Results 11 to 20 of about 37,456 (169)
The Astrophysical Journal, 1993 The formation and destruction processes of HeH + in nebulae are discussed, and calculations of the abundances of HeH + are presented. It is shown that for effective temperatures of the ionizing source exceeding 50,000 K, the abundances are of the order of 10 12 cm −2 , largely independent of the nebular parameters.
Alexander Dalgarno +1 more
openaire +2 more sources
The plerion nebula in IC 443: the XMM-Newton view [PDF]
, 2001 \xmm ~observations of the X-ray feature 1SAX J0617.1+2221 in the IC443 supernova remnant are reported.We resolve the structure of the nebula into a compact core with a hard spectrum of photon index $\gamma= 1.63^{+0.11}_{-0.10}$ in the 2--10 keV energy ...
A. M. Bykov +27 more
core +2 more sources
Emission Nebulae as Radio Sources [PDF]
Australian Journal of Physics, 1956 Attempts have been made to detect 14 bright emission nebulae at a wavelength of 3?5 m using a pencil-beam radio telescope with a beamwidth of 50 min of arc. Of these nebulae, six were probably observed in emission, seven were undetectable, and one, NGC 6357, was observed in absorption; radio isophotes were obtained for NGC 2237 and NGC 3372.
A. G. Little, KV Sheridan, B. Y. Mills
openaire +2 more sources
Discovery of an old nova remnant in the Galactic globular cluster M 22 [PDF]
, 2019 A nova is a cataclysmic event on the surface of a white dwarf in a binary system that increases the overall brightness by several orders of magnitude. Although binary systems with a white dwarf are expected to be overabundant in globular clusters (GCs ...
Bacon, Roland +13 more
core +4 more sources
The Continuum Emission from Planetary Nebulae [PDF]
Symposium - International Astronomical Union, 1988 The study of nebular continuum emission is important for several reasons (Pottasch 1984, Planetary Nebulae, Dordrecht: Reidel). First of all, it can provide information about the temperature and the density of the nebula, when the object is large enough, or when the central star is weak enough, so that the nebular continuum is easily observed without ...
openaire +3 more sources
The Nature of the Stingray Nebula from Radio Observations
, 2018 We have analysed the full suite of Australia Telescope Compact Array data for the Stingray planetary nebula. Data were taken in the 4- to 23-GHz range of radio frequencies between 1991 and 2016.
Akhter, Shaila +7 more
core +1 more source
On the Nature of the Emission of the Crab Nebula [PDF]
Symposium - International Astronomical Union, 1958 The emission of the Crab Nebula is perhaps connected with the internal motions of the gas. As shown by the observations, the power of the emission sources differs by some hundred times in different points of the amorphous mass (“wisps” and other details).
openaire +2 more sources
, 2017 Context. NGC 40 is a planetary nebula with diffuse X-ray emission, suggesting an interaction of the high speed wind from WC8 central star (CS) with the nebula.
Krishna, S. +5 more
core +1 more source
Multiwavelength Studies of PSR J1420-6048, a Young Pulsar in the Kookaburra [PDF]
, 2001 We present X-ray, radio, and infrared observations of the 68 ms pulsar PSR J1420-6048 and its surrounding nebula, a possible counterpart of the gamma-ray source GeV J1417-6100/3EG J1420-6038.
Mallory S. E. Roberts +4 more
core +3 more sources
The Luminous Blue Variable RMC127 as seen with ALMA and ATCA [PDF]
, 2017 We present ALMA and ATCA observations of the luminous blue variable \rmc. The radio maps show for the first time the core of the nebula and evidence that the nebula is strongly asymmetric with a Z-pattern shape.
Agliozzo, C. +14 more
core +4 more sources