Related papers: Spectral Analysis of the Chandra Comet Survey
We present new Chandra and HST data for four gamma-ray blazars selected on the basis of radio morphology with the aim of revealing X-ray and optical emission from their jets at large scales. All the sources have been detected. Spectral…
Aims. The interaction of two isotropic stellar winds is studied in order to calculate the free-free emission from the wind collision region. The effects of the binary separation and the wind momentum ratio on the emission from the wind-wind…
The study of solar wind charge exchange (SWCX) emission is vital to both the X-ray astrophysics and heliophysics communities. SWCX emission contaminates all astrophysical observations in X-rays regardless of the direction. Ignoring this…
The past decade has seen a surge of interest in astrophysical charge exchange (CX). The impetus was the discovery of X-ray emission from comets in 1996, soon followed by the observation of CX emission in planetary atmospheres and throughout…
We surveyed 23 comets using the Infrared Array Camera on the Spitzer Space Telescope in wide filters centered at 3.6 and 4.5 microns. Emission in the 3.6 micron filter arises from sunlight scattered by dust grains; these images generally…
Context: The ionosphere of a comet is known to deflect the solar wind through mass loading, but the interaction is dependent on cometary activity. We investigate the details of this process at comet 67P using the Rosetta Ion Composition…
We present an analysis of simultaneous X-Ray and UV observations ofcomet C/2007 N3 (Lulin) taken on three days between January 2009 and March 2009 using the Swift observatory. For our X-ray observations, we used basic transforms to account…
We present new X-ray and radio observations of the WR star EZ CMa (HD 50896) obtained with XMM-Newton and the VLA. This WN4 star shows optical/UV variability at a period of 3.76 d whose cause is unknown. VLA flux measurements at five…
Atmospheric escape from close-in exoplanets is thought to be crucial in shaping observed planetary populations. Recently, significant progress has been made in observing this process in action through excess absorption in transit spectra…
2D axis-symmetric hydrodynamical simulations are presented which explore the interaction of stellar and disk winds with surrounding infalling cloud material. The star, and its accompanying disk, blow winds inside a cavity cleared out by an…
In this paper, we estimate the X-ray emission from close-in exoplanets. We show that the Solar/Stellar Wind Charge Exchange Mechanism (SWCX) which produces soft X-ray emission is very effective for hot Jupiters. In this mechanism, X-ray…
Charge exchange is an atomic process that primarily occurs at interfaces between the neutral and ionized gas. The study of the process has been carried out on three levels: the theoretical calculation of the cross sections, the laboratory…
The low resolution X-ray spectra around $\eta$ Car covering Tr 16 and part of Tr 14 have been extracted from a Chandra CCD ACIS image. Various analysis techniques have been applied to the spectra based on their count rates. The spectra with…
The supersonic stellar and disk winds possessed by massive young stellar objects will produce shocks when they collide against the interior of a pre-existing bipolar cavity (resulting from an earlier phase of jet activity). The shock heated…
We discuss the detection and evolution of a complex series of transient and quasi-static solar wind structures in the days following the well-known comet 2P / Encke tail disconnection event in April 2007. The evolution of transient solar…
We present sensitive 5.5 to 7.6 micron spectra of comet C/2003 K4 (LINEAR) obtained on 16 July 2004 (r_{h} = 1.760 AU, Delta_{Spitzer} = 1.409 AU, phase angle 35.4 degrees) with the Spitzer Space Telescope. The nu_{2} vibrational band of…
This analysis offers evidence of characteristic scale sizes in solar wind charge state data measured in-situ for thirteen quiet-sun Carrington rotations in 2008. Using a previously established novel methodology, we analyze the wavelet power…
We analyze new high-resolution Chandra X-ray images of the Wolf-Rayet binary system WR147. This system contains a WN8 star with an early-type companion located 0.6'' to its north, and is the only known early-type binary with a separation on…
We report on a Chandra line spectrum observation of the O supergiant, Zeta Orionis (O9.7 Ib). A 73.4 ks HETGS observation shows a wide range of ionization stages and line strengths over the wavelength range of 5 to 26 A. The observed…
Marked correlations are reported between the ionization of the X-ray line spectra of normal OB stars, as observed by the Chandra X-Ray Observatory, and their optical spectral types. These correlations include the progressive weakening of…