Daisuke Yonetoku

Kanazawa University, Kanazawa, Ishikawa, Japan

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Publications (121)168.07 Total impact

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    ABSTRACT: The Extreme Universe Space Observatory on board the Japanese Experiment Module of the International Space Station, JEM-EUSO, is being designed to search from space ultra-high energy cosmic rays. These are charged particles with energies from a few 1019 eV to beyond 1020 eV, at the very end of the known cosmic ray energy spectrum. JEM-EUSO will also search for extreme energy neutrinos, photons, and exotic particles, providing a unique opportunity to explore largely unknown phenomena in our Universe. The mission, principally based on a wide field of view (60 degrees) near-UV telescope with a diameter of ∼ 2.5 m, will monitor the earth’s atmosphere at night, pioneering the observation from space of the ultraviolet tracks (290-430 nm) associated with giant extensive air showers produced by ultra-high energy primaries propagating in the earth’s atmosphere. Observing from an orbital altitude of ∼ 400 km, the mission is expected to reach an instantaneous geometrical aperture of A g e o ≥ 2 × 105 km2 sr with an estimated duty cycle of ∼ 20 %. Such a geometrical aperture allows unprecedented exposures, significantly larger than can be obtained with ground-based experiments. In this paper we briefly review the history of space-based search for ultra-high energy cosmic rays. We then introduce the special issue of Experimental Astronomy devoted to the various aspects of such a challenging enterprise. We also summarise the activities of the on-going JEM-EUSO program.
    Full-text · Article · Nov 2015 · Experimental Astronomy
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    ABSTRACT: Space-based detectors for the study of extreme energy cosmic rays (EECR) are being prepared as a promising new method for detecting highest energy cosmic rays. A pioneering space device – the “tracking ultraviolet set-up” (TUS) – is in the last stage of its construction and testing. The TUS detector will collect preliminary data on EECR in the conditions of a space environment, which will be extremely useful for planning the major JEM-EUSO detector operation.
    Full-text · Article · Nov 2015 · Experimental Astronomy
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    ABSTRACT: EUSO-Balloon is a pathfinder for JEM-EUSO, the Extreme Universe Space Observatory which is to be hosted on-board the International Space Station. As JEM-EUSO is designed to observe Ultra-High Energy Cosmic Rays (UHECR)-induced Extensive Air Showers (EAS) by detecting their ultraviolet light tracks “from above”, EUSO-Balloon is a nadir-pointing UV telescope too. With its Fresnel Optics and Photo-Detector Module, the instrument monitors a 50 km2 ground surface area in a wavelength band of 290–430 nm, collecting series of images at a rate of 400,000 frames/sec. The objectives of the balloon demonstrator are threefold: a) perform a full end-to-end test of a JEM-EUSO prototype consisting of all the main subsystems of the space experiment, b) measure the effective terrestrial UV background, with a spatial and temporal resolution relevant for JEM-EUSO. c) detect tracks of ultraviolet light from near space for the first time. The latter is a milestone in the development of UHECR science, paving the way for any future space-based UHECR observatory. On August 25, 2014, EUSO-Balloon was launched from Timmins Stratospheric Balloon Base (Ontario, Canada) by the balloon division of the French Space Agency CNES. From a float altitude of 38 km, the instrument operated during the entire astronomical night, observing UV-light from a variety of ground-covers and from hundreds of simulated EASs, produced by flashers and a laser during a two-hour helicopter under-flight.
