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With the rapid progress in metallicity gradient studies at high-redshift, itis imperative that we thoroughly understand the systematics in thesemeasurements. This work investigates how the [NII]/Halpha ratio basedmetallicity gradients change with angular resolution, signal-to-noise (S/N),and annular binning parameters. Two approaches are used: 1. We downgrade thehigh angular resolution integral-field data of a gravitationally lensed galaxyand re-derive the metallicity gradients at different angular resolution; 2. Wesimulate high-redshift integral field spectroscopy (IFS) observations underdifferent angular resolution and S/N conditions using a local galaxy with aknown gradient. We find that the measured metallicity gradient changessystematically with angular resolution and annular binning. Seeing-limitedobservations produce significantly flatter gradients than higher angularresolution observations. There is a critical angular resolution limit beyondwhich the measured metallicity gradient is substantially different to theintrinsic gradient. This critical angular resolution depends on the intrinsicgradient of the galaxy and is < 0.02 arcsec for our simulated galaxy. We showthat seeing-limited high-redshift metallicity gradients are likely to bestrongly affected by resolution-driven gradient flattening. Annular binningwith a small number of annuli produces a more flattened gradient than theintrinsic gradient due to weak line smearing. For 3-annuli bins, a minimum S/Nof ~ 5 on the [NII] line is required for the faintest annulus to constrain thegradients with meaningful errors.

Systematics in Metallicity Gradient Measurements I : Angular Resolution, Signal-to-Noise and Annuli Binning