Publications (45)
Observational detection of eight mutual eclipses and occultations between the satellites of Uranus
A. A. Christou, F. Lewis, P. Roche +13
We carried out observations, with five different instruments ranging in aperture from 0.4m to 10m, of the satellites of Uranus during that planet's 2007 Equinox. Our observations c…
XMM-Newton observation of the Lockman Hole; I. The X-ray Data
G. Hasinger, B. Altieri, M. Arnaud +25
We report on the first deep X-ray survey with the XMM-Newton observatory during the performance verification phase. The field of the Lockman Hole, one of the best studied sky areas…
Giant dielectric permittivity in Nb-doped rutile crystals
D. Nuzhnyy, V. Bovtun, J. Petzelt +13
Dielectric properties of Nb-doped (~1.5 at%) rutile single crystals were studied in the 10-300 K temperature range (at frequencies below the MHz range down to 0.3 K) in a broad fre…
Anisotropic Decay Dynamics of Photoexcited Aligned Carbon Nanotube Bundles
Y. Hashimoto, Y. Murakami, S. Maruyama +1
We have performed polarization-dependent ultrafast pump-probe spectroscopy of a film of aligned single-walled carbon nanotube bundles. By taking into account imperfect nanotube ali…
Density-constraint Time-dependent Hartree-Fock-Bogoliubov method
G. Scamps, Y. Hashimoto
Background: The Density-constraint Time-dependent Hartree-Fock method is currently the tool of choice to predict fusion cross-sections. However, it does not include pairing correla…
Nuclear collective tunneling transitions between Hartree states deformed in quadrupole symmetry
M. Maruyama, T. Kohmura, Y. Hashimoto
In a nucleus which has two Hartree states deformed in quadrupole symmetry, i.e., prolate state and oblate state, the nuclear residual interaction derived in the present theory beyo…
Analyzing power in elastic scattering of 6He from polarized proton target at 71 MeV/nucleon
S. Sakaguchi, Y. Iseri, T. Uesaka +33
The vector analyzing power has been measured for the elastic scattering of neutron-rich 6He from polarized protons at 71 MeV/nucleon making use of a newly constructed solid polariz…
Analyzing power for the proton elastic scattering from neutron-rich 6He nucleus
T. Uesaka, S. Sakaguchi, Y. Iseri +33
Vector analyzing power for the proton-6He elastic scattering at 71 MeV/nucleon has been measured for the first time, with a newly developed polarized proton solid target working at…
Effective Potential Study of the Chiral Phase Transition in a QCD-like Theory
Y. Hashimoto, Y. Tsue, H. Fujii
We construct the effective potential for a QCD-like theory using the auxiliary field method. The chiral phase transition exhibited by the model at finite temperature and the quark…
The metallicity extremes of the Sagittarius dSph using SALT spectroscopy of PNe
A. Kniazev, A. Zijlstra, E. Grebel +10
In this work we present the first spectroscopic results obtained with the Southern African Large Telescope (SALT) telescope during its perfomance-verification phase. We find that t…
Coherent manipulation of magnetization precession in ferromagnetic semiconductor (Ga,Mn)As with successive optical pumping
Y. Hashimoto, H. Munekata
We report dynamic control of magnetization precession by light alone. A ferromagnetic (Ga,Mn)As epilayer was used for experiments. Amplitude of precession was modulated to a large…
Dynamic nuclear polarization and Knight shift measurements in a breakdown regime of integer quantum Hall effect
M. Kawamura, H. Takahashi, S. Masubuchi +4
Nuclear spins are polarized electrically in a breakdown regime of an odd-integer quantum Hall effect (QHE). Electron excitation to the upper Landau subband with the opposite spin p…
Room temperature and low-field resonant enhancement of spin Seebeck effect in partially compensated magnets
R. Ramos, T. Hioki, Y. Hashimoto +7
Resonant enhancement of spin Seebeck effect (SSE) due to phonons was recently discovered in Y3Fe5O12 (YIG). This effect is explained by hybridization between the magnon and phonon…
One-neutron knockout reaction of 17C on a hydrogen target at 70 MeV/nucleon
Y. Satou, J. W. Hwang, S. Kim +29
First experimental evidence of the population of the first 2- state in 16C above the neutron threshold is obtained by neutron knockout from 17C on a hydrogen target. The invariant…
Landau Potential Study of the Chiral Phase Transition in a QCD-Like Theory
Y. Tsue, H. Fujii, Y. Hashimoto
We investigate the chiral phase transition of a QCD-like theory, based the shape change of the effective potential near the critical point. The potential is constructed with the au…
Ultrahigh-Field Hole Cyclotron Resonance Absorption in InMnAs Films
Y. H. Matsuda, G. A. Khodaparas, M. A. Zudov +10
We have carried out an ultrahigh-field cyclotron resonance study of p-type In1-xMnxAs films, with Mn composition x ranging from 0% to 2.5%, grown on GaAs by low-temperature molecul…
A numerical method of solving time-dependent Hartree-Fock-Bogoliubov equation with Gogny interaction
