bluuebunny/crossref_metadata_2025_split huggingface dataset:
SuprimeCam Observation of Sporadic Meteors during Perseids 2004
Authors: Iye Masanori , Tanaka Mikito , Yanagisawa Masahisa , Ebizuka Noboru , Ohnishi Kouji , Hirose Chikako , Asami Naoko , Komiyama Yutaka , Furusawa Hisanori 
Published: March 2014

Abstract
We report on serendipitous findings of 13 faint meteors and 44 artificial space objects by SuprimeCam imaging observations during 2004 August 11–16. The meteors, at about 100 km altitude, and artificial satellites/debris in orbit, at 500 km altitude or higher, were clearly discriminated by their apparent defocused image sizes. We defined a peak video-rate magnitude by comparing the integrated photon counts from the brightest portion of the track traversed within 33 ms to those from a 0-mag star during the same time duration. The magnitudes thus defined for the meteors, including 1 Perseid, 1 Aquarid, and 11 sporadic meteors, were in the range 4.0 $&lt; V_{\rm vr} &lt;$ 6.4 and 4.1 $&lt; I_{\rm vr} &lt;$ 5.9. Although the spatial resolution is insufficient to resolve the source size of anything smaller than about 1 m, we developed a new estimate of the collisionally excited column diameter of these meteors. A diameter as small as a few mm was derived from their collisionally excited [O I] 5577 photon rates, meteor speed, and the volume density of the oxygen atoms at an altitude of 100 km. The actual column diameter of the radiating zone, however, could be as large as few 100 m because the excited oxygen atoms travel that distance before they emit forbidden lines in 0.7 s of its average lifetime.
Dependence of Temporal Properties on Energy in Long-Lag, Wide-Pulse Gamma-Ray Bursts
Authors: Zhang Fu-Wen , Qin Yi-Ping , Zhang Bin-Bin 
Published: March 2014

Abstract
We employed a sample by Norris et al. (2005, ApJ, 625, 324) to study the dependence of the pulse temporal properties on energy in long-lag, wide-pulse gamma-ray bursts. Our analysis shows that the pulse peak time, rise time scale, and decay time scale are power-law functions of energy, which is a preliminary report on the relationships between the three quantities and energy. The power-law indexes associated with the pulse width, rise time scale, and decay time scale are correlated, and the correlation between the indexes associated with the pulse width and the decay time scale is more obvious. In addition, we have found that the pulse peak lag is strongly correlated with the CCF lag, but the centroid lag is less correlated with the peak lag and the CCF lag. Based on these results and some previous investigations, we tend to believe that all energy-dependent pulse temporal properties may come from the joint contribution of both the hydrodynamic processes of the outflows and the curvature effect, where the energy-dependent spectral lag may be mainly dominated by the dynamic process, and the energy-dependent pulse width may be mainly determined by the curvature effect.
Detection of a Long-Extended Dust Trail Associated with Short-Period Comet 4P/Faye in 2006 Return
Authors: Sarugaku Yuki , Ishiguro Masateru , Pyo Jeonghyun , Miura Naoya , Nakada Yoshikazu , Usui Fumihiko , Ueno Munetaka 
Published: March 2014

Abstract
The longest dust trail among those so detected at optical wavelengths was found along the orbit of 4P/Faye in the 2006 return. It extended as long as 10° in the backward direction. The surface brightness increases monotonically with the distance from the nucleus between $0\rlap{.}^\circ5$ and 3°, but decreases slowly beyond 4°. The observed brightnesses of the dust trail and the tail are reasonably explained by our dust ejection model. The model shows that the dust trail is composed of cm-sized particles ejected during previous returns, and the derived power indices of the size distribution function of dust particles ejected from the nucleus ($-$3.5) and those remaining in the trail ($-$1.9) have a big difference for each other. The averaged mass-loss rate (20 kg s$^{-1}$) derived from the model is comparable to those of known IRAS dust trail comets.
Two-Dimensional Radiation-Hydrodynamic Model for Supercritical Disk Accretion Flows onto Neutron Stars
Authors: Ohsuga Ken 
Published: March 2014

