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Sep 21, 2013
09/13
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S. Nagataki
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In order to investigate formation of relativistic jets at the center of a progenitor of a long gamma-ray burst (GRB), we develop a two-dimensional general relativistic magnetohydrodynamic (GRMHD) code. We show the code passes many, well-known test calculations, by which the reliability of the code is confirmed. Then we perform a numerical simulation of a collapsar using a realistic progenitor model. It is shown that a jet is launched from the center of the progenitor. We also find that the mass...
Source: http://arxiv.org/abs/0902.1908v1
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51
Sep 21, 2013
09/13
by
S. Nagataki
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eye 51
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We study the effects of jet-like explosion in SN 1987A. Calculations of the explosive nucleosynthesis and the matter mixing in a jet-like explosion are performed and their results are compared with the observations of SN 1987A. It is shown that the jet-like explosion model is favored because the radioactive nuclei 44Ti is produced in a sufficient amount to explain the observed bolometric luminosity at 3600 days after the explosion. It is also shown that the observed line profiles of Fe[II] are...
Source: http://arxiv.org/abs/astro-ph/9907109v7
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Sep 22, 2013
09/13
by
S. Nagataki
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eye 78
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We have estimated fluxes of neutrinos and gamma-rays that are generated from decays of charged and neutral pions from a pulsar surrounded by supernova ejecta in our galaxy, including an effect that has not been taken into consideration, that is, interactions between high energy cosmic rays themselves in the nebula flow, assuming that hadronic components are the energetically dominant species in the pulsar wind. Bulk flow is assumed to be randomized by passing through the termination shock and...
Source: http://arxiv.org/abs/astro-ph/0309715v1
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43
Sep 19, 2013
09/13
by
S. Nagataki
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We have studied whether the jet in a collapse-driven supernova can be a key process for the rapid-process (r-process) nucleosynthesis. We have examined the features of a steady, subsonic, and rigidly rotating jet in which the centrifugal force is balanced by the magnetic force. As for the models in which the magnetic field is weak and angular velocity is small, we found that the r-process does not occur because the final temperature is kept to be too high and the dynamical timescale becomes too...
Source: http://arxiv.org/abs/astro-ph/0010069v2
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45
Sep 18, 2013
09/13
by
S. Nagataki
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eye 45
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We have estimated the number flux of of mu-neutrinos which are produced due to the hadronic interactions between the cosmic rays coming from a neutron star and the matter in a companion star. The event rate at 1 km^2 detectors of high-energy neutrinos such as ICECUBE, ANTARES and NESTOR is also estimated to be 2.7 \times 10^4 events yr^-1 when the source is located at 10 kpc away from the Earth. We have estimated the number of such a system and concluded that there will be several candidates in...
Source: http://arxiv.org/abs/hep-ph/0202243v2
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43
Sep 22, 2013
09/13
by
S. Nagataki; K. Kohri
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eye 43
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In this study we present two indicators that will reflect the difference between collapsars and normal collapse-driven supernovae. They are products of explosive nucleosynthesis and neutrino emission. In the collapsar model, it is natural to consider that the product of explosive nucleosynthesis depends on the zenith angle because the system becomes highly asymmetric in order to generate a fire ball. We also consider the detectability of the HNRs which is located nearby our Galaxy. As a result,...
Source: http://arxiv.org/abs/astro-ph/0003066v2
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63
Sep 21, 2013
09/13
by
K. Kotake; S. Nagataki
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eye 63
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We present a model explaining the Fe K alpha line and the continuum in the afterglow of GRB000214. We pose the importance to seek the physically natural environment around GRB000214. For the reproduction of the observation, we need the ring-like remnant around the progenitor like that of SN 1987A produced by the mass-loss of the progenitor and the fireball spread over in every directions. The observation of GRB000214, in which the continuum power law spectrum decreased faster than the line,...
Source: http://arxiv.org/abs/astro-ph/0104485v4
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48
Sep 22, 2013
09/13
by
S. Nagataki; K. Sato
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eye 48
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The origin of the chemical composition of the intracluster medium (ICM) is discussed in this paper. In particular, the contribution from Type Ia supernovae (SNe Ia) to the ICM enrichment is shown to exist by adopting the fitting formulas which have been used in the analysis of the solar system abundances. Our analysis means that we can use the frequency of SNe Ia relative to SNe II as the better measure than $M_{Fe, SN Ia}/M_{Fe, total}$ for estimating the contribution of SNe Ia. Moreover, the...
Source: http://arxiv.org/abs/astro-ph/9807022v1
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54
Sep 21, 2013
09/13
by
S. Nagataki; G. Watanabe
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eye 54
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We present a new input parameter set of the Pagel model (Pagel & Tautvai$\rm \breve{s}$ien$\rm \dot{e}$ 1998) for the Large Magellanic Cloud (LMC) in order to reproduce the observations, including the star formation rate (SFR) history. It is concluded that the probability for (3-8)$M_{\odot}$ stars to explode as SNe Ia has to be quite high ($\sim 0.17$) in the LMC. As a result, a steep initial mass function (IMF) slope and existence of the outflow are not needed in order to attain the low...
