We present a multi-wavelength ( X-ray to optical ) analysis , based on non-local thermodynamic equilibrium photospheric+wind models , of the B0 Ia-supergiant : \epsilon Ori .
The aim is to test the consistency of physical parameters , such as the mass-loss rate and CNO abundances , derived from different spectral bands .
The derived mass-loss rate is \hbox { $ \dot { M } $ } / \sqrt { f _ { \infty } } \sim 1.6 \times 10 ^ { -6 } M _ { \odot } yr ^ { -1 } where f _ { \infty } is the volume filling factor .
However , the S iv \lambda \lambda 1062,1073 profiles are too strong in the models ; to fit the observed profiles it is necessary to use f _ { \infty } < 0.01 .
This value is a factor of 5 to 10 lower than inferred from other diagnostics , and implies \hbox { $ \dot { M } $ } \lesssim 1 \times 10 ^ { -7 } M _ { \odot } yr ^ { -1 } .
The discrepancy could be related to porosity-vorosity effects or a problem with the ionization of sulfur in the wind .
To fit the UV profiles of N v and O vi it was necessary to include emission from an interclump medium with a density contrast ( \rho _ { cl } / \rho _ { ICM } ) of \sim 100 .
X-ray emission in H-He like and Fe L lines was modeled using four plasma components located within the wind .
We derive plasma temperatures from 1 \times 10 ^ { 6 } to 7 \times 10 ^ { 6 } K , with lower temperatures starting in the outer regions ( R _ { 0 } \sim 3-6 R _ { * } ) , and a hot component starting closer to the star ( R _ { 0 } \lesssim 2.9 R _ { * } ) .
From X-ray line profiles we infer \hbox { $ \dot { M } $ } < 4.9 \times 10 ^ { -7 } M _ { \odot } yr ^ { -1 } .
The X-ray spectrum ( \geq 0.1 kev ) yields an X-ray luminosity L _ { X } \sim 2.0 \times 10 ^ { -7 } L _ { bol } , consistent with the superion line profiles .
X-ray abundances are in agreement with those derived from the UV and optical analysis : \epsilon Ori is slightly enhanced in nitrogen and depleted in carbon and oxygen , evidence for CNO processed material .