In this paper we present a study and comparison of the star formation rates ( SFR ) in the fields around NGC 1898 and NGC 2154 , two intermediate-age star clusters located in very different regions of the Large Magellanic Cloud .
We also present a photometric study of NGC 1898 , and of seven minor clusters which happen to fall in the field of NGC 1898 , for which basic parameters were so far unknown .
We do not focus on NGC 2154 , because this cluster was already investigated in Baume et al .
2007 , using the same theoretical tools .
The ages of the clusters were derived by means of the isochrone fitting method on their clean color-magnitude diagrams .
Two distinct populations of clusters were found : one cluster ( NGC 2154 ) has a mean age of 1.7 Gyr , with indication of extended star formation over roughly a 1 Gyr period , while all the others have ages between 100 and 200 Myr .
The SFRs of the adjacent fields were inferred using the downhill-simplex algorithm .
Both SFRs show enhancements at 200 , 400 , 800 Myr , and at 1 , 6 , and 8 Gyr .
These bursts in the SFR are probably the result of dynamical interactions between the Magellanic Clouds ( MCs ) , and of the MCs with the Milky Way .