Program: GN-2020B-Q-129

Exploring the low-mass end of the initial mass function (IMF) helps understand how planetary-mass objects form. Can cloud fragmentation processes occuring in star forming regions (SFR) produce objects down to a Jupiter mass? Does a cut-off exist at very low masses? Is there a mass overlap with other processes such as core accretion or disk instability occuring for exoplanet formation. We conducted a 25 sq. deg. photometric survey at CFHT to isolate planetary-mass objects down to 3 Jupiter masses in the nearby Taurus star-forming region. This survey uses a novel technique: a water band filter coupled with regular J and H bands that is sensitive to the broad water vapor absorption band at 1.45 microns present in the late M, L, T and Y spectral types. In semester 17A, we started spectroscopic follow-up at Gemini, Palomar and IRTF and demonstrated a good success rate (80%) at identifying substellar objects. We already doubled the number of known L-type objects in Taurus, a result that exceeds predictions from an IMF having a traditional log-normal distribution. To help weed out false positives, not only do we incorporate PANSTARRS, WISE and UKIDSS photometry and images in our selection constraints, but we also performed proper motion measurements to calculate membership probabilities. This Gemini proposal is to continue the spectroscopic follow-up of 7 candidates in Band 1/2.