Photometric study of the open cluster NGC 225

Yalyalieva L., Glushkova E., Carraro G.,Ikonnikova N.,Gasymov D.

Astrophysical Bulletin, in press.

Abstract:
     NGC 225 is a young moderately populated cluster with discrepant age, 
	 distance, and colour excess estimates reported by different authors. 
	 We combine our photometry with the data from large surveys (2MASS, WISE, 
	 Pan-STARRS) to derive the parameters of NGC 225 and study the extinction 
	 law in the near infrared in the direction of the cluster. We use 
	 theoretical isochrones to infer the colour excess E(B-V)=0.29 +- 0.01, 
	 distance D=667 +- 18 pc, and age = 100-160 Myr. We fit extinction in the 
	 infrared by a power-law relation, lambda^(-alpha), and find 
	 alpha = 2.16 +- 0.34.

Description:
	 Catalogue contains U, B, V, Rc, Ic photometry for NGC 225 cluster members 
	 within a field of about 22 arcmin x 22 arcmin from the cluster centre. 

File Summary:
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  FileName        Lrecl  Records   Explanations
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  Readme.txt         80        .   This file
  ngc225_phot.dat    98       55   U,B,V,Rc,Ic photometry
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Byte-by-byte description of file ngc225_phot.dat
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  Bytes Format Units   Label   Explanations
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   1- 4  A4    ---     N       Star index
   7- 8  I2    h       RAh     Right ascension (J2000.0)
 10- 11  I2    min     RAm     Right ascension (J2000.0)
 13- 17  F5.2  s       RAs     Right ascension (J2000.0)
     20  A1    ---     DEC-    Declination sign (J2000.0)
 21- 22  I2    deg     DECd    Declination (J2000.0)
 24- 25  I2    arcmin  DECm    Declination (J2000.0)
 27- 30  F4.1  arcsec  DECs    Declination (J2000.0)
 33- 37  F5.2  mag     V       V magnitude
 40- 43  F4.2  mag     eV      error of V magnitude
 46- 49  F4.2  mag     BV      colour B-V
 52- 55  F4.2  mag     eBV     error of colour B-V
     58  A1    ---     UB-     colour U-B sign
 59- 62  F4.2  mag     UB      colour U-B
 65- 68  F4.2  mag     eUB     error of colour U-B
 71- 74  F4.2  mag     VI      colour V-I
 77- 80  F4.2  mag     eVI     error of colour V-I
 83- 86  F4.2  mag     RI      colour R-I
 89- 92  F4.2  mag     eRI     error of colour R-I
 95- 98  F4.2  ---     prob    membership probability
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