bluuebunny/crossref_metadata_2025_split huggingface dataset:
Suzaku Observations of the Great Annihilator and the Surrounding Diffuse Emissions
Authors: Nakashima Shinya , Nobukawa Masayoshi , Tsuru Takeshi Go , Koyama Katsuji , Uchiyama Hideki 
Published: March 2014

Abstract
We report the Suzaku observations of 1E 1740.7$-$2942, a black hole candidate called the “Great Annihilator” (GA). The high-quality spectrum of Suzaku provides the severest constraints on the parameters of the GA. Two clumpy structures are found around the GA in the line images of FeI K$\alpha$ at 6.4 keV and SXV K$\alpha$ at 2.45 keV. One clump, named M 359.23$-$0.04, exhibits the 6.4-keV line with an equivalent width of $\sim\ $1.2 keV, and is associated with a molecular cloud in the radio CS ($J =$ 1–0) map. Thus, the 6.4-keV line from M 359.23$-$0.04 is likely due to X-ray fluorescence irradiated by an external X-ray source. The irradiating X-rays would be either a past flare of Sagittarius A$^\ast$ or a bright nearby source, the GA. The other clump, named G 359.12$-$0.05, is associated with the radio supernova remnant candidate G 359.07$-$0.02. We therefore propose that G 359.12$-$0.05 is an X-ray counterpart of G 359.07$-$0.02. G 359.12$-$0.05 has a thin thermal plasma spectrum with a temperature of kT$\sim\ $ 0.9 keV. The plasma parameters of G 359.12$-$0.05 are consistent with those of a single supernova remnant in the Galactic center region.
Spitzer Space Telescope Constraint on the Stellar Mass of a z = 6.96 Lyα Emitter
Authors: Ota Kazuaki , Ly Chun , Malkan Matthew A. , Motohara Kentaro , Hayashi Masao , Shimasaku Kazuhiro , Morokuma Tomoki , Iye Masanori , Kashikawa Nobunari , Hattori Takashi 
Published: March 2014

Abstract
We obtained mid-infrared 3.6 and 4.5$\ \mu$m imaging of a $z =$ 6.96 Ly$\alpha $ emitter (LAE), IOK-1, discovered in the Subaru Deep Field, using Spitzer Space Telescope Infrared Array Camera observations. After removal of a nearby bright source, we found that IOK-1 is not significantly detected in any of these infrared bands to $m_{3.6\mu{\rm m}} \sim$ 24.00 and $m_{4.5\mu{\rm m}} \sim$ 23.54 at 3$\ \sigma$. Fitting population synthesis models to the spectral energy distribution consisting of the upper limit fluxes of the optical-to-infrared non-detection images and fluxes in detection images, we constrained the stellar mass, $M_\ast$, of IOK-1. This LAE could have either a mass as low as $M_\ast \lesssim$ 2–9 $\times$ 10$^{8}\ M_{\odot}$ for young age ($\lesssim$10 Myr) and low dust reddening ($A_V \sim$ 0) or a mass as large as $M_\ast \lesssim$ 1–4 $\times$ 10$^{10}\ M_{\odot}$ for either old age ($ \gt \ $100 Myr) or high dust reddening ($A_V \sim$ 1.5). This would be within the range of masses of $z \sim$ 3–6.6 LAEs studied to date, $\sim$10$^6$–10$^{10}\ M_{\odot}$. Hence, IOK-1 is not a particularly unique galaxy with extremely high mass or low mass, but is similar to one of the LAEs seen at later epochs.
Transiting Extrasolar Planet with a Companion: Effects of Orbital Eccentricity and Inclination
Authors: Sato Masanao , Asada Hideki 
Published: March 2014

Abstract
Continuing work initiated in an earlier publication (Sato & Asada, 2009, PASJ, 61, L29), we consider light curves influenced by the orbital inclination and eccentricity of a companion in orbit around a transiting extrasolar planet (in a planet–satellite system or a hypothetical true binary). We show that the semimajor axis, eccentricity and inclination angle of a ‘moon’ orbit around the host planet can be determined by the transit method alone. For this purpose, we present a formulation for the parameter determinations in a small-eccentricity approximation as well as in the exact form. As a result, the semimajor axis is expressed in terms of observables, such as brightness changes, transit durations and intervals in light curves. We also discuss a narrow region of parameters that produce a mutual transit by an extrasolar satellite.
Oxygen and Neon Abundances of B-Type Stars in Comparison with the Sun
Authors: Takeda Yoichi , Kambe Eiji , Sadakane Kozo , Masuda Seiji 
Published: March 2014

