J/MNRAS/492/993 Super star clusters of M82's disk (Cuevas-Otahola+, 2020) ================================================================================ Structural analysis of disc super star clusters of M82: size and profile shape at intermediate ages. Cuevas-Otahola B., Mayya Y.D., Puerari I., Rosa-Gonzalez D. =2020MNRAS.492..993C (SIMBAD/NED BibCode) ================================================================================ ADC_Keywords: Clusters, globular ; Optical Keywords: catalogues - (Galaxy:) globular clusters: general - galaxies: clusters: general Abstract: We present the structural parameters of 99 super star clusters (SSCs) in the disc of M82. Moffat-EFF, King, and Wilson models were fitted using a {chi}^2^-minimization method to background-subtracted surface brightness profiles in the F435W (B), F555W (V), and F814W (I) bands of the Advanced Camera for Surveys (ACS) of the Hubble Space Telescope. The majority of the SSC profiles are best fitted by the Moffat-EFF profile. The scale parameter r_d_ and the shape parameter {gamma} in the three filters are identical within the measurement errors. The analysed sample is big enough to allow the characterization of the distributions of core radii R_c_ and {gamma}. The obtained distribution of R_c_ follows a lognormal form, with centre and {sigma}log(R_c_/pc) being 1.73pc and 0.25, respectively. The {gamma} distribution is also lognormal with centre and {sigma}log({gamma}) being 2.88 and 0.08, respectively. M82 is well known for the absence of current star formation in its disc, with all disc SSCs older than 50Myr and hardly any cluster older than ~300Myr. The derived distributions compare very well with the distributions for intermediate-age clusters in the Large Magellanic Cloud (LMC), which is also a low-mass late-type galaxy similar to M82. On the other hand, the distributions of R_c_ in both these galaxies are shifted towards larger values as compared to SSCs of similar age in the giant spiral galaxy M83. M82 and LMC also span a narrower range of {gamma} values as compared to that in M83. Description: The sample of super star clusters (SSCs) for structural analysis was selected from the catalogue of M82 disc SSCs from Mayya et al. (2008ApJ...679..404M, Cat. J/ApJ/679/404), which consists of 393 objects, and is based on the detection of SSCs in the F435W (B), F555W (V), and F814W (I) bands of the HST/ACS. We used the same images that were used for cluster detection to extract SBPs. These images were part of the HST Legacy Survey, which were made available in reduced form by the Hubble Heritage Team (Mutchler et al. 2007PASP..119....1M). The image scale corresponds to 0.05arcsec/pixel and covers the entire optical extent of M82. Exposure times were 1600, 1360, and 1360s in filters B, V, and I, respectively. The zero-point magnitudes in the Vega system were extracted from Sirianni et al. (2005PASP..117.1049S), with values 25.779, 25.724, and 25.501 for the B, V, and I bands, respectively. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file table1.dat 41 393 Fitting radius and background value for all M82 disc SSCs tablea1.dat 14 99 Geometrical properties of M82 disc SSCs -------------------------------------------------------------------------------- Byte-by-byte Description of file: table1.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 4 A4 --- ID Object identifier from Mayya et al. (2008ApJ...679..404M, Cat. J/ApJ/679/404) (DNNN) 6- 14 F9.5 deg RAdeg Right ascension (J2000) 16- 23 F8.5 deg DEdeg Declination (J2000) 25- 26 I2 pix Rip Innermost inflexion point R_ip_ 28- 30 I3 pix R3s ?=-99 Radius at which the cluster surface brightness is equal to 3 times the background noise {sigma}_bg_ 32- 36 F5.2 mag/arcsec2 mubg Background surface brightness 38- 41 F4.2 mag/arcsec2 e_mubg Error on mubg -------------------------------------------------------------------------------- Byte-by-byte Description of file: tablea1.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 4 A4 --- ID Object identifier from Mayya et al. (2008ApJ...679..404M, Cat. J/ApJ/679/404) (DNNN) 6- 9 F4.2 --- Ell Ellipticity 11- 14 I4 deg PA [] Position angle -------------------------------------------------------------------------------- History: From electronic version of the journal ================================================================================ (End) Ana Fiallos [CDS] 13-Mar-2023