  The Fermi Large Area Telescope (LAT) is the most sensitive instrument ever
deployed in space for observing gamma-ray emission >100 MeV. This sensitivity
has enabled the LAT to detect gamma-ray emission from the Sun during quiescent
periods from pions produced by cosmic-ray protons interacting in the solar
atmosphere and from cosmic-ray electrons interacting with solar optical
photons. The LAT has detected high-energy gamma-ray emission associated with
GOES M-class and X-class X-ray flares accompanied by coronal mass ejections and
solar energetic particle events. In a number of cases, LAT has detected gamma
rays with energies up to several hundreds of MeV during the impulsive phase and
gamma rays up to GeV energies sustained for several hours after the impulsive
phase. This presentation focuses on observations in the impulsive emission
phase in solar flares, including the modest GOES M2-class flare at
SOL2010-06-12T0057 and more recent detections, such as the bright X-class
flares of March 2012.
