Wolf-Rayet stars


The Wolf-Rayet stars are massive stars (more than 25 solar masses), in a advanced stage of evolution and ejecting at high speed a hot gas (winds of 2000 km/s typically). They have exceptional hot surface temperature, about 100.000 K. The spectrum presents strong emission widened lines. Wolf-Rayet stars have lost their atmospheres and have exposed their heavy cores. One finds there the signature of ions of helium, carbon, nitrogen and oxygen in the spectra.

There are 2 class Wolf-Rayet star: type WN where dominates the ions of helium and nitrogen and type WC where dominates the ions of carbon, oxygen and helium.

The Wolf-Rayet stars are very rare. One counts some hardly more than 150 in our galaxy. One will find below a list of bright Wolf-Rayet accessible since the northern hemisphere. The co-ordinates are into 2000.0 equinox.

 WR      HD          R.A.          Dec.       Type    V

  1     4004      0 43 28.4     +64 45 35     WN5   10.12
  2     6327      1 05 23.0     +60 25 19     WN2   11.43
  3     9974      1 38 55.7     +58 09 23     WN3   10.62
  4    16523      2 41 11.6     +56 43 50     WC5    9.98
  5    17638      2 52 11.7     +56 56 07     WC6   10.51
  6    50896      6 54 13.0     -23 55 42     WN5    6.74
  7    56925      7 18 29.2     -13 13 01     WN4   11.74
110   165688     18 07 57.0     -19 23 56     WN6    9.81
111   165763     18 08 28.5     -21 15 11     WC5    7.68
113   168206     18 19 07.4     -11 37 58     WC8    9.18
123   177230     19 03 59.0     -04 19 02     WN8   10.88
127   186943     19 46 15.9     +28 16 19     WN4   10.19
128   187282     19 48 34.2     +18 11 32     WN4   10.50
132   190002     20 01 41.8     +32 34 40     WC6   11.55
133   190918     20 05 57.3     +35 47 17     WN4    6.78
134   191765     20 10 14.2     +36 10 35     WN6    8.02
135   192103     20 11 53.5     +36 11 51     WC8    8.51
136   192163     20 12 06.5     +38 21 17     WN6    7.44
137   192641     20 14 31.8     +36 39 39     WC7    7.95
138   193077     20 17 00.0     +37 25 23     WN5    8.06
139   193576     20 19 32.4     +38 43 54     WN5    8.27
140   193793     20 20 28.1     +43 51 17     WC7    6.88
141   193928     20 21 31.8     +36 55 13     WN6    9.74
143   195177     20 28 24.3     +38 36 55     WC5   12.32
148   197406     20 41 21.6     +52 35 16     WN7   10.30
152   211564     22 16 35.7     +55 36 55     WN3   11.62
153   211853     22 18 45.6     +56 07 35     WN6    9.03
154   213049     22 27 17.7     +56 15 12     WC6   10.94
155   214419     22 36 54.0     +56 54 21     WN7    8.86
157   219460     23 15 12.6     +60 27 01     WN4   10.13

The spectral data were reduced in the standard manner using Iris and VisualSpec. The instrumental response function was removed from target spectra by using standard star spectra. The relative flux is normalized at the wavelength 6630 angstroms.


WR1

Instrument: Takahashi FS-128 apochromatic refractor + a R=1000 spectrograph (sample of 2.88 A/pixel). Click here for a description of the spectrograph used.




      
WR1.DAT


WR133

WR133 spectrum acquired with the spectr'aude spectrograph and a Takahashi FSQ-106 refractor - dispersion of 4.00 A/pixel:

 

 


WR135

Left,  the WR135 spectrum carried out with the 200 lines/mm grating associated with a prism of 3°57 ' in order to forme a grism. The unit is placed 63 mm in front of the CCD surface. Note that it is possible to obtain quite  fine emission lines to the detriment of the quality of the zero order image. Right, the grating and the prism are slipped into a filters older interposing between a 190-mm telescope and the Audine CCD camera:

 

The spectrum of WR135 (sampling of 16.9 A/pixel):


WR136

Grism assembly (16.4 A/pixel) + a 190-mm flat-field camera + Audine camera Kodak KAF-0400.
 


WR137

Instrument: Takahashi FS-128 apochromatic refractor + a R=1000 spectrograph (sample of 2.88 A/pixel). Click here for a description of the spectrograph used.




WR137_2.DAT


 WR140

Grism assembly (16.4 A/pixel) + a 190-mm flat-field camera + Audine camera Kodak KAF-0400.
 

 

WR140 specrum taken with the spectr'aude and a Takahashi FSQ-106 refractor - dispersion of 4.00 A/pixel: