# 2.2.5 Spectral libraries

Author(s): Paola Sartoretti

The spectral libraries that are used in the Universe Model are described in details in Sordo et al. (2011). They can be either in low resolution (LR) for photometry and BP/RP simulations or high resolution (HR) for RVS simulations. For the catalogues produced in this data release, we only needed stellar photometry simulations, which uses the LR version of:

1. 1.

the Basel2 library (Lejeune et al. 1997)
It contains 8286 spectra covering the wavelength range 9.1 to 16000 nm with a mean resolution of 2 nm in the visible. The ranges of fundamental parameters are: $T_{\rm eff}$: between 2000 and 50000 K, $\log g$ between $\sim$ -1 and 5.5, and [Fe/H] between +1.0 and -5.0.

2. 2.

the Marcs library (Gustafsson et al. 2008)
It contains 1778 spectra. $T_{\rm eff}$ range between 4000 and 8000K (step 250K), $\log g$ between -1.0 to 5.0 (step 0.5), and [Fe/H] between -5.0 and 1.0 (with a variable step from 1.0 to 0.25 dex).

3. 3.

the A-stars library (Shulyak et al. 2004)
It contains 972 spectra, dependent on $T_{\rm eff}$, $\log g$ and [Fe/H]

4. 4.

the OB-stars library (Bouret et al. 2008)
It contains 213 spectra, only dependent on $T_{\rm eff}$, $\log g$; [Fe/H] is fixed to the solar value.

5. 5.

the WD-stars library (Castanheira et al. 2006)
It contains 129 spectra, only dependent on $T_{\rm eff}$, $\log g$; [Fe/H] is fixed to the solar value.

6. 6.

the Phoenix library (Brott and Hauschildt 2005)
It contains contains 4575 spectra. The effective temperatures range between 3000 and 10000K, with steps of 100K from 3000K to 7000K and of 200K from 7000K to 10000K. The steps in $\log g$ are of 0.5 and the grid start at different values depending to $T_{\rm eff}$: at -0.5 (between 3000K and 5700K), at 0 (between 5800K and 6200K), at 0.5 (between 6300K and 7000K), at 1 (between 7200K to 8800K) and at 1.5 (from 9000K to 10000K). The $\log g$ grid ends at 5.5 for all temperatures. The [Fe/H] ranges from -2.5 to +0.5 with steps of 0.5.

7. 7.

the Balmer emission lines (Be) library (Martayan et al. 2008)
It contains 174 spectra. The $T_{\rm eff}$ are of 15000 K, 20000 K and 25000 K; $\log g$ =4 and [Fe/H] = 0. The parameter used to indicate the strength of the emission features is the ratio between the envelope radius and the stellar radius ($R\_env/R\_star$).

8. 8.

the WR library (Martayan et al. 2008)
It contains 43 spectra, only dependent on $T_{\rm eff}$, $\log g$; [Fe/H] is fixed to the solar value.

The association of a spectrum to a source is done based on a minimum distance method between the parameters of the source and those of the spectrum.