Source: http://arxiv.org/abs/astro-ph/9907108v2
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49
Sep 18, 2013
09/13
by
S. Nagataki; K. Kohri
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eye 49
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We have studied whether the rotation and magnetic fields in neutrino-driven winds can be key processes for the rapid-process (r-process) nucleosynthesis. We have examined the features of a steady and subsonic wind solutions which extend the model of Weber and Davis (1967), which is a representative solar wind model. As a result, we found that the entropy per baryon becomes lower and the dynamical timescale becomes longer as the angular velocity becomes higher. These results are inappropriate...
Source: http://arxiv.org/abs/astro-ph/0101347v1
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42
Sep 22, 2013
09/13
by
S. Nagataki; K. Sato
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eye 42
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From the observation of a millisecond pulsar in SN 1987A, the following implications are obtained. 1) The pulsar spindown in SN 1987A is caused by radiating gravitational waves rather than by magnetic dipole radiation and/or relativistic pulsar winds. 2) A mildly deformed shock wave would be formed at the core-collapse and explosion in SN 1987A, which is consistent with the conclusion given in Nagataki (2000). 3) The gravitational waves from the pulsar should be detected in several years using...
Source: http://arxiv.org/abs/astro-ph/0011363v3
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73
Sep 22, 2013
09/13
by
K. Asano; S. Nagataki
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eye 73
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We simulate neutrino production in a gamma-ray burst (GRB) with the most detailed method to date. We show that the highest energy neutrinos from GRBs mainly come from kaons. Although there is little chance to detect such neutrinos, attempts of detection are very important to prove physical conditions in GRBs.
Source: http://arxiv.org/abs/astro-ph/0603107v1
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56
Sep 19, 2013
09/13
by
K. Kohri; S. Nagataki
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eye 56
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We have investigated the relation of the direction of the momentum among the matter, neutrino, and proto-neutron star in a collapse-driven supernova in order to discuss the pulsar kick. In particular, we have investigated the effects of the pulsar motion on the explosion, which are neglected in the previous study. As a result, it is suggested that the direction of the total momentum of the matter and neutrino is opposite to that of the momentum of the proto-neutron star in the asymmetric...
Source: http://arxiv.org/abs/astro-ph/9911077v2
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57
Sep 22, 2013
09/13
by
S. Nagataki; M. Hashimoto; K. Sato
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eye 57
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We have estimated the dispersion of the inferred relative frequencies of Type-Ia and Type- II supernovae ($N_{Ia}/ N_{II}$) in our Galaxy by fitting the numerical results of supernova nucleosynthesis to the solar-system abundances. The ratio $N_{Ia}/ N_{II}$ is estimated to be 0.056--0.14, which is consistent with the observation, if the model of Woosley and Weaver (1995, WW95) is adopted for Type-II supernovae (SNe II). On the other hand, the upper limit of $N_{Ia}/ N_{II}$ becomes too large...
Source: http://arxiv.org/abs/astro-ph/9807016v1
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42
Sep 22, 2013
09/13
by
S. Nagataki; M. Hashimoto; S. Yamada
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eye 42
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We have performed 1-dimensional calculations for explosive nucleosynthesis in collapse-driven supernova and investigated its sensitivity to the initial form of the shock wave. We have found the tendency that the peak temperature becomes higher around the mass cut if the input energy is injected more in the form of kinetic energy rather than internal energy. Then, the mass cut becomes larger, and, as a result, neutron-rich matter is less included in the ejecta; this is favorable for producing...
Source: http://arxiv.org/abs/astro-ph/9807014v1
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36
Sep 22, 2013
09/13
by
K. Kohri; Shoichi Yamada; S. Nagataki
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eye 36
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We study the equation of state of electron in strong magnetic fields which are greater than the critical value $B_c \simeq 4.4 \times 10^{13}$ Gauss. We find that such a strong magnetic field induces the anisotropic pressure of electron. We apply the result to the neutrino-driven wind in core-collapse supernovae and find that it can produce large entropy per baryon, $S \sim 400 k_B$. This mechanism might successfully account for the production of the heavy nuclei with mass numbers A = 80 -- 250...
Source: http://arxiv.org/abs/hep-ph/0106271v1
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49
Sep 22, 2013
09/13
by
H. Yoshiguchi; S. Nagataki; K. Sato
texts
eye 49
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We present a new method for calculating arrival distribution of UHECRs including modifications by the galactic magnetic field. We perform numerical simulations of UHE anti-protons, which are injected isotropically at the earth, in the Galaxy and record the directions of velocities at the earth and outside the Galaxy for all of the trajectories. We then select some of them so that the resultant mapping of the velocity directions outside the Galaxy of the selected trajectories corresponds to a...
Source: http://arxiv.org/abs/astro-ph/0307038v1
46
46
Sep 19, 2013
09/13
by
D. A. Prokhorov; Y. Dubois; S. Nagataki
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eye 46
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Measurements of the Sunyaev-Zel'dovich (hereafter SZ) effect distortion of the cosmic microwave background provide us with an independent method to derive the gas temperature of galaxy clusters. In merging galaxy clusters the gas distribution is inhomogeneous and, therefore, the method of temperature measuring based on the SZ effect should be more relevant than that based on an X-ray emission analysis. Here we study a method for measuring the gas temperature in merging clusters by means of the...
