Sistema de cúmulos globulares de la galaxia lenticular NGC 6861: en busca de indicios sobre la formación de las S0s (con referato)

CARLOS ESCUDERO; FAVIO R. FAIFER; LILIA P. BASSINO; JUAN PABLO CALDERÓN; JUAN PABLO CASO

Mar del Plata, Buenos Aires, Argentina

Congreso; 55 Reunión Anual de la Asociación Argentina de Astronomía; 2012

Asociación Argentina de Astronomía

We present a preliminar photometric study of the globular cluster system (GCS), associated to the lenticular galaxy (S0) NGC 6861, which is located in a low density environment (d?31.8 Mpc). It is based on GEMINI/GMOS images (GS-2010B-Q-2: PI Lilia P. Bassino) in the filters g´, r´, i´ of three fields, one of them centered in the galaxy. We find a large number of GCs candidates and detect the presence of at least two sub-populations of GCs (``blue´´/metal-poor and ``red´´/metal-rich). The spatial distribution of ``red´´ candidates presents a higher concentration toward the galaxy (associated to the bulge?), while the distribution of ``blue´´ candidates is more homogeneus over the three fields (associated to the halo?). In the color-magnitud diagram, the ``blue´´ GC candidates show a possible mass-luminosity relation, known as ``blue-tilt´´, probably detected for the first time in a lenticular galaxy.