Search Publications
Spectroscopic observations and modelling of impulsive Alfvén waves along a polar coronal jet
Srivastava, A. K.; Murawski, K.; Dwivedi, B. N. +2 more
Context. The magnetic reconnection in the solar corona results in impulsively generated Alfvén waves, which drive a polar jet.
Aims: Using the Hinode/EIS 2'' spectroscopic observations, we study the intensity, velocity, and full width at half maximum (FWHM) variations of the strongest Fe XII 195.12 Å line along the jet to find the signature o…
ALMA Observations of the Largest Proto-Planetary Disk in the Orion Nebula, 114-426: A CO Silhouette
Di Francesco, James; Johnstone, Doug; Matthews, Brenda +7 more
We present ALMA observations of the largest protoplanetary disk in the Orion Nebula, 114-426. Detectable 345 GHz (856 µm) dust continuum is produced only in the 350 AU central region of the ∼1000 AU diameter silhouette seen against the bright {{H}}α background in Hubble Space Telescope images. Assuming optically thin dust emission at 345 GHz…
A Stacked Search for Intermediate-mass Black Holes in 337 Extragalactic Star Clusters
Miller-Jones, J. C. A.; Wrobel, J. M.; Nyland, K. E.
Forbes et al. recently used the Hubble Space Telescope to localize hundreds of candidate star clusters in NGC 1023, an early-type galaxy at a distance of 11.1 Mpc. Old stars dominate the light of 92% of the clusters and intermediate-age stars dominate the light of the remaining 8%. Theory predicts that clusters with such ages can host intermediate…
Motion of reconnection region in the Earth's magnetotail
Nakamura, Rumi; Semenov, Vladimir S.; Nakamura, Takuma K. M. +1 more
We obtain the X-line velocity in the Earth's magnetotail for 24 reconnection events observed by the Cluster spacecraft between 2001 and 2005. The data set consists of 10 single X-lines and 14 X-lines from the time intervals of multiple reconnection. Except for two X-lines from multiple reconnection, all the X-lines move tailward (radial outward) a…
Solar Dynamics, Rotation, Convection and Overshoot
Thompson, M. J.; Schou, J.; Roth, M. +3 more
We discuss recent observational, theoretical and modeling progress made in understanding the Sun's internal dynamics, including its rotation, meridional flow, convection and overshoot. Over the past few decades, substantial theoretical and observational effort has gone into appreciating these aspects of solar dynamics. A review of these observatio…
SHARDS: A Global View of the Star Formation Activity at z ~ 0.84 and z ~ 1.23
Barro, Guillermo; Pérez-González, Pablo G.; Koekemoer, Anton M. +22 more
In this paper, we present a comprehensive analysis of star-forming galaxies (SFGs) at intermediate redshifts (z ∼ 1). We combine the ultra-deep optical spectro-photometric data from the Survey for High-z Absorption Red and Dead Sources (SHARDS) with deep UV-to-FIR observations in the GOODS-N field. Exploiting two of the 25 SHARDS medium-band filte…
Discovery of Resolved Debris Disk around HD 131835
Chen, Christine H.; Fitzgerald, Michael P.; Graham, James R. +3 more
We report the discovery of the resolved disk around HD 131835 and present the analysis and modeling of its thermal emission. HD 131835 is a ∼15 Myr A2 star in the Scorpius-Centaurus OB association at a distance of 122.7-12.8+16.2 pc . The extended disk has been detected to ∼ 1\buildrel{\prime\prime}\over{.} 5 (200 AU) at 11.7…
Optical-near-IR analysis of globular clusters in the IKN dwarf spheroidal: a complex star formation history
Tudorica, A.; Georgiev, I. Y.; Chies-Santos, A. L.
Context. Age, metallicity, and spatial distribution of globular clusters (GCs) provide a powerful tool for reconstructing major star-formation episodes in galaxies. IKN is a faint dwarf spheroidal (dSph) in the M 81 group of galaxies. It contains five old GCs, which makes it the galaxy with the highest known specific frequency (SN = 126…
FTIR-based measurements of self-broadening and self-shift coefficients as well as line strength in the first overtone band of HCl at 1.76 µM
Li, Gang; Serdyukov, Anton; Gisi, Michael +2 more
FTIR spectra of the 2-0 band of HCl have been measured in the 5300-5900 cm-1 spectral region at 15 different pressures (0.05-2.5 bar) and at a spectral resolution of 0.07 cm-1. For the first time, reliable and consistent self-induced broadening and shift coefficients for the complete HCl 2-0 band have been reported. Line inte…
High-energy Properties of the Enigmatic Be Star γ Cassiopeiae
Hamaguchi, K.; Shrader, C. R.; Oskinova, L. M. +3 more
We present the results of a broadband X-ray study of the enigmatic Be star Gamma Cassiopeiae (herein γ Cas) based on observations made with both the Suzaku and INTEGRAL observatories. γ Cas has long been recognized as the prototypical example of a small subclass of Be stars with moderately strong X-ray emission dominated by a hot thermal component…