A5073798742- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Nuclear physics research studies
- Particle Detector Development and Performance
- Computational Physics and Python Applications
- Particle Accelerators and Free-Electron Lasers
- Superconducting Materials and Applications
- Dark Matter and Cosmic Phenomena
- Neutrino Physics Research
- Advanced NMR Techniques and Applications
- Black Holes and Theoretical Physics
- Atomic and Subatomic Physics Research
- Nuclear reactor physics and engineering
- Nuclear Physics and Applications
- Radiation Detection and Scintillator Technologies
- Medical Imaging Techniques and Applications
- Quantum, superfluid, helium dynamics
- Astrophysics and Cosmic Phenomena
- X-ray Spectroscopy and Fluorescence Analysis
- Atomic and Molecular Physics
- Particle accelerators and beam dynamics
- Radiopharmaceutical Chemistry and Applications
- Gamma-ray bursts and supernovae
- High-pressure geophysics and materials
Japan Atomic Energy Agency
2016-2025
Brookhaven National Laboratory
2016-2025
Seoul National University
2016-2025
RIKEN Nishina Center
2013-2024
Advanced Science Research Center
2015-2024
RIKEN BNL Research Center
2015-2024
Augustana University
2014-2024
Bhabha Atomic Research Centre
2017-2024
Banaras Hindu University
2006-2024
Abilene Christian University
2003-2023
A double-hyperfragment event has been found in a hybrid-emulsion experiment. It is identified uniquely as the sequential decay of ( 6)(LambdaLambda)He emitted from Xi(-) hyperon nuclear capture at rest. The mass and Lambda-Lambda interaction energy DeltaB(LambdaLambda) have measured for first time devoid ambiguities due to possibilities excited states. value 1.01+/-0.20(+0.18)(-0.11) MeV. This demonstrates that weakly attractive.
A hybrid experiment with nuclear emulsion and scintillating-fiber detectors (KEK-E373) has been performed to search for double-strangeness systems. Among about 10${}^{3}$ events of ${\ensuremath{\Xi}}^{\ensuremath{-}}$ hyperons captured at rest by nuclei, we have observed four which clearly show the topology cascade weak decays double-$\ensuremath{\Lambda}$ hypernuclei including ``Nagara'' event. Regarding Nagara event, values two-$\ensuremath{\Lambda}$ binding energy...
The energy spacing of the spin-doublet states in ${}_{\mathrm{\ensuremath{\Lambda}}}^{4}$He hypernucleus indicate a large spin dependent charge symmetry breaking $\mathrm{\ensuremath{\Lambda}}\phantom{\rule{0}{0ex}}N$ interaction.
In an emulsion-counter hybrid experiment performed at J-PARC, a $Ξ^-$ absorption event was observed which decayed into twin single-$Λ$ hypernuclei. Kinematic calculations enabled unique identification of the reaction process as $Ξ^{-} + ^{14}$N$\ \rightarrow\ ^{10}_Λ$Be $^5_Λ$He. For binding energy $Ξ^{-}$ hyperon in $Ξ^-$-$^{14}$N system value $1.27 \pm 0.21$ MeV deduced. The level is likely nuclear $1p$ state indicates weak $ΞN$-$ΛΛ$ coupling.
We report on the first measurement of a hypernuclear gamma-transition probability. gamma rays emitted in E2(5/2(+)-->1/2(+)) transition (7)(Lambda)Li were detected by large-acceptance germanium detector array (Hyperball), and lifetime parent state ( 5/2(+)) was determined Doppler shift attenuation method. The obtained result, 5.8(+0.9)(-0.7)+/-0.7 ps, then converted into reduced probability [ B(E2)] to be B(E2;5/2(+)-->1/2(+)) = 3.6+/-0.5(+0.5)(-0.4) e(2) fm(4). Compared with B(E2)...
Excitation energy spectra of 89ΛY, 51ΛV, and 12ΛC have been measured via the (π+,K+) reaction by using SKS spectrometer at K6 beam line in KEK 12-GeV Proton Synchrotron. In 89ΛY spectrum, obtained with an resolution 1.65 MeV (FWHM) highest statistics so far, we succeeded clearly observing a characteristic fine structure heavy Λ hypernuclear systems precisely obtaining series single-particle energies very wide excitation range more than 20 MeV, for first time. Also 51ΛV similar to that was...
