M. Honda

The University of Tokyo, Tokyo, Tokyo-to, Japan

Are you M. Honda?

Claim your profile

Publications (166)269.55 Total impact

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, we extend the calculation of the atmospheric neutrino flux~\cite{hkkm2004,hkkms2006,hkkm2011} to the sites in polar and tropical regions. In our earliest full 3D-calculation~\cite{hkkm2004}, we used DPMJET-III~\cite{dpm} for the hadronic interaction model above 5~GeV, and NUCRIN~\cite{nucrin} below 5~GeV. We modified DPMJET-III as in Ref.~\cite{hkkms2006} to reproduce the experimental muon spectra better, mainly using the data observed by BESS group~\cite{BESSTeVpHemu}. In a recent work~\cite{hkkm2011}, we introduced JAM interaction model for the low energy hadronic interactions. JAM is a nuclear interaction model developed with PHITS (Particle and Heavy-Ion Transport code System)~\cite{phits}. In Ref.~\cite{hkkm2011}, we could reproduce the observed muon flux at the low energies at balloon altitude with DPMJET-III above 32 GeV and JAM below that better than the combination of DPMJET-III above 5~GeV and NUCRIN below that. Besides the interaction model, we have also improved the calculation scheme according to the increase of available computational power, such as the "virtual detector correction" introduced in Ref.~\cite{hkkms2006} and the optimization of it in Ref.~\cite{hkkm2011}. The statistics of the Monte Carlo simulation is also improved at every step of the work.
  • [Show abstract] [Hide abstract]
    ABSTRACT: We present the calculation of the atmospheric neutrino fluxes for the neutrino experiments proposed at INO, South Pole and Pyhäsalmi. Neutrino fluxes have been obtained using ATMNC, a simulation code for cosmic ray in the atmosphere. Even using the same primary flux model and the interaction model, the calculated atmospheric neutrino fluxes are different for the different sites due to the geomagnetic field. The prediction of these fluxes in the present Letter would be quite useful in the experimental analysis.
    Physics Letters B 01/2013; 718(s 4–5):1375–1380. DOI:10.1016/j.physletb.2012.12.016 · 6.02 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We present the calculation of the atmospheric neutrino fluxes for the neutrino experiments proposed at INO, South Pole and Pyh\"asalmi. Neutrino fluxes have been obtained using ATMNC, a simulation code for cosmic ray in the atmosphere. Even using the same primary flux model and the interaction model, the calculated atmospheric neutrino fluxes are different for the different sites due to the geomagnetic field. The prediction of these fluxes in the present paper would be quite useful in the experimental analysis.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We present the calculation of the atmospheric neutrino fluxes with an interaction model named JAM, which is used in PHITS (Particle and Heavy-Ion Transport code System) [ K. Niita et al. Radiation Measurements 41 1080 (2006)]. The JAM interaction model agrees with the HARP experiment [ Astropart. Phys. 30 124 (2008)] a little better than DPMJET-III [S. Roesler, R. Engel, and J. Ranft, arXiv:hep-ph/0012252.]. After some modifications, it reproduces the muon flux below 1 GeV/c at balloon altitudes better than the modified DPMJET-III, which we used for the calculation of atmospheric neutrino flux in previous works [ T. Sanuki, M. Honda, T. Kajita, K. Kasahara and S. Midorikawa Phys. Rev. D 75 043005 (2007)][ M. Honda, T. Kajita, K. Kasahara, S. Midorikawa and T. Sanuki Phys. Rev. D 75 043006 (2007)]. Some improvements in the calculation of atmospheric neutrino flux are also reported.
    Physical review D: Particles and fields 06/2011; 83(12). DOI:10.1103/PhysRevD.83.123001 · 4.86 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: To shed light on the mechanism underlying the active morphogenesis of living cells in relation to the organization of internal cytoskeletal networks, the development of new methodologies to construct artificial cell models is crucial. Here, we describe the successful construction of cell-sized liposomes entrapping cytoskeletal proteins. We discuss experimental protocols to prepare giant liposomes encapsulating desired amounts of actin and cross-linking proteins including molecular motor proteins, such as fascin, alpha-actinin, filamin, myosin-I isolated from brush border (BBMI), and heavy meromyosin (HMM). Subfragment 1 (S-1) is also studied in comparison to HMM, where S-1 and HMM are single-headed and double-headed derivatives of conventional myosin (myosin-II), respectively. In the absence of cross-linking proteins, actin filaments (F-actin) are distributed homogeneously without any order within the liposomes. In contrast, when actin is encapsulated together with an actin-cross-linking protein, mesh structures emerge that are similar to those in living motile cells. Optical microscopic observations on the active morphological changes of the liposomes are reported.