Abstract
To revisit the long-standing problem of a possible inconsistency concerning the oxygen composition in the current Galactic gas and in the solar atmosphere (i.e., the former being appreciably lower by $\sim\ $0.3 dex), apparently contradicting the Galactic chemical evolution, we carried out oxygen abundance determinations for 64 mid- through late-B stars by using the O I 6156–8 lines while taking into account the non-LTE effect, and compared them with the solar O abundance established in the same manner. The resulting mean oxygen abundance was $\langle A^{\rm O} \rangle =$ 8.71 ($\pm$ 0.06), which means that [O$/$H] (star $-$ Sun differential abundance) is $\sim-$0.1, the difference being less significant than previously thought. Moreover, since the 3D correction may further reduce the reference solar oxygen abundance (8.81) by $\sim\ $0.1 dex, we conclude that the photospheric O abundances of these B stars are almost the same as that of the Sun. We also determined the non-LTE abundances of neon for sample B stars from Ne I 6143/6163 lines to be $\langle A^{\rm Ne} \rangle =$ 8.02 ($\pm$ 0.09), leading to an Ne-to-O ratio of $\sim\ $0.2, consistent with recent studies. This excludes the possibility of a considerably high Ne$/$O ratio once proposed as a solution to the confronted solar model problem.
The AMANOGAWA-2SB Galactic Plane Survey I. Data on the Galactic Equator
Authors: Yoda Takahiro , Handa Toshihiro , Kohno Kotaro , Nakajima Taku , Kaiden Masahiro , Yonekura Yoshinori , Ogawa Hideo , Morino Jun-ichi , Dobashi Kazuhito 
Published: March 2014

Abstract
Using a waveguide-type sideband-separating receiver (2SB receiver) on the Tokyo-NRO 60-cm telescope (renamed the AMANOGAWA telescope), we carried out simultaneous observations in the $^{12}$CO ($J =$ 2–1) and $^{13}$CO ($J =$ 2–1) lines over the galactic plane $l =$ 10$^\circ$–245$^\circ$ along $b =$ 0$^\circ$ with a 3$'\!\!.$75 grid. Using the $^{12}$CO ($J =$ 1–0) data of Dame et al. (2001, ApJ, 547, 792), who used a beam size almost the same as ours, we show $^{12}$CO ($J =$ 2–1)$/^{12}$CO ($J =$ 1–0) and $^{13}$CO ($J =$ 2–1)$/^{12}$CO ($J =$ 2–1) intensity ratios on the $l$–$v$ map and the intensity correlations among the $^{12}$CO ($J =$ 2–1), $^{13}$CO ($J =$ 2–1), and $^{12}$CO ($J =$ 1–0) lines. As a result, a linear correlation between $^{12}$CO ($J =$ 2–1) and $^{12}$CO ($J =$ 1–0) and a curved correlation between $^{12}$CO ($J =$ 2–1) and $^{13}$CO ($J =$ 2–1), as produced by most of the data, have been found. We investigated these correlations with simple radiative transfer equations to ascertain a number of restrictions on the physical quantities of molecular gas on a galactic scale.
Identification of CXOU J171405.7−381031 as a New Magnetar with XMM-Newton
Authors: Sato Takuro , Bamba Aya , Nakamura Ryoko , Ishida Manabu 
Published: March 2014

