NGC 2580 and NGC 2588*,**
Two open clusters in the Third Galactic Quadrant
1
Dipartimento di Astronomia, Università di Padova, Vicolo Osservatorio 2, 35122 Padova, Italy
2
Facultad de Ciencias Astronómicas y Geofísicas de la UNLP, IALP-CONICET, Paseo del Bosque s/n, La Plata, Argentina
3
CAAUL, Observatório Astronómico de Lisboa, Tapada da Ajuda, 1349-018 Lisboa, Portugal
Corresponding author: G. Baume, baume@pd.astro.it
Received:
2
October
2003
Accepted:
21
December
2003
We present CCD broad band photometric observations in the fields of the Third Galactic Quadrant open clusters NGC 2580 and NGC 2588 (V(I)C and UBV(RI)C respectively). From the
analysis of our data we found that NGC 2580 is located at a distance of about 4 kpc and its age is close to 160 Myr. As for NGC 2588, it is placed at about 5 kpc from the Sun and is 450 Myr old. This means that NGC 2588 belongs to the extension of the Perseus arm, whereas NGC 2580 is closer to the local arm structure. The luminosity functions (LFs) have been constructed for both clusters down to 
together with their initial mass functions (IMFs) for stars with masses above 
–1.5 
. The IMF slopes for the most massive bins yielded values of 
for NGC 2580 and 
for NGC 2588. In the case of this latter cluster we found evidence of
a core-corona structure produced probably by dynamical effect. In the main sequences of both clusters we detected gaps, which we suggest could be real features.
Key words: Galaxy: open clusters and associations: individual: NGC 2580, NGC 2588 / Galaxy: open clusters and associations: general
© ESO, 2004