Source: http://arxiv.org/abs/1009.3305v1
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41
Sep 21, 2013
09/13
by
M. Xu; S. Nagataki; Y. F. Huang
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eye 41
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We propose an off-axis relativistic jet model for the Type Ic supernova SN 2007gr. Most of the energy ($\sim2\times10^{51}$ erg) in the explosion is contained in non-relativistic ejecta which produces the supernova. The optical emission is coming from the decay process of $\rm ^{56}Ni$ synthesized in the bulk SN ejecta. Only very little energy ($\sim10^{48}$ erg) is contained in the relativistic jet with initial velocity about 0.94 times the speed of light. The radio and X-ray emission comes...
Source: http://arxiv.org/abs/1104.0754v2
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50
Sep 21, 2013
09/13
by
S. Nagataki; K. Kohri; S. Ando; K. Sato
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eye 50
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We estimate the flux of the GRB neutrino background and compute the event rate at SK and TITAND in the collapsar model, assuming that GRB formation rate is proportional to the star formation rate. We find that the flux and the event rate depend sensitively on the mass-accretion rate. Although the detection of signals from GRBs seems to be difficult by SK, we find that we can detect them by TITAND (optimistically about 20 events per year in the energy range where the energy of anti-electron...
Source: http://arxiv.org/abs/astro-ph/0203481v1
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44
Sep 18, 2013
09/13
by
H. Yoshiguchi; S. Nagataki; S. Tsubaki; K. Sato
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eye 44
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We present numerical simulations on the propagation of UHE protons with energies of $(10^{19.5}-10^{22})$ eV in extragalactic magnetic fields over 1 Gpc. We use the ORS galaxy sample, which allow us to accurately quantify the contribution of nearby sources to the energy spectrum and the arrival distribution, as a source model. We calculate three observable quantities, cosmic ray spectrum, harmonic amplitude, and two point correlation function from our data of numerical simulations. With these...
Source: http://arxiv.org/abs/astro-ph/0210132v3
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60
Sep 18, 2013
09/13
by
F. Iocco; K. Murase; S. Nagataki; P. D. Serpico
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eye 60
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We perform a new estimate of the high energy neutrinos expected from GRBs associated with the first generation of stars in light of new models and constraints on the epoch of reionization and a more detailed evaluation of the neutrino emission yields. We also compare the diffuse high energy neutrino background from Population III stars with the one from "ordinary stars" (Population II), as estimated consistently within the same cosmological and astrophysical assumptions. In...
Source: http://arxiv.org/abs/0707.0515v2
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60
Sep 22, 2013
09/13
by
Y. Ide; S. Nagataki; S. Tsubaki; H. Yoshiguchi; K. Sato
texts
eye 60
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We have performed the detailed numerical simulations on the propagation of the UHE protons in the energy range $E=(10^{19.5} - 10^{22.0}$) eV in the relatively strong extra-galactic magnetic field with strength $B= (10, 100)$ nG within about 40 Mpc. In this case, the deflection angles of UHECRs become so large that the no counterparts problem is simply solved. As for the source distribution, we assumed that it is proportional to the number distribution of galaxies within the GZK sphere. We have...
Source: http://arxiv.org/abs/astro-ph/0106182v1
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53
Sep 18, 2013
09/13
by
S. Nagataki; A. Mizuta; S. Yamada; H. Takabe; K. Sato
texts
eye 53
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We perform 2-dimensional relativistic hydrodynamical simulations in the context of collapsar model. Calculations of explosive nucleosynthesis are also accomplished. We investigate the influence of the structure of the progenitor and energy deposition rate on the resulting explosive nucleosynthesis, assuming that 56Ni is mainly synthesized in the jet launched by the neutrino heating. We show the amount of 56Ni is very sensitive to the energy deposition rate. Thus we conclude that it is quite...
Source: http://arxiv.org/abs/astro-ph/0306417v1
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46
Sep 18, 2013
09/13
by
H. Yoshiguchi; S. Nagataki; K. Sato; N. Ohama; S. Okamura
texts
eye 46
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If Ultra-High Energy Cosmic Rays (UHECRs) are originated from nearby galaxies, modeling of the distribution of nearby galaxies is important to an accurate estimate the source number density of UHECRs. We investigate uncertainty of the selection function of the Optical Redshift Survey (ORS), which we used to construct a source model of UHECRs. The investigation is based on a comparison of numbe counts of ORS galaxies with those of the spectroscopic sample of the Sloan Digital Sky Survey (SDSS)...
Source: http://arxiv.org/abs/astro-ph/0212061v2
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122
Sep 23, 2013
09/13
by
M. Xu; S. Nagataki; Y. -F. Huang; S. -H. Lee
texts
eye 122
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We show that the photospheres of "failed" Gamma-Ray Bursts (GRBs), whose bulk Lorentz factors are much lower than 100, can be outside of internal shocks. The resulting radiation from the photospheres is thermal and bright in UV/Soft X-ray band. The photospheric emission lasts for about one thousand seconds with luminosity about several times 10^46 erg/s. These events can be observed by current and future satellites. It is also shown that the afterglows of failed GRBs are peculiar at...
Source: http://arxiv.org/abs/1111.7084v1
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37
Sep 21, 2013
09/13
by
D. A. Prokhorov; Y. Dubois; S. Nagataki; T. Akahori; K. Yoshikawa
texts
eye 37
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The Sunyaev-Zel'dovich (hereafter SZ) effect is a promising tool to derive the gas temperature of galaxy clusters. The approximation of a spherically symmetric gas distribution is usually used to determine the temperature structure of galaxy clusters, but this approximation cannot properly describe merging galaxy clusters. The methods used so far, which do not assume the spherically symmetric distribution, permit us to derive 2D temperature maps of merging galaxy clusters. In this paper, we...
