Evolved mass-losing stars such as Mira enrich the interstellar medium (ISM) significantly by their dust-rich molecular wind. When these stars move fast enough relative to the ISM, the interaction between the wind and ISM generates the structure known as the astropause (a stellar analog of the heliopause), which is a cometary stellar wind cavity bounded by the contact discontinuity surface betwe...

We present an analysis of Chandra observations of the galaxy clusters A2670 and A2107. Their cD galaxies have large peculiar velocities (> 200 km s) and thus the clusters appear to be undergoing mergers. In A2670, we find a comet-like structure around one of the brightest galaxies. At the leading edge of the structure, there is a cold front. The mass of the X-ray gas in the comet-like structure...

We investigate the question of whether ambipolar diffusion (ion-neutral drift) determines the smallest length and mass scale on which structure forms in a turbulent molecular cloud. We simulate magnetized turbulence in a mostly neutral, uniformly driven, turbulent medium, using a three-dimensional, two-fluid, magnetohydrodynamics (MHD) code modified from Zeus-MP. We find that substantial struct...

We study the mixing of chemical species in the interstellar medium (ISM). Recent observations suggest that the distribution of species such as deuterium in the ISM may be far from homogeneous. This raises the question of how long it takes for inhomogeneities to be erased in the ISM, and how this depends on the length scale of the inhomogeneities. We added a tracer field to the three-dimensional...

We present deep narrowband near-IR images and moderate resolution spectra of the young planetary nebula Hubble 12. These data are the first to show clearly the complex structure for this important planetary nebula. Images were obtained at λ = 2.12, 2.16, and 2.26 μm. The λ = 2.12 μm image reveals the bipolar nature of the nebula, as well as complex structure near the central star in the equator...

We present deep narrowband near-IR images and moderate resolution spectra of the young planetary nebula Hubble 12. These data are the first to show clearly the complex structure for this important planetary nebula. Images were obtained at λ = 2.12, 2.16, and 2.26 μm. The λ = 2.12 μm image reveals the bipolar nature of the nebula, as well as complex structure near the central star in the equator...

abstract purpose-the purpose of this paper is to review a sample of the literature relating to interpretive structural modelling (ism) and its deployment for modelling purposes in the area of supply chain management (scm). design/methodology/approach- the literature is examined from the three perspectives. first, concept of ism and examines ism as modelling technique. second, use of ism by the ...

We report on preliminary results from the recent multi-epoch neutral hydrogen absorption measurements toward three pulsars, B0823+26, B1133+16 and B2016+28, using the Arecibo telescope. We do not find significant variations in optical depth profiles over periods of 0.3 and 9–10 yr, or on spatial scales of 10–20 and 70–85 AU. The large number of non detections of the tiny scale atomic structure ...