Photometry of the Anti-Galactocentric Old Open Clusters
We present the python codes that may be useful for optical photometry and analysis of star clusters. Here, we use a sample case of using four open clusters (OCs) in the Milky Way published in the Astronomical Journal. See Im et al. (2023, AJ, 165, 53) for details on the paper, photometry and analysis.
Figure 1 : B-band images of the open clusters
These are the images of the four OCs showing equatorial and Galactic coordinates.
The python code for making the below figure.
Figure 2 : Error plot for one OC (Czernik 30).
Showing the trend of the errors from the photometry.
The python code for plotting the figure below.
Figures 3, 6, 9, 12 : Spatial distribution of the stars of the OCs from the stellar photometry data.
The python code for plotting the below figures with the data below :
The photometric catalog of Czernik 30 image The photometric catalog of Berkeley 34 image The photometric catalog of Berkeley 75 image The photometric catalog of Berkeley 76 image
Figures 4, 7, 10, 13 : Radial density profile
To get the radius of open clusters.
The python code for plotting the figures below.
The data below are used :
The photometric catalog of Czernik 30 image The photometric catalog of Berkeley 34 image The photometric catalog of Berkeley 75 image The photometric catalog of Berkeley 76 image
Figure 5 : Best fit PARSEC isochrone on V vs (B-V) and V vs (V-I) CMDs.
Best fit PARSEC (PAdova and TRieste Stellar Evolution Code, Bressan et al. 2012, MNRAS, 427, 127) isochrone of Czernik 30.
The python code for plotting the below figure.
The data which we used for below figures:
The photometric catalog - member of Czernik 30 The photometric catalog - field stars of Czernik 30 Best fit isochrone
Figure 8 : Best fit PARSEC isochrone on V vs (B-V) and V vs (V-I) CMDs.
Best fit PARSEC isochrone of Berkeley 34.
The python code for plotting the below figure.
The data which we used for below figures:
The photometric catalog - member of Berkeley 34 The photometric catalog - field stars of Berkeley 34 Best fit isochrone
Figure 11 : Best fit PARSEC isochrone on V vs (B-V) and V vs (V-I) CMDs.
Best fit PARSEC isochrone of Berkeley 75.
The python code for plotting the below figure.
The data which we used for below figures:
The photometric catalog - member of Berkeley 75 The photometric catalog - field stars of Berkeley 75 Best fit isochrone
Figure 14 : Best fit PARSEC isochrone on V vs (B-V) and V vs (V-I) CMDs.
Best fit PARSEC isochrone of Berkeley 76.
The python code for plotting the below figure.
The data which we used for below figures:
The photometric catalog - member of Bekeley 76 The photometric catalog - field stars of Berkeley 76 Best fit isochrone
Figure 15 : Radial metallicity distribution of 236 OCs in the Galactic disk.
(making radial metallicity distribution plot)
You can get the fits format table at the links below :
Dias+02: https://cdsarc.cds.unistra.fr/viz-bin/cat/B/ocl#/article
Netopil+16: https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/585/A150
Donor+20: https://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/159/199
Spina+21: https://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/503/3279
Dias+21: https://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/504/356
The python code for plotting the below figure.