Source: http://arxiv.org/abs/1104.2357v1
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49
Sep 22, 2013
09/13
by
S. Nagataki; M. Hashimoto; K. Sato; S. Yamada; Y. S. Mochizuki
texts
eye 49
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The large abundance ratio of $^{44}Ti/^{56}Ni$ in Cas A is puzzling. In fact, the ratio seems to be larger than the theoretical constraint derived by Woosley & Hoffman (1991). However, this constraint is obtained on the assumption that the explosion is spherically symmetric, whereas Cas A is famous for the asymmetric form of the remnant. Recently, Nagataki et al. (1997) calculated the explosive nucleosynthesis of axisymmetrically deformed collapse-driven supernova. They reported that the...
Source: http://arxiv.org/abs/astro-ph/9807015v1
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13
Jun 27, 2018
06/18
by
M. G. Dainotti; V. Petrosian; R. Willingale; P. O' Brien; M. Ostrowski; S. Nagataki
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eye 13
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We present an analysis of 123 Gamma-ray bursts (GRBs) with known redshifts possessing an afterglow plateau phase. We reveal that $L_a-T^{*}_a$ correlation between the X-ray luminosity $L_a$ at the end of the plateau phase and the plateau duration, $T^*_a$, in the GRB rest frame has a power law slope different, within more than 2 $\sigma$, from the slope of the prompt $L_{f}-T^{*}_{f}$ correlation between the isotropic pulse peak luminosity, $L_{f}$, and the pulse duration, $T^{*}_{f}$, from the...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1506.00702
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46
Sep 23, 2013
09/13
by
D. A. Prokhorov; S. Colafrancesco; T. Akahori; K. Yoshikawa; S. Nagataki; K. -I. Seon
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eye 46
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Measurements of the Sunyaev-Zel'dovich (hereafter SZ) effect distortion of the cosmic microwave background provide methods to derive the gas pressure and temperature of galaxy clusters. Here we study the ability of SZ effect observations to derive the electron distribution function (DF) in massive galaxy clusters. Our calculations of the SZ effect include relativistic corrections considered within the framework of the Wright formalism and use a decomposition technique of electron DFs into...
Source: http://arxiv.org/abs/1105.3517v1
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50
Sep 23, 2013
09/13
by
D. A. Prokhorov; S. Colafrancesco; T. Akahori; E. T. Million; S. Nagataki; K. Yoshikawa
texts
eye 50
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High-frequency, high-resolution imaging of the Sunyaev-Zel'dovich (SZ) effect is an important technique to study the complex structures of the atmospheres of merging galaxy clusters. Such observations are sensitive to the details of the electron spectrum. We show that the morphology of the SZ intensity maps in simulated galaxy clusters observed at 345 GHz, 600 GHz, and 857 GHz are significantly different because of SZ relativistic corrections. These differences can be revealed by...
Source: http://arxiv.org/abs/1105.4271v1
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8.0
Jun 28, 2018
06/18
by
J. Mao; M. Ono; S. Nagataki; M. Hashimoto; H. Ito; J. Matsumoto; M. G. Dainotti; S. -H. Lee
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eye 8
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Matter mixing is one important topic in the study of core-collapse supernova (CCSN) explosions. In this paper, we perform two-dimensional hydrodynamic simulations to reproduce the high velocity $^{56}$Ni clumps observed in SN 1987A. This is the first time that large density perturbation is proposed in the CCSN progenitor to generate Rayleigh-Taylor (RT) instability and make the effective matter mixing. In the case of a spherical explosion, RT instability is efficient at both C+O/He and He/H...
Topics: High Energy Astrophysical Phenomena, Solar and Stellar Astrophysics, Astrophysics
Source: http://arxiv.org/abs/1507.07061
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4.0
Jun 30, 2018
06/18
by
P. Slane; S. -H. Lee; D. C. Ellison; D. J. Patnaude; J. P. Hughes; K. A. Eriksen; D. Castro; S. Nagataki
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eye 4
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Tycho's supernova remnant (SNR) is well-established as a source of particle acceleration to very high energies. Constraints from numerous studies indicate that the observed gamma-ray emission results primarily from hadronic processes, providing direct evidence of highly relativistic ions that have been accelerated by the SNR. Here we present an investigation of the dynamical and spectral evolution of Tycho's SNR by carrying out hydrodynamical simulations that include diffusive shock...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1401.2556
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70
Jul 20, 2013
07/13
by
J. Takata; A. T. Okazaki; S. Nagataki; T. Naito; A. Kawachi; S. -H. Lee; M. Mori; K. Hayasaki; M. S. Yamaguchi; S. P. Owocki
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eye 70
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Temporal changes of X-ray to very-high-energy gamma-ray emissions from the pulsar-Be star binary PSR B1259-63/LS 2883 are studied based on 3-D SPH simulations of pulsar wind interaction with Be-disk and wind. We focus on the periastron passage of the binary and calculate the variation of the synchrotron and inverse-Compton emissions using the simulated shock geometry and pressure distribution of the pulsar wind. The characteristic double-peaked X-ray light curve from observations is reproduced...
