bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photometric Investigations of Three Short-Period Binary Systems: GSC 0763−0572, RR Centauri, and ϵ Coronae Australis
Authors: Yang Yuan-Gui , Qian Sheng-Bang , Zhu Li-Ying , He Jia-Jia , Jin-Zhao Yuan 
Published: March 2014

Abstract
CCD photometric observations of the short-period eclipsing binary GSC 0763–0572 were carried out in the $B$ and $V$ bands at Yunnan Observatory in China. Three light minimum times were determined from the observations and the orbital period of this system was revised. Photometric solutions for three W UMa-type stars (i.e., GSC 0763–0572, RR Cen, and $\epsilon$ CrA) were deduced by the 2003 version of the Wilson–Devinney code with and without third lights. All three systems are found to be A-type eclipsing binaries with low mass ratios. Combining with the radial-velocity curves for RR Cen (King, Hilditch 1984, MNRAS, 209, 645) and $\epsilon$ CrA (Goecking, Duerbeck 1993, A&A, 278, 463), the absolute parameters for those two binaries were redetermined. Based on all minimum times of RR Cen, it is found that the orbital period shows a long-term increase superimposed on a cyclic variation. The secular change with a rate of $dP/dt = +1.21 \times 10^{-7} \,\mathrm{d} \,\mathrm{yr}^{-1}$ may suggest that RR Cen is undergoing mass transfer from the secondary component to the primary one with $dm/dt = +3.12 \times10^{-8} \,{{{M}_{\odot}}} \,\mathrm{yr}^{-1}$. The cyclic oscillation with a period of $65.1 \,(\pm 0.4) \,\mathrm{yr}$ and an amplitude of $0.0124 \,(\pm 0.0007) \,\mathrm{d}$ may be explained by the presence of a third body, which can be identified by the revised photometric solution. It is believed that if the orbital period increases for those systems is true, this kind of binary may evolve into a rapid-rotating single star.
The 2003/2004 Superoutburst of SDSS J013701.06−091234.9
Authors: Imada Akira , Kato Taichi , Kubota Kaori , Uemura Makoto , Ishioka Ryoko , Kiyota Seiichiro , Kinugasa Kenzo , Maehara Hiroyuki , Nakajima Kazuhiro , Monard L. A. G. Berto , Starkey Donn R. , Oksanen Arto , Nogami Daisaku 
Published: March 2014

Abstract
We report on time-resolved photometry of the superoutburst of an SU UMa-type dwarf nova, SDSS J013701.06$-$091234.9, in 2003 December–2004 January. The obtained light curves definitely show superhumps with a period of 0.056686(12)d, which is one of the shortest superhump periods among those of SU UMa-type dwarf novae ever observed. Considering quiescent photometric studies, we estimated the fractional superhump excess to be 0.024. Spectroscopic observations by Szkody et al. (2003, AJ, 126, 1499) provided evidence for TiO bands despite the short orbital period, implying that the system has a luminous secondary star. We have drawn a color-color diagram of SU UMa-type dwarf novae in quiescence using 2MASS archives, revealing that the location of this star in the color-color diagram deviates from the general trend. The distance to the system was roughly estimated to be $300 \pm 80 \,\mathrm{pc}$, using the empirical period–absolute magnitude relation and based on the proper motion.
Quasi-Periodic Oscillations of Microwave Emission in Solar Active Regions
Authors: Gelfreikh George B. , Nagovitsyn Yury A. , Nagovitsyna Elena Yu. 
Published: March 2014

Abstract
In this paper we discuss QPOs registered at microwaves using the Nobeyama Radioheliograph (NoRH). Our main conclusions concerning the QPO, found from NoRH observations, include: In addition to widely known 3-min oscillations and comparatively less investigated shorter fluctuations, we have registered over sunspots at microwave range also a diversity of more long-term periodic processes having typical periods of tens and hundreds of minutes. In some sunspots these periods are dominating. In a single active region, different plasma structures can simultaneously oscillate within a long-term range with different periods. Most of the different plasma structures of the solar atmosphere registered at the Nobeyama radio maps at a wavelength of 1.76 cm at all heliographic latitudes show the presence of the long-term QPO. In observations of the QPO at microwaves, we have dealt mostly with nonstationary processes. We have thus used wavelet analysis to estimate the quality of proper plasma resonators responsible for QPOs. In our interpretation, three types of plasma oscillators were proposed to be of importance: resonators that coincide with the emitting region; resonators that are outside, but close to the radio emitter; and resonators of the global solar nature. We conclude that NoRH has opened a new era in the study of different quasi-periodic oscillations and waves in the plasma structures of the solar atmosphere.
Self-Similar Solutions for ADAF with Toroidal Magnetic Fields
Authors: Akizuki Chizuru , Fukue Jun 
Published: March 2014

