Search Publications
Rapid Transition of Uncombed Penumbrae to Faculae during Large Flares
Liu, Chang; Wang, Haimin; Deng, Na
In the past two decades, the complex nature of sunspots has been disclosed with high-resolution observations. One of the most important findings is the "uncombed" penumbral structure, where a more horizontal magnetic component carrying most of Evershed flows is embedded in a more vertical magnetic background. The penumbral bright grains are locati…
Morpho-kinematic Analysis of the Point-symmetric, Bipolar Planetary Nebulae Hb 5 and K 3-17, A Pathway to Poly-polarity
López, J. A.; Steffen, W.; García-Díaz, Ma. T. +2 more
The kinematics of the bipolar planetary nebulae Hb 5 and K 3-17 are investigated in detail by means of a comprehensive set of spatially resolved high spectral resolution, long-slit spectra. Both objects share particularly interesting characteristics, such as a complex filamentary, rosette-type nucleus, axial point-symmetry, and very fast bipolar o…
X-Ray Spectral Variability in NGC 3783
Fabian, A. C.; Miller, J. M.; Reynolds, C. S. +6 more
NGC 3783 was observed for approximately 210 ks by Suzaku and in this time showed significant spectral and flux variability at both short (20 ks) and long (100 ks) timescales. The full observation is found to consist of approximately six "spectral periods" where the behavior of the soft (0.3-1.0 keV) and hard (2-10 keV) bands are somewhat distinct.…
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 …
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…
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…
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…
Discovery of "Warm Dust" Galaxies in Clusters at z ~ 0.3: Evidence for Stripping of Cool Dust in the Dense Environment?
Smail, I.; Altieri, B.; Valtchanov, I. +15 more
Using far-infrared imaging from the "Herschel Lensing Survey," we derive dust properties of spectroscopically confirmed cluster member galaxies within two massive systems at z ~ 0.3: the merging Bullet Cluster and the more relaxed MS2137.3-2353. Most star-forming cluster sources (~90%) have characteristic dust temperatures similar to local field g…
Helioseismology of a Realistic Magnetoconvective Sunspot Simulation
Birch, A. C.; Braun, D. C.; Rempel, M. +1 more
We compare helioseismic travel-time shifts measured from a realistic magnetoconvective sunspot simulation using both helioseismic holography and time-distance helioseismology, and measured from real sunspots observed with the Helioseismic and Magnetic Imager instrument on board the Solar Dynamics Observatory and the Michelson Doppler Imager instru…
Evolution of the Symbiotic Nova PU Vul—Outbursting White Dwarf, Nebulae, and Pulsating Red Giant Companion
Kato, Mariko; Hachisu, Izumi; Mikołajewska, Joanna
We present a composite light-curve model of the symbiotic nova PU Vul (Nova Vulpeculae 1979) that shows a long-lasting flat optical peak followed by a slow decline. Our model light curve consists of three components of emission, i.e., an outbursting white dwarf (WD), its M-giant companion, and the nebulae. The WD component dominates in the flat pe…