With a germanium detector array (Hyperball), we observed two gamma-ray peaks corresponding to the transitions (5/2(+)-->1/2(+) and 3/2(+)-->1/2(+)) in (9)(Lambda)Be hypernucleus which was produced by 9Be(K-,pi(-)) reaction. The energies of gamma rays are 3029 +/- 2 1 keV 3060 keV. energy difference measured be 31.4(+2.5)(-3.6) keV, indicates very small Lambda-spin-dependent spin-orbit force between Lambda nucleon. This is smallest level splitting far ever hypernucleus.
Using a large-acceptance germanium detector array (Hyperball), we have observed spin-flip M1 gamma transition between the ground-state spin doublet of (7)(Lambda)Li (3/2(+)-->1/2(+)). The energy 691.7+/-0.6(stat)+/-1.0(syst) keV provides crucial information on strength spin-spin interaction Lambda and nucleon. This is first observation well-identified hypernuclear transitions using detectors.
In this document the PHENIX collaboration proposes a major upgrade to detector at Relativistic Heavy Ion Collider. This upgrade, sPHENIX, enables an extremely rich jet and beauty quarkonia physics program addressing fundamental questions about nature of strongly coupled quark-gluon plasma (QGP), discovered experimentally RHIC be perfect fluid. The startling dynamics QGP on fluid-like length scales is emergent property quantum chromodynamics (QCD), seemingly implicit in Lagrangian but...
We observed a distinct peak in the Λp invariant mass spectrum of He3(K−,Λp)n, well below mK+2mp, i.e., threshold K− to be bound two protons. By selecting relatively large momentum-transfer region q=350∼650 MeV/c, one can kinematically separate from quasi-free process, K‾N→K‾N followed by non-resonant absorption spectator-nucleons K‾NN→ΛN. found that simplest fit gives us Breit–Wigner pole position at BKpp=47±3(stat.)−6+3(sys.) MeV having width ΓKpp=115±7(stat.)−20+10(sys.) MeV, and S-wave...
Bound-systems of $\Xi^-$--$^{14}_{}{\rm N}$ are studied via $\Xi^-$ capture at rest followed by emission a twin single-$\Lambda$ hypernucleus in the emulsion detectors. Two events forming extremely deep bound states were obtained analysis hybrid method E07 experiment J-PARC and reanalysis E373 KEK-PS. The decay mode one event was assigned as $\Xi^-+^{14}_{}{\rm N}\to^{5}_{\Lambda}{\rm He}$+$^{5}_{\Lambda}{\rm He}$+$^{4}_{}{\rm He}$+n. Since there no excited for daughter particles, binding...
The spin-orbit splitting of Lambda single-particle states in (13)(Lambda)C was measured. 13C(K-,pi(-))(13)(Lambda)C reaction used to excite both the 1/2(-) and 3/2(-) simultaneously, which have predominantly 12C(0(+)) x p(Lambda) configuration. gamma rays from ground state were measured coincidence with pi(-)'s, by ls found be 152+/-54(stat)+/-36(syst) keV. value is 20-30 times smaller than exhibited nuclear shell model. This gives us new insight into YN interaction.
We have studied the (pi(-),K+) reaction on a silicon target to investigate sigma-nucleus potential. The inclusive spectrum was measured at beam momentum of 1.2 GeV/c with an energy resolution 3.3 MeV (FWHM) by employing superconducting kaon spectrometer system. compared theoretical calculations within framework distorted-wave impulse approximation, which demonstrates that strongly repulsive potential nonzero size imaginary part reproduces observed spectrum.
An experiment demonstrating the production of double-Lambda hypernuclei in (K(-),K(+)) reactions on (9)Be was carried out at D6 line BNL alternating-gradient synchrotron. The technique observation pions produced sequential mesonic weak decay, each pion associated with one unit strangeness change. results indicate a significant number double hypernucleus (4)(double Lambda)H and twin (4)(Lambda)H (3)(Lambda)H. relevant decay chains are discussed simple model mechanism is presented. implication...
In order to study the Sigma-nucleus optical potential, we measured inclusive (pi^-,K^+) spectra on medium-to-heavy nuclear targets: CH_2, Si, Ni, and Bi. The CH_2 target was used calibrate excitation energy scale by using elementary process p + pi^- -> K^+ Sigma^-, where C spectrum also extracted. calibration done with +-0.1 MeV precision. angular distribution of cross section measured, agreed well previous bubble chamber data, but better statistics, magnitudes sections were calibrated. All...