Abstract
We examined the effect of toroidal magnetic fields on a viscous gaseous disk around a central object under an advection-dominated stage. We found self-similar solutions for the radial infall velocity, rotation velocity, and sound speed, with an additional parameter, $\beta \; [=c_{\mathrm{A}}^2/(2 \,c_{\mathrm{s}}^2)$], where $c_{\mathrm{A}}$ is the Alfvén speed and $c_{\mathrm{s}}$ is the isothermal sound speed. Compared with the non-magnetic case, in general the disk becomes thick due to the magnetic pressure, and the radial infall velocity and rotation velocity become fast. In a particular case, where the magnetic field is dominant, on the other hand, the disk becomes to be magnetically supported, and the nature of the disk is significantly different from that of the weakly magnetized case.
Sequential Formation of Low-Mass Stars in the BRC 14 Region*
Authors: Ikuko Matsuyanagi , Itoh Yoichi , Sugitani Koji , Oasa Yumiko , Mukai Tadashi , Tamura Motohide 
Published: March 2014

Abstract
We carried out a deep near-infrared survey of a bright-rimmed molecular cloud, BRC 14 (IC 1848A). The $10\,\sigma$ limiting magnitude of the survey is 17.7 mag at the $K$-band. Seventy-four sources are classified as young stellar object (YSO) candidates based on a near-infrared color–color diagram. The faintest YSO candidates may have masses on the order of tenths of the solar mass, assuming an age of 1 Myr. We examined three values as indicators of star formation: fraction of the YSO candidates, extinctions of all sources, and near-infrared excesses of the YSO candidates. All indicators increase from outside of the rim to the center of the molecular cloud, which suggests that the formation of the low-mass stars in the BRC 14 region proceeds from outside to the center of the cloud.
Dynamical Effects of Cold Dark Matter Subhalos on a Galactic Disk
Authors: Hayashi Hirohito , Chiba Masashi 
Published: March 2014

Abstract
We have investigated the dynamical interaction between a galactic disk and numerous surrounding dark subhalos as expected for a galaxy-sized halo in the cold dark matter models. Our particular interest is to what extent accretion events of subhalos into a disk are allowed in light of the observed thinness of a disk. Several models of subhalos were considered in terms of their internal density distribution, mass function, and spatial and velocity distributions. Based on a series of $N$-body simulations, we find that disk thickening, quantified by the change of its scale height, $\Delta z_{\mathrm{d}}$, depends strongly on the individual mass of an interacting subhalo, $M_\mathrm{sub}$. This is described by the relation $\Delta z_{\mathrm{d}} / R_{\mathrm{d}} \simeq 8 \sum_{j=1}^N (M_{\mathrm{sub},j} / M_{\mathrm{d}})^2$, where $R_{\mathrm{d}}$ is the disk scale length, $M_{\mathrm{d}}$ is the disk mass, and $N$ is the total number of accretion events of subhalos inside a disk region ($\le 3 R_{\mathrm{d}}$). Using this relation, we find that an observed thin disk has never interacted with subhalos with a total mass of more than 15% of the disk mass. Also, a less-massive disk with a smaller circular velocity, $V_{\mathrm{c}}$ is more affected by subhalos than a disk with a larger $V_{\mathrm{c}}$, in agreement with observations. Further implications of our results for the origin of a thick disk component are also discussed.
Three-Dimensional Distribution of the ISM in the Milky Way Galaxy: II. The Molecular Gas Disk
Authors: Nakanishi Hiroyuki , Sofue Yoshiaki 
Published: March 2014

