  We present high spatial resolution observations of chromospheric evaporation
in the flare SOL2014-03-29T17:48. Interface Region Imaging Spectrograph (IRIS)
observations of the FeXXI 1354.1 A line indicate evaporating plasma at a
temperature of 10 MK along the flare ribbon during the flare peak and several
minutes into the decay phase with upflow velocities between 30 km s$^{-1}$ and
200 km s$^{-1}$. Hard X-ray (HXR) footpoints were observed by RHESSI for two
minutes during the peak of the flare. Their locations coincided with the
locations of the upflows in parts of the southern flare ribbon but the HXR
footpoint source preceded the observation of upflows in FeXXI by 30-75 seconds.
However, in other parts of the southern ribbon and in the northern ribbon the
observed upflows were not coincident with a HXR source in time nor space, most
prominently during the decay phase. In this case evaporation is likely caused
by energy input via a conductive flux that is established between the hot (25
MK) coronal source, which is present during the whole observed time-interval,
and the chromosphere. The presented observations suggest that conduction may
drive evaporation not only during the decay phase but also during the flare
peak. Electron beam heating may only play a role in driving evaporation during
the initial phases of the flare.