Y. Hashimoto, K. Nodeki
A numerical method to solve time-dependent Hartree-Fock-Bogoliubov equation is proposed to treat the case with Gogny effective interaction. To check the feasibility of the method,…
The polar ring galaxy AM1934-563 revisited
N. Brosch, A. Kniazev, D. Buckley +8
We report long-slit spectroscopic observations of the dust-lane polar-ring galaxy AM1934-563 obtained with the Southern African Large Telescope (SALT) during its performance-verifi…
Photo-induced precession of magnetization in ferromagnetic (Ga,Mn)As
Y. Hashimoto, H. Munekata
Precession of magnetization induced by pulsed optical excitation is observed in a ferromagnetic semiconductor (Ga,Mn)As by time-resolved magneto-optical measurements. It appears as…
The Hyper Suprime-Cam SSP Survey: Overview and Survey Design
H. Aihara, N. Arimoto, R. Armstrong +139
Hyper Suprime-Cam (HSC) is a wide-field imaging camera on the prime focus of the 8.2m Subaru telescope on the summit of Maunakea in Hawaii. A team of scientists from Japan, Taiwan…
The XMM-Newton Serendipitous Survey V. Optical identification of the XMM-Newton Medium sensitivity Survey (XMS)
X. Barcons, F. J. Carrera, M. T. Ceballos +53
We present the XMM-Newton Medium sensitivity Survey (XMS), including a total of 318 X-ray sources found among the serendipitous content of 25 XMM-Newton target fields. The XMS comp…
Experimental Limit to Interstellar 244Pu Abundance
M. Paul, A. Valenta, I. Ahmad +8
Short-lived nuclides, now extinct in the solar system, are expected to be present in the interstellar medium (ISM). Grains of ISM origin were recently discovered in the inner solar…
An extreme EXO: a type 2 QSO at z=1.87
A. Del Moro, M. G. Watson, S. Mateos +6
We aim to understand the multi-wavelength properties of 2XMM J123204+215255, the source with the most extreme X-ray-to-optical flux ratio amongst a sample of bright X-ray selected…
The Environment of ``E+A'' Galaxies
A. I. Zabludoff, D. Zaritsky, H. Lin +5
The violent star formation history of ``E+A'' galaxies and their detection almost exclusively in distant clusters is frequently used to link them to the ``Butcher-Oemler effect'' a…
Unbound excited states in 19,17C
Y. Satou, T. Nakamura, N. Fukuda +25
The neutron-rich carbon isotopes 19,17C have been investigated via proton inelastic scattering on a liquid hydrogen target at 70 MeV/nucleon. The invariant mass method in inverse k…
Adaptive optics imaging and optical spectroscopy of a multiple merger in a luminous infrared galaxy
P. Vaisanen, S. Mattila, A. Kniazev +16
(abridged) We present near-infrared (NIR) adaptive optics imaging obtained with VLT/NACO and optical spectroscopy from the Southern African Large Telescope (SALT) of a luminous inf…
Construction of KAGRA: an Underground Gravitational Wave Observatory
T. Akutsu, M. Ando, S. Araki +222
Major construction and initial-phase operation of a second-generation gravitational-wave detector KAGRA has been completed. The entire 3-km detector is installed underground in a m…
[O III] and X-ray Properties of a Complete Sample of Hard X-ray Selected AGNs in the Local Universe
Y. Ueda, Y. Hashimoto, K. Ichikawa +11
We study the correlation between the [O III] and X-ray luminosities of local Active Galactic Nuclei (AGNs), using a complete, hard X-ray ( keV) selected sample in the…
Self-shielding effect of a single phase liquid xenon detector for direct dark matter search
A. Minamino, K. Abe, Y. Ashie +41
Liquid xenon is a suitable material for a dark matter search. For future large scale experiments, single phase detectors are attractive due to their simple configuration and scalab…
14Be(p,n)14B reaction at 69 MeV in inverse kinematics
Y. Satou, T. Nakamura, Y. Kondo +25
A Gamow-Teller (GT) transition from the drip-line nucleus 14Be to 14B was studied via the (p,n) reaction in inverse kinematics using a secondary 14Be beam at 69 MeV/nucleon. The in…
The X-ray CCD camera of the MAXI Experiment on the ISS/JEM
E. Miyata, H. Tsunemi, H. Ogata +16
MAXI, Monitor of All-sky X-ray Image, is the X-ray observatory on the Japanese experimental module (JEM) Exposed Facility (EF) on the International Space Station (ISS). MAXI is a s…
Photo-induced demagnetization and polaron binding energy increase observed by mid-infrared pump-probe spectroscopy in ferromagnetic GaMnAs
E. Kojima, J. B. Heroux, R. Shimano +4
Time-resolved transmittance measurements performed on GaMnAs in the vicinity of the Mn-induced mid-infrared absorption band are presented. Upon photo-excitation,…
Propagating Coherent Acoustic Phonon Wavepackets in InMnAs/GaSb
J. Wang, Y. Hashimoto, J. Kono +4
We observe pronounced oscillations in the differential reflectivity of a ferromagnetic InMnAs/GaSb heterostructure using two-color pump-probe spectroscopy. Although originally thou…
OGLE-2008-BLG-510: first automated real-time detection of a weak microlensing anomaly - brown dwarf or stellar binary?
