Search Publications
Flow pattern of accelerated cometary ions inside and outside the diamagnetic cavity of comet 67P/Churyumov-Gerasimenko
Behar, E.; Nilsson, H.; Goetz, C. +3 more
Analyzing data from the Ion Composition Analyzer on board the Rosetta spacecraft, we studied a flow pattern of accelerated cometary ions (40-80 eV) inside and outside the diamagnetic cavity of comet 67P/Churyumov-Gerasimenko (67P). We found that the accelerated ions are intermittently observed and are ten times more frequently observed outside the…
Twin CME Launched by a Blowout Jet Originated from the Eruption of a Quiet-Sun Mini-filament
Srivastava, A. K.; Dwivedi, B. N.; Rao, Y. K. +1 more
We study a quiet-Sun blowout jet which was observed on 2014 May 16 by the instruments on board the Solar Dynamics Observatory (SDO). We find the twin CME as jet-like and bubble-like CMEs simultaneously as observed by LASCO C2 on board the Solar and Heliospheric Observatory (SoHO), and the Solar Terrestrial Relation Observatory (STEREO_A and STEREO…
A SINFONI view of the nuclear activity and circumnuclear star formation in NGC 4303 - II. Spatially resolved stellar populations
Colina, L.; Burtscher, L.; Pastoriza, M. G. +11 more
We present a spatially resolved stellar population study of the inner ∼200 pc radius of NGC 4303 based on near-infrared integral field spectroscopy with SINFONI/VLT at a spatial resolution of 40-80 pc and using the STARLIGHT code. We found that the distribution of the stellar populations presents a spatial variation, suggesting an age stratificati…
Nonequilibrium Ionization Effects on Solar EUV and X-Ray Imaging Observations
Moon, Yong-Jae; Reeves, Katharine K.; Raymond, John C. +3 more
During transient events such as major solar eruptions, the plasma can be far from the equilibrium ionization state because of rapid heating or cooling. Nonequilibrium ionization (NEI) is important in rapidly evolving systems where the thermodynamical timescale is shorter than the ionization or recombination timescales. We investigate the effects o…
Luminosity Ratio between [O IV] 25.89 µm Line and Nuclear Continuum 12 µm as a Diagnostic for “Buried” AGNs
Imanishi, Masatoshi; Tanimoto, Atsushi; Ueda, Yoshihiro +3 more
We propose new diagnostics that utilize the [O IV] 25.89 µm and nuclear (subarcsecond scale) 12 µm luminosity ratios for identifying whether an active galactic nucleus (AGN) is deeply “buried” in their surrounding materials. Utilizing a sample of 16 absorbed AGNs at redshifts lower than 0.03 in the Swift/BAT catalog observed with Suzak…
Analysis of HST WFPC2 Observations of Centaur 29P/Schwassmann-Wachmann 1 while in Outburst to Place Constraints on the Nucleus’ Rotation State
Schambeau, Charles A.; Fernández, Yanga R.; Samarasinha, Nalin H. +2 more
We present analysis of Hubble Space Telescope observations of Centaur 29P/Schwassmann-Wachmann 1 (SW1) while in outburst to characterize the outburst coma and place constraints on the nucleus’ spin state. The observations consist of Wide Field and Planetary Camera 2 (WFPC2) images from Cycle 5, GO-5829 acquired on UT 1996 March 11.3 and 12.1, whic…
IRAM and Gaia views of multi-episodic star formation in IC 1396A. The origin and dynamics of the Class 0 protostar at the edge of an HII region
Fang, Min; Sicilia-Aguilar, Aurora; Roccatagliata, Veronica +3 more
Context. IC 1396A is a cometary globule that contains the Class 0 source IC 1396A-PACS-1, which was discovered with Herschel.
Aims: We use IRAM 30m telescope and Gaia DR2 data to explore the star formation history of IC 1396A and investigate the possibilities of triggered star formation.
Methods: IRAM and Herschel continuum data were use…
A Pluto-Charon Sonata: Dynamical Limits on the Masses of the Small Satellites
Kenyon, Scott J.; Bromley, Benjamin C.
During 2005-2012, images from Hubble Space Telescope (HST) revealed four moons orbiting Pluto-Charon. Although their orbits and geometric shapes are well-known, the 2σ uncertainties in the masses of the two largest satellites—Nix and Hydra—are comparable to their HST masses. Remarkably, gravitational n-body computer calculations of the long-term s…
HST F160W Imaging of Very Massive Galaxies at 1.5 < z < 3.0: Diversity of Structures and the Effect of Close Pairs on Number Density Estimates
Franx, Marijn; Muzzin, Adam; Labbé, Ivo +10 more
We present a targeted follow-up Hubble Space Telescope WFC3 F160W imaging study of very massive galaxies ({log}({M}star}/{M}⊙ )> 11.25) selected from a combination of ground-based near-infrared galaxy surveys (UltraVISTA, NEWFIRM Medium Band Survey-II , UKIRT Infrared Deep Sky Survey (UKIDSS) Ultra-Deep Survey (UDS) at 1.5…
Unity and Diversity of Yellow Hypergiants Family
Klochkova, V. G.
We present the results of long-term spectral monitoring of yellow hypergiants (YHGs) of northern hemisphere with a R ≥ 60 000 resolution. The spectra of these F–G stars of extreme luminosity, compactly located at the top of the Hertzsprung–Russell diagram revealed a variety of spectral features: various types of Hα profile, the presence (or absenc…