Absolute flux calibrated spectra

Dear Enrique,

   many thanks for using the ESO archive services.

There are different ways to achieve your goal:

• If you are interested in a specific data collection, for instance the X-Shooter Spectral Library (XSL), you should refer to the associated release description, that contains information on how the data are reduced and the level of the calibration achieved.
• It is possible to run a TAP query to obtain the list of all calibrated data by setting a WHERE condition on the o_calib_status column and requiring spectrum as dataproduct_type:

  SELECT TOP 10 * 
  FROM ivoa.ObsCore 
  WHERE 
      o_calib_status = 'absolute' AND 
      dataproduct_type = 'spectrum'

• If you are interested in a specific target, you can take advantage of the unofficial ESOAsg python package. For instance, if you want to collect all calibrated spectra present in the ESO archive associated with the star HD 057060, you can run:

  from ESOAsg import archive_observations
  from astropy.coordinates import SkyCoord
  
  # Define star position
  star_position = SkyCoord.from_name('HD 057060')
  
  # Get information on all spectra collected within 5" from the star
  eso_spectra = archive_observations.query_from_radec(star_position, radius=5., columns=['dp_id', 'instrument_name', 'o_calib_status'], data_types='spectrum')
  
  # Select absolute flux calibration
  cond_absolute = (eso_spectra['o_calib_status'] == 'absolute')
  
  # Download the data
  archive_observations.download(eso_spectra['dp_id'][cond_absolute])
  

  Note that this is equivalent to run this TAP query and download the retrieved dp_ids
  

Please let us know if this answer your question. We can also provide a more tailored feedback, but we will need some more details on the goal you need to achieve.

Enjoy your data!

The ESO Archive Science Group