===== Puerto Naos (La Palma) 2019-10-28 =====
==== Instrumental Response ====
{{:instrumental_response_20191028_8629.png|}}
==== Alpha Lyra (Vega) ====
[[http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=vega|SIMBAD Astronomical Database]]
{{:alpha_lyra_vega_20191028_8629.png|}}

Comparison multiplot with Christian Buil's [[http://www.astrosurf.com/buil/isis/download/isis_database_v8.zip|library of reference data.]]
{{:multiplot.png|}}

2D-spectra image
{{:alplyr-crop.png|}}
and inverted
{{:alplyr-crop-negate.png|}}

Created artificial colored 2D-spectra image
{{:alplyr--profil-1c_sel_color.jpg|}}

Determination of the surface temperature
<code>
spc_ajustplanck alplyr--profil-1c_sel
# Le continuum vaut 0.303090909091
# Les limites non nulles sont 0 ; 321
# l2= 345.385, h1= 1.38461, len=322 ; # norm2= 690.77 ; # Calcul de l'ajustement...
# T=1000 ; # T=2000 ; # T=3000, RMS=0.37777840488 ; # T=4000 ; # RMS=0.142109035409 ; # T=5000 ; # RMS=0.109888603881 ; # T=6000 ; # RMS=0.0952562081394 ; # T=7000 ; # RMS=0.0887952608898 ; # T=8000 ; # RMS=0.086230311707 ; # T=9000 ; # RMS=0.0855422553528 ; # T=10000 ; # RMS=0.0857544683719 ; # 
# Température déterminée : 0.086230311707>RMS=0.0855422553528<0.0857544683719
# Calcul de la courbe de Planck de l'UV au rouge...
# Température trouvée : 9000 K
# 9000
</code>
{{::spc_ajustplanck_alplyr--profil-1c_sel.png?800|}}
==== Resolving Power & Resolution ====
The //resolving power// is defined as $R = \frac{\lambda}{\Delta \lambda}$, where $\lambda$ is the wavelength and $\Delta \lambda$ the wavelength interval defined as the //spectral resolution//.
The spectral resolution is the smallest wavelength interval that can be distinguished and is expressed in
wavelength units as Å or nanometers. In addition, it can be expressed as the $\Delta \lambda = \text{FWHM}_{\text{Instrument}} = \frac{\lambda}{R}$.

The FWHM values are measured with SpcAudace at
<code>
spc_fwhm alplyr--profil-1c_sel 3934 3990 a
# 44.722014838 6.52887092647
</code>
<code>
spc_fwhm alplyr--profil-1c_sel 4056 4143 a
# 47.6019613648 7.1041365302
</code>
<code>
spc_fwhm alplyr--profil-1c_sel 4304 4416 a
# 54.6684579023 4.66692282694
</code>
<code>
spc_fwhm alplyr--profil-1c_sel 4825 4905 a
# 65.4526604596 6.58084006378
</code>
and yields a mean $\text{FWHM}_{\text{Instrument}}$ value of $\Delta \lambda = 53.11127$ Å and a mean resolving power of
$R = \frac{1}{4} (\frac{4860}{65.4526604596} + \frac{4340}{54.6684579023} + \frac{4101}{47.6019613648} + \frac{3966}{44.722014838}) = 82.11821$