We have been carrying out UKIRT and Subaru JHK photometric surveys in various (low - massive) nearby SFRs to search for brown dwarfs (BDs) and planetary mass objects (PMOs), and their IMFs. The JHK photometry (K lim∼19) of R CrA, Lupus I and L1689/1709 which are located in ρ Oph cloud complex, have been identified hundreds of very low-mass YSO candidates from the NIR colors. As a result, we found that their IMF increased from TTS down to the completeness limit (PMO), through a local peak in the BD regime, while spectroscopic MF derived in ρ Oph which have a peak in 0.12M⊙ (Alves de Oliveira et al. 2014) . In addition, TTSs and BDs in L1689/1709 are located in the higher dust density regions like R CrA and Lupus I. It suggests that substellar IMFs and their formation might be depended on the local envioronments. 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 multi-object spectroscopy can confirm that they are substellar YSOs. This observation could reveal spectroscopically confirmed MFs down to the PMO regime and whether the formation of BDs/PMOs depends on the cloud properties.
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