Abstract
We created a three-dimensional distribution map of molecular gas throughout the Milky Way galaxy using the latest ${{12\atop} \mathrm{CO}}$ ($J = 1 \hbox{--} 0$) survey data cube and the rotation curve based on the kinematic distance. The radial distribution of the molecular gas shows a central peak and a second peak around $0.5 \,R_0$ ($R_0$: the solar Galactocentric distance). The thickness of the molecular disk slightly increases from 48 pc to 160 pc with the Galactocentric distance within a radius range of 0–11 kpc. We were able to trace the Outer, the Perseus, the Sagittarius–Carina, the Scutum–Crux, and the Norma arms as logarithmic spiral arms with pitch angles of $11 {{}^{\circ }} \hbox{--} 15^\circ$. Considering that the pitch angles of the spiral arms are within this range, the Norma and the Outer arms seem to be identified as the same spiral arm. We could also trace a midplane displacement, whose amplitude is nearly constant inside a 10 kpc radius and increases beyond this radius. The ridges of the midplane displacement form the leading spiral arms.
Analysis of Adiabatic Dipolar Oscillations of Stars
Authors: Takata Masao 
Published: March 2014

Abstract
We theoretically discuss adiabatic dipolar oscillations of stars, fully taking into account the variation in the gravitational field. By suitably choosing the dependent variables, and using the first integral specific to dipolar oscillations, we derive the second-order system of ordinary differential equations, which is the same in form as that obtained by neglecting the Eulerian perturbation to the gravitational potential. The derived system suggests that the conventional expressions of the critical frequencies should be corrected. In addition, we present a rigorous scheme to classify the dipolar eigenmodes of linear adiabatic oscillations of spherically symmetric stars.
A CO J = 3–2 Survey of the Galactic Center
Authors: Oka Tomoharu , Makoto Nagai , Kazuhisa Kamegai , Kunihiko Tanaka , Nobuyuki Kuboi 
Published: March 2014

Abstract
We have surveyed the central molecular zone (CMZ) of our Galaxy in the CO J$=$3–2 line with the Atacama Submillimeter-wave Telescope Experiment (ASTE). Molecular gas in the Galactic center shows a high J$= 3-2/J = 1-0$ intensity ratio ($\sim 0.9$), while gas in the spiral arms of the Galactic disk shows a lower ratio ($\sim 0.5$). The high-velocity compact cloud CO $0.02-0.02$ and the hyperenergetic shell CO 1.27$+$0.01, as well as gas in the Sgr A region, exhibit high J$=$3–2$/J=$1–0 intensity ratios exceeding 1.5. We also found a number of small spots of high-ratio gas. Some of these high-ratio spots have large velocity widths and some seem to be associated with nonthermal threads or filaments. These could be spots of hot molecular gas shocked by unidentified supernovae, which may be abundant in the CMZ.
Photometric Observation and Numerical Simulation of Early Superhumps in BC Ursae Majoris during the 2003 Superoutburst
Authors: Maehara Hiroyuki , Hachisu Izumi , Nakajima Kazuhiro 
Published: March 2014

Abstract
We carried out time-resolved photometric observations of an SU UMa-type dwarf nova, BC UMa, during its superoutburst in 2003 February. The period of early superhumps is 0.06258(13)d and the amplitude is 0.04 mag. After the early superhump phase, common superhumps with an amplitude of 0.3 mag and a period of 0.064466(16) d developed. The change rate of the superhump periods ($\dot{P}_{\rm SH}/P_{\rm SH}$) ($P_{\rm SH}$: superhump period) was positive throughout the superoutburst. The superhump period excess ($\varepsilon \equiv P_{\rm SH}P_{\rm orb}^{-1}-1$) is 3% and we derived a mass ratio of 0.13. We have modeled early superhump light curves including irradiation effects of the accretion disk and secondary star. The observed early superhumps can be reproduced when two-armed spirals appear on the accretion disk. The long-term data taken from AAVSO, VSOLJ, and VSNET indicate that BC UMa shows normal outbursts and two types of superoutbursts (short-faint and long-bright). BC UMa is the first example to show such two types of superoutbursts. The supercycle of BC UMa is between 600 d and 1000d. This suggests that BC UMa is an intermediate type of dwarf novae between WZ Sge and SU UMa.
ASTE CO (3–2) Observations of the Barred Spiral Galaxy M 83: I. Correlation between CO (3–2)/CO (1–0) Ratios and Star Formation Efficiencies
Authors: Muraoka Kazuyuki , Kohno Kotaro , Tosaki Tomoka , Kuno Nario , Nakanishi Kouichiro , Sorai Kazuo , Okuda Takeshi , Sakamoto Seiichi , Endo Akira , Hatsukade Bunyo , Kamegai Kazuhisa , Tanaka Kunihiko , Cortes Juan , Ezawa Hajime , Yamaguchi Nobuyuki , Sakai Takeshi , Kawabe Ryohei 
Published: March 2014

