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Arifi, A. J.*; Nagahiro, Hideko*; Hosaka, Atsushi; Tanida, Kiyoshi
Physical Review D, 101(11), p.111502_1 - 111502_5, 2020/06
Times Cited Count：1 Percentile：40.35(Astronomy & Astrophysics)
and determination of its spin-parityArifi, A. J.*; Nagahiro, Hideko*; Hosaka, Atsushi; Tanida, Kiyoshi
Physical Review D, 101(9), p.094023_1 - 094023_17, 2020/05
Times Cited Count：1 Percentile：40.35(Astronomy & Astrophysics)
pentaquark states predicted by a quark modelMeng, Q.*; Hiyama, Emiko*; Can, K. U.*; Gubler, P.; Oka, Makoto; Hosaka, Atsushi; Zong, H.*
Physics Letters B, 798, p.135028_1 - 135028_8, 2019/11
Times Cited Count：0
pentaquark states predicted by a quark modelMeng, Q.*; Hiyama, Emiko; Can, K. U.*; Gubler, P.; Oka, Makoto; Hosaka, Atsushi; Zong, H.*
Physics Letters B, 798, p.135028_1 - 135028_8, 2019/11
Times Cited Count：3 Percentile：41(Astronomy & Astrophysics)Wakayama, Masayuki*; Hosaka, Atsushi
Physics Letters B, 795, p.548 - 553, 2019/08
Times Cited Count：2 Percentile：41(Astronomy & Astrophysics)Shim, S.-I.*; Hosaka, Atsushi; Kim, H.-C.*
Physics Letters B, 795, p.438 - 445, 2019/08
Times Cited Count：1 Percentile：63.02(Astronomy & Astrophysics)
via 
Nam, S.-I.*; Hosaka, Atsushi
Physical Review C, 100(1), p.015205_1 - 015205_10, 2019/07
Times Cited Count：0 Percentile：100(Physics, Nuclear)Liu, M.-Z.*; Pan, Y.-W.*; Peng, F.-Z.*; S
nchez-Snchez, M.*; Geng, L.-S.*; Hosaka, Atsushi; Valderrama, M. P.*
Physical Review Letters, 122(24), p.242001_1 - 242001_5, 2019/06
Times Cited Count：68 Percentile：0.22(Physics, Multidisciplinary)
and 
as 
-wave bottom baryons of 
Cui, E.-L.*; Yang, H.-M.*; Chen, H.-X.*; Hosaka, Atsushi
Physical Review D, 99(9), p.094021_1 - 094021_15, 2019/05
Times Cited Count：16 Percentile：4.51(Astronomy & Astrophysics)Hiyama, Emiko; Hosaka, Atsushi; Oka, Makoto; Richard, J.-M.*
Physical Review C, 98(4), p.045208_1 - 045208_8, 2018/10
Times Cited Count：12 Percentile：9.72(Physics, Nuclear)A quark model, which reproduces the ground-state mesons and baryons, i.e., the threshold energies, is applied to the 
configurations, where 
is a light quark and 
the charmed quark. In the calculation, several open channels are explicitly included such as 
, 
, 
, etc. To distinguish genuine resonances and estimate their width, we employ Gaussian Expansion Method supplemented by the real scalingmethod (stabilization). No resonance is found at the energies of the 
and 
pentaquarks. On the other hand, there is a sharp resonant state at 4690 MeV with 
state and another one at 4920 MeV with 
state, which have a compact structure.
Nagahiro, Hideko*; Yasui, Shigehiro*; Hosaka, Atsushi; Oka, Makoto; Noumi, Hiroyuki*; Noumi, Hiroyuki*
Physical Review D, 95(1), p.014023_1 - 014023_20, 2017/01
Times Cited Count：33 Percentile：6.26(Astronomy & Astrophysics)We investigate the decays of the charmed baryons aiming at the systematic understanding of hadron internal structures based on the quark model by paying attention to heavy quark symmetry. We evaluate the decay widths from the one pion emission for the known excited states, 
, 
, 
, 
and 
, as well as for the ground states 
and 
. The calculated decay widths are in good agreement with the experimental data, and several important predictions for higher excited 
baryons are given. We also find that the axial-vector type coupling of the pion to the light quarks is essential, which is expected from chiral symmetry, to reproduce the decay widths especially of the low lying baryons. We emphasize the importance of the branching ratios of 
for the study of the nature of higher excited baryons.
Yoshida, Tetsuya*; Hiyama, Emiko*; Hosaka, Atsushi*; Oka, Makoto; Sadato, Katsunori*
Physical Review D, 92(11), p.114029_1 - 114029_19, 2015/12
Times Cited Count：93 Percentile：1.43(Astronomy & Astrophysics)Single- and double-heavy baryons are studied in the constituent quark model. The model Hamiltonian is chosen as a standard one with two exceptions: (1) the color-Coulomb term depends on quark masses and (2) an antisymmetric 
(spin-orbit) force is introduced. Model parameters are fixed by the strange baryon spectra, 
and 
baryons. The masses of the observed charmed and bottomed baryons are, then, fairly well reproduced. Our focus is on the low-lying negative-parity states, in which the heavy baryons show specific excitation modes reflecting the mass differences of heavy and light quarks. By changing quark masses from the SU(3) limit to the strange quark mass, and, further, to the charm and bottom quark masses, we demonstrate that the spectra change from the SU(3) symmetry patterns to the heavy-quark-symmetry ones.