Abstract
We observed the 3.8 s pulsar CXOU J171405.7$-$381031 with XMM-Newton, and discovered a significant $\dot P$ of 6.40$\ \pm\ $0.05 $\times$ 10$^{-11}\ $s s$^{-1}$ from this source for the first time, with the aid of archival Chandra data. The characteristic age (950 yr), the magnetic field strength (5 $\times$ 10$^{14}\ $G), and the spin-down luminosity (4.5 $\times$ 10$^{34}\ $erg s$^{-1}$) derived from $P$ and $\dot P$ lead us to conclude that CXOU J171405.7$-$381031 should be identified as a new magnetar. The obtained characteristic age indicates that CXOU J171405.7$-$381031 is the youngest among all known anomalous X-ray pulsars, and is consistent with the age estimated from the thermal X-rays of the associated supernova remnant. The ratio between the 2–10 keV luminosity and the spin-down luminosity is almost unity, which implies that CXOU J171405.7$-$381031 is the key source to connect magnetars with traditional radio pulsars.
New Panoramic View of 12CO and 1.1 mm Continuum Emission in the Orion A Giant Molecular Cloud. I. Survey Overview and Possible External Triggers of Star Formation
Authors: Shimajiri Yoshito , Kawabe Ryohei , Takakuwa Shigehisa , Saito Masao , Tsukagoshi Takashi , Momose Munetake , Ikeda Norio , Akiyama Eiji , Austermann Jason E. , Ezawa Hajime , Fukue Kei , Hiramatsu Masaaki , Hughes David , Kitamura Yoshimi , Kohno Kohtaro , Kurono Yasutaka , Scott Kimberly S. , Wilson Grant W. , Yoshida Atsumasa , Yun Min S. 
Published: March 2014

Abstract
We present new, wide, and deep images in the 1.1 mm continuum and the $^{12}$CO ($J$$=$ 1–0) emission toward the northern part of the Orion A Giant Molecular Cloud (Orion-A GMC). The 1.1 mm data were taken with the AzTEC camera mounted on the Atacama Submillimeter Telescope Experiment (ASTE) 10 m telescope in Chile, and the $^{12}$CO ($J$$=$ 1–0) data were with the 25 beam receiver (BEARS) on the Nobeyama Radio Observatory (NRO) 45 m telescope in the On-The-Fly (OTF) mode. The present AzTEC observations are the widest (1$^\circ\!\!\!.$7 $\times$ 2$^\circ\!\!\!.$3, corresponding to 12 pc $\times$ 17 pc) and the highest-sensitivity ($\sim\ $9 mJy beam$^{-1}$) 1.1 mm dust-continuum imaging of the Orion-A GMC with an effective spatial resolution of $\sim\ $40$”$. The $^{12}$CO ($J$$=$ 1–0) image was taken over the northern 1$^\circ\!\!\!.$2 $\times$ 1$^\circ\!\!\!.$2 (corresponding 9 pc $\times$ 9 pc) area with a sensitivity of 0.93 K in $T_{\rm MB}$, a velocity resolution of 1.0 km s$^{-1}$, and an effective spatial resolution of 21$”$. With these data, together with the MSX 8$\ \mu$m, Spitzer 24$\ \mu$m, and the 2MASS data, we have investigated the detailed structure and kinematics of molecular gas associated with the Orion-A GMC, and have found evidence for interactions between molecular clouds and the external forces that may trigger star formation. Two types of possible triggers were revealed: (1) Collisions of the diffuse gas on the cloud surface, particularly at the eastern side of the OMC-2/3 region, and (2) Irradiation of UV on the pre-existing filaments and dense molecular cloud cores. Our wide-field and high-sensitivity imaging has provided the first comprehensive view of the potential sites of triggered star formation in the Orion-A GMC.
High Excitation Molecular Gas in the Galactic Center Loops; 12CO (J = 2–1 and J = 3–2) Observations
Authors: Kudo Natsuko , Torii Kazufumi , Machida Mami , Davis Timothy A. , Tsutsumi Kazuki , Fujishita Motusuji , Moribe Nayuta , Yamamoto Hiroaki , Okuda Takeshi , Kawamura Akiko , Mizuno Norikazu , Onishi Toshikazu , Maezawa Hiroyuki , Mizuno Akira , Tanaka Kunihiko , Yamaguchi Nobuyuki , Ezawa Hajime , Takahashi Kunio , Nozawa Satoshi , Matsumoto Ryoji , Fukui Yasuo 
Published: March 2014