    Full-text · Article · Aug 2015 · Experimental Astronomy
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    ABSTRACT: Ultra high energy photons and neutrinos are carriers of very important astrophysical information. They may be produced at the sites of cosmic ray acceleration or during the propagation of the cosmic rays in the intergalactic medium. In contrast to charged cosmic rays, photon and neutrino arrival directions point to the production site because they are not deflected by the magnetic fields of the Galaxy or the intergalactic medium. In this work we study the characteristics of the longitudinal development of showers initiated by photons and neutrinos at the highest energies. These studies are relevant for development of techniques for neutrino and photon identification by the JEM-EUSO telescope. In particular, we study the possibility of observing the multi-peak structure of very deep horizontal neutrino showers with JEM-EUSO. We also discuss the possibility to determine the flavor content of the incident neutrino flux by taking advantage of the different characteristics of the longitudinal profiles generated by different type of neutrinos. This is of grate importance for the study of the fundamental properties of neutrinos at the highest energies. Regarding photons, we discuss the detectability of the cosmogenic component by JEM-EUSO and also estimate the expected upper limits on the photon fraction which can be obtained from the future JEM-EUSO data for the case in which there are no photons in the samples.
    Full-text · Article · Jul 2015 · Experimental Astronomy
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    ABSTRACT: Mounted on the International Space Station(ISS), the Extreme Universe Space Observatory, on-board the Japanese Experimental Module (JEM-EUSO), relies on the well established fluorescence technique to observe Extensive Air Showers (EAS) developing in the earth’s atmosphere. Focusing on the detection of Ultra High Energy Cosmic Rays (UHECR) in the decade of 1020eV, JEM-EUSO will face new challenges by applying this technique from space. The EUSO Simulation and Analysis Framework (ESAF) has been developed in this context to provide a full end-to-end simulation frame, and assess the overall performance of the detector. Within ESAF, angular reconstruction can be separated into two conceptually different steps. The first step is pattern recognition, or filtering, of the signal to separate it from the background. The second step is to perform different types of fitting in order to search for the relevant geometrical parameters that best describe the previously selected signal. In this paper, we discuss some of the techniques we have implemented in ESAF to perform the geometrical reconstruction of EAS seen by JEM-EUSO. We also conduct thorough tests to assess the performances of these techniques in conditions which are relevant to the scope of the JEM-EUSO mission. We conclude by showing the expected angular resolution in the energy range that JEM-EUSO is expected to observe.
    Full-text · Article · Jul 2015 · Experimental Astronomy
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    ABSTRACT: We have observed the prompt emission of GRB100418A, from its beginning by the MAXI/SSC (0.7-7 keV) on board the International Space Station followed by the Swift/XRT (0.3-10 keV) observation. The light curve can be fitted by a combination of a power law component and an exponential component (decay constant is $31.6\pm 1.6$). The X-ray spectrum is well expressed by the Band function with $E_{\rm p}\leq$8.3 keV. This is the brightest GRB showing a very low value of $E_{\rm p}$. It is also consistent with the Yonetoku-relation ($E_{\rm p}$-$L_{\rm p}$) while it is not clear with the Amati-relation ($E_{\rm p}$-$E_{\rm iso}$).
    Preview · Article · Jul 2015 · Publications- Astronomical Society of Japan
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    ABSTRACT: The main goal of the JEM-EUSO experiment is the study of Ultra High Energy Cosmic Rays (UHECR, 1019−1021eV), but the method which will be used (detection of the secondary light emissions induced by cosmic rays in the atmosphere) allows to study other luminous phenomena. The UHECRs will be detected through the measurement of the emission in the range between 290 and 430 m, where some part of Transient Luminous Events (TLEs) emission also appears. This work discusses the possibility of using the JEM-EUSO Telescope to get new scientific results on TLEs. The high time resolution of this instrument allows to observe the evolution of TLEs with great precision just at the moment of their origin. The paper consists of four parts: review of the present knowledge on the TLE, presentation of the results of the simulations of the TLE images in the JEM-EUSO telescope, results of the Russian experiment Tatiana–2 and discussion of the possible progress achievable in this field with JEM-EUSO as well as possible cooperation with other space projects devoted to the study of TLE – TARANIS and ASIM. In atmospheric physics, the study of TLEs became one of the main physical subjects of interest after their discovery in 1989. In the years 1992 – 1994 detection was performed from satellite, aircraft and space shuttle and recently from the International Space Station. These events have short duration (milliseconds) and small scales (km to tens of km) and appear at altitudes 50 – 100 km. Their nature is still not clear and each new experimental data can be useful for a better understanding of these mysterious phenomena.
