Note: this is an
archived version which has been superseded. The current SNR
catalogue is at
http://www.mrao.cam.ac.uk/surveys/snrs/
G89.0+4.7
HB21
- Right Ascension: 20 43 30
- Declination: +50 25
- Size (arcmin): 120×90
- Type: S
- Flux density at 1 GHz (Jy): 220
- Spectral Index: 0.40
- Radio: Distorted shell (4C50.52, an extragalactic double, is within the boundary of the remnant).
- Optical: Filaments possibly associated.
- X-ray: Detected from incomplete mapping.
References:
- Hirabayashi & Takahashi 1972, PASJ, 24, 231. 30-m dish at 4.2 GHz (11': S=160±40).
- Willis 1973, A&A, 26, 237. NRAO 300-ft at 2.7 GHz (5': S=148±16), plus optical filaments.
- Hill 1974, MNRAS, 169, 59. HMT at 1.4 GHz (3'×3'.9).
- Haslam et al. 1975, A&A, 39, 453. Effelsberg 100-m at 2.7 GHz (4'.4)
ADS
- Reich et al. 1983, in IAU101, p377. Effelsberg 100-m at 4.75 GHz (2'.5).
- Leahy 1987, MNRAS, 228, 907. IPC observations.
ADS
- Fukui & Tatematsu 1988, in SNRISM, p261. CO observations of the vicinity (2'.7).
- Tatematsu et al. 1990, A&A, 237, 189. DRAO at 408 MHz (3'.5×4'.5) and 1.4 GHz (1'.0×1'.3), including HI,
plus CO observations of adjacent molecular cloud.
ADS
Last updated: 19th May 1992
Dave Green/MRAO, Cambridge, UK/D.A.Green@mrao.cam.ac.uk