The H-dibaryon resonance was sought by a ΛΛ invariant mass spectrum that obtained the C12 (K−,K+ΛΛX) reactions. We observed bump near threshold, as reported previous experiment (KEK E224), with better statistics. Data were compared results of cascade model calculation including final state interactions consistent newly measured binding energy ΛΛ6He. No significant enhancements above levels predictions observed. resulting upper limit for production cross section H range between and ΞN...
A double-$\Lambda$ hypernucleus, ${}_{\Lambda\Lambda}\mathrm{Be}$, was observed by the J-PARC E07 collaboration in nuclear emulsions tagged $(K^{-},K^{+})$ reaction. This event interpreted as a production and decay of $ {}_{\Lambda\Lambda}^{\;10}\mathrm{Be}$, ${}_{\Lambda\Lambda}^{\;11}\mathrm{Be}$, or ${}_{\Lambda\Lambda}^{\;12}\mathrm{Be}^{*}$ via $\Xi^{-}$ capture ${}^{16}\mathrm{O}$. By assuming atomic 3D state, binding energy two $\Lambda$ hyperons$\,$($B_{\Lambda\Lambda}$) these...
The differential cross sections of the Σ^{-}p→Λn reaction were measured accurately for Σ^{-} momentum (p_{Σ}) ranging from 470 to 650 MeV/c at J-PARC Hadron Experimental Facility. Precise angular information about was obtained first time by detecting approximately 100 events each step Δcosθ=0.1. show a slightly forward-peaking structure in regions. integrated -0.7≤cosθ≤1.0 as 22.5±0.68 [statistical error(stat.)] ±0.65 [systematic error(syst.)] mb and 15.8±0.83(stat)±0.52(syst)...
AMoRE (Advanced Mo based Rare process Experiment) collaboration is going to use calcium molybdate crystals as cryogenic scintillation detector in a search for neutrinoless DBD of 100Mo isotope. Simultaneous detection phonons and light will be used reject internal background. A FWHM resolution 0.2% the phonon channel has been achieved with 0.5 cm3 crystal. Several 40Ca100MoO4 (≈ kg) have developed from enriched depleted 40Ca materials. The yield these shown comparable reference CaMoO4...
We have observed a “|$K^{-}pp$|”-like structure in the |$d(\pi ^{+ },K^{+ })$| reaction at 1.69 GeV|$/c$|. In this reaction, |$\Lambda (1405)$| hyperon resonance is expected to be produced as doorway form |$K^{-}pp$| through ^{\ast }p\rightarrow K^{-}pp$| process. However, most of would escape from deuteron without secondary reactions. Therefore, coincidence high-momentum (|$>$|250 MeV|$/c$|) proton(s) large emission angles (|$39^\circ \lt \theta _{\rm lab.} 122^\circ$|) was requested...
We have carried out an experiment to search for a neutron-rich hypernucleus, $^6_{\Lambda}$H, by the $^6$Li($\pi^-,K^+$) reaction at $p_{\pi^-}$ =1.2 GeV/$c$. The obtained missing mass spectrum with estimated energy resolution of 3.2 MeV (FWHM) showed no peak structure corresponding $^6_{\Lambda}$H hypernucleus neither below nor above $^4_{\Lambda}$H$+2n$ particle decay threshold. An upper limit production cross section bound was be 1.2 nb/sr 90% confidence level.
We report the first observation of decay $\Lambda^{+}_{c} \rightarrow p K^{+} \pi^{-}$ using a 980 $\mathrm{fb^{-1}}$ data sample collected by Belle detector at KEKB asymmetric-energy $e^{+}e^{-}$ collider. This is doubly Cabibbo-suppressed charmed baryon to be observed. measure branching ratio this with respect its Cabibbo-favored counterpart $\mathcal{B}(\Lambda^{+}_{c} \pi^{-})/\mathcal{B}(\Lambda^{+}_{c} K^{-} \pi^{+})=(2.35\pm0.27\pm0.21)\times10^{-3}$, where uncertainties are...
A high statistics $\mathrm{\ensuremath{\Sigma}}p$ scattering experiment is performed at the J-PARC Hadron Experimental Facility. Momentum-tagged ${\mathrm{\ensuremath{\Sigma}}}^{\ensuremath{-}}\mathrm{s}$ running in a liquid hydrogen target are accumulated by detecting ${\ensuremath{\pi}}^{\ensuremath{-}}p\ensuremath{\rightarrow}{K}^{+}{\mathrm{\ensuremath{\Sigma}}}^{\ensuremath{-}}$ reaction with intensity ${\ensuremath{\pi}}^{\ensuremath{-}}$ beam of 20 M/spill. The differential cross...