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 Data Documentation : Wide Binaries from GAIA EDR3: preference for GR over MOND ?
 arxiv : https://arxiv.org/abs/2205.02846
 DOI : https://doi.org/10.21105/astro.2205.02846
 Authors : Charalambos Pittordis; William Sutherland

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Overview
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This is a README file for the wide-binary sample selected from GAIA EDR3 for the Pittordis & Sutherland (2023) 
 paper referenced above. 

The major selection criteria are stars with magnitude G < 17, distance < 300 pc and abs(galactic latitude) > 15 deg; and
binary projected separations < 50 kAU, projected velocity difference < 3 km/s, and distances consistent at min(4 sigma, 8 pc). 
Various additional quality cuts are applied; see above paper for details.  

The data table contains both the columns from Gaia Data Release Documentation, 
see https://gea.esac.esa.int/archive/documentation/GDR2/Gaia_archive/chap_datamodel/sec_dm_main_tables/ssec_dm_gaia_source.html  
AND 
additional columns that were generated from the EDR3 data for the analysis.

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Suffix Description
-------------------
Within the dataset, you will notice the suffix _i1 and _i2 appended to the columns from GAIA EDR3. 
These represent the original GAIA values for star 1 and 2 of each binary system,

		Suffix _i1 = for star 1 of binary system.
		Suffix _i2 = for star 2 of binary system. 

Star labels 1 and 2 are assigned in order of increasing Dec, and do not represent
primary or secondary by mass. 
		
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Generated Columns Description
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indx 				:  General index column, assigning each star with an integer unique within this table. 
rp_AU 				:  Binary projected separation between star _i1 and star _i2 ; assumes both stars at mean of 2 distances; units [AU]
rp_m 				:  Binary projected separation between star _i1 and star _i2 in units [m]
rp_pc 				:  Binary projected separation between star _i1 and star _i2 in units [pc]
distance			:  Distance to star, i.e. 1000/parallax [mas], parallax from EDR3, units [pc]
Gmag				:  Same as the Gaia EDR3 column "phot_g_mean_mag"
AbsGmag				:  The Absolute Gaia Magnitude, computed using Johnson-Cousins relation, see section 2.6 eq(2) in journal.
Mass_MGedr3_kg 		:  Mass of star, using Mass-Magnitude relationship as shown in section 2.6 eq(3) in journal, using AbsGmag values, units [kg] 
Mass_MGedr3_Msun	:  Mass of star, using Mass-Magnitude relationship as shown in section 2.6 eq(3) in journal, using AbsGmag values, units [Msun]
VcNrp_MassEDR3_kms 	:  Circular Newtonian velocity at current projected separation, see section 2.4 eq(4), using Mass_MGedr3_kg and rp_m values, units [km/s]
Dvp_kms				:  The projected/transverse velocity difference between star _i1 and star _i2; assumes both stars are at the unweighted mean of the two distances. Units [km/s]
sigma_distance 		:  The uncertainty on distance to star, e.g., (1000/parallax^2)*parallax_error, parallax and parallax given by Gaia Data; unit [pc] 
Dsigma_distance 	:  Standard deviation of distance difference between star _i1 and star _i2, i.e. sqrt( sigma_distance_i1^2 + sigma_distance_i2^2 ) ; unit [pc] 
u_EDR3				:  See section 2.5, the parameter used for Data quality cuts on binary candidates, e.g., sqrt(chi2/nu)
DataQualityCut_EDR3	:  See section 2.5, the parameter used for Data quality cuts on binary candidates, e.g., sqrt(chi2/nu) <= 1.2*(max(1, exp(-0.2*(Gmag-19.5))))

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Gaia Columns Description
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The remaining columns not described above are the native Gaia EDR3 columns, where their description is found via
https://gea.esac.esa.int/archive/documentation/GDR2/Gaia_archive/chap_datamodel/sec_dm_main_tables/ssec_dm_gaia_source.html 

with an additional suffix _i1 or _i2 denoting star 1 or star 2.