  EUSO-TA is a ground-based florescence detector built to validate the design
of an ultra-high energy cosmic ray fluorescence detector to be operated in
space. EUSO-TA detected the first air shower events with the technology
developed within the JEM-EUSO program. It operates at the Telescope Array (TA)
site in Utah, USA. With the external trigger provided by the Black Rock Mesa
fluorescence detectors of Telescope Array (TA-FDs), EUSO-TA observed nine
ultra-high energy cosmic ray events and several laser events from the Central
Laser Facility of Telescope Array and portable lasers like the JEM-EUSO Global
Light System prototype. The reconstruction parameters of the cosmic ray events
which crossed the EUSO-TA field of view (both detected and not detected by
EUSO-TA), were provided by the Telescope Array Collaboration. As the TA-FDs
have a wider field of view than EUSO-TA ($\sim$30 times larger), they allow the
cosmic ray energy reconstruction based on the observation of most of the
extensive air-shower profiles, including the shower maximum, while EUSO-TA only
observes a portion of the showers, usually far from the maximum. For this
reason, the energy of the cosmic rays corresponding to the EUSO-TA signals
appear lower than the actual ones. In this contribution, the analysis of the
cosmic-ray events detected with EUSO-TA is discussed.