Abstract
We present CO ($J = 3$–2) emission observations with the ASTE toward the $5' \times 5'$ (or 6.6 kpc $\times$ 6.6 kpc at the distance $D$ = 4.5 Mpc) region of the nearby barred spiral galaxy M 83. We successfully resolved the major structures, i.e., the nuclear starburst region, bar, and inner spiral arms at a resolution of $22''$ (480 pc), showing a good spatial coincidence between CO and 6 cm continuum emissions. We found a global luminosity, $L'_{\rm CO(3-2)}$, of $5.1 \times 10^8$ K km s$^{-1}$ pc$^2$ within the observed region. We also found $L'_{\rm CO(3-2)}$ in a disk region ($0.5 &lt; r &lt; 3.5$ kpc) of $4.2 \times 10^8$ K km s$^{-1}$ pc$^2$, indicating that ($J = 3$–2) emission in the disk region significantly contributes to the global $L'_{\rm CO(3-2)}$. From a comparison of CO ($J = 3$–2) data with CO ($J = 1$–0) intensities measured with the Nobeyama 45-m telescope, we found that the radial profile of the CO ($J = 3$–2)$/$CO ($J = 1$–0) integrated intensity ratio, $R_{3-2/1-0}$, is almost unity in the central region ($r &lt; 0.25$ kpc), whereas it drops to a constant value, 0.6–0.7, in the disk region. The radial profile of star formation efficiencies (SFEs), determined from 6 cm radio continuum and CO ($J = 1$–0) emission, shows the same trend as that of $R_{3-2/1-0}$. At the bar-end ($r \sim 2.4$ kpc), the amounts of molecular gas and the massive stars are enhanced when compared with other disk regions, whereas there is no excess of $R_{3-2/1-0}$ and SFE in that region. This means that a simple summation of the star-forming regions at the bar-end and the disk cannot reproduce the nuclear starburst of M 83, implying that the spatial variation of the dense gas fraction traced by $R_{3-2/1-0}$ governs the spatial variation of SFE in M 83.
Bispectrum and Nonlinear Biasing of Galaxies: Perturbation Analysis, Numerical Simulation, and SDSS Galaxy Clustering
Authors: Nishimichi Takahiro , Kayo Issha , Hikage Chiaki , Yahata Kazuhiro , Taruya Atsushi , Jing Yi Peng , Sheth Ravi K. , Suto Yasushi 
Published: March 2014

Abstract
We consider nonlinear biasing models of galaxies with particular attention to a correlation between the linear and quadratic biasing coefficients, $b_1$ and $b_2$. We first derive perturbative expressions for $b_1$ and $b_2$ in halo and peak biasing models. We then discuss our computations of the power spectra and bispectra of dark matter particles and halos using $N$-body simulation data and of volume-limited subsamples of Sloan Digital Sky Survey (SDSS) galaxies, and determine their $b_1$ and $b_2$. We find that the values of those coefficients at linear regimes ($k&lt;0.2$$h$ Mpc$^{-1}$) are fairly insensitive to the redshift-space distortion and the survey volume shape. The resulting normalized amplitudes of the bispectra, $Q$, for equilateral triangles are insensitive to the values of $b_1$, implying that $b_2$ indeed correlates with $b_1$. The present results explain the previous finding of Kayo et al. (2004, PASJ, 56, 415) for the hierarchical relation of three-point correlation functions of SDSS galaxies. While the relations between $b_1$ and $b_2$ are quantitatively different for specific biasing models, their approximately similar correlations indicate a fairly generic outcome of the biasing due to the gravity in primordial Gaussian density fields.
Probing the Disk–Jet Connection of the Radio Galaxy 3C 120 Observed with Suzaku
Authors: Kataoka Jun , Reeves James N. , Iwasawa Kazushi , Markowitz Alex G. , Mushotzky Richard F. , Arimoto Makoto , Takahashi Tadayuki , Tsubuku Yoshihiro , Ushio Masayoshi , Watanabe Shin , Gallo Luigi C. , Madejski Greg M. , Terashima Yuichi , Isobe Naoki , Tashiro Makoto S. , Kohmura Takayoshi 
Published: March 2014

