Dust Composition in the Low Density Medium Around Spica
نویسندگان
چکیده
منابع مشابه
Structure and chemical composition of the silicate dust around OH/IR stars
Using a radiative transfer code we have studied the dust shells of the two OH/IR stars IRAS 17004-4119 (OH344.93) and IRAS 17411-3154 (OH357). The ISO-SWS spectra of both sources exhibit deep amorphous silicate absorption bands at 9.8 and 17.5 μm together with crystalline silicate emission bands at 33.6, 40.5 and 43 μm. In both sources the 9.8 μm silicate band shows a shoulder at 11.2 μm. The a...
متن کاملDust around Type Ia supernovae
An explanation is given of the low value of Rλ ≡ Aλ/E(B − V ), the ratio of absolute to selective extinction deduced from Type Ia supernova observations. The idea involves scattering by dust clouds located in the circumstellar environment, or at the highest velocity shells of the supernova ejecta. The scattered light tends to reduce the effective Rλ in the optical, but has an opposite effect in...
متن کاملInvestigation of the dust environment around Europa
Space in the vicinity of atmosphereless bodies inthe Solar system is often populated by dustoriginating from the surface. Fragments of thesurface are ejected mostly due to hypervelocitymeteoroid impacts. It is also possible that materialfrom sub-surface layers may be vented throughcracks in the ice (as detected near Enceladus).The understanding of Europa's dust c...
متن کاملThe Dust and Gas around Pictoris
We have obtained Spitzer IRS 5.5Y35 m spectroscopy of the debris disk around Pictoris. In addition to the 10 m silicate emission feature originally observed from the ground, we also detect the crystalline silicate emission bands at 28 and 33.5 m. This is the first time that the silicate bands at wavelengths longer than 10 mhave ever been seen in the Pictoris disk. The observed dust emission is ...
متن کاملP-146: Fertility and Flow Cytometric Evaluations of Frozen-Thawed Rooster Semen in Cryopreservation Medium Containing Low Density Lipoprotein
Background: Frozen-thawed rooster semen is not reliable for use in artificial insemination in commercial stocks. Low density lipoprotein (LDL) has been assessed for effectiveness as a cryoprotectant in the extender to improve the quality of frozen-thawed rooster semen. Although LDL has been evaluated in a few studies in other species for semen cryopreservation, to date, no study has been conduc...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: International Astronomical Union Colloquium
سال: 1997
ISSN: 0252-9211
DOI: 10.1017/s0252921100071293