    Methods in enzymology 01/2009; 464:31-53. DOI:10.1016/S0076-6879(09)64003-9 · 2.19 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We analyze the data of the gravitational microlensing survey carried out by the Microlensing Observations in Astrophysics (MOA) group during 2000 toward the Galactic bulge (GB). Our observations are designed to detect efficient high-magnification events with faint source stars and short-timescale events, by increasing the sampling rate up to ~6 times per night and using Difference Image Analysis (DIA). We detect 28 microlensing candidates in 12 GB fields corresponding to 16 deg2. We use Monte Carlo simulations to estimate our microlensing event detection efficiency, where we construct the I-band extinction map of our GB fields in order to find dereddened magnitudes. We find a systematic bias and large uncertainty in the measured value of the timescale tE,out in our simulations. They are associated with blending and unresolved sources, and are allowed for in our measurements. We compute an optical depth τ = 2.59 × 10-6 toward the GB for events with timescales 0.3 < tE < 200 days. We consider disk-disk lensing, and obtain an optical depth τbulge = 3.36 × 10-6[0.77/(1 - fdisk)] for the bulge component assuming a 23% stellar contribution from disk stars. These observed optical depths are consistent with previous measurements by the MACHO and OGLE groups, and still higher than those predicted by existing Galactic models. We present the timescale distribution of the observed events, and find there are no significant short events of a few days, in spite of our high detection efficiency for short-timescale events down to tE ~ 0.3 days. We find that half of all our detected events have high magnification (>10). These events are useful for studies of extrasolar planets.
    The Astrophysical Journal 12/2008; 591(1):204. DOI:10.1086/375212 · 6.28 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The atmospheric neutrino is still an important tool in the study of neutrino physics. The uncer-tainty of the predicted atmospheric neutrino flux is caused by the uncertainties in the physical assumptions and in the calculation scheme. We discuss them quantitatively, and present the works to reduce them. The uncertainty related to the hadronic interaction model was discussed before, therefore, we mainly study other uncertainty sources than the hadronic interaction model here.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Optical photometry and H I synthesis observations of the southern edge-on Sc/Sd galaxy IC 5249 are reported. The rotation curve rises linearly out to a radius of 7 kpc and then appears to flatten out at ~100 km s-1. The H I mass out to 24.5 kpc is ~6 × 109 M, or 10% of the total mass out to this radius. The color, central surface brightness, scale height, and scale length of the disk of IC 5249 are R - I ≈ 0.4, μ = 20.6 ± 0.1RC mag arcsec-2, 600 ± 40 pc, and 11 ± 2 kpc, respectively. Additional light to that predicted by an exponential disk is present at distances greater than 3 kpc from the disk. At 5 kpc the surface brightness is 27–28RC mag arcsec-2. The measured distribution of surface brightness is used to constrain the abundance of low-mass main-sequence stars in the halo of the galaxy. A halo made up entirely of main-sequence stars heavier than 0.13 M is excluded. We also find that less than 20% of the halo can be composed of main-sequence stars heavier than 0.30 M. Further observations are required to determine the rotation curve of IC 5249 to large radii and to determine precisely the abundance of low-mass main-sequence stars in the halo of the galaxy.
    The Astronomical Journal 12/2007; 118(1):261. DOI:10.1086/300907 · 4.05 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Using the ``modified DPMJET-III'' model explained in the previous paper, we calculate the atmospheric neutrino flux. The calculation scheme is almost the same as HKKM04 \cite{HKKM2004}, but the usage of the ``virtual detector'' is improved to reduce the error due to it. Then we study the uncertainty of the calculated atmospheric neutrino flux summarizing the uncertainties of individual components of the simulation. The uncertainty of $K$-production in the interaction model is estimated by modifying FLUKA'97 and Fritiof 7.02 so that they also reproduce the atmospheric muon flux data correctly, and the calculation of the atmospheric neutrino flux with those modified interaction models. The uncertainties of the flux ratio and zenith angle dependence of the atmospheric neutrino flux are also studied.