Abstract
We report on deep (40ks $\times$ 4) observations of the bright broad line radio galaxy 3C 120 using Suzaku. The observations were spaced one week apart, and sampled a range of continuum fluxes. An excellent broadband spectrum was obtained over two decades of frequency (0.6 to 50 keV) within each 40ks exposure. We clearly resolved the iron K emission-line complex, finding that it consists of a narrow K$\alpha$ core ($\sigma \simeq$ 110 eV or an EW of 60 eV), a 6.9 keV line, and an underlying broad iron line. Our confirmation of the broad line contrasts with the XMM-Newton observation in 2003, where the broad line was not required. The most natural interpretation of the broad line is iron K line emission from a face-on accretion disk that is truncated at ~ 10 rg. Above 10 keV, a relatively weak Compton hump was detected (reflection fraction of R$\simeq$ 0.6), superposed on the primary X-ray continuum of $\Gamma \simeq$ 1.75. Thanks to the good photon statistics and low background of the Suzaku data, we clearly confirm the spectral evolution of 3C 120, whereby the variability amplitude decreases with increasing energy. More strikingly, we discovered that the variability is caused by a steep power-law component of $\Gamma \simeq$ 2.7, possibly related to non-thermal jet emission. We discuss our findings in the context of similarities and differences between radio-loud/quiet objects.
Multi-Slit Imaging Spectroscopy Technique: Catalog of Intracluster Planetary Nebulae in the Coma Cluster
Authors: Arnaboldi Magda , Gerhard Ortwin , Okamura Sadanori , Kashikawa Nobunari , Yasuda Naoki , Freeman Kenneth C. 
Published: March 2014

Abstract
With a new multi-slit imaging spectroscopy (MSIS) technique pioneered at the 8.2 m Subaru telescope and the Faint Object Camera and Spectrograph, we detect and measure the line-of-sight velocities of 40 intracluster planetary nebula candidates associated with the diffuse intracluster population of stars in the Coma cluster core, at nearly 100 Mpc distance. We describe the method for extracting the single two-dimensional spectra from the MSIS image, discuss the criteria for the identification of the emission line objects, and describe the procedure to compute their $\alpha, \delta$ (J2000) coordinates. We present the catalog of the intracluster planetary nebula candidates, their spatial location in the surveyed field, and their distribution in the velocity–magnitude plane. Finally, we comment on possible population effects and the use of these planetary nebulae to confirm the distance to the Coma cluster.
An SiO Maser Search off the Galactic Plane
Authors: Deguchi Shuji , Fujii Takahiro , Ita Yoshifusa , Imai Hiroshi , Izumiura Hideyuki , Kameya Osamu , Matsunaga Noriyuki , Miyazaki Atsushi , Mizutani Arihiro , Nakada Yoshikazu , Nakashima Jun-ichi , Winnberg Anders 
Published: March 2014

