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--- spectral_class_a [2019/12/24 16:03]
tstibor created
+++ spectral_class_a [2020/12/09 15:27] (current)
@@ Line 2: / Line 2: @@
 ===== Puerto Naos (La Palma) 2019-10-28 =====
 ==== Instrumental Response ====
-{{:instrumental_response_20191028_8629.png?800|}}
+{{: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?800|}}
+{{: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?800|}}
+{{:multiplot.png|}}
-Created colored spectra image
+D-spectra image
+{{:alplyr-crop.png|}}
+and inverted
+{{:alplyr-crop-negate.png|}}
+Created artificial colored 2D-spectra image
 {{:alplyr--profil-1c_sel_color.jpg|}}
@@ Line 26: / Line 31: @@
 </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
+$R = \frac{1}{4} (\frac{4860}{65.4526604596} + \frac{4340}{54.6684579023} + \frac{4101}{47.6019613648} + \frac{3966}{44.722014838}) = 82.11821$

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