Source: http://arxiv.org/abs/1203.2179v2
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55
Sep 22, 2013
09/13
by
J. M. Paredes; W. Bednarek; P. Bordas; V. Bosch-Ramon; E. De Cea del Pozo; G. Dubus; S. Funk; D. Hadasch; D. Khangulyan; S. Markoff; J. Moldon; P. Munar-Adrover; S. Nagataki; T. Naito; M. de Naurois; G. Pedaletti; O. Reimer; M. Ribo; A. Szostek; Y. Terada; D. F. Torres; V. Zabalza; A. A. Zdziarski; for the CTA Consortium
texts
eye 55
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The binary systems that have been detected in gamma rays have proven very useful to study high-energy processes, in particular particle acceleration, emission and radiation reprocessing, and the dynamics of the underlying magnetized flows. Binary systems, either detected or potential gamma-ray emitters, can be grouped in different subclasses depending on the nature of the binary components or the origin of the particle acceleration: the interaction of the winds of either a pulsar and a massive...
Source: http://arxiv.org/abs/1210.3215v1
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14
Jun 28, 2018
06/18
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T. Nakamori; H. Katagiri; H. Sano; R. Yamazaki; Y. Ohira; A. Bamba; Y. Fukui; K. Mori; S. -H. Lee; Y. Fujita; H. Tajima; T. Inoue; S. Gunji; Y. Hanabata; M. Hayashida; H. Kubo; J. Kushida; S. Inoue; K. Ioka; K. Kohri; K. Murase; S. Nagataki; T. Naito; A. Okumura; T. Saito; M. Sawada; T. Tanaka; Y. Terada; Y. Uchiyama; S. Yanagita; T. Yoshida; T. Yoshikoshi; for the CTA Consortium
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We perform simulations of Cherenkov Telescope Array (CTA) observations of a young supernova remnant RX J1713.7-3946. This target is not only one of the brightest sources ever discovered in very high-energy gamma rays but also well observed in other wavebands. In X-rays, the emission is dominated by synchrotron radiation, which links directly to the existence of high-energy electrons. Radio observations of CO and HI gas have revealed a highly inhomogeneous medium surrounding the SNR, such as...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1508.06052
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7.0
Jun 29, 2018
06/18
by
R. U. Abbasi; M. Abe; T. Abu-Zayyad; M. Allen; R. Azuma; E. Barcikowski; J. W. Belz; D. R. Bergman; S. A. Blake; R. Cady; B. G. Cheon; A. Taketa; M. Takita; Y. Tameda; M. Tanaka; K. Tanaka; H. Tanaka; S. B. Thomas; G. B. Thomson; P. Tinyakov; A. H. Tirone; J. Chiba; I. Tkachev; H. Tokuno; T. Tomida; S. Troitsky; Y. Tsunesada; K. Tsutsumi; Y. Uchihori; S. Udo; F. Urban; T. Wong; M. Chikawa; R. Yamane; H. Yamaoka; K. Yamazaki; J. Yang; K. Yashiro; Y. Yoneda; S. Yoshida; H. Yoshii; R. Zollinger;...
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Cosmic rays in the energy range $10^{18.0}$ - $10^{18.5}$ eV are thought to have a light, probably protonic, composition. To study their origin one can search for anisotropy in their arrival directions. Extragalactic cosmic rays should be isotropic, but galactic cosmic rays of this type should be seen mostly along the galactic plane, and there should be a shortage of events coming from directions near the galactic anticenter. This is due to the fact that, under the influence of the galactic...
Topics: Astrophysics, High Energy Astrophysical Phenomena
Source: http://arxiv.org/abs/1608.06306
3
3.0
Jun 30, 2018
06/18
by
R. U. Abbasi; M. Abe; T. Abu-Zayyad; M. Allen; R. Anderson; R. Azuma; E. Barcikowski; J. W. Belz; D. R. Bergman; S. A. Blake; R. Cady; K. Tanaka; M. Tanaka; S. B. Thomas; G. B. Thomson; P. Tinyakov; I. Tkachev; H. Tokuno; T. Tomida; S. Troitsky; Y. Tsunesada; M. J. Chae; K. Tsutsumi; Y. Uchihori; S. Udo; F. Urban; G. Vasiloff; T. Wong; R. Yamane; H. Yamaoka; K. Yamazaki; J. Yang; B. G. Cheon; K. Yashiro; Y. Yoneda; S. Yoshida; H. Yoshii; R. Zollinger; Z. Zundel; J. Chiba; M. Chikawa; W. R. Cho;...
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We report on the search for steady point-like sources of neutral particles around 10$^{18}$ eV between 2008 May and 2013 May with the scintillator surface detector of the Telescope Array experiment. We found overall no significant point-like excess above 0.5 EeV in the northern sky. Subsequently, we also searched for coincidence with the Fermi bright Galactic sources. No significant coincidence was found within the statistical uncertainty. Hence, we set an upper limit on the neutron flux that...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1407.6145
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13
Jun 27, 2018
06/18
by
R. U. Abbasi; M. Abe; T. Abu-Zayyad; M. Allen; R. Anderson; R. Azuma; E. Barcikowski; J. W. Belz; D. R. Bergman; S. A. Blake; R. Cady; K. Tanaka; M. Tanaka; S. B. Thomas; G. B. Thomson; P. Tinyakov; I. Tkachev; H. Tokuno; T. Tomida; S. Troitsky; Y. Tsunesada; M. J. Chae; K. Tsutsumi; Y. Uchihori; S. Udo; F. Urban; G. Vasiloff; T. Wong; R. Yamane; H. Yamaoka; K. Yamazaki; J. Yang; B. G. Cheon; K. Yashiro; Y. Yoneda; S. Yoshida; H. Yoshii; R. Zollinger; Z. Zundel; J. Chiba; M. Chikawa; W. R. Cho;...
