15. A2
The line at 
4385 is
stronger relative to Mg II 4481 than in class
A1. The blend at 4129 is
considerably stronger than Mn I 4030-4034.
| Star | MKK | a |  | m | HD |
Aur......... | A2 IV | 05:52 | +44°56' | 2.1 | A0p |
| UMa........ | A2 IV | 10:11 | +43 25 | 3.5 | A2 |
UMa(br).. | A2 V | 13:19 | +55 27 | 2.4 | A2p |
|
Ser.......... | A2 IV | 15:41 | +15 44 | 3.7 | A2 |
Oph......... | A2 V | 17:04 | -15 36 | 2.6 | A2 |
Luminosity differences are shown by the ratios of the blends
4128-4131:
4171-4179, by the intensity of the blend centered near
4555, and by the appearance
of the wings of the hydrogen lines.
 |
| High resolution image |
