Subject: broad emission-like line feature in the JEM-X spectra

   Good afternoon!
  We observe broad (~2-3 keV) emission-like line feature at ~7-8 keV in
the JEM-X spectra (for OSA 4.1 and 4.2). What is the reason for it? And how
should we deal with it?

  Thanks in advance,
   Filippova Ekaterina.


Subject: #helpdesk/10058

 Dear Dr. Oxborrow,
Thank you very much for your answer.
Following your invitation to discuss this problem, 
I send you three spectra, where this feature presents.
Also  files are attached, where you can find my approximation of these
spectra. This feature is clearly seen in the residuals and can be
modeled with 'gaus' or 'wabs'.
It is difficult to decide what model should be used for correct
approximation. 

 For Vela X-1 spectrum  have been used 18 SCWS from 85 -- 88 orbits; for
CenX-3(I) -- 117 SCWS from 30,46,66,76,77,85,88 orbits: for CenX-3(II)
-- 22 SCWS from 78,85,86,91 orbits; for SMC X-1 -- 25 SCWS from 94,95
orbits.
 
  You could see that in the SMC X-1 spectrum this feature can't be
interpred as Fe-emission line (I fixed E_{cut} and E_{fold} at the
values received from the approximation of JEM-X and IBIS spectra
together). In the Vela X-1 it can be interpred as Fe-emission line
hardly.
   But in the CenX-3 spectra the Fe-emission lines seem to present.
Although in one case (I) the low limit for its width is 0, and in
another case (II) the central energy of its is 7.1 keV.
Should I concider them as real one?

 Filippova Ekaterina.