of the exclusive cross sections show oscillatory behavior with several maxima and minima. The results are obtained using data collected by the Belle experiment at the KEKB asymmetric-energy collider.

論文

J-PARC E07; Systematic study of double strangeness system with hybrid emulsion method

吉田純也; 赤石貴也; 藤田真奈美; 長谷川勝一; 橋本直; 細見健二; 市川真也; 市川裕大; 今井憲一*; Kim, S.; et al.

JPS Conference Proceedings (Internet), 33, p.011112_1 - 011112_8, 2021/03

https://doi.org/10.7566/JPSCP.33.011112

J-PARC E07 is the most ambitious and complex emulsion experiment to date investigating double hypernuclei with Hybrid emulsion method. The physics run at the K1.8 beam line in the J-PARC hadron experimental facility have been completed in 2017. The emulsion sheets are presently being analyzed with dedicated optical microscopes. Current statistics are estimated to be more 3 times than that of previous experiments. Quantitative data on the and interaction are being accumulated successfully via analysis of double and hypernuclei. Multiple hypernucleus candidates suggests several features about hypernucleus that the identification efficiency of $^{15}_Xi$ C is significantly higher than other mode, many daughters of $^{15}_Xi$ C are identified as He or Be, and multiple bound states of exist in the $^{14}$ N nucleus. An analysis of X-ray spectroscopy of hyperatoms are ongoing.

論文

Measurement of branching fraction and search for violation in

Mohanty, S.*; 谷田聖; Belle Collaboration*; 他184名*

Physical Review D, 103(5), p.052013_1 - 052013_9, 2021/03

https://doi.org/10.1103/PhysRevD.103.052013

被引用回数：0 パーセンタイル：0.01(Astronomy & Astrophysics)

We report the measurement of branching fractions and -violation asymmetries in decays based on a $711,{rm fb}^{-1}$ data sample containing events. The data were recorded at the resonance with the Belle detector at the KEKB asymmetric-energy collider. For , the branching fraction and -violation asymmetry measured below the $eta_{c}$ threshold ( $m_{phiphi} < 2.85,{rm GeV}/c^2$ ) are $[3.43^{,+,0.48}_{,-,0.46}({rm stat})pm 0.22({rm syst})] times10^{-6}$ and , respectively. Similarly, the branching fraction obtained for below the $eta_{c}$ threshold is $[3.02^{,+,0.75}_{,-,0.66} ({rm stat})pm ,0.20({rm syst})]times10^{-6}$ . We also measure the -violation asymmetry for within the $eta_{c}$ region ( $m_{phiphi}in [2.94,3.02],{rm GeV}/c^2$ ) to be .

論文

Transverse momentum dependent forward neutron single spin asymmetries in transversely polarized collisions at GeV

Acharya, U. A.*; 長谷川勝一; 今井憲一*; 佐甲博之; 佐藤進; 谷田聖; PHENIX Collaboration*; 他308名*

Physical Review D, 103(3), p.032007_1 - 032007_8, 2021/02

https://doi.org/10.1103/PhysRevD.103.032007

被引用回数：2 パーセンタイル：19.82(Astronomy & Astrophysics)

In 2015, the PHENIX collaboration has measured very forward () single-spin asymmetries of inclusive neutrons in transversely polarized proton-proton and proton-nucleus collisions at a center of mass energy of 200 GeV. A previous publication from this data set concentrated on the nuclear dependence of such asymmetries. In this measurement the explicit transverse-momentum dependence of inclusive neutron single spin asymmetries for proton-proton collisions is extracted using a bootstrapping-unfolding technique on the transverse momenta. This explicit transverse-momentum dependence will help improve the understanding of the mechanisms that create these asymmetries.

論文

Observation of Coulomb-assisted nuclear bound state of - $^{14}$ N system

早川修平; 藤田真奈美; 長谷川勝一; 橋本直; 細見健二; 市川裕大; 今井憲一*; 七村拓野; 成木恵; 佐甲博之; et al.

Physical Review Letters, 126(6), p.062501_1 - 062501_6, 2021/02

https://doi.org/10.1103/PhysRevLett.126.062501

被引用回数：34 パーセンタイル：95.02(Physics, Multidisciplinary)

In an emulsion-counter hybrid experiment performed at J-PARC, a absorption event was observed which decayed into twin single- hypernuclei. Kinematic calculations enabled a unique identification of the reaction process as $Xi^{-} + ^{14}$ N $rightarrow ^{10}_Lambda$ Be + He. For the binding energy of the $Xi^{-}$ hyperon in the - $^{14}$ N system a value of MeV was deduced. The energy level of is likely a nuclear state which indicates a weak - coupling.

論文

Search for transitions from and to and with emission of an meson

Oskin, P.*; 谷田聖; Belle Collaboration*; 他198名*

Physical Review D, 102(9), p.092011_1 - 092011_8, 2020/11

https://doi.org/10.1103/PhysRevD.102.092011

被引用回数：0 パーセンタイル：0.01(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.