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J/A+A/532/A147    HST photometry in extragalactic star clusters  (Larsen+, 2011)

Resolved photometry of extragalactic young massive star clusters. Larsen S.S., de Mink S.E., Eldridge J.J., Langer N., Bastian N., Seth A., Smith L.J., Brodie J., Efremov Y.N. <Astron. Astrophys. 532, A147 (2011)> =2011A&A...532A.147L
ADC_Keywords: Galaxies, nearby ; Associations, stellar ; Photometry, HST Keywords: open clusters and associations: general - galaxies: star clusters: general - galaxies: spiral - Hertzsprung-Russell and C-M diagrams Abstract: We present colour-magnitude diagrams (CMDs) for a sample of seven young massive clusters in the galaxies NGC 1313, NGC 1569, NGC 1705 and NGC 5236. The clusters have ages in the range 5-50 million years and masses of 105-106M. Although crowding prevents us from obtaining photometry in the inner regions of the clusters, we are still able to measure up to 30-100 supergiant stars in each of the richest clusters, along with the brighter main sequence stars. The resulting CMDs and luminosity functions are compared with photometry of artificially generated clusters, designed to reproduce the photometric errors and completeness as realistically as possible. In agreement with previous studies, our CMDs show no clear gap between the H-burning main sequence and the He-burning supergiant stars, contrary to predictions by common stellar isochrones. In general, the isochrones also fail to match the observed number ratios of red-to-blue supergiant stars, although the difficulty of separating blue supergiants from the main sequence complicates this comparison. In several cases we observe a large spread (1-2mag) in the luminosities of the supergiant stars that cannot be accounted for by observational errors. This spread can be reproduced by including an age spread of 10-30 million years in the models. However, age spreads cannot fully account for the observed morphology of the CMDs and other processes, such as the evolution of interacting binary stars, may also play a role. Description: These tables contain the PSF-fitting photometry in the HST/ACS filters F435W, F555W and F814W for each cluster. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 88 7 Data for the clusters analysed in this paper table4.dat 78 365 Photometry for NGC1569-A table5.dat 78 449 Photometry for NGC1569-B table6.dat 78 489 Photometry for NGC1705-1 table7.dat 78 201 Photometry for NGC1313-F3-1 table8.dat 78 122 Photometry for NGC5236-F1-1 table9.dat 78 98 Photometry for NGC5236-F1-3 table10.dat 78 100 Photometry for NGC7793-F1-1
See also: J/A+AS/139/393 : Young Massive Star Clusters. II. (Larsen, 1999) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 12 A12 --- Cluster Cluster name 14- 15 I2 h RAh Right ascension (J2000) 17- 18 I2 min RAm Right ascension (J2000) 20- 24 F5.2 s RAs Right ascension (J2000) 26 A1 --- DE- Declination sign (J2000) 27- 28 I2 deg DEd Declination (J2000) 30- 31 I2 arcmin DEm Declination (J2000) 33- 36 F4.1 arcsec DEs Declination (J2000) 38- 40 F3.1 Mpc Dist Cluster distance 41 A1 --- r_Dist Distance reference (1) 43- 46 F4.1 mag Vmag V magnitude of cluster 48- 51 F4.2 mag AB Absorption in B band 53- 56 F4.2 [yr] logAge Age of cluster 58- 64 E7.2 Msun Mass Estimated mass of cluster 66 A1 --- l_MTO [~] Limit flag on MTO 67- 70 F4.1 Msun MTO Main sequence turn-off mass 72- 76 F5.3 arcsec FWHM1 FWHM size of cluster in arcsec 77 A1 --- --- [/] 78- 80 F3.1 pc FWHM2 FWHM size of cluster in parsecs 82- 85 F4.2 --- eta Best fitting parameter η (2) 87- 88 I2 --- Tb [2/10] Number of the table containing the individual photometry
Note (1): References as follows: a = Mendez et al. (2002AJ....124..213M) b = Thim et al. (2003ApJ...590..256T) c = Carignan (1985ApJS...58..107C) d = Grocholski et al. (2008ApJ...686L..79G) e = Tosi et al. (2001AJ....122.1271T) Note (2): η is the parameter that determines how steeply the envelope falls off at large radii.
Byte-by-byte Description of file: table[4-9].dat table10.dat
Bytes Format Units Label Explanations
1- 5 I5 --- Seq Allframe sequential number within the cluster 7- 12 F6.2 pix Xpos X coordinate on CCD image 14- 19 F6.2 pix Ypos Y coordinate on CCD image 21- 26 F6.3 arcsec oRA Offset in right ascension relative to cluster centre 28- 33 F6.3 arcsec oDE Offset in Declination relative to cluster centre 35- 41 F7.3 mag F435W ?=99.999 F435W absolute magnitude (1) 43- 49 F7.3 mag F555W F555W absolute magnitude 51- 57 F7.3 mag F814W F814W absolute magnitude 59- 64 F6.3 mag e_F435W ?=99.999 Error on F435W magnitude (1) 66- 71 F6.3 mag e_F555W Error on F555W magnitude 73- 78 F6.3 mag e_F814W Error on F814W magnitude
Note (1): A value of 99.999 indicates that no photometry is available in F435W
Acknowledgements: Soeren Larsen, s.s.larsen(at)
(End) S. Larsen [Astronomical Inst., Utrecht], P. Vannier [CDS] 28-Jun-2011
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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