    Full-text · Article · Jul 2015 · Experimental Astronomy
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    ABSTRACT: The Extreme Universe Space Observatory (EUSO) on–board the Japanese Experimental Module (JEM) of the International Space Station aims at the detection of ultra high energy cosmic rays from space. The mission consists of a UV telescope which will detect the fluorescence light emitted by cosmic ray showers in the atmosphere. The mission, currently developed by a large international collaboration, is designed to be launched within this decade. In this article, we present the reconstruction of the energy of the observed events and we also address the Xmax reconstruction. After discussing the algorithms developed for the energy and Xmax reconstruction, we present several estimates of the energy resolution, as a function of the incident angle, and energy of the event. Similarly, estimates of the Xmax resolution for various conditions are presented.
    Full-text · Article · Jul 2015 · Experimental Astronomy
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    ABSTRACT: Extended emission is a mystery in short gamma-ray bursts (SGRBs). By making time resolved spectral analyses of brightest eight events observed by {\it Swift} XRT, we obviously classify the early X-ray emission of SGRBs into two types. One is the extended emission with exponentially rapid decay, which shows significant spectral softening during hundreds seconds since the SGRB trigger and is also detected by {\it Swift}-BAT. The other is a dim afterglow only showing power-law decay over $10^4$ s. The correlations between the temporal decay and spectral indices of the extended emissions are inconsistent with the $\alpha$-$\beta$ correlation expected for the high-latitude curvature emission from a uniform jet. The observed too-rapid decay suggests the emission from a photosphere or a patchy surface, and manifests the stopping central engine via such as magnetic reconnection at the black hole.
    Preview · Article · Jun 2015 · The Astrophysical Journal
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    ABSTRACT: ASTRO-H, the sixth Japanese X-ray observatory, which is scheduled to be launched by the end of Japanese fiscal year 2015 has a capability to observe the prompt emission from Gamma-ray Bursts (GRBs) utilizing BGO active shields for the soft gamma-ray detector (SGD). The effective area of the SGD shield detectors is very large and its data acquisition system is optimized for short transients such as short GRBs. Thus, we expect to perform more detailed time-resolved spectral analysis with a combination of ASTRO-H and Fermi LAT/GBM to investigate the gamma-ray emission mechanism of short GRBs. In addition, the environment of the GRB progenitor should be a remarkable objective from the point of view of the chemical evolution of high-z universe. If we can maneuver the spacecraft to the GRBs, we can perform a high-resolution spectroscopy of the X-ray afterglow of GRBs utilizing the onboard micro calorimeter and X-ray CCD camera.
    Full-text · Article · Mar 2015
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    ABSTRACT: The joint JAXA/NASA ASTRO-H mission is the sixth in a series of highly successful X-ray missions developed by the Institute of Space and Astronautical Science (ISAS), with a planned launch in 2015. The ASTRO-H mission is equipped with a suite of sensitive instruments with the highest energy resolution ever achieved at E > 3 keV and a wide energy range spanning four decades in energy from soft X-rays to gamma-rays. The simultaneous broad band pass, coupled with the high spectral resolution of Delta E < 7 eV of the micro-calorimeter, will enable a wide variety of important science themes to be pursued. ASTRO-H is expected to provide breakthrough results in scientific areas as diverse as the large-scale structure of the Universe and its evolution, the behavior of matter in the gravitational strong field regime, the physical conditions in sites of cosmic-ray acceleration, and the distribution of dark matter in galaxy clusters at different redshifts.