Abstract
We performed two-dimensional radiation hydrodynamic simulations of supercritical accretion flows around neutron stars (NSs). In contrast with accretion flows onto black holes (BHs), we find that shell-shaped high-density regions form around the NSs, since the radiation force is enhanced in the innermost regions. The enhanced radiation force drives strong outflows above and below the disk. The mass-accretion rate onto the NS exceeds the critical rate, $L_{\rm E}/c^2$, with $L_{\rm E}$ being the Eddington luminosity. However it is about 20–30% of that onto the BH, under the condition that we employ the same mass-input rate, $\dot{M}_{\rm input}$, which is the mass injected from the outer disk boundary per unit time. The mass-outflow rate is a few-times larger in flows around NSs than in flows around BHs. The supercritical NS accretion flows mainly release the accretion energy as kinetic energy of the outflows, though the disk luminosity is predominant over the kinetic energy output rate in the BH accretion flows. The resulting velocity and mass-outflow rate of the outflows are 0.2–0.3$c$ and 150–700$L_{\rm E}/c^2$, respectively, for a mass-input rate of $3 \times 10^2\lesssim \dot{M}_{\rm input} /(L_{\rm E}/c^2)\lesssim 3\times 10^3$. This implies that the SS 433 jets can be roughly explained by supercritical accretion onto a NS. However, the collimation angle of the outflows in our simulations ($\sim 20^\circ$) is larger than that of the SS 433 jets (a few degrees).
Observational Appearance of Relativistic, Spherically Symmetric Massive Winds
Authors: Sumitomo Naoko , Nishiyama Shinji , Akizuki Chizuru , Watarai Ken-ya , Fukue Jun 
Published: March 2014

Abstract
The photon mean free path in a relativistically moving medium becomes long in the downstream direction, while short in the upstream direction. As a result, the observed optical depth, $\tau$, becomes small in the downstream direction while large in the upstream direction. Hence, if a relativistic spherical wind blows off, the optical depth depends strongly on its speed and the angle between the velocity and the line-of-sight. Abramowicz, Novikov, and Paczynski (1991, ApJ, 369, 175) examined such a relativistic wind, and found that the shape of the photosphere at $\tau=1$ appears to be convex in the nonrelativistic case, but concave for relativistic velocities. We further calculated the temperature distribution and luminosity of the photosphere both in the comoving and inertial frames. We found that the limb-darkening effect would be strongly modified in the relativistic regime. We also found that the luminosities of the photosphere become large as the wind speed increases due to relativistic effects. In addition, the luminosity in the inertial frame is higher than that in the comoving frame. These results suggest that the observed temperature and brightness in luminous objects may be overestimated when there are strong relativistic winds.
MOIRCS Deep Survey. II. Clustering Properties of $K$-Band Selected Galaxies in GOODS-North Region
Authors: Ichikawa Takashi , Suzuki Ryuji , Tokoku Chihiro , Uchimoto Yuka Katsuno , Konishi Masahiro , Yoshikawa Tomohiro , Kajisawa Masaru , Ouchi Masami , Hamana Takashi , Akiyama Masayuki , Nishimura Tetsuo , Omata Koji , Tanaka Ichi , Yamada Toru 
Published: March 2014

Abstract
We present the first measurement of clustering properties of low-mass galaxies with a stellar mass down to $M_*\sim 10^9 M_{\odot}$ at 1$\lt z \lt $4 in 24.4 arcmin$^{2}$ of the GOODS-North region with a depth of $K_\mathrm{AB}\sim$25. Luminous galaxies in the $K$-band have a larger correlation length than faint galaxies. For color-selected samples at 2$\lt z \lt$4, distant red galaxies with $J-K \gt$1.3 show a large bias of $b\sim$7.2$\pm$1.3 on scales of up to $\theta\sim$100$^{\prime\prime}$ or 3.1 comoving Mpc, while blue galaxies with 0.5$\lt J-K \lt $1.3 have a weak clustering signal on large scales, but a possible strong small-scale excess at $\theta \lt $10$^{\prime\prime}$. For massive galaxies with $M_*\gtrsim 10^{10}M_{\odot}$, we estimate the correlation length and bias to be $r_0\sim$4.5$h^{-1}$Mpc and $b=$1.9–3.5, which are much larger than those of low-mass ($M_*\sim$10$^9-10^{10}M_{\odot}$) galaxies. The comparison of our measurements with analytic CDM models constrains the properties of hosting dark halos, and indicates that the low-mass galaxies would be progenitors of galaxies with a typical luminosity of $L\lesssim L_*$ in the local Universe. The blue galaxies in low-mass samples are more strongly clustered in more massive halos with higher occupation numbers than low-mass red galaxies. This fact suggests an environment effect due to the halo mass on the star-formation activity at high-$z$.
An Orbital Period Investigation of the W UMa-Type Binary Y Sextantis
Authors: He Jia-Jia , Qian Sheng-Bang 
Published: March 2014