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In this work we are reporting on the measurement of the proton-air inelastic cross section $\sigma^{\rm inel}_{\rm p-air}$ using the Telescope Array (TA) detector. Based on the measurement of the $\sigma^{\rm inel}_{\rm p-air}$ the proton-proton cross section $\sigma_{\rm p-p}$ value is also determined at $\sqrt{s} = 95_{-8}^{+5}$ TeV. Detecting cosmic ray events at ultra high energies with Telescope Array enables us to study this fundamental parameter that we are otherwise unable to access...
Topics: High Energy Astrophysical Phenomena, Instrumentation and Methods for Astrophysics, Astrophysics,...
Source: http://arxiv.org/abs/1505.01860
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4.0
Jun 30, 2018
06/18
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The Telescope Array Collaboration; R. U. Abbasi; M. Abe; T. Abu-Zayyad; M. Allen; R. Anderson; R. Azuma; E. Barcikowski; J. W. Belz; D. R. Bergman; S. A. Blake; H. Tanaka; K. Tanaka; M. Tanaka; S. B. Thomas; G. B. Thomson; P. Tinyakov; I. Tkachev; H. Tokuno; T. Tomida; S. Troitsky; R. Cady; Y. Tsunesada; K. Tsutsumi; Y. Uchihori; S. Udo; F. Urban; G. Vasiloff; T. Wong; R. Yamane; H. Yamaoka; K. Yamazaki; M. J. Chae; J. Yang; K. Yashiro; Y. Yoneda; S. Yoshida; H. Yoshii; R. Zollinger; Z. Zundel;...
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We have searched for intermediate-scale anisotropy in the arrival directions of ultrahigh-energy cosmic rays with energies above 57~EeV in the northern sky using data collected over a 5 year period by the surface detector of the Telescope Array experiment. We report on a cluster of events that we call the hotspot, found by oversampling using 20$^\circ$-radius circles. The hotspot has a Li-Ma statistical significance of 5.1$\sigma$, and is centered at R.A.=146.7$^{\circ}$, Dec.=43.2$^{\circ}$....
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1404.5890
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80
Sep 20, 2013
09/13
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T. Abu-Zayyad; R. Aida; M. Allen; R. Anderson; R. Azuma; E. Barcikowski; J. W. Belz; D. R. Bergman; S. A. Blake; R. Cady; B. G. Cheon; J. Chiba; M. Chikawa; E. J. Cho; W. R. Cho; H. Fujii; T. Fujii; T. Fukuda; M. Fukushima; W. Hanlon; K. Hayashi; Y. Hayashi; N. Hayashida; K. Hibino; K. Hiyama; K. Honda; T. Iguchi; D. Ikeda; K. Ikuta; N. Inoue; T. Ishii; R. Ishimori; D. Ivanov; S. Iwamoto; C. C. H. Jui; K. Kadota; F. Kakimoto; O. Kalashev; T. Kanbe; K. Kasahara; H. Kawai; S. Kawakami; S. Kawana;...
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eye 80
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The Telescope Array (TA) collaboration has measured the energy spectrum of ultra-high energy cosmic rays with primary energies above 1.6 x 10^(18) eV. This measurement is based upon four years of observation by the surface detector component of TA. The spectrum shows a dip at an energy of 4.6 x 10^(18) eV and a steepening at 5.4 x 10^(19) eV which is consistent with the expectation from the GZK cutoff. We present the results of a technique, new to the analysis of ultra-high energy cosmic ray...
Source: http://arxiv.org/abs/1205.5067v3
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Jun 30, 2018
06/18
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R. U. Abbasi; M. Abe; T. Abu-Zayyad; M. Allen; R. Anderson; R. Azuma; E. Barcikowski; J. W. Belz; D. R. Bergman; S. A. Blake; R. Cady; H. Tanaka; K. Tanaka; M. Tanaka; S. B. Thomas; G. B. Thomson; P. Tinyakov; I. Tkachev; H. Tokuno; T. Tomida; S. Troitsky; M. J. Chae; Y. Tsunesada; K. Tsutsumi; Y. Uchihori; S. Udo; F. Urban; G. Vasiloff; T. Wong; R. Yamane; H. Yamaoka; K. Yamazaki; B. G. Cheon; J. Yang; K. Yashiro; Y. Yoneda; S. Yoshida; H. Yoshiia; R. Zollinger; Z. Zundel; J. Chiba; M....
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Previous measurements of the composition of Ultra-High Energy Cosmic Rays(UHECRs) made by the High Resolution Fly's Eye(HiRes) and Pierre Auger Observatory(PAO) are seemingly contradictory, but utilize different detection methods, as HiRes was a stereo detector and PAO is a hybrid detector. The five year Telescope Array(TA) Middle Drum hybrid composition measurement is similar in some, but not all, respects in methodology to PAO, and good agreement is evident between data and a light, largely...