    Physical review D: Particles and fields 12/2006; 75(4). DOI:10.1103/PhysRevD.75.043006 · 4.86 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We have studied the hadronic interaction for the calculation of the atmospheric neutrino flux by summarizing the accurately measured atmospheric muon flux data and comparing with simulations. We find the atmospheric muon and neutrino fluxes respond to errors in the $\pi$-production of the hadronic interaction similarly, and compare the atmospheric muon flux calculated using the HKKM04 code with experimental measurements. The $\mu^++\mu^-$ data show good agreement in the 1$\sim$30 GeV/c range, but a large disagreement above 30 GeV/c. The the $\mu^+/\mu^-$ ratio shows sizable differences at lower and higher momenta for opposite directions. As the disagreements are considered to be due to assumptions in the hadronic interaction model, we try to improve it phenomenologically based on the quark parton model. The improved interaction model reproduces the observed muon flux data well. The calculation of the atmospheric neutrino flux will be reported in the following paper
    Physical review D: Particles and fields 12/2006; 75(4). DOI:10.1103/PhysRevD.75.043005 · 4.86 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Living cells develop their own characteristic shapes depending on their physiological functions, and their morphologies are based on the mechanical characteristics of the cytoskeleton and of membranes. To investigate the role of lipid membranes in morphogenesis, we constructed a simple system that can manipulate liposomes and measure the forces required to transform their shapes. Two polystyrene beads (1 microm in diameter) were encapsulated in giant liposomes and were manipulated using double-beam laser tweezers. Without any specific interaction between the lipid membrane and beads, mechanical forces could be applied to the liposome membrane from the inside. Spherical liposomes transformed into a lemon shape with increasing tension, and tubular membrane projections were subsequently generated in the tips at either end. This process is similar to the liposomal transformation caused by elongation of encapsulated cytoskeletons. In the elongation stage of lemon-shaped liposomes, the force required for the transformation became larger as the end-to-end length increased. Just before the tubular membrane was generated, the force reached the maximum strength (approximately 11 pN). However, immediately after the tubular membrane developed, the force suddenly decreased and was maintained at a constant strength (approximately 4 pN) that was independent of further tube elongation or shortening, even though there was no excess membrane reservoir as occurs in living cells. When the tube length was shortened to approximately 2 microm, the liposome reversed to a lemon shape and the force temporarily increased (to approximately 7 pN). These results indicate that the simple application of mechanical force is sufficient to form a protrusion in a membrane, that a critical force and length is needed to form and to maintain the protrusion, and suggest that the lipid bilayer itself has the ability to buffer the membrane tension.
    Journal of Molecular Biology 05/2005; 348(2):325-33. DOI:10.1016/j.jmb.2005.02.060 · 3.96 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Many types of myosin have been found and characterized to date, and already nearly 20 classes have been identified. However, these myosin motors can be classified more simply into two groups according to their head-structure, i.e. double- or single-headed myosins. Why do some myosin motors possess a double-headed structure? One obvious possible reason would be that the two heads improve the motor's processivity and sliding performance. Previously, to investigate the possibility that the double-headed myosins simultaneously interact with parallel arrayed two actin filaments in the presence of Mg-ATP, we developed an in vitro assay system using actin bundles formed by inert polymers. Using that system, we show here that skeletal muscle heavy meromyosin (HMM), a double-headed myosin derivative, but not subfragment-1 (S-1), a single-headed one, was able to contract or elongate actin bundles in a concentration-dependent manner. Similar elongation or contraction of actin bundles can also be induced by other double-headed myosin species isolated in the native state from Dictyostelium, from green algae Chara or from chicken brain. The results of this study confirm that double-headed myosin motors can induce sliding movements among neighboring actin filaments. The double-headed structure of myosins may also be important for generating tension or elongation in actin bundles or gels, and for organizing polarity-sorted actin networks, not just for improving their motor processivity or activity.
    Journal of Molecular Biology 09/2004; 341(2):467-76. DOI:10.1016/j.jmb.2004.06.019 · 3.96 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We have revised the calculation of the flux of atmospheric neutrinos based on a three-dimensional scheme with the realistic IGRF geomagnetic model. The primary flux model has been revised, based on the AMS and BESS observations, and the interaction model updated to DPMJET-III. With a fast simulation code and computer system, the statistical errors in the Monte Carlo study are negligible. We estimate the total uncertainty of the atmospheric neutrino flux prediction is reduced to &lsim;10 % below 10 GeV. The ``three-dimensional effects'' are found to be almost the same as the study with the dipole magnetic field, but the muon-curvature effect remains up to a few tens of GeV for horizontal directions. The uncertainty of the absolute normalization of the atmospheric neutrino is still large, above 10 GeV, due to the uncertainty of the primary cosmic ray flux above 100 GeV. However, the zenith angle variation is not affected by these uncertainties.