Itakura, Ryuji; Hosaka, Koichi*; Yokoyama, Atsushi; Ikuta, Tomoya*; Kannari, Fumihiko*; Yamanouchi, Kaoru*
Progress in Ultrafast Intense Laser Science XI; Springer Series in Chemical Physics, Vol.109, p.23 - 42, 2015/00
We investigate the multichannel dissociative ionization of ethanol in intense laser fields by the photoelectron-photoion coincidence momentum imaging and identify separately the ionization and subsequent electronic excitation in ethanol. From the energy correlation between a photoelectron and a fragment ion, we reveal the amount of the internal energy gained by ethanol cations from the laser field varies depending on the respective ionization and electronic excitation pathways.
Hosaka, Koichi*; Yokoyama, Atsushi; Yamanouchi, Kaoru*; Itakura, Ryuji
Journal of Chemical Physics, 138(20), p.204301_1 - 204301_9, 2013/05
Times Cited Count：9 Percentile：59.62(Chemistry, Physical)Dissociative ionization of ethanol (C
H
OH) induced by an intense near-infrared laser pulse are investigated using photoelectron-photoion coincidence method. It is shown that both the electronic ground state and the first electronically excited state of CHOH
are produced at the moment of photoelectron emission. From the observed correlation between the electronic states of CHOH prepared at the moment of photoelectron emission and the kinetic energy release of the fragment ions, it is revealed that CHOH prepared in the electronic ground state at the photoelectron emission gains larger internal energy in the end than that prepared in the electronically excited state. The averaged internal energy of CHOH just before the dissociation is found to increase when the laser field intensity increases from 9 to 23 TW/cm
. And when the laser pulse duration increases from 35 to 800 fs.
Ikuta, Tomoya*; Hosaka, Koichi*; Akagi, Hiroshi; Yokoyama, Atsushi; Yamanouchi, Kaoru*; Kannari, Fumihiko*; Itakura, Ryuji
Journal of Physics B; Atomic, Molecular and Optical Physics, 44(19), p.191002_1 - 191002_5, 2011/10
Times Cited Count：7 Percentile：58.63(Optics)Ionization and subsequent electronic excitation occurring within the same laser pulse (400 nm, 96 fs, 1.3
18 TW/cm
) are separately investigated by measuring in coincidence an electron and a product ion produced from CHOH. We reveal that the nascent population in the electronically excited CHOH prepared by the ionization decreases as the laser intensity increases, while the subsequent electronic excitation is enhanced through the resonant electronic transitions. Ionization and electronic excitation mechanisms are described based on the electronic state distributions of CHOH.
Hosaka, Koichi; Itakura, Ryuji; Yokoyama, Keiichi; Yamanouchi, Kaoru*; Yokoyama, Atsushi
Chemical Physics Letters, 475(1-3), p.19 - 23, 2009/06
Times Cited Count：10 Percentile：63.45(Chemistry, Physical)In intense laser fields, molecules are decomposed into fragments through a number of competing dissociative ionization pathways. We investigate the dissociative ionization dynamics of ethanol in intense laser fields with photoelectron-photoion coincidence momentum imaging. The channel-specific photoelectron spectra reveal the electronic states prepared just after ionization, depending both on the decomposition pathways and on the temporal profile of laser pulses.
Hosaka, Koichi; Itakura, Ryuji; Yokoyama, Keiichi; Yamanouchi, Kaoru*; Yokoyama, Atsushi
no journal, ,
When molecules are exposed to intense laser fields, dissociative ionization is efficiently induced and several decomposition pathways competes. The present study aims at revealing the correlation between the electronic states just after ionization and the following dissociation process. The photoelectron-photoion coincidence momentum imaging (PEPICO-MI) technique enables us to detect photoelectrons and photoions produced in a single event simultaneously. We applied PEPICO-MI to dissociative ionization of ethanol (CHOH), whose branching ratio varies as a function of the laser pulse duration. When ethanol molecules are irradiated with a short laser pulse, photoelectron images strongly depend on the correlated product ions.
Hosaka, Koichi; Itakura, Ryuji; Yokoyama, Keiichi; Yamanouchi, Kaoru*; Yokoyama, Atsushi
no journal, ,
In intense laser fields, molecules are decomposed into fragments through a number of competing dissociative ionization pathways. We investigate the dissociative ionization dynamics of ethanol in intense laser fields with photoelectron-photoion coincidence momentum imaging. The channel-specific photoelectron spectra reveal the electronic states prepared just after ionization, depending both on the decomposition pathways and on the temporal profile of laser pulses.
Hosaka, Koichi; Itakura, Ryuji; Yokoyama, Keiichi; Yamanouchi, Kaoru*; Yokoyama, Atsushi
no journal, ,
In intense laser fields, molecules are decomposed into fragments through a number of competing dissociative ionization pathways. We investigate the dissociative ionization dynamics of ethanol in intense laser fields with photoelectron-photoion coincidence momentum imaging. The channel-specific photoelectron spectra reveal the electronic states prepared just after ionization, depending both on the decomposition pathways and on the temporal profile of laser pulses.
Hosaka, Koichi; Itakura, Ryuji; Yokoyama, Keiichi; Yamanouchi, Kaoru*; Yokoyama, Atsushi
no journal, ,
In intense laser fields, molecules are decomposed into fragments through a number of competing dissociative ionization pathways. We investigate the dissociative ionization dynamics of ethanol in intense laser fields with photoelectron-photoion coincidence momentum imaging. The channel-specific photoelectron spectra reveal the electronic states prepared just afterionization, depending both on the decomposition pathways and on the temporal profile of laserpulses.