We have carried out $^{12}$CO ($J$ $=$ 2–1) and $^{12}$CO ($J$ $=$ 3–2) observations at spatial resolutions of 1.0–3.8 pc toward the entirety of loops 1 and 2 and part of loop 3 in the Galactic center with NANTEN2 and ASTE. These new results have revealed detailed distributions of the molecular gas and the line intensity ratio of the two transitions, $R_{3-2/2-1}$. In the three loops, $R_{3-2/2-1}$ is in a range from 0.1 to 2.5 with a peak at $\sim\ $0.7, while that in the disk molecular gas is in a range from 0.1 to 1.2 with a peak at 0.4. This supports that the loops are more highly excited than the disk molecular gas. An LVG analysis of three transitions, $^{12}$CO $J$ $=$ 3–2 and 2–1 and $^{13}$CO $J$ $=$ 2–1, toward six positions in loops 1 and 2 shows that the density and temperature are in the range 10$^{2.2}$–10$^{4.7}\ $cm$^{-3}$ and 15–100 K or higher, respectively. Three regions, extended by 50–100 pc in the loops, tend to have higher excitation conditions, as characterized by $R_{3-2/2-1}$ greater than 1.2. The highest ratio of 2.5 is found in the most developed foot points between loops 1 and 2. This is interpreted that the foot points indicate strongly shocked conditions, as inferred from their large linewidths of 50–100 km s$^{-1}$, confirming a suggestion by Torii et al. (2010, PASJ, 62, 675). The other two regions outside the foot points suggest that the molecular gas is heated up by some additional heating mechanisms, possibly including magnetic reconnection. A detailed analysis of four foot points has shown a U shape, an L shape or a mirrored-L shape in the $b$–$v$ distribution. It is shown that a simple kinematical model that incorporates global rotation and expansion of the loops is able to explain these characteristic shapes.
New Distance and Revised Natures of High-Mass Star Formation in G5.89–0.39
Authors: Motogi Kazuhito , Sorai Kazuo , Habe Asao , Honma Mareki , Kobayashi Hideyuki , Sato Katsuhisa 
Published: March 2014

Abstract
We report on astrometric observations of the 22 GHz H$_{2}$O masers in the high-mass star-forming region G5.89$-$0.39 with VERA (VLBI Exploration of Radio Astrometry). A newly derived distance of 1.28$^{+0.09}_{\-0.08}$ kpc is the most precise, and is significantly nearer than the previous values. We revised the physical parameters and reconsidered the nature of G5.89$-$0.39 based on the new distance as follows: (1) The ionizing star of the ultra compact (UC) H II region is a late O-type (O8–O8.5) zero age main sequence (ZAMS) star, consistent with previously established limits based on its infrared spectral line emission. (2) Crescent-like maser alignment at the position of the O-type ZAMS star may trace an accretion disk (or its remnant), which suggests that the star is still young, and before complete evaporation of circumstellar materials. (3) Although the revised mass for the east-west outflow has been reduced, it is still quite large (100 $M_\odot$), which indicates that a significant fraction of the mass is entrained material, and that the dynamical age significantly underestimates the actual outflow age. Our newly-derived distance emphasizes that G5.89$-$0.39 is one of the nearest targets to investigate ongoing high-mass star formation and evolution in a compact cluster containing a young O-type star.
Spatially Extended [P II] 1.188 μm and [Fe II] 1.257 μm Emission Lines in a Nearby Seyfert Galaxy NGC1068 Observed with OAO/ISLE
Authors: Hashimoto Tetsuya , Nagao Tohru , Yanagisawa Kenshi , Matsuoka Kenta , Araki Nobuo 
Published: March 2014

Abstract
We present $J$-band long-slit spectroscopic observation of NGC 1068 classified as a Seyfert 2 galaxy. $J$-band observations with OAO/ISLE provide clear detection of spatially extended [Fe II] 1.257 $\mu$m and [P II] 1.188 $\mu$m lines. We found that [Fe II] 1.257 $\mu$m$/$[P II] 1.188 $\mu$m increases with distance from a central continuum peak. Observed line ratios around the nucleus (continuum peak) are consistent with a typical value expected from photoionization models, while the ratios at 3$”$–4$”$ (210–280 pc) east and west of the nucleus are slightly higher than this. In the off nucleus region of NGC 1068 we also found a possible association between [Fe II] 1.257 $\mu$m$/$[P II] 1.188 $\mu$m and the radio continuum. This suggests a mild contribution of shock ionization induced by a radio jet outside nucleus while photoionization by the central energy source is dominant near the nucleus.
Soft and Hard X-Ray Emissions from the Anomalous X-Ray Pulsar 4U 0142+61 Observed with Suzaku
Authors: Enoto Teruaki , Makishima Kazuo , Nakazawa Kazuhiro , Kokubun Motohide , Kawaharada Madoka , Kotoku Jun'ichi , Shibazaki Noriaki 
Published: March 2014