V. Bozza, M. Dominik, N. J. Rattenbury +103
The microlensing event OGLE-2008-BLG-510 is characterised by an evident asymmetric shape of the peak, promptly detected by the ARTEMiS system in real time. The skewness of the ligh…
Mixed Representation RPA Calculation for Octupole Excitations on Superdeformed Sates in the 40Ca and Neutron-Rich Sulfur Regions
T. Inakura, H. Imagawa, Y. Hashimoto +3
By means of the mixed representation RPA based on the Skyrme-Hartree-Fock mean field, we investigate low-frequency octupole excitations built on the superdeformed (SD) states in th…
Observation of the spin-charge thermal isolation of ferromagnetic Ga_{0.94}Mn_{0.06}As by time-resolved magneto-optical measurement
E. Kojima, R. Shimano, Y. Hashimoto +3
The dynamics of magnetization under femtosecond optical excitation is studied in a ferromagnetic semiconductor Ga_{0.94}Mn_{0.06}As with a time-resolved magneto-optical Kerr effect…
Groups of Galaxies in the Las Campanas Redshift Survey
D. L. Tucker, Y. Hashimoto, R. P. Kirshner +5
A "friends-of-friends" percolation algorithm has been used to extract a catalogue of drho/rho = 80 density enhancements (groups) from the six slices of the Las Campanas Redshift Su…
Discovery of the first symbiotic star in NGC6822
A. Kniazev, P. Vaisanen, P. A. Whitelock +10
We report the discovery of the first symbiotic star (V=21.6, K_S=15.8 mag) in the Local Group dwarf irregular galaxy NGC6822. This star was identified during a spectral survey of H…
Electrical coherent control of nuclear spins in a breakdown regime of quantum Hall effect
H. Takahashi, M. Kawamura, S. Masubuchi +4
Using a conventional Hall-bar geometry with a micro-metal strip on top of the surface, we demonstrate an electrical coherent control of nuclear spins in an AlGaAs/GaAs semiconducto…
Loose Groups of Galaxies in the Las Campanas Redshift Survey
D. L. Tucker, A. Oemler, Y. Hashimoto +6
A ``friends-of-friends'' percolation algorithm has been used to extract a catalogue of dn/n = 80 density enhancements (groups) from the six slices of the Las Campanas Redshift Surv…
Macrospin Dynamics in Antiferromagnets Triggered by Sub-20 femtosecond Injection of Nanomagnons
D. Bossini, S. Dal Conte, Y. Hashimoto +5
The understanding of how the sub-nanoscale exchange interaction evolves in macroscale correlations and ordered phases of matter, such as magnetism and superconductivity, requires t…
Adiabatic measurements of magneto-caloric effects in pulsed high magnetic fields up to 55 T
T. Kihara, Y. Kohama, Y. Hashimoto +2
Magneto-caloric effects (MCEs) measurement system in adiabatic condition is proposed to investigate the thermodynamic properties in pulsed magnetic fields up to 55 T. With taking t…
Conservation Properties in the Time-Dependent Hartree Fock Theory
Lu Guo, J. A. Maruhn, P. -G. Reinhard +1
We discuss the conservation of angular momentum in nuclear time-dependent Hartree-Fock calculations for a numerical representation of wave functions and potentials on a three-dimen…
Applications of the Ashtekar gravity to four dimensional hyperkähler geometry and Yang-Mills Instantons
Y. Hashimoto, Y. Yasui, S. Miyagi +1
The Ashtekar-Mason-Newman equations are used to construct the hyperkähler metrics on four dimensional manifolds. These equations are closely related to anti self-dual Yang-Mills e…
Vibration isolation system with a compact damping system for power recycling mirrors of KAGRA
Y. Akiyama, T. Akutsu, M. Ando +169
A vibration isolation system called Type-Bp system used for power recycling mirrors has been developed for KAGRA, the interferometric gravitational-wave observatory in Japan. A sus…