Search Publications
[O I] disk emission in the Taurus star-forming region
Woitke, P.; Kamp, I.; Güdel, M. +8 more
Context. The structure of protoplanetary disks is thought to be linked to the temperature and chemistry of their dust and gas. Whether the disk is flat or flaring depends on the amount of radiation that it absorbs at a given radius and on the efficiency with which this is converted into thermal energy. The understanding of these heating and coolin…
Disentangling a group of lensed submm galaxies at z∼ 2.9
Ivison, R. J.; Richard, Johan; Smail, Ian +17 more
MS 0451.6-0305 is a rich galaxy cluster whose strong lensing is particularly prominent at submm wavelengths. We combine new Submillimetre Common-User Bolometer Array (SCUBA)-2 data with imaging from Herschel Spectral and Photometric Imaging Receiver (SPIRE) and PACS and Hubble Space Telescope in order to try to understand the nature of the sources…
Hard X-Ray Emission and 44Ti Line Features of the Tycho Supernova Remnant
Wang, Wei; Li, Zhuo
A deep hard X-ray survey of the International Gamma-Ray Astrophysics Laboratory (INTEGRAL) satellite has detected for the first time non-thermal emission up to 90 keV in the Tycho supernova (SN) remnant. Its 3-100 keV spectrum is fitted with a thermal bremsstrahlung of kT ~ 0.81 ± 0.45 keV plus a power-law model of Γ ~ 3.01 ± 0.16. Based on diffus…
TYC 3159-6-1: a runaway blue supergiant
Miroshnichenko, A. S.; Gvaramadze, V. V.; Zharikov, S. V. +2 more
We report the results of optical spectroscopy of a candidate evolved massive star in the Cygnus-X region, TYC 3159-6-1, revealed via detection of its curious circumstellar nebula in archival data of the Spitzer Space Telescope. We classify TYC 3159-6-1 as an O9.5-O9.7 Ib star and derive its fundamental parameters by using the stellar atmosphere co…
A Combined Study of Photospheric Magnetic and Current Helicities and Subsurface Kinetic Helicities of Solar Active Regions during 2006-2013
Komm, R.; Petrie, G. J. D.; Seligman, D.
We compare the average photospheric current helicity Hc , photospheric twist parameter α (a well-known proxy for the full relative magnetic helicity), and subsurface kinetic helicity Hk for 194 active regions observed between 2006-2013. We use 2440 Hinode photospheric vector magnetograms, and the corresponding subsurface flui…
The magnetic structure of Saturn's magnetosheath
Dougherty, M. K.; Jia, X.; Masters, A. +1 more
A planet's magnetosheath extends from downstream of its bow shock up to the magnetopause, where the solar wind flow is deflected around the magnetosphere and the solar wind-embedded magnetic field lines are draped. This makes the region an important site for plasma turbulence, instabilities, reconnection, and plasma depletion layers. A relatively …
Molecules in the transition disk orbiting T Chamaeleontis
Kastner, J. H.; Zuckerman, B.; Forveille, T. +4 more
Aims: We seek to establish the presence and properties of gas in the circumstellar disk orbiting
Methods: We used the Atacama Pathfinder Experiment (APEX) 12 m radiotelescope to search for submillimete…
Test of consistency between Planck and WMAP
Hazra, Dhiraj Kumar; Shafieloo, Arman
Within the context of the concordance model of cosmology we test the consistency of the angular power spectrum data from WMAP and Planck looking for possible systematics. The best fit concordance model to each observation is used as a mean function along with a Crossing function with an orthogonal basis to fit the data from the other observation s…
Dwarf Irregular Galaxy Leo A: Suprime-Cam Wide-field Stellar Photometry
Tamura, Naoyuki; Arimoto, Nobuo; Stonkutė, Rima +3 more
We have surveyed a complete extent of Leo A—an apparently isolated gas-rich low-mass dwarf irregular galaxy in the Local Group. The B, V, and I passband CCD images (typical seeing ~0.''8) were obtained with the Subaru Telescope equipped with the Suprime-Cam mosaic camera. The wide-field (20' × 24') photometry catalog of 38,856 objects (V ~ 16-26 m…
Time Evolution of the Altitude of an Observed Coronal Wave
Parenti, S.; Schmieder, B.; Artzner, G. +1 more
The nature of coronal wave fronts is intensely debated. They are observed in several wavelength bands and are frequently interpreted as magnetosonic waves propagating in the lower solar atmosphere. However, they can also be attributed to the line-of-sight projection of the edges of coronal mass ejections. Therefore, estimating the altitude of thes…