Search Publications
Infrared Morphology of Regions of Ionized Hydrogen
Wiebe, D. S.; Kirsanova, M. S.; Topchieva, A. P. +1 more
A search for infrared ring nebulae associated with regions of ionized hydrogen has been carried out. The New GPS Very Large Array survey at 20 cm forms the basis of the search, together with observations obtained with the Spitzer Space Telescope at 8 and 24 µm and the Herschel Space Telescope at 70 µm. Objects having ring-like morpholo…
The development of magnetic field line wander by plasma turbulence
Howes, Gregory G.; Bourouaine, Sofiane
Plasma turbulence occurs ubiquitously in space and astrophysical plasmas, mediating the nonlinear transfer of energy from large-scale electromagnetic fields and plasma flows to small scales at which the energy may be ultimately converted to plasma heat. But plasma turbulence also generically leads to a tangling of the magnetic field that threads t…
An infrared photometric and spectroscopic study of post-AGB stars
Janardhan, P.; Pandey, R.; Anandarao, B. G. +1 more
We present here Spitzer mid-infrared (IR) spectra and modelling of the spectral energy distribution (SED) of a selection of post-asymptotic giant branch (PAGB) stars. The mid-IR spectra of the majority of these sources showed spectral features such as polycyclic aromatic hydrocarbons (PAHs) and silicates in emission. Our results from SED modelling…
The shocked gas of the BHR71 outflow observed by Herschel: indirect evidence for an atomic jet
Podio, L.; Codella, C.; Ceccarelli, C. +7 more
Context. In the BHR71 region, two low-mass protostars IRS1 and IRS2 drive two distinguishable outflows. They constitute an ideal laboratory to investigate both the effects of shock chemistry and the mechanisms that led to their formation.
Aims: We aim to define the global morphology of the warm gas component of the BHR71 outflow and at modell…
CMEs' Speed, Travel Time, and Temperature: A Thermodynamic Approach
Flandes, Alberto; Lara, Alejandro; Durand-Manterola, Hector J. +2 more
Due to their important role in space weather, coronal mass ejections or CMEs have been thoroughly studied in order to forecast their speed and transit time from the Sun to the Earth. We present a thermodynamic analytical model that describes the dynamics of CMEs. The thermodynamic approach has some advantages with respect to the hydrodynamic appro…
The Phoenix galaxy as seen by NuSTAR
Harrison, F. A.; Stern, D.; Zhang, W. W. +18 more
Aims: We study the long-term variability of the well-known Seyfert 2 galaxy Mrk 1210 (also known as UGC 4203, or the Phoenix galaxy).
Methods: The source was observed by many X-ray facilities in the last 20 yr. Here we present a NuSTAR observation and put the results in the context of previously published observations.
Results: NuST…
An Incipient Debris Disk in the Chamaeleon I Cloud
Hernández, J.; Ribas, Á.; McClure, M. K. +5 more
The point at which a protoplanetary disk becomes a debris disk is difficult to identify. To better understand this, here we study the ∼40 au separation binary T 54 in the Chamaeleon I cloud. We derive a K5 spectral type for T 54 A (which dominates the emission of the system) and an age of ∼2 Myr. However, the dust disk properties of T 54 are consi…
High-resolution X-Ray Spectroscopy of the Seyfert 1 Galaxy Mrk 1040. Revealing the Failed Nuclear Wind with Chandra
Behar, E.; Turner, T. J.; Kraemer, S. B. +6 more
High-resolution X-ray spectroscopy of the warm absorber in the nearby X-ray bright Seyfert 1 galaxy Mrk 1040 is presented. The observations were carried out in the 2013-2014 timeframe using the Chandra High Energy Transmission Grating with a total exposure of 200 ks. A multitude of absorption lines from Ne, Mg, and Si are detected from a wide vari…
Surface brightness correction for compact extended sources observed by the AKARI Far-Infrared Surveyor in the slow-scan mode
Shirahata, Mai; Yamamura, Issei; Takita, Satoshi +5 more
We present a general surface brightness correction method for compact extended sources imaged in the slow-scan pointed observation mode of the Far-Infrared Surveyor (FIS) aboard the AKARI infrared astronomical satellite. Our method recovers correct surface brightness distribution maps by rescaling archived raw FIS maps using the surface-brightness…
Chandra imaging of the kpc extended outflow in 1H 0419-577
Kaastra, J. S.; Costantini, E.; Mehdipour, M. +3 more
The Seyfert 1 galaxy 1H 0419-577 hosts a kpc extended outflow that is evident in the [O III] image and that is also detected as a warm absorber in the UV/X-ray spectrum. Here, we analyze a 30 ks Chandra-ACIS X-ray image, with the aim of resolving the diffuse extranuclear X-ray emission and of investigating its relationship with the galactic outflo…