Change alpha_ox to det_alpha_ox, to use the empirical alpha_ox-L_2500 relation

pcigale/sed_modules/xray.py

@@ -9,7 +9,7 @@
 X-ray module
 =============================
 
-This module implements the X-ray emission from the galaxy and AGN corona.
+This module implements the X-ray emission from galaxy and AGN corona.
 
 """
 
@@ -31,15 +31,15 @@ class Xray(SedModule):
         ("gam", (
             "cigale_list()",
             "The photon index (Gamma) of intrinsic X-ray spectrum.",
-            1.6
+            1.7
         )),
         ("det_alpha_ox", (
             "cigale_list()",
-            "Deviation of alpha_ox from the empirical alpha_ox(Lnu_2500A) relation (Just et al. 2007),",
-            "defined as det_alpha_ox = alpha_ox - alpha_ox(Lnu_2500A).",
-            "Common (~3sigma) range of det_alpha_ox is [-0.3, 0.3]",
-            "Note: alpha_ox is the power-law slope connecting L_nu at rest-frame 2500 A and 2 keV, ",
-            "defined as alpha_ox = 0.3838*log(Lnu_2keV/Lnu_2500A)",
+            "Deviation of alpha_ox from the empirical alpha_ox(Lnu_2500A) relation (Just et al. 2007), "+
+            "defined as det_alpha_ox = alpha_ox - alpha_ox(Lnu_2500A). "+
+            "Common (~3sigma) range of det_alpha_ox is [-0.3, 0.3]. "+
+            "Note: alpha_ox is the power-law slope connecting L_nu at rest-frame 2500 A and 2 keV, "+
+            "defined as alpha_ox = 0.3838*log(Lnu_2keV/Lnu_2500A).",
             0.0
         ))
     ])
@@ -116,6 +116,12 @@ class Xray(SedModule):
         sed.add_info("xray.det_alpha_ox", self.det_alpha_ox)
 
         # Convert det_alpha_ox to alpha_ox
+        # Check if Lnu_2500A is positive
+        if Lnu_2500A>0:
+            alpha_ox = self.det_alpha_ox + -0.137*np.log10(Lnu_2500A*1e7)+2.638
+        else:
+            alpha_ox = -np.inf
+        sed.add_info("xray.alpha_ox", alpha_ox)
 
         # Calculate 0.5-2 keV hot-gas luminosities
         # Mezcua et al. 2018, Eq. 5
@@ -130,7 +136,7 @@ class Xray(SedModule):
             10**(33.276 - 1.503*logT - 0.423*logT**2 + 0.425*logT**3 + 0.136*logT**4)
 
         # Calculate L_lam_2keV from Lnu_2500A
-        Lnu_2keV = 10**(self.alpha_ox/0.3838) * Lnu_2500A
+        Lnu_2keV = 10**(alpha_ox/0.3838) * Lnu_2500A
         L_lam_2keV = Lnu_2keV * self.nu_2keV**2/self.c
         # Calculate total AGN corona X-ray luminosity
         l_agn_xray_total = np.trapz(L_lam_2keV * self.lumin_corona,