    Physical Review D 08/2004; 70(4). DOI:10.1103/PhysRevD.70.043008 · 4.86 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: More than 4000 stars observed in both MOA and DENIS projects showing periodic or quasi periodic light curves are studied. Almost all Mira stars are located on the classical period luminosity relation, and the multiplicity of the period luminosity relation is confirmed for small amplitude stars. The color magnitude diagrams based on the MOA red band, Rm, and KS constructed for the sequences, form a single strip with small successive shifts.
    04/2004; 310:332.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Data for 4.4 million stars from the Microlensing Observations in Astrophysics (MOA) project are compared with the near-infrared data of the Deep Near Infrared Southern Sky Survey (DENIS). More than 4000 stars observed in both projects show a quite periodic light curve. Among them, a number of stars are likely eclipsing variables, and the others seem to be pulsating stars. The KS magnitudes of these red variables are in the range 10–12.5 but a minor clump at KS≈ 12.2 mag is also found. The multiplicity of the period–luminosity relation is confirmed, but most of the regular, large-amplitude variables are found on the relation established for the Mira stars. We study the properties of the variables on the colour–magnitude diagram constructed with the MOA red band Rm and KS of DENIS. Multiplicity of the period–luminosity relation is briefly discussed in relation to the excitation mechanism of red pulsating variables.
    Monthly Notices of the Royal Astronomical Society 02/2004; 348(4):1120 - 1134. DOI:10.1111/j.1365-2966.2004.07413.x · 5.23 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Precise knowledge of the hadronic interaction between primary cosmic rays and atmospheric nuclei is very important and fundamental to study atmospheric neutrinos and their oscillations. We studied hadronic interaction models using the data of primary and secondary cosmic rays observed by BESS experiments. By comparing the observed spectra with the ones calculated by several interaction models, we found DPMJET-III is most favored among them.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The light curves for three eclipsing binaries in the Magellanic Clouds have been obtained using CCD uVJIC photometry. One target in the LMC, MACHO*05:36:48.769:17:00, is an eccentric system, e = 0.20, with a period of 3.853534�0.000005 d. Initial solutions indicate a primary component in the range Te�;1 = 20,00035,000K and the secondary Te�;2 10002000K cooler than the primary, with inclinations ranging i = 84.2� 86.0�. Two targets in the SMC, MOA J005018.4723855 and MOA J005623.5722123, have periods of 1.8399�0.0004 and 2.3199�0.0003 days respectively. Both have circular orbits with the former being a semi-detached system.
    Revista mexicana de astronomía y astrofísica 01/2004; 21:116-120. · 1.07 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Se han obtenido curvas de luz para tres binarias eclipsantes en las Nubes de Magallanes mediante fotometra CCD uVJIC. Uno de los objetos en la GNM, MACHO*05:36:48.7
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We present here a detailed 3-dimensional calculation of the atmospheric neutrino flux in the realistic geomagnetic field. We intro duce no simplification based on the symmetry, but a faster computer system with a faster simulation code. The results here generally confirm previous studies. However, we found some differences due to the difference of geomagnetic field model.

Publication Stats

3k Citations
269.55 Total Impact Points

Institutions

  • 1986–2011
    • The University of Tokyo
      • Institute for Cosmic Ray Research
      Tokyo, Tokyo-to, Japan
  • 1998–2009
    • Nagoya University
      • • Department of Biological Science
      • • Division of Cell Science
      • • Graduate School of Science
      Nagoya, Aichi, Japan
    • Kyoto University
      • Department of Physics II
      Kyoto, Kyoto-fu, Japan
  • 1990–1998
    • Tokyo Institute of Technology
      • Department of Physics
      Tokyo, Tokyo-to, Japan
    • Tokyo Gakugei University
      Koganei, Tōkyō, Japan
  • 1993–1996
    • Chiba University Hospital
      Tiba, Chiba, Japan
    • Tata Institute of Fundamental Research
      Mumbai, Maharashtra, India
  • 1995
    • Nara Medical University
      Kashihara, Nara, Japan
  • 1988
    • Kanagawa University
      Yokohama, Kanagawa, Japan