wpo - bright type II supernovae

SN2004dj in NGC 2403 [Cam] + SN2004et in NGC 6946 [Cyg]

 
S.Moretti reports the discovery of m12.8 SN in NGC 6946 on 2004 Sept 27 via 0.4m telescope + CCD at Ravenna Italy at position 20h 35m 25.33s; Dec +60o 07' 17.7".  Spectra [Sept 28] via 1.82m Asiago telescope slows featureless spectrum with weak H-alpha in emission.

AAVSO Newsflash Special Notice (August 2, 2004) 0727+65 SN2004DJ
A bright supernova has been discovered by K. Itagaki, Teppo-cho, Yamagata, Japan in NGC 2403 (CBET#74). The supernova is near the NE edge of NGC 2403 and well placed for visual and CCD observations. The discovery was made on July 31.76 at roughly V magnitude of 11.2 and confirmed on Aug. 1.45 at V=11.3.
Hazel McGee (MGH) reports the supernova at around v=12.0 on Aug 02.97 under very poor observing conditions. AAVSO e and er-scale charts here.
position [E2000] R.A. 7h 37m 17s.02, Decl. = +65o 35' 57".8

  main SN spectra page  Ron Arbour's image

2004 Oct 6:  SN2004et recorded with regular camera lens eg 135mm f/2.8 lens + HX5 CCD piggybacked in driven scope.  Open star cluster NGC 6939 Np NGC 6946.    Inset is a part field low-res OG prism spectrogram via the same lens which shows the SN blended with an adjacent field star so no useful data recorded except for the defocus IR signature of Carbon star V778 Cyg Sf the SN.




2004 Aug 6/7: Bright SN at ~mag 11 in NGC 2403 discovered a week ago but thunderstorms and haze prevented WPO observation until tonight with the galaxy below Polaris and some ~27o above the northern meridian towards London's bright skyline.  This is my first type II SN which has bright emission lines clearly recorded in 120s exposures.   Supernova recorded in 90s via piggybacked 135mm f/2.8 lens + HX5 CCD.

From the explosion the spectrum shows a broad Ha emission line with blue-shifted absorption component adjacent [eg P Cyg profile].  With the parent galaxy's modest recessional radial velocity of 260km/s [eg <0.1% velocity of light] no galaxy red-shift detectable at this low spectral resolution.




 images & text [c] Maurice Gavin - 2004  566 041006