The anomalous X-ray pulsar 4U 0142$+$61 was observed with Suzaku on 2007 August 15 for a net exposure of $\sim\ $100 ks, and was detected in a 0.4 to $\sim\ $70 keV energy band. The intrinsic pulse period was determined to be 8.68878$\ \pm\ $0.00005 s, in agreement with an extrapolation from previous measurements. The broadband Suzaku spectra enabled a first simultaneous and accurate measurement of the soft and hard components of this object by a single satellite. The former can be reproduced by two blackbodies, or slightly better by a resonant cyclotron scattering model. The hard component can be approximated by a power-law of photon index of $\Gamma_{\rm h}$ $\sim\ $ 0.9 when the soft component is represented by the resonant cyclotron scattering model, and its high-energy cutoff is constrained as $\gt\ $180 keV. Assuming an isotropic emission at a distance of 3.6 kpc, the unabsorbed 1–10 keV and 10–70 keV luminosities of the soft and hard components were calculated to be 2.8 $\times$ 10$^{35}\ $erg s$^{-1}$ and 6.8 $\times$ 10$^{34}\ $erg s$^{-1}$, respectively. Their sum becomes $\sim\ $10$^3$ times as large as the estimated spin-down luminosity. On a time scale of 30 ks, the hard component exhibited evidence of variations either in its normalization or pulse shape.
Prominent Polarized Flares of the Blazars AO 0235164 and PKS 1510089
Authors: Sasada Mahito , Uemura Makoto , Fukazawa Yasushi , Kawabata Koji S. , Ikejiri Yuki , Itoh Ryosuke , Yamanaka Masayuki , Sakimoto Kiyoshi , Ohsugi Takashi , Yoshida Michitoshi , Sato Shuji , Kino Masaru 
Published: March 2014

Abstract
We report on multi-band photometric and polarimetric observations of the blazars AO 0235$+$164 and PKS 1510$-$089. These two blazars were active in 2008 and 2009, respectively. In these active states, prominent short flares were observed in both objects, having amplitudes of $\gt$1mag within 10d. The $V$$-$$J$ color became bluer when the objects were brighter in these flares. On the other hand, the color of PKS 1510$-$089 exhibited a trend that it became redder when it was brighter, except for its prominent flare. This redder-when-brighter trend can be explained by the strong contribution of thermal emission from an accretion disk. The polarization degree increased at the flares, and reached $\gt$25% at the maxima. We compared these flares in AO 0235$+$164 and PKS 1510$-$089 with other short flares that were detected by our monitoring of 41 blazars. Those two flares had one of the largest variation amplitudes in both flux and polarization degree. Furthermore, we found a significant positive correlation between the amplitudes of the flux and the polarization degree in short flares. It indicates that the short flares originate from the region where the magnetic field is aligned.
Effect of Magnetic Braking on Circumstellar Disk Formation in a Strongly Magnetized Cloud
Authors: Machida Masahiro N. , Inutsuka Shu-ichiro , Matsumoto Tomoaki 
Published: March 2014

Abstract
Using resistive magnetohydrodynamics simulation, we consider circumstellar disk formation in a strongly magnetized cloud. As the initial state, an isolated cloud core embedded in a low-density interstellar medium with a uniform magnetic field was adopted. The cloud evolution was calculated until almost all gas inside the initial cloud fell onto either the circumstellar disk or a protostar, and a part of the gas was ejected into the interstellar medium by the protostellar outflow driven by the circumstellar disk. In the early main accretion phase, the disk size is limited to $\sim\ $10 AU because the angular momentum of the circumstellar disk is effectively transferred by both magnetic braking and the protostellar outflow. In the later main accretion phase, however, the circumstellar disk grows rapidly and exceeds $\gtrsim\ $100 AU by the end of the main accretion phase. This rapid growth of the circumstellar disk is caused by depletion of the infalling envelope, while magnetic braking is effective when the infalling envelope is more massive than the circumstellar disk. The infalling envelope cannot brake the circumstellar disk when the latter is more massive than the former. In addition, the protostellar outflow weakens and disappears in the later main accretion phase, because the outflow is powered by gas accretion onto the circumstellar disk. Although the circumstellar disk formed in a magnetized cloud is considerably smaller than that in an unmagnetized cloud, a circumstellar disk exceeding 100 AU can form even in a strongly magnetized cloud.
Properties of Dust and PAHs in the Hot Plasma of the Elliptical Galaxy NGC 4125 Revealed with AKARI and Spitzer Space Telescope
Authors: Kaneda Hidehiro , Ishihara Daisuke , Onaka Takashi , Suzuki Toyoaki , Mori Tatsuya , Oyabu Shinki , Yamagishi Mitsuyoshi 
Published: March 2014

