"If I could start my life over again, I would undertake spectral classification at resolution no worse than 1 A, and as much better than that as possible."

P.C. Keenan 1984

This is the home page of the NGSL UVES project (PI: Dave Silva). Data have been collected at the UVES high-resolution echelle spectrograph on the 8.2m UT2/Kueyen telescope at ESO's VLT.

These data have been collected over five periods (P71-P74, P76 = April 2003 - March 2005; September 2005 - March 2006). Find below an overview of results per target, OB and DATE.

The data have been processed from the standard UVES pipeline products. Due to problems with high S/N, the data have been extracted in AVERAGE mode. Data are flux-calibrated. Find more about the reduction by the UVES pipeline here.

The further processing ('NGSL pipeline') has been:
- organize per target (usually OB twins)
- average multiple exposures from same OBs into one final product per setup
- do a fine-correction of flux scale to minimize steps between setups
- determine S/N ratio
- reduce wavelength scale to *common* (stellar) rest system
- indicate telluric features

Telluric stars have been measured occasionally. They are marked by their target name prefixed by a string containing the year and the month of their observation. For instance, T0306_HD_142919 stands for "telluric standard HD_142919 measured in 2003-06". Spectra of telluric standards have been treated exacly the same way as the NGSL target stars. They have been used to build the table of telluric absorption lines which is the basis for the telluric markers in the spectral plots red of 5800 A.

Known issues:
Precision of flux calibration: the master response curves are collected typically for a year and can't reflect faster changes of instrument response. There is often a step between the 580L and 580U settings.

Also, the flux calibration can be relative at most since a slit width of about 1 arcs has been used, under varying seeing conditions. This is a C-class, 'filler' programme harvesting telescope time with mediocre ambient conditions.

TARGET NAME: name of object
SpT ... Cat: stellar parameters as taken from catalogue 'Cat'
OB ID: technical OB_ID name(s)
DATE: date of observation