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The spectroscopic evolution of the symbiotic star AG Draconis. I. The O VI Raman, Balmer, and helium emission line variations during the outburst of 2006-2008

Wolf, M.; Bernabei, S.; Shore, S. N. +6 more

Context. AG Dra is one of a small group of low metallicity S-type symbiotic binaries with K-type giants that undergoes occasional short-term outbursts of unknown origin.
Aims: Our aim is to study the behavior of the white dwarf during an outburst using the optical Raman lines and other emission features in the red giant wind. The goal is to d…

The Electron Temperature of the Solar Transition Region as Derived from EIS and SUMER

Landi, E.; Doschek, G. A.; Muglach, K.

We use UV and extreme-UV emission lines observed in quiet regions on the solar disk with the Solar Ultraviolet Measurements of Emitted Radiation (SUMER) instrument and the Extreme Ultraviolet Imaging Spectrometer (EIS) to determine the electron temperature in solar transition region plasmas. Prominent emission lines of O IV and O VI are present in…

VLT/FLAMES-ARGUS observations of stellar wind-ISM cloud interactions in NGC 6357

Smith, L. J.; Gallagher, J. S., III; Westmoquette, M. S. +1 more

We present optical/near-IR integral field unit observations of a gas pillar in the Galactic HII region NGC 6357 containing the young open star cluster Pismis 24. These observations have allowed us to examine in detail the gas conditions of the strong wind-clump interactions taking place on its surface.

By accurately decomposing the Hα line pr…

The disk-bearing young star IM Lupi. X-ray properties and limits on accretion

Schmitt, J. H. M. M.; Güdel, M.; Günther, H. M. +3 more

Context. Classical T Tauri stars (CTTS) differ in their X-ray signatures from older pre-main sequence stars, e.g., weak-lined TTS (WTTS). CTTS exhibit a soft excess and deviations from the low-density coronal limit in the He-like triplets.
Aims: We test whether these features correlate with either accretion or the presence of a disk by observ…

Polarisation observations of VY Canis Majoris H₂O 5₃₂-4₄₁ 620.701 GHz maser emission with HIFI

Waters, L. B. F. M.; Menten, K. M.; Olofsson, H. +26 more

Context. Water vapour maser emission from evolved oxygen-rich stars remains poorly understood. Additional observations, including polarisation studies and simultaneous observation of different maser transitions may ultimately lead to greater insight.
Aims: We have aimed to elucidate the nature and structure of the VY CMa water vapour masers i…

Multi-spacecraft Observations of the 2008 January 2 CME in the Inner Heliosphere

Liu, Y.; Wu, S. T.; Feng, X. S. +4 more

We perform a detailed analysis of a coronal mass ejection (CME) on 2008 January 2. The combination of the Solar and Heliospheric Observatory and the twin STEREO spacecraft provides three-point observations of this CME. We track the CME in imaging observations and compare its morphology and kinematics viewed from different vantage points. The shape…

FGM Data Products in the CAA

Balogh, A.; Lucek, E. A.; Carr, C. M. +6 more

Set out in this paper is a description of the magnetic field and supporting data products that the FGM team have generated and submitted to the Cluster Active Archive. A significant amount of effort has been put into the calibration and validation of the magnetic field data products and details of the calibration techniques used to produce these d…

Witnessing the Formation of a Brightest Cluster Galaxy in a Nearby X-ray Cluster

Raychaudhury, Somak; Mulchaey, John S.; Ponman, Trevor J. +3 more

The central dominant galaxies in galaxy clusters constitute the most massive and luminous galaxies in the universe. Despite this, the formation of these brightest cluster galaxies (BCGs) and the impact of this on the surrounding cluster environment remain poorly understood. Here we present multiwavelength observations of the nearby poor X-ray clus…

A Catalog of Suzaku/WAM Hard X-Ray Solar Flares

Yamaoka, Kazutaka; Endo, Akira; Morigami, Kouichi +10 more

We developed a catalog of solar flares in the hard X-ray band observed with the Wide-band All-sky Monitor (WAM) onboard the Suzaku satellite between 2005 July and 2009 November. During this period, 105 solar flares (GOES class X: 13, M: 29, C: 47, B: 16) were detected with WAM, including 10% of GOES-class C events reported during the same period. …

Impact-induced N₂ production from ammonium sulfate: Implications for the origin and evolution of N₂ in Titan’s atmosphere

Fukuzaki, Sho; Sekine, Yasuhito; Genda, Hidenori +3 more

Chemical reactions and volatile supply through hypervelocity impacts may have played a key role for the origin and evolution of both planetary and satellite atmospheres. In this study, we evaluate the role of impact-induced N ₂ production from reduced nitrogen-bearing solids proposed to be contained in Titan's crust, ammonium sulfate ((…