Topics: Instrumentation and Methods for Astrophysics, High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1408.1726
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78
Sep 20, 2013
09/13
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T. Abu-Zayyad; R. Aida; M. Allen; R. Anderson; R. Azuma; E. Barcikowski; J. W. Belz; D. R. Bergman; S. A. Blake; R. Cady; B. G. Cheon; J. Chiba; M. Chikawa; E. J. Cho; W. R. Cho; H. Fujii; T. Fujii; T. Fukuda; M. Fukushima; W. Hanlon; K. Hayashi; Y. Hayashi; N. Hayashida; K. Hibino; K. Hiyama; K. Honda; T. Iguchi; D. Ikeda; K. Ikuta; N. Inoue; T. Ishii; R. Ishimori; D. Ivanov; S. Iwamoto; C. C. H. Jui; K. Kadota; F. Kakimoto; O. Kalashev; T. Kanbe; K. Kasahara; H. Kawai; S. Kawakami; S. Kawana;...
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We study the anisotropy of Ultra-High Energy Cosmic Ray (UHECR) events collected by the Telescope Array (TA) detector in the first 40 months of operation. Following earlier studies, we examine event sets with energy thresholds of 10 EeV, 40 EeV, and 57 EeV. We find that the distributions of the events in right ascension and declination are compatible with an isotropic distribution in all three sets. We then compare with previously reported clustering of the UHECR events at small angular scales....
Source: http://arxiv.org/abs/1205.5984v1
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52
Sep 23, 2013
09/13
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T. Abu-Zayyad; R. Aida; M. Allen; R. Anderson; R. Azuma; E. Barcikowski; J. W. Belz; D. R. Bergman; S. A. Blake; R. Cady; B. G. Cheon; J. Chiba; M. Chikawa; E. J. Cho; W. R. Cho; H. Fujii; T. Fujii; T. Fukuda; M. Fukushima; D. Gorbunov; W. Hanlon; K. Hayashi; Y. Hayashi; N. Hayashida; K. Hibino; K. Hiyama; K. Honda; T. Iguchi; D. Ikeda; K. Ikuta; N. Inoue; T. Ishii; R. Ishimori; D. Ivanov; S. Iwamoto; C. C. H. Jui; K. Kadota; F. Kakimoto; O. Kalashev; T. Kanbe; K. Kasahara; H. Kawai; S....
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The Telescope Array's Middle Drum fluorescence detector was instrumented with telescopes refurbished from the High Resolution Fly's Eye's HiRes-1 site. The data observed by Middle Drum in monocular mode was analyzed via the HiRes-1 profile-constrained geometry reconstruction technique and utilized the same calibration techniques enabling a direct comparison of the energy spectra and energy scales between the two experiments. The spectrum measured using the Middle Drum telescopes is based on a...
Source: http://arxiv.org/abs/1202.5141v1
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Jun 29, 2018
06/18
by
R. U. Abbasi; M. Abe; M. Abou Bakr Othman; T. Abu-Zayyad; M. Allen; R. Anderson; R. Azuma; E. Barcikowski; J. W. Belz; D. R. Bergman; D. Besson; B. T. Stokes; S. R. Stratton; T. A. Stroman; T. Suzawa; H. Takai; M. Takamura; M. Takeda; R. Takeishi; A. Taketa; M. Takita; S. A. Blake; Y. Tameda; H. Tanaka; K. Tanaka; M. Tanaka; S. B. Thomas; G. B. Thomson; P. Tinyakov; I. Tkachev; H. Tokuno; T. Tomida; M. Byrne; S. Troitsky; Y. Tsunesada; K. Tsutsumi; Y. Uchihori; S. Udo; F. Urban; G. Vasiloff; S....
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TARA (Telescope Array Radar) is a cosmic ray radar detection experiment colocated with Telescope Array, the conventional surface scintillation detector (SD) and fluorescence telescope detector (FD) near Delta, Utah, U.S.A. The TARA detector combines a 40 kW, 54.1 MHz VHF transmitter and high-gain transmitting antenna which broadcasts the radar carrier over the SD array and within the FD field of view, towards a 250 MS/s DAQ receiver. TARA has been collecting data since 2013 with the primary...
Topics: Astrophysics, Instrumentation and Methods for Astrophysics
Source: http://arxiv.org/abs/1603.05217
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69
Sep 17, 2013
09/13
by
T. Abu-Zayyad; R. Aida; M. Allen; R. Anderson; R. Azuma; E. Barcikowski; J. W. Belz; D. R. Bergman; S. A. Blake; R. Cady; B. G. Cheon; J. Chiba; M. Chikawa; E. J. Cho; W. R. Cho; H. Fujii; T. Fujii; T. Fukuda; M. Fukushima; D. Gorbunov; W. Hanlon; K. Hayashi; Y. Hayashi; N. Hayashida; K. Hibino; K. Hiyama; K. Honda; T. Iguchi; D. Ikeda; K. Ikuta; N. Inoue; T. Ishii; R. Ishimori; D. Ivanov; S. Iwamoto; C. C. H. Jui; K. Kadota; F. Kakimoto; O. Kalashev; T. Kanbe; K. Kasahara; H. Kawai; S....
texts
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We search for ultra-high energy photons by analyzing geometrical properties of shower fronts of events registered by the Telescope Array surface detector. By making use of an event-by-event statistical method, we derive upper limits on the absolute flux of primary photons with energies above 10^19, 10^19.5 and 10^20 eV based on the first three years of data taken.