Abstract
Four charge-coupled device (CCD) photometric times of light minimum of the overcontact binary Y Sex obtained from 2004 to 2007 are presented. It has been discovered that the light curve of Y Sex is variational. Combining the present times of light minimum with values collected from the literature, we investigated the orbital period changes of the system. It has been found that there may exist two cyclic period oscillations in the $O-C$ diagram of Y Sex. One oscillates at a period of 51.22 yr with an amplitude of 0.0218 d, and the other changes at a period of 32.10 yr with an amplitude of 0.0100 d. The period oscillations can be explained either by the light-time effect via the presence of an unseen third body and an unseen fourth body or by magnetic-activity cycles of the components.
Survey for a Small Asteroid Population in the Cosmic Evolution Survey Field
Authors: Terai Tsuyoshi , Itoh Yoichi , Mukai Tadashi 
Published: March 2014

Abstract
We searched for small main-belt asteroids in the Cosmic Evolution Survey (COSMOS) field using the Subaru Prime Focus Camera (Suprime-Cam). The ecliptic latitude of the region is about $-$10$^{\circ}$. Using a method we developed to detect moving objects from two images, we detected 202 moving objects with a limiting magnitude of $i^{\prime} =$ 23.8 mag in 1.7 deg$^2$. Most of them are sub-km asteroid candidates. The number density is 122 deg$^{-2}$, less than half of that in the ecliptic. The slope of the cumulative size distribution is 1.30$\pm$0.05 for asteroids with a diameter of 0.5–2 km, consistent with that of sub-km asteroids in the ecliptic derived from a previous survey.
Instability of Population III Black Hole Accretion Disks
Authors: Ohsuga Ken , Susa Hajime , Uchiyama Yosuke 
Published: March 2014

Abstract
We investigated the stability of black hole accretion disks in a primordial environment (POP III disks for short), by solving the vertical structure of optically thick disks, including convective energy transport, and by employing a one-zone model for optically thin isothermal disks. Because of the absence of metals in POP III disks, we find significant differences in stability associated with ionization between POP III disks and the disks of solar metallicity. An unstable branch in S-shaped equilibrium curves on the $\dot{M}$–$\Sigma$ (mass accretion rate–surface density) plane extends to a larger surface density compared with the case of disks of solar metallicity. The resulting equilibrium loci indicate that quasi-periodic oscillations in luminosity can also be driven in POP III disks, and their maximal luminosity is typically by an order of magnitude larger than that of the disks of solar metallicity. Such a strong outburst of POP III disks can be observed by future huge telescopes, in the case that the mass is supplied onto the disks at the Bondi accretion rates in typical virialized small dark halos.
A Possible Structure of the Magnetic Field in Solar Filaments Obtained by Flux Emergence
Authors: Magara Tetsuya 
Published: March 2014

Abstract
We report a result, that the emergence of a subsurface magnetic field naturally reproduces the feature of the global magnetic configuration observed in solar filaments. This was obtained by performing a three-dimensional simulation of a twisted flux tube that emerges in the shape of a multi-$\Omega$-loop in a highly stratified solar atmosphere, extending from the subsurface layer to the corona. One of the key findings is that a kinking of the twisted flux tube occurs at the site of a linkage between adjacent $\Omega$-loops. This develops a magnetic structure that has remarkable similarities to the structure of a filament, in that the inner part of the twisted flux tube can be applied to the main body of a filament, while the outer part is reminiscent of observations of filament feet and a coronal arcade overlying the main body of a filament. Based on the result, we concluded that the orientation of filaments observed on the Sun may have its origin in the handedness of a twisted magnetic field below the solar surface.
Evidence for Solar-Wind Charge-Exchange X-Ray Emission from the Earth’s Magnetosheath
Authors: Fujimoto Ryuichi , Mitsuda Kazuhisa , McCammon Dan , Takei Yoh , Bauer Michael , Ishisaki Yoshitaka , Porter F. Scott , Yamaguchi Hiroya , Hayashida Kiyoshi , Yamasaki Noriko Y. 
Published: March 2014

