The largest compilation of GC candidates in the vicinity of the M81/M82/NGC3077 triplet with J-PLUS

ANA CHIES SANTOS; JUAN PABLO CASO; RAFAEL DA SILVA DE SOUZA; ANA ENNIS; LUIS DÍAZ-GARCÍA

El Evento se desarrolló en forma virtual

Congreso; European Astronomical Society Anual Meeting 2021; 2021

European Astronomical Society

Extragalactic globular cluster (GC) system studies are generally focused on E/S0 galaxies not only because of their large number of clusters but mainly due to their easier detectability against the smooth background of their host galaxies. Models for GC formation predict that spiral galaxies (where GCs are generally less studied) should have a broad range in GC ages, which is yet to be confirmed observationally. To increase the statistics of known GCs around spiral galaxies, we search for GC candidates around the M81/M82/NGC3077 triplet with imaging from the Javalambre Photometric Local Universe Survey (J-PLUS) DR2. J-PLUS provides wide field-of-view images in 12 narrow, intermediate and broad-band filters optimized for stellar photometry. We first perform a tailored galaxy subtraction, DAOPHOT photometry and cross-match with confirmed GCs from literature to build an initial catalog with the 12-bands J-PLUS photometry. Then we employ a customized statistical model to search for new GC candidates based on their proximity, via propensity score matching, to the list of known GCs in a low-dimensional PCA projection of the multi-dimensional J-PLUS photometric parameter space. The model properly accounts for missing data, and photometric errors. A search in a region of ~3.1 square degrees with HI emission encompassing the M81/M82/NGC3077 triplet expands the current list of known GCs by at least 2.5 folds. This study provides a testbed of what can be done with the upcoming wide-field space surveys at much greater distances.