Abstract
We searched for the SiO $J=1$-0, $v= 1$ and 2 maser lines at $\sim 43$ GHz in 277 2 MASS/MSX/IRAS sources off the Galactic plane ($\vert b\vert\gtrsim 3^{\circ}$), which resulted in 119 (112 new) detections. Among the new detections, two are very faint objects with MSX 12$\mu$m flux densities below 2 Jy. These are likely to be O-rich AGB-stars associated with dwarf-galaxy tidal tails. The sample also includes medium bright MSX objects at moderately high galactic latitudes ($3^{\circ}&lt;\vert b\vert&lt;5^{\circ}$) and in the IRAS gap at higher latitudes. A signature of a warp of the inner Galactic disk is found for a disk subsample. This warp appears relatively strongly in the area of $0^{\circ}&lt;l&lt;45^{\circ}$ and $3^{\circ}&lt;\vert b\vert&lt;5^{\circ}$. We also found a group of stars that does not follow to the Galactic rotation. This feature appears in the Galactic disk at $l\sim 27^{\circ}$, and extends more than $15^{\circ}$ in the galactic latitude, like a stream of tidal debris from a dwarf galaxy.
HETE-2 Observations of the X-Ray Flash XRF 040916
Authors: Arimoto Makoto , Kawai Nobuyuki , Suzuki Motoko , Sato Rie , Pazmino Nicolas Vasquez , Shimokawabe Takashi , Ishimura Takuto , Kotoku Jun’ichi , Yoshida Atsumasa , Tamagawa Toru , Shirasaki Yuji , Matsuoka Masaru , Nakagawa Yujin , Ishikawa Nobuyuki , Kobayashi Akina , Sugita Satoshi , Takahashi Ichiro , Kuwahara Makoto , Yamauchi Makoto , Takagishi Kunio , Hatsukade Isamu , Atteia Jean-Luc , Pelangeon Alexandre , Vanderspek Roland , Graziani Carlo , Prigozhin Gregory , Villasenor Joel , Jernigan J. Garrett , Crew Geoffrey B. , Hurley Kevin , Sakamoto Takanori , Ricker George R. , Woosley Stanford E. , Butler Nat , Levine Al , Doty John P. , Donaghy Timothy Q. , Lamb Donald Q. , Fenimore Edward E. , Galassi Mark , Boer Michel , Dezalay Jean-Pascal , Olive Jean-François , Braga Joao , Manchanda Ravi , Pizzichini Graziella 
Published: March 2014

Abstract
A long X-ray flash was detected and localized by instruments aboard the High Energy Transient Explorer II (HETE-2) at 00:03:30 UT on 2004 September 16. The position was reported to the GRB Coordinates Network (GCN) approximately 2 hours after the burst. This burst consisted of two peaks separated by $\sim 200$ s, with durations of about 110 s and 60 s. We analyzed the energy spectra of the 1st and 2nd peaks observed with the Wide Field X-Ray Monitor (WXM) and the French Gamma Telescope (FREGATE). We discuss the origin of the 2nd peak in terms of the flux variabilities and timescales. We find that it is most likely to be part of prompt emission, and is explained by a long-acting engine model. This feature is similar to some bright X-ray flares detected in the early afterglow phase of bursts observed by the Swift satellite.
Japanese VLBI Network Observations of Radio-Loud Narrow-Line Seyfert 1 Galaxies
Authors: Doi Akihiro , Fujisawa Kenta , Inoue Makoto , Wajima Kiyoaki , Nagai Hiroshi , Harada Keiichiro , Suematsu Kousuke , Habe Asao , Honma Mareki , Kawaguchi Noriyuki , Kawai Eiji , Kobayashi Hideyuki , Koyama Yasuhiro , Kuboki Hiromitsu , Murata Yasuhiro , Omodaka Toshihiro , Sorai Kazuo , Sudou Hiroshi , Takaba Hiroshi , Takashima Kazuhiro , Takeda Koji , Tamura Sayaka , Wakamatsu Ken-ichi 
Published: March 2014

Abstract
We performed phase-reference very long baseline interferometry (VLBI) observations on five radio-loud narrow-line Seyfert 1 galaxies (NLS1s) at 8.4 GHz with the Japanese VLBI Network. Each of the five targets (RXS J08066$+$7248, RXS J16290$+$4007, RXS J16333$+$4718, RXS J16446$+$2619, and B3 1702$+$457) in milli-Jansky levels were detected and unresolved in milli-arcsecond resolutions, i.e., with brightness temperatures higher than $10^7$ K. The nonthermal processes of active galactic nucleus activity, rather than starbursts, are predominantly responsible for the radio emissions from these NLS1s. Out of the nine known radio-loud NLS1s, including those chosen for this study, we found that the four most radio-loud objects exclusively have inverted spectra. This suggests a possibility that these NLS1s are radio-loud due to Doppler beaming, which can apparently enhance both the radio power and the spectral frequency.