J/A+A/555/A131 Fundamental parameters of star clusters in the LMC (Palma+, 2013) ================================================================================ A sample of relatively unstudied star clusters in the Large Magellanic Cloud: fundamental parameters determined from Washington photometry. Palma T., Claria J.J., Geisler D., Piatti A.E., Ahumada A.V. =2013A&A...555A.131P ================================================================================ ADC_Keywords: Magellanic Clouds ; Clusters, open ; Photometry, CMT1T2V Keywords: techniques: photometric - galaxies: star clusters: general - galaxies: individual: LMC Abstract: To enlarge our growing sample of well-studied star clusters in the Large Magellanic Cloud (LMC), we present CCD Washington CT1 photometry to T1~23 in the fields of twenty-three mostly unstudied clusters located in the inner disc and outer regions of the LMC. We estimated cluster radii from star counts. Using the cluster Washington (T1,C-T1) colour-magnitude diagrams, statistically cleaned from field star contamination, we derived cluster ages and metallicities from a comparison with theoretical isochrones of the Padova group. Whenever possible, we also derived ages using delta T1 - the magnitude difference between the red giant clump and the main sequence turn off - and estimated metallicities from the standard giant branch procedure. We enlarged our sample by adding clusters with published ages and metallicities determined on a similar scale by applying the same methods. We examined relationships between their positions in the LMC, ages and metallicities. We find that the two methods for age and metallicity determination agree well with each other. Fourteen clusters are found to be intermediate-age clusters (1-2Gyr), with [Fe/H] values ranging from -0.4 to -0.7. The remaining nine clusters turn out to be younger than 1Gyr, with metallicities between 0.0 and -0.4. Our 23 clusters represent an increase of ~30% in the current total amount number of well-studied LMC clusters using Washington photometry. In agreement with previous studies, we find no evidence for a metallicity gradient. We also find that the younger clusters were formed closer to the LMC centre than the older ones. Description: After a careful revision of the Washington wide-field images of 21 LMC regions (see Sect. 3), we selected those star clusters located outside the bar for the present study that appeared to be unstudied or were only poorly studied. Our final sample includes a total of 23 mostly unstudied clusters, eleven of which lie in the inner disc of the LMC but outside the bar. The remaining twelve are located in the outer region (Fig. 1). We obtained images for 23 star clusters on the nights of 2000 December 29-30, with the MOSAIC II camera of the Victor Blanco 4-m telescope (scale 0.27 arcsec/pixel) at Cerro Tololo Inter-American Observatory (CTIO), Chile. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file table1.dat 93 23 Observed star clusters in the LMC tab3_1.dat 60 21780 CT1 data of stars in the field of SL33/SL41 tab3_2.dat 60 27204 CT1 data of stars in the field of KMHK123 tab3_3.dat 60 20371 CT1 data of stars in the field of KMHK128 tab3_4.dat 60 30083 CT1 data of stars in the field of LW69 tab3_5.dat 60 22935 CT1 data of stars in the field of KMHK151 tab3_6.dat 60 28397 CT1 data of stars in the field of SL54 tab3_7.dat 60 24789 CT1 data of stars in the field of SL73 tab3_8.dat 60 31974 CT1 data of stars in the field of SL72 tab3_9.dat 60 62663 CT1 data of stars in the field of BSDL594 tab3_10.dat 60 57755 CT1 data of stars in the field of BSDL654/665 tab3_11.dat 60 57359 CT1 data of stars in the field of BSDL675 tab3_12.dat 60 74286 CT1 data of stars in the field of HS130 tab3_13.dat 60 54351 CT1 data of stars in the field of BSDL761 tab3_14.dat 60 47795 CT1 data of stars in the field of BSDL779 tab3_15.dat 60 51294 CT1 data of stars in the field of HS156 tab3_16.dat 60 45068 CT1 data of stars in the field of HS178 tab3_17.dat 60 17372 CT1 data of stars in the field of LW211 tab3_18.dat 60 30792 CT1 data of stars in the field of C11 tab3_19.dat 60 30197 CT1 data of stars in the field of BSDL3158 tab3_20.dat 60 14899 CT1 data of stars in the field of KMHK1702 tab3_21.dat 60 12859 CT1 data of stars in the field of SL870 -------------------------------------------------------------------------------- See also: J/A+A/501/585 : CT1 photometry in five LMC star clusters (Piatti+, 2009) J/MNRAS/389/678 : Cat. of extended objects in Magellanic Clouds (Bica+, 2008) J/AJ/117/238 : LMC extended catalog (Bica+, 1999) J/AJ/116/723 : LMC star clusters ages and metallicity (Bica+ 1998) J/A+AS/110/533 : Clusters and field stars in LMC. I. (Linde+, 1995) Byte-by-byte Description of file: table1.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 8 A8 --- Name Star cluster name (1) 10- 36 A27 --- OName Other designation(s) 38- 39 I2 h RAh Hour of right ascension (J2000) 41- 42 I2 min RAm Minute of right ascension (J2000) 44- 45 I2 s RAs Second of right ascension (J2000) 47 A1 --- DE- Sign of declination (J2000) 48- 49 I2 deg DEd Degree of declination (J2000) 51- 52 I2 arcmin DEm Arcminute of declination (J2000) 54- 55 I2 arcsec DEs Arcsecond of declination (J2000) 57- 63 F7.3 deg GLON Galactic longitude 65- 71 F7.3 deg GLAT Galactic latitude 73- 76 F4.2 arcmin r Cluster radius from Bica et al. (2008, Cat. J/MNRAS/389/678) 78- 80 I3 pix Rad Cluster radius derived in the current study in pixels 82- 85 F4.1 pc Rad2 Cluster radius derived in the current study in parsecs 87- 93 A7 --- Tab Table number for the corresponding stars data; column added by CDS -------------------------------------------------------------------------------- Note (1): Cluster identifications from: SL = Shapley & Lindsay (1963IrAJ....6...74S, <[SL63] NNN> in Simbad); LW = Lynga & Westerlund (1963MNRAS.127...31L, in Simbad); HS = Hodge & Sexton (1966AJ.....71..363H, <[HS66] NNNA> in Simbad); C = Hodge (1975IrAJ...12...77H, <[H75] NN> in Simbad); H88 = Hodge (1988PASP..100.1051H, for Simbad); KMHK = Kontizas et al. (1990A&AS...84..527K, in Simbad); LOGLE = Pietrzynski et al. (1998AcA....48..175P, 1999AcA....49..521P, in Simbad); BSDL = Bica et al. (1999, Cat. J/AJ/117/238, or <[SL63] NNNA> in Simbad). -------------------------------------------------------------------------------- Byte-by-byte Description of file: tab3_*.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 6 I6 --- Seq Sequential number within the field 8- 15 F8.3 pix Xpos X position (1) 17- 24 F8.3 pix Ypos Y position (1) 28- 33 F6.3 mag T1mag T1 magnitude 38- 42 F5.3 mag e_T1mag rms uncertainty on T1mag 46- 51 F6.3 mag C-T1 C-T1 colour index 56- 60 F5.3 mag e_C-T1 rms uncertainty on C-T1 -------------------------------------------------------------------------------- Note (1): The dimension of each field region is 2048x4092 pixels. 1 pix = 0.27arcsec. -------------------------------------------------------------------------------- Acknowledgements: Tali Palma: tali{at}mail.oac.uncor.edu ================================================================================ (End) Tali Palma [Cordoba Univ.], Emmanuelle Perret CDS 03-Jul-2013