The Chandra Archive of Hot Stars
Because of the pathetically small effective area of the gratings, only a handful of single OB stars can produce high-quality spectra maybe a dozen total; we will look at several representative single OB stars
Beta Cep var.
1200
~5(-9)
B0.5 IV
b Cru
Same, but more so
1800
5(-8)
B0.5 Ve
g Cas
Unusually X-ray bright and hard
1500
3(-8)
B0 V
t Sco
1100 G dipole magnetic field
2500
4(-7)
O7 V
q1 Ori C
2000
1(-6)
O9.7 I
d Ori
1860
1(-6)
O9.5 II
z Ori
2500
2.5 (-6)
O4 
z Pup
comments
Vinf
Mdot
Sp. Ty.
Star