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Chandra and HST Imaging of the Quasars PKS B0106+013 and 3C 345: Inverse Compton X-Rays and Magnetized Jets
Marshall, H. L.; Kharb, P.; Lister, M. L. +1 more
We present results from deep (~70 ks) Chandra/ACIS observations and Hubble Space Telescope (HST) Advanced Camera for Surveys F475W observations of two highly optically polarized quasars belonging to the MOJAVE blazar sample, viz., PKS B0106+013 and 1641+399 (3C 345). These observations reveal X-ray and optical emissions from the jets in both sourc…
Herschel/HIFI observations of molecular emission in protoplanetary nebulae and young planetary nebulae
Waters, L. B. F. M.; Menten, K. M.; Olofsson, H. +16 more
Aims: We aim to study the physical conditions, particularly the excitation state, of the intermediate-temperature gas in protoplanetary nebulae and young planetary nebulae (PPNe, PNe). The information that the observations of the different components deliver is of particular importance for understanding the evolution of these objects.
Me…
Circulation of the Venus upper mesosphere/lower thermosphere: Doppler wind measurements from 2001-2009 inferior conjunction, sub-millimeter CO absorption line observations
Moriarty-Schieven, Gerald; Clancy, R. Todd; Sandor, Brad J.
Sub-millimeter 12CO (346 GHz) and 13CO (330 GHz) line absorptions, formed within the mesospheric to lower thermospheric altitude (70-120 km) region of the Venus atmosphere, have been mapped across the nightside disk of Venus during 2001-2009 inferior conjunctions, employing the James Clerk Maxwell Telescope (JCMT). Radiative …
Kinematics and helicity evolution of a loop-like eruptive prominence
Vial, J. -C.; Madjarska, M. S.; Schrijver, C. J. +4 more
Aims: We aim at investigating the morphology as well as kinematic and helicity evolution of a loop-like prominence during its eruption.
Methods: We used multi-instrument observations from AIA/SDO, EUVI/STEREO and LASCO/SoHO. The kinematic, morphological, geometrical, and helicity evolution of a loop-like eruptive prominence were studied …
Spectroscopic observations of propagating disturbances in a polar coronal hole: evidence of slow magneto-acoustic waves
Solanki, S. K.; Marsch, E.; Teriaca, L. +2 more
Aims: We focus on detecting and studying quasi-periodic propagating features that have been interpreted in terms of both slow magneto-acoustic waves and of high-speed upflows.
Methods: We analyzed long-duration spectroscopic observations of the on-disk part of the south polar coronal hole taken on 1997 February 25 by the SUMER spectromet…
An ancient metal-poor population in M32, and halo satellite accretion in M31, identified by RR Lyrae stars
Lauer, Tod R.; Yang, S. -C.; Sarajedini, Ata +2 more
We present time series photometry of two fields near M32 using archival observations from the Advanced Camera for Surveys Wide Field Channel on-board the Hubble Space Telescope. One field is centred about 2 arcmin from M32, while the other is located 15 arcmin to the south-east of M31. The imaging covers a time baseline sufficient for the identifi…
Observational evidence for composite grains in an AGB outflow. MgS in the extreme carbon star LL Pegasi
Waters, L. B. F. M.; Mutschke, H.; de Koter, A. +5 more
The broad 30 µm feature in carbon stars is commonly attributed to MgS dust particles. However, reproducing the 30 µm feature with homogeneous MgS grains would require much more sulfur relative to the solar abundance. Direct gas-phase condensation of MgS occurs at a low efficiency. Precipitation of MgS on SiC precursor grains provides a…
XMM-Newton Observation of PSR B2224+65 and Its Jet
Cheng, K. S.; Takata, J.; Hui, C. Y. +4 more
We have investigated the pulsar PSR B2224+65 and its X-ray jet with XMM-Newton. Apart from the long X-ray jet which is almost perpendicular to the direction of proper motion, a putative extended feature at the pulsar position, which is oriented in the opposite direction to the proper motion, is also suggested by this deep X-ray imaging. Non-detect…
XMM-Newton evidence of shocked ISM in SN 1006: indications of hadronic acceleration
Miceli, M.; Bocchino, F.; Decourchelle, A. +5 more
Context. Shock fronts in young supernova remnants are the best candidates for being sites of cosmic ray acceleration up to a few PeV, though conclusive experimental evidence is still lacking.
Aims: Hadron acceleration is expected to increase the shock compression ratio, providing higher postshock densities, but X-ray emission from shocked amb…
Elusive Ethylene Detected in Saturn's Northern Storm Region
Fletcher, L. N.; Irwin, P. G. J.; Achterberg, R. K. +9 more
The massive eruption at 40°N (planetographic latitude) on Saturn in 2010 December has produced significant and lasting effects in the northern hemisphere on temperature and species abundances. The northern storm region was observed on many occasions in 2011 by Cassini's Composite Infrared Spectrometer (CIRS). In 2011 May, temperatures in the strat…