Search Publications
VLBI Astrometry of the Semiregular Variable RX Bootis
Tafoya, Daniel; Kurayama, Tomoharu; Honma, Mareki +10 more
We present distance measurements of the semiregular variable RX Bootis (RX Boo) with its annual parallax. Using the unique dual-beam system of the VLBI Exploration of Radio Astrometry (VERA) telescope, we conducted astrometric observations of a water maser spot accompanying RX Boo, referred to the quasar J1419+2706 separated by 1.°69 from RX Boo. …
Discovery of the Most Isolated Globular Cluster in the Local Universe
Lee, Myung Gyoon; Jang, In Sung; Lim, Sungsoon +1 more
We report the discovery of two new globular clusters in the remote halos of M81 and M82 in the M81 Group based on Hubble Space Telescope archive images. They are brighter than typical globular clusters (MV = -9.34 mag for GC-1 and MV = -10.51 mag for GC-2), and much larger than known globular clusters with similar luminosity …
Formulation of a wind specification for Titan late polar summer exploration
Achterberg, Richard K.; Lorenz, Ralph D.; Tokano, Tetsuya +4 more
Titan's polar regions, and its hydrocarbon lakes in particular, are of interest for future exploration. The polar conditions have considerable seasonal variation and are distinct from the equatorial environment experienced by Huygens. Thus specific environmental models are required for these regions. This paper, informed by Cassini and groundbased…
Recurrent Radio Outbursts at the Center of the NGC 1407 Galaxy Group
Raychaudhury, Somak; Clarke, Tracy E.; Giacintucci, Simona +6 more
We present deep Giant Metrewave Radio Telescope (GMRT) radio observations at 240, 330, and 610 MHz of the complex radio source at the center of the NGC 1407 galaxy group. Previous GMRT observations at 240 MHz revealed faint, diffuse emission enclosing the central twin-jet radio galaxy. This has been interpreted as an indication of two possible rad…
The Free Energy of NOAA Solar Active Region AR 11029
Leka, K. D.; Wheatland, M. S.; Gilchrist, S. A.
The NOAA active region (AR) 11029 was a small but highly active sunspot region which produced 73 GOES soft X-ray flares during its transit of the disk in late October 2009. The flares appear to show a departure from the well-known power law frequency-size distribution. Specifically, too few GOES C-class and no M-class flares were observed by compa…
What are the physical mechanisms of eruptions and CMEs?
Aulanier, Guillaume; Schmieder, Brigitte
CMEs are due to physical phenomena that drive both, eruptions and flares in active regions. Eruptions/CMEs must be driven from initially force-free current-carrying magnetic field. Twisted flux ropes, sigmoids, current lanes and pattern in photospheric current maps show a clear evidence of currents parallel to the magnetic field. Eruptions occur s…
A Conditional Luminosity Function Model of the Cosmic Far-infrared Background Anisotropy Power Spectrum
Cooray, Asantha; De Bernardis, Francesco
The cosmic far-infrared background (CFIRB) is expected to be generated by faint, dusty star-forming galaxies during the peak epoch of galaxy formation. The anisotropy power spectrum of the CFIRB captures the spatial distribution of these galaxies in dark matter halos and the spatial distribution of dark matter halos in the large-scale structure. E…
The nuclear polycyclic aromatic hydrocarbon emission of merger system NGC 1614: rings within rings
Reunanen, Juha; Väisänen, Petri; Zijlstra, Albert A. +2 more
It is important to understand the interplay between nuclear star formation and nuclear activity when studying the evolution of gas-rich galaxy mergers. We present here new spatially resolved L-band integral field unit observations of the inner kpc of the luminous infrared galaxy NGC 1614. A broad ring of 3.3-µm polycyclic aromatic hydrocarbo…
Turbulent Characteristics in the Intensity Fluctuations of a Solar Quiescent Prominence Observed by the Hinode Solar Optical Telescope
Foullon, C.; Chapman, S. C.; Leonardis, E.
We focus on Hinode Solar Optical Telescope (SOT) calcium II H-line observations of a solar quiescent prominence (QP) that exhibits highly variable dynamics suggestive of turbulence. These images capture a sufficient range of scales spatially (~0.1-100 arcsec) and temporally (~16.8 s-4.5 hr) to allow the application of statistical methods used to q…
Tidal control of jet eruptions on Enceladus as observed by Cassini ISS between 2005 and 2007
Spitale, J. N.; Helfenstein, P.; Hurford, T. A.
Observations of Enceladus have revealed active jets of material erupting from cracks on its south polar surface. It has previously been proposed that diurnal tidal stress, driven by Enceladus' orbital eccentricity, may actively produce surface movement along these cracks daily and thus may regulate when eruptions occur. Our analysis of the stress …