Source: http://arxiv.org/abs/1304.5614v1
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169
Sep 21, 2013
09/13
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The JEM-EUSO Collaboration; :; J. H. Adams Jr; S. Ahmad; J. -N. Albert; D. Allard; M. Ambrosio; L. Anchordoqui; A. Anzalone; Y. Arai; C. Aramo; K. Asano; P. Barrillon; T. Batsch; J. Bayer; T. Belenguer; R. Bellotti; A. A. Berlind; M. Bertaina; P. L. Biermann; S. Biktemerova; C. Blaksley; J. Blecki; S. Blin-Bondil; J. Bluemer; P. Bobik; M. Bogomilov; M. Bonamente; M. S. Briggs; S. Briz; A. Bruno; F. Cafagna; D. Campana; J-N. Capdevielle; R. Caruso; M. Casolino; C. Cassardo; G. Castellini; O....
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Contributions of the JEM-EUSO Collaboration to the 32nd International Cosmic Ray Conference, Beijing, August, 2011.
Source: http://arxiv.org/abs/1204.5065v1
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10.0
Jun 28, 2018
06/18
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Telescope Array Collaboration; R. U. Abbasi; M. Abe; T. Abu-Zayyad; M. Allen; R. Azuma; E. Barcikowski; J. W. Belz; D. R. Bergman; S. A. Blake; R. Cady; K. Tanaka; M. Tanaka; S. B. Thomas; G. B. Thomson; P. Tinyakov; I. Tkachev; H. Tokuno; T. Tomida; S. Troitsky; Y. Tsunesada; M. J. Chae; K. Tsutsumi; Y. Uchihori; S. Udo; F. Urban; G. Vasiloff; T. Wong; R. Yamane; H. Yamaoka; K. Yamazaki; J. Yang; B. G. Cheon; K. Yashiro; Y. Yoneda; S. Yoshida; H. Yoshii; R. Zollinger; Z. Zundel; Pierre Auger...
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Joint contributions of the Pierre Auger Collaboration and the Telescope Array Collaboration to the 34th International Cosmic Ray Conference, 30 July - 6 August 2015, The Hague, The Netherlands.
Topics: Astrophysics, High Energy Astrophysical Phenomena
Source: http://arxiv.org/abs/1511.02103
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10.0
Jun 30, 2018
06/18
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The Pierre Auger; Telescope Array Collaborations; :; A. Aab; P. Abreu; M. Aglietta; E. J. Ahn; I. Al Samarai; I. F. M. Albuquerque; I. Allekotte; J. Allen; C. Di Giulio; A. Di Matteo; J. C. Diaz; M. L. Díaz Castro; F. Diogo; C. Dobrigkeit; W. Docters; J. C. D'Olivo; A. Dorofeev; Q. Dorosti Hasankiadeh; P. Allison; M. T. Dova; J. Ebr; R. Engel; M. Erdmann; M. Erfani; C. O. Escobar; J. Espadanal; A. Etchegoyen; P. Facal San Luis; H. Falcke; A. Almela; K. Fang; G. Farrar; A. C. Fauth; N. Fazzini;...
texts
eye 10
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Spherical harmonic moments are well-suited for capturing anisotropy at any scale in the flux of cosmic rays. An unambiguous measurement of the full set of spherical harmonic coefficients requires full-sky coverage. This can be achieved by combining data from observatories located in both the northern and southern hemispheres. To this end, a joint analysis using data recorded at the Telescope Array and the Pierre Auger Observatory above $10^{19}$ eV is presented in this work. The resulting...
Topics: Instrumentation and Methods for Astrophysics, High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1409.3128
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Jun 28, 2018
06/18
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IceCube Collaboration; M. G. Aartsen; K. Abraham; M. Ackermann; J. Adams; J. A. Aguilar; M. Ahlers; M. Ahrens; D. Altmann; T. Anderson; I. Ansseau; G. Golup; J. G. Gonzalez; D. Góra; D. Grant; J. C. Groh; A. Groß; C. Ha; C. Haack; A. Haj Ismail; A. Hallgren; M. Archinger; F. Halzen; B. Hansmann; K. Hanson; D. Hebecker; D. Heereman; K. Helbing; R. Hellauer; D. Hellwig; S. Hickford; J. Hignight; C. Arguelles; G. C. Hill; K. D. Hoffman; R. Hoffmann; K. Holzapfel; A. Homeier; K. Hoshina; F....
texts
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We have conducted three searches for correlations between ultra-high energy cosmic rays detected by the Telescope Array and the Pierre Auger Observatory, and high-energy neutrino candidate events from IceCube. Two cross-correlation analyses with UHECRs are done: one with 39 cascades from the IceCube `high-energy starting events' sample and the other with 16 high-energy `track events'. The angular separation between the arrival directions of neutrinos and UHECRs is scanned over. The same events...
Topics: High Energy Physics - Experiment, Astrophysics, Instrumentation and Methods for Astrophysics, High...
Source: http://arxiv.org/abs/1511.02109