Abstract
We report an apparent detection of the C VI 4p to 1s transition line at 459 eV, during a long-term enhancement (LTE) in the Suzaku north ecliptic pole observation of 2005 September 2. The observed line intensity is comparable to that of the C VI 2p to 1s line at 367 eV. This is strong evidence for the charge-exchange process. In addition, O VII, O VIII, Ne X, and Mg XI lines showed clear enhancements. There are also features in the 750–900–eV range that could be due to some combination of Fe L lines, higher order transitions of O VIII (3p to 1s and 6p to 1s), and a Ne IX line. From the correlation of the X-ray intensity with the solar-wind flux on time scales of about half a day, and from the short-term ($\sim 10 \,\mathrm{minutes}$) variations of the X-ray intensity, these lines most likely arise from solar-wind heavy ions interacting with neutral material in the Earth’s magnetosheath. A hard power-law component is also necessary to explain the LTE spectrum. Its origin is not yet known. Our results indicate that solar activity can significantly contaminate Suzaku cosmic X-ray spectra below $\sim 1 \,\mathrm{keV}$. Recommendations are provided for recognizing such contamination in observations of extended sources.
X-Ray Spectral Study of the Extended Emission, ‘the Cap’, Located 11.6 kpc above the Disk of M82
Authors: Tsuru Takeshi Go , Ozawa Midori , Hyodo Yoshiaki , Matsumoto Hironori , Koyama Katsuji , Awaki Hisamitsu , Fujimoto Ryuichi , Griffiths Richard , Kilbourne Caroline , Matsushita Kyoko , Mitsuda Kazuhisa , Ptak Andrew , Ranalli Piero , Yamasaki Noriko Y. 
Published: March 2014

Abstract
The extended X-ray emission from ‘the Cap’ region, located $11{}^{\prime }$ (11.6 kpc) above the disk of the starburst galaxy M82, has been observed with Suzaku and XMM-Newton. Owing to the good energy resolution and the large collecting area of the XIS on Suzaku, combined with similar properties of the EPIC instrument on XMM-Newton, we have clearly detected K-shell emission lines from O VII, O VIII, Ne X, Mg XI, Mg XII, Sr XIII, and the Fe L complex. Two optically thin thermal plasma components are required to fit the observed X-ray spectra. We have determined the metal abundances of O, Ne, Mg, Si, and Fe in this region for the first time. Their metal abundance ratios agree well with those of metal-poor stars and the model prediction of metals synthesized by type-II supernovae, but they are not consistent with the metallicities of type-Ia supernovae. This result is support for the idea that the origin of the metals in the Cap is type-II supernova explosions occurring in the starburst regions in the M82 galaxy. We discuss the possible contribution from sputtered dust grains to the metals in the Cap. An emission line consistent with the C VI transition of $n=4$ to 1 at 0.459 keV has been marginally detected, although it is not statistically significant at the 99% confidence level; the presence of this line would suggest charge-exchange processes in the Cap.
Revealing the High Energy Emission from the Obscured Seyfert Galaxy MCG−5–23–16 with Suzaku
Authors: Reeves James N. , Awaki Hisamitsu , Dewangan Gulab C. , Fabian Andy C. , Fukazawa Yasushi , Gallo Luigi , Griffiths Richard , Inoue Hajime , Kunieda Hideyo , Markowitz Alex , Miniutti Giovanni , Mizuno Tsunefumi , Mushotzky Richard , Okajima Takashi , Ptak Andy , Takahashi Tadayuki , Terashima Yuichi , Ushio Masayoshi , Watanabe Shin , Yamasaki Tomonori , Yamauchi Makoto , Yaqoob Tahir 
Published: March 2014

Abstract
We report on a 100 ks Suzaku observation of the bright, nearby ($z=0.008486$) Seyfert 1.9 galaxy MCG $-$5–23–16. The broad-band (0.4–100 keV) X-ray spectrum allows us to determine the nature of the high energy emission with little ambiguity. The X-ray continuum consists of a cutoff power-law of photon index $\Gamma=1.9$, absorbed through Compton-thin matter of column density $N_{\mathrm{H}} = 1.6 \times 10^{22} \,\mathrm{cm}^{-2}$. A soft excess is observed below 1 keV and is likely a combination of emission from scattered continuum photons and distant photoionized gas. The iron K line profile is complex, showing narrow neutral iron $\mathrm{K}\alpha$ and $\mathrm{K}\beta$ emission, as well as a broad line which can be modeled by a moderately inclined accretion disk. The line profile shows either the disk is truncated at a few tens of gravitational radii, or the disk emissivity profile is relatively flat. A strong Compton reflection component is detected above 10 keV, which is best modeled by a combination of reflection off distant matter and the accretion disk. The reflection component does not appear to vary. The overall picture is that this Seyfert 1.9 galaxy is viewed at moderate ($\sim 50^\circ$) inclination through Compton-thin matter at the edge of a Compton-thick torus covering $\sim 2\pi$ steradians, consistent with unified models.
Near-Infrared and Mid-Infrared Spectroscopy with the Infrared Camera (IRC) for AKARI
Authors: Ohyama Youichi , Onaka Takashi , Matsuhara Hideo , Wada Takehiko , Kim Woojung , Fujishiro Naofumi , Uemizu Kazunori , Sakon Itsuki , Cohen Martin , Ishigaki Miho , Ishihara Daisuke , Ita Yoshifusa , Kataza Hirokazu , Matsumoto Toshio , Murakami Hiroshi , Oyabu Shinki , TanabÉ Toshihiko , Takagi Toshinobu , Ueno Munetaka , Usui Fumio , Watarai Hidenori , Pearson Chris P. , Takeyama Norihide , Yamamuro Tomoyasu , Ikeda Yuji 
Published: March 2014

