Substellar regime of Initial Mass Function (IMF) and the formation process of brown dwarfs and planetary-mass objects are still open issues. Since they are relatively bright at younger ages, NIR surveys at nearby SFRs are efficient to detect them. The JHK photometric survey (K lim∼20) in NGC2068/71 have identified hundreds of very low-mass YSO candidates from the NIR colors. The number ratios of Class I/II, TTS/BD and their substellar MFs in NGC2068/71 differ each other. NGC2068 which includes two B-type stars appears to be a “BD-rich" cluster, while NGC2071 appears to be a “TTS-rich" cluster. From these results, formations of very low-mass objects in NGC2068/71 seems to depend on the local environments. Only from NIR photometry, however, there are some uncertainties of the derived mass on the age assumption of 1 Myr and extragalactic contaminations. Subaru/MOIRCS NIR multi-object spectroscopy can confirm them as substellar YSOs by their temperature from the depth of water absorption and their luminosities using evolutionary models. This observation could reveal statistically significant MFs down to the BD regime for spectroscopically confirmed YSOs and whether the formation of VLMOs depends on the presence of B stars and/or the cloud properties.
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