Abstract
We present the spatial distributions of dust and polycyclic aromatic hydrocarbons (PAHs) in the elliptical galaxy NGC 4125, revealed by AKARI and Spitzer. NGC 4125 is relatively bright in dust and PAH emision for elliptical galaxies, although it certainly possesses diffuse interstellar hot plasma, indicated by the high spatial resolution X-ray data of Chandra. We investigate how the dust and PAHs interact with the X-ray plasma or avoid the interaction by comparing their spatial distributions. We find that the distributions of the PAHs and dust are different from each other, both showing a significant deviation from a smooth stellar distribution. The PAH emission predominantly comes from a dust lane, a compact dense molecular gas region in the galactic center, where the PAHs are likely to have been protected from the interaction with the X-ray plasma. The dust emission has more extended structures, similar to the distribution of the X-ray plasma, suggesting their interaction to some extent. We also discuss a possible origin of the dust and PAHs in the galaxy.
Sagittarius A Molecular Cloud Complex in H13CO+ and Thermal SiO Emission Lines
Authors: Tsuboi Masato , Tadaki Ken-ichi , Miyazaki Atsushi , Handa Toshihiro 
Published: March 2014

Abstract
We present results of a high-resolution wide-field mapping observation of the Sagittarius A (Sgr A) molecular cloud complex in H$^{13}$CO$^+$ $J$ $=$ 1–0 and thermal SiO $J$ $=$ 2–1 emission lines with the 25-beam receiver of the 100 GHz band operating on the Nobeyama Radio Observatory 45-m telescope. The mapping area covers a 0$^\circ\!\!\!.$5 $\times$ 0$^\circ\!\!\!.$5 area involving several named molecular clouds, for example GCM$-$0.02$-$0.07, GCM$-$0.13$-$0.08, GCM 0.11$-$0.11, the Sickle molecular cloud, the Arched filaments molecular cloud, and so on. The data have an effective angular resolution of 26$''$. The H$^{13}$CO$^+$ emission line is a famous tracer of molecular gas mass because the line is optically thin, even in the Galactic center region, and is not emphasized by shock. The emission line presents a clumpy distribution of the molecular cloud. The averaged fractional abundance in the Sgr A complex is $N$(H$^{13}$CO$^+$)$/N_{\mathrm{H_2}}$ $\simeq$ (1.8$\ \pm\ $0.4) $\times$ 10$^{-11}$, comparing the LTE mass and the virial theorem mass. The SiO emission line is a famous and reliable tracer of shocked molecular gas. We find many molecular clouds that are remarkable only in the SiO emission line. Such molecular clouds have a large velocity width of up to 60 km s$^{-1}$. The brightness temperature ratio is up to $T_{\mathrm{B}}$(SiO)$/T_{\mathrm{B}}$(H$^{13}$CO$^+$) $\lesssim$ 8. The features are dominated by shock SiO-enriched gas. In such clouds, the ratio of the fractional abundance of SiO and H$^{13}$CO$^+$ molecules is $X$(SiO)$/X$(H$^{13}$CO$^+$) $\sim$ 100. The features are presumably made by supernova remnants. We found a prototypical example in GCM$-$0.02$-$0.07. It has two distinct structures. One is a ridge-like structure contacting with the Sgr A East shell; another is an expanding shell-like structure. There is a wide-velocity width ridge of SiO-enriched gas in GCM 0.11$-$0.11, which is adjacent to Vertical filaments. This suggests that the collision with the molecular cloud accelerates relativistic electrons, which illuminate the Vertical filaments–Polarized Plumes complex.