    Full-text · Article · Dec 2014
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    ABSTRACT: In this paper, we demonstrate ASTRO-H's capability to measure the chemical evolution in the high-z (z <~ 3) universe by observing X-ray afterglows of gamma-ray bursts (GRBs) and distant Blazars. Utilizing these sources as background light sources, the excellent energy resolution of ASTRO-H/SXS allows us to detect emission and absorption features from heavy elements in the circumstellar material in the host galaxies, from the intergalactic medium (IGM) and in the ejecta of GRB explosions. In particular, we can constrain the existence of the warm-hot intergalactic material (WHIM), thought to contain most of the baryons at redshift of z < ~3, with a typical exposure of one day for a follow-up observation of a GRB afterglow or 300 ks exposure for several distant Blazars. In addition to the chemical evolution study, the combination of the SGD, HXI, SXI and SXS will measure, for the first time, the temporal behavior of the spectral continuum of GRB afterglows and Blazars over a broad energy range and short time scales allowing detailed modeling of jets. The ability to obtain these data from GRB afterglows will depend critically on the availability of GRB triggers and the capability of ASTRO-H to respond rapidly to targets of opportunity. At the present time it seems as if Swift will still be functioning normally during the first two years of ASTRO-H operations providing the needed triggering capability.
    Full-text · Article · Dec 2014
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    Full-text · Dataset · Nov 2014
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    ABSTRACT: The hard X-ray imager (HXI) and soft gamma-ray detector (SGD) onboard Astro-H observe astronomical objects with high sensitivity in the hard X-ray (5-80 keV) and soft gamma-ray (40-600 keV) energy bands. To achieve this high sensitivity, background rejection is essential, and these detectors are surrounded by large and thick bismuth germinate scintillators as an active shield. We have developed adequate trigger logic for both the HXI and SGD to process signals from main detector and BGO shield simultaneously and then we optimized the trigger delay and width, with consideration of the trigger latch efficiency. The shield detector system performs well, even after it is assembled as the HXI sensor. The energy threshold maintains the same level as that observed during the prototype development phase, and the experimental room background level of the main detector is successfully reduced by our optimized trigger timing.
    No preview · Article · Jul 2014 · Proceedings of SPIE - The International Society for Optical Engineering
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    ABSTRACT: The Soft Gamma-ray Detector (SGD) is one of observational instruments onboard the ASTRO-H, and will provide 10 times better sensitivity in 60{600 keV than the past and current observatories. The SGD utilizes similar technologies to the Hard X-ray Imager (HXI) onboard the ASTRO-H. The SGD achieves low background by constraining gamma-ray events within a narrow field-of-view by Compton kinematics, in addition to the BGO active shield. In this paper, we will present the results of various tests using engineering models and also report the flight model production and evaluations.
    No preview · Article · Jul 2014 · Proceedings of SPIE - The International Society for Optical Engineering
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    ABSTRACT: We are now investigating and studying a small satellite mission HiZ-GUNDAM for future observation of gamma-ray bursts (GRBs). The mission concept is to probe "the end of dark ages and the dawn of formation of astronomical objects", i.e. the physical condition of early universe beyond the redshift z > 7. We will consider two kinds of mission payloads, (1) wide field X-ray imaging detectors for GRB discovery, and (2) a near infrared telescope with 30 cm in diameter to select the high-z GRB candidates effectively. In this paper, we explain some requirements to promote the GRB cosmology based on the past observations, and also introduce the mission concept of HiZ-GUNDAM and basic development of X-ray imaging detectors.
