Thermal Radio Stars and High-Resolution Radio Observations

1984 ◽  
pp. 287-288
Author(s):  
Alan E. Wright
Keyword(s):  
High Resolution ◽  
Radio Observations ◽  
Thermal Radio ◽  
Radio Stars

scholarly journals Thermal Radio Stars and High-Resolution Radio Observations

1984 ◽  
Vol 110 ◽  
pp. 287-288
Author(s):  
Alan E. Wright
Keyword(s):  
High Resolution ◽  
Radio Telescopes ◽  
Radio Observations ◽  
Thermal Radio ◽  
Under Construction ◽  
Radio Stars

The main purpose of this talk is to outline a few of the problems in our understanding of thermal radio stars that may be resolved by the large arrays. Several radio telescopes in operation (such as the VLA and MERLIN arrays) or under construction (such as the Australia Telescope) have both the required resolution and sensitivity.

scholarly journals High-resolution radio observations of the Seyfert galaxy NGC 1068

1983 ◽  
Vol 202 (3) ◽  
pp. 647-656 ◽  
Author(s):  
A. Pedlar ◽  
R. V. Booler ◽  
R. E. Spencer ◽  
O. J. Stewart
Keyword(s):  
High Resolution ◽  
Seyfert Galaxy ◽  
Radio Observations ◽  
Ngc 1068

scholarly journals Small Galactic Nebulae

1987 ◽  
Vol 115 ◽  
pp. 191-192
Author(s):  
Yervant Terzian ◽  
Kenneth C. Turner
Keyword(s):  
High Resolution ◽  
Planetary Nebula ◽  
Physical Parameters ◽  
H Ii Regions ◽  
Radio Observations ◽  
Cluster Emission ◽  
Active Star ◽  
Star Forming ◽  
Cometary Nebula ◽  
Significant Flux

We have performed high resolution VLA radio observations for several small H II regions, including the cluster emission nebulae S258, S255, S257, and S256. The region (PP56) between S255 and S257 at λ2 cm reveals significant flux structure close to OH, H2O and infrared emitting sources as shown in Figure 1. The flux densities and positions are indicated in Table 1. Observations of the cometary nebula PP59 (S269) also reveal similar characteristics as shown in Figure 2. These regions are considered to be active star-forming clouds. The cometary nebula PP40 was also observed and we note that its physical parameters are very similar to those of a typical planetary nebula.

scholarly journals Non-thermal radio emission in Wolf-Rayet stars: is binarity a pre-requisite?

1999 ◽  
Vol 193 ◽  
pp. 348-349
Author(s):  
Sean M. Dougherty
Keyword(s):  
Radio Emission ◽  
Spectral Index ◽  
Thermal Emission ◽  
Radio Observations ◽  
Thermal Radio ◽  
Thermal Radio Emission ◽  
Thermal Emitters

Radio observations of Wolf-Rayet stars currently available in the literature are examined to determine whether binarity is a common feature of WR systems with non-thermal emission. Among 24 stars with observed spectral index values, seven are definite non-thermal emitters, and six others possibly have composite thermal/non-thermal spectra. Stellar companions have been identified in 71% of the non-thermal emitters, strongly supporting a link between non-thermal emission and binarity.

scholarly journals Discovery of a New X-ray Transient in Scorpius GRO J1655-40 ≡ X-ray Nova Scorpii 1994

1996 ◽  
Vol 165 ◽  
pp. 363-367
Author(s):  
W.S. Paciesas ◽  
S.N. Zhang ◽  
B.C. Rubin ◽  
B.A. Harmon ◽  
C.A. Wilson ◽  
...  
Keyword(s):  
Black Hole ◽  
High Resolution ◽  
Power Law ◽  
Radio Observations ◽  
X Ray ◽  
Black Hole Candidate ◽  
Radio Jets ◽  
Transient Source ◽  
Galactic Source ◽  
Photon Index

A bright transient X-ray source, GRO J1655-40 (X-ray Nova Scorpii 1994) was discovered with BATSE (the Burst and Transient Source Experiment) in late July 1994. More recently, the source also became a strong radio emitter, its rise in the radio being approximately anti-correlated with a decline in the hard X-ray intensity. High-resolution radio observations subsequent to this symposium showed evidence for superluminally expanding jets. Since the hard X-ray emission extends to at least 200 keV and we find no evidence of pulsations, we tentatively classify the source as a black-hole candidate. However, its hard X-ray spectrum is unusually steep (power-law photon index α ≃ −3) relative to most other black-hole candidates. In this regard, it resembles GRS 1915+105, the first galactic source to show superluminal radio jets.

scholarly journals Are ELFs Little Monsters?

1989 ◽  
Vol 134 ◽  
pp. 379-381 ◽  
Author(s):  
R.P. Norris
Keyword(s):  
High Resolution ◽  
Starburst Galaxies ◽  
Radio Observations ◽  
Merging Galaxies ◽  
Compact Sources

High resolution radio observations of Seyferts, starbursts, and ELFs are presented which suggest that (i) starburst galaxies do not generally possess a Seyfert-like core, (ii) some ELFs do have a Seyfert core, but only those with a Seyfert-like spectrum, (iii) other ELFs are more likely to be powered by starburst activity. Double compact sources are present in several ELFs, suggesting that we might be seeing the nuclei of two merging galaxies, and that the ELFs are conceived by the coupling of two monsters.

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