# # Program information file # PROGRAM_ID 2022A080 PROGRAM_TITLE Calibrating Brackett alpha as a protostellar mass accretion tracer PROGRAM_INV1 Jonathan Williams PROGRAM_INV2 Christian Flores PROGRAM_INV3 Antonella Natta PROGRAM_INV4 Carlo Manara PROGRAM_INV5 Maria Koutoulaki PROGRAM_SCICAT stellar PROGRAM_ABSTRACT_BEG We propose to use SpeX to observe the Brackett alpha and gamma lines at R=1500 in a sample of pre-main sequence [Class II] and protostellar [Class I] sources in Ophiuchus. The observations of the Class II sample will allow us to calibrate the relationship between Br alpha luminosity and accretion luminosity. We will then apply this to determine the accretion rates in the younger, more embedded Class I sources to study this relatively poorly explored phase of high stellar growth. PROGRAM_ABSTRACT_END