Abstract
The Infrared Camera (IRC) is one of the two instruments on board the AKARI satellite, In addition to deep imaging from 1.8 to 26.5 $\mu$m for the pointed observation mode of the AKARI, it has a spectroscopic capability in its spectral range. By replacing the imaging filters by transmission-type dispersers on the filter wheels, it provides low-resolution ($\lambda$/$\delta \lambda \sim$ 20–120) spectroscopy with slits, or in a wide imaging field-of-view (approximately 10$\;\times\;$10). The IRC spectroscopic mode is unique for space infrared missions in that it has the capability to perform sensitive wide-field spectroscopic surveys in the near-and mid-infrared wavelength ranges. This paper describes the specifications of the IRC spectrograph and its in-orbit performance.
In-Orbit Focal Adjustment of the AKARI Telescope with Infrared Camera (IRC) Images
Authors: Kaneda Hidehiro , Kim Woojung , Onaka Takashi , Wada Takehiko , Ita Yoshifusa , Sakon Itsuki , Takagi Toshinobu 
Published: March 2014

Abstract
AKARI, currently in space, carries onboard a cryogenically cooled light-weight telescope with silicon carbide mirrors. The wavefront error of the AKARI telescope, obtained in laboratory measurements at 9 K, showed that the expected in-orbit imaging performance was diffraction-limited at a wavelength of 6.2 $\mu$m. The AKARI telescope has a function of focus adjustment by shifting the secondary mirror in parallel to the optical axis. On the 4th day after jettison of the cryostat aperture lid in orbit, we observed a star with the Infrared Camera (IRC) onboard AKARI. Since the initial star images observed in the near-infrared (NIR) bands were significantly blurred, we twice moved the secondary mirror for a focal adjustment based on the results of model analyses as well as data analyses of NIR band images. As a consequence, we successfully adjusted the focus of the telescope. The thus-obtained in-orbit imaging performance for the AKARI telescope is diffraction-limited at a wavelength of 7.3 $\mu$m, slightly degraded from that expected from laboratory measurements.
Infrared Camera (IRC) Deep Survey in the Performance-Verification Phase
Authors: Wada Takehiko , Oyabu Shinki , Ita Yoshifusa , Matsuhara Hideo , Pearson Chris P. , Onaka Takashi , Ohyama Youichi , Usui Fumihiko , Fujishiro Naofumi , Ishihara Daisuke , Kataza Hirokazu , Kim Woojung , Matsumoto Toshio , Murakami Hiroshi , Sakon Itsuki , TanabÉ Toshihiko , Takagi Toshinobu , Uemizu Kazunori , Ueno Munetaka , Watarai Hidenori 
Published: March 2014

Abstract
We report on the first results of a near- and mid-infrared deep survey with the Infrared Camera (IRC) onboard AKARI in the performance-verification phase. Simultaneous observations by the Near-InfraRed (NIR), Mid-InfraRed Short (MIR-S), and Mid-InfraRed Long (MIR-L) channels of the IRC with effective integration times of 4529, 4908, and 4417 seconds at 3, 7, and 15$\mu $m, covering 86.0, 70.3, and 77.3 arcmin$^2$ area, detected 955, 298, and 277 sources, respectively. The 5 $\sigma$ detection limits of the survey are 6.0, 31.5, and 71.2$\mu $Jy and the 50% completeness limit are 24.0, 47.5, and 88.1$\mu $Jy at 3, 7, and 15$\mu $m, respectively. Observation are limited by source confusion at 3$\mu $m. We have confirmed the turnover in the 15$\mu $m differential source counts around 400$\mu $Jy, previously detected by surveys with the Infrared Space Observatory. The faint end of 15$\mu $m raw source counts agrees with those from deep surveys in the GOODS fields, carried out with the Spitzer IRS peak up imager and predictions of current galaxy evolution models. These results indicate that deep surveys with comprehensive wavelength coverage at mid-infrared wavelength are very important to investigate the evolution of infrared galaxies at high redshifts.