Fixed Owens (1967) model

AstroAtmosphere/refractivityModels.py

@@ -174,9 +174,10 @@ def Edlen1966(l, T=288.15, p=101325, RH=0, CO2=300, f=None):
 def Owens(l, T=288.15, p=101325, RH=0):
 	'''
 		From Owens, 1967
-		Equation 32
+		Equations 29 to 31
-		Note that the pressure P and H are in torricelli (Torr),
+		
-		however, this is almost precisely 1 Torr = 1 mmHg
+		Code heavily based on ScopeSIM (https://scopesim.readthedocs.io/)
+		and http://www.caha.es/newsletter/news03b/pedraz/newslet.html
 
 		Parameters
 		----------
@@ -194,10 +195,27 @@ def Owens(l, T=288.15, p=101325, RH=0):
 		n 	: 	float
 			Refractive index of atmospheric air at the given conditions
 	'''
-	P = hPa2mmHg(p/100)
+	# Calculation from ScopeSIM.effects.atmospheric_refraction()
-	T = K2C(T)
+	pres = p / 100 # from mbar to Pa
-	s = 1 / l
+	Ps = -10474. + 116.43 * T - 0.43284 * T**2 + 0.0005384 * T**3
-	R = 8342.13 + 2406030 / (130 - s**2) + 15997 / (38.9 - s**2) * (P/720.775) * ((1 + P * (0.817 - 0.0133) * 1e-6)/(1 + 0.0036610*T)) - RH * (5.722 - 0.0457*s**2)
+	Pw = Ps * RH / 100.
+	Pa = pres - Pw
+
+	# Wavenumber s
+	s = 1. / l
+
+	# Density factor of dry air, eq. 30
+	Da = (Pa / T) * (1. + Pa * (57.9E-8 - 0.0009325 / T + 0.25844 / T**2))
+	
+	# Density factor of moist air, eq. 31
+	Dw = (Pw / T) * (1. + Pw * (1. + 3.7E-4 * Pw) *
+					 (-2.37321E-3 + 2.23366 / T - 710.792 / T**2 +
+					  77514.1 / T**3))
+
+	# Combining the two into eq. 29
+	na = Da * (2371.34 + 683939.7 / (130. - s**2) + 4547.3 / (38.9 - s**2))
+	nw = Dw * (6487.31 + 58.058 * s**2 - 0.7115 * s**4 + 0.08851 * s**6)
+	R = na + nw
 	n = R/1e8 + 1
 	return n
 

README.md

@@ -110,7 +110,7 @@ Input parameters for the spherical atmosphere models (all but the first):
 - xc - CO2 density              [ppm]
 - lat - Latitude                [deg]
 - h - Height above sea level    [m]
-- l - Wavelength(s)             [um]
+- l - Wavelength(s)             [μm]
 - z - Zenith angle              [deg]
 
 An example - To calculate the atmospheric refraction we set up a `refraction()` object. This requires the latitude and altitude of the observer. The atmospheric dispersion is calculated similarly, but by exchanging the `refraction()` object by a `dispersion()` object and parsing two refractive indices into the `cassini()` function.
@@ -195,6 +195,7 @@ Included are
 | Bonsch & Potulski (1998) | `BonschPotulski()` | Allows for any temperature, pressure, humidity and CO2 density. |
 | Birch & Downs (1994) | `BirchDowns()` | Only at standard atmosphere. Function requires wavelength only. |
 | Peck & Reeder (1972) | `PeckReeder()` | Only at standard atmosphere. Function requires wavelength only. |
+| Mathar (2006) | `Mathar()` | Allows for temperature, pressure and humidity specification. Works best at wavelengths above 1.4 μm. |
 | Hohenkerk & Sinclair (1985) | `HohenkerkAndSinclair()` | Based on Barrell & Sears equation. Generally, gives slightly larger values.|
 | Hohenkerk & Sinclair (1985) | `slalib()` | Uses pySLALIB to retrieve the refractive index at standard atmospheric conditions.|
 
@@ -226,6 +227,7 @@ Presently, several observatories are known. These can all be found in the `obser
 | Roque de los Muchachos Observatory (La Palma) | `LA_PALMA`        | GTC, INT, WHT, NOT, and others.               |
 | La Silla Observatory                          | `LA_SILLA`        | ESO 3.6m telescope, NTG, BlackGEM and others. | 
 | Las Campanas Observatory                      | `LAS_CAMPANAS`    | Site of the future GMT.                       |
+| Mauna Kea Observatory (Hawaii)                | `MAUNA_KEA`       | Location of Keck, Subaru, Gemini North and others.|
 
 ## Other
 

setup.py

@@ -21,14 +21,14 @@ def setup_package():
     # write_version_py()
 
     setup(name='AstroAtmosphere',
-          version='1.4.1',
+          version='1.5',
           description='Collection of equations for refractive index, refraction and dispersion calculations of atmospheric air.',
           long_description=__readme__,
           long_description_content_type='text/markdown',
           author='Joost van den Born',
           author_email='born@astron.nl',
           url='https://gitlab.astro-wise.org/micado/atmosphericmodel',
-          download_url='https://gitlab.astro-wise.org/micado/atmosphericmodel/-/archive/v1.4.1/atmosphericmodel-v1.4.1.tar.gz',
+          download_url='https://gitlab.astro-wise.org/micado/atmosphericmodel/-/archive/v1.5/atmosphericmodel-v1.5.tar.gz',
           license='GNU General Public License v3',
           data_files = [('',['LICENSE.txt'])],
           package_dir={'AstroAtmosphere': 'AstroAtmosphere'},