    Full-text · Article · Jun 2014 · Proceedings of SPIE - The International Society for Optical Engineering
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    ABSTRACT: Using 72 Short Gamma Ray Bursts (SGRBs) with well determined spectral data observed by BATSE, we determine their redshift and the luminosity by applying $E_p$--$L_p$ correlation for SGRBs found by Tsutsui et al. (2013). For 53 SGRBs with the observed flux brighter than $4 \times 10^{-6}~{\rm erg~cm^{-2}s^{-1}}$, the cumulative redshift distribution up to $z=1$ agrees well with that of 22 Swift SGRBs. Especially good agreement is seen for $z < 0.4$ with the KS chance probability of 5.3\%. This suggests that the redshift determination by the $E_p$--$L_p$ correlation for SGRBs works very well. The minimum event rate at $z=0$ is estimated as $R_{\rm on-axis}^{\rm min} = 2 \times 10^{-10}~{\rm events~Mpc^{-3}yr^{-1}}$ so that the minimum beaming angle is $0.57^\circ-3.6^\circ$ assuming the merging rate of $10^{-7}-4\times 10^{-6}~{\rm events~yr^{-1}galaxy^{-1}}$ suggested from the binary pulsar data. Interestingly, this angle is consistent with that for SGRB~130603B of $\sim 4^\circ-8^\circ$ (Fong et al. 2013). On the other hand, if we assume the beaming angle of $\sim 6^\circ$ suggested from four SGRBs, the minimum event rate including off-axis SGRBs is estimated as $R_{\rm all}^{\rm min}\sim 4\times 10^{-8}~{\rm events~Mpc^{-3}yr^{-1}}$. If SGRBs are induced by coalescence of binary neutron stars (NSs) and/or black holes (BHs), this event rate leads to the minimum gravitational-wave detection rate of $\rm 1.3 (50)~events~yr^{-1}$ for NS-NS (NS-BH) binary, respectively, by KAGRA, adv-LIGO, adv-Virgo and GEO network.
    Preview · Article · Feb 2014 · The Astrophysical Journal
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    Full-text · Dataset · Jan 2014
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    ABSTRACT: Solar Power Sail is a novel spacecraft with hybrid propulsion of large-area solar sail and electric propulsion driven by thin-film solar panel. The Solar Power Sail spacecraft is currently developed to probe into the outer-solar system bodies out to the Jupiter orbit, which was not well precedently explored. This mission aims to explore Trojan asteroids and interplanetary dusts by remote sensing and in-situ sampling using orbital rendezvous or fly-by technique. Scientific objective of this mission is not only planetary science but also novel astronomy; measurement of the infrared extragalactic background light without foreground contamination of the zodiacal light thanks to low-density environment at deep space, polarization measurement of the gamma-ray burst and accurate determination of its direction based on the interplanetary network technique. The Solar Power Sail mission will thus develop a new direction of space astronomy and planetary science providing us an interplanetary telescope site and will play an important roll to form a new interdisciplinary science field.
    No preview · Article · Jan 2014 · Transactions of the Japan Society for Aeronautical and Space Sciences, Aerospace Technology Japan
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    ABSTRACT: This paper presents the extended missions of the IKAROS solar sail interplanetary spacecraft. IKAROS entered an extended operation phase at the beginning of 2011. During this phase, its spin rate was reduced to observe deformation of the sail membrane under low centrifugal forces, and on Oct. 18, 2011 the spin was reversed to enhance knowledge of the membrane’s stiffness against solar radiation pressure. We also investigated changes in IKAROS’s attitude motions under reverse spin conditions. At the end of 2011, IKAROS switched to hibernation mode due to an increased Sun angle reducing on-board electricity generation. We later searched for IKAROS considering its attitude and orbital motion during hibernation, and on Sep. 6, 2012, we succeeded in locating the spacecraft, which came out of hibernation.A solar power sail can be part of a hybrid propulsion system, with electrical power generated by thin-film solar cells on a solar sail membrane being used to operate ultra-high specific impulse ion engines. This paper also introduces a follow-on mission to IKAROS, a round trip to the Trojan asteroid using hybrid electric photon propulsion.
    Full-text · Article · Jan 2014 · Transactions of the Japan Society for Aeronautical and Space Sciences, Aerospace Technology Japan

Publication Stats

2k Citations
168.07 Total Impact Points

Institutions

  • 2002-2015
    • Kanazawa University
      • • Department of Physics
      • • School of Mathematics and Physics
      Kanazawa, Ishikawa, Japan
  • 2007
    • Japan Aerospace Exploration Agency
      • Institute of Space and Astronautical Science (ISAS)
      Chōfu, Tokyo, Japan
  • 2001
    • Tokyo Institute of Technology
      • Department of Physics
      Edo, Tokyo, Japan
    • Saitama University
      • Department of Physics
      Саитама, Saitama, Japan