PAPAS: determine the actual SFR in red spirals falling into clusters

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Not all red galaxies in clusters are red and dead. In unrelaxed clusters - like Virgo – also red spirals exist that show ongoing star formation, reddened by dust. We aim to find out whether the dusty red spirals are common field galaxies in the process of entering the cluster potential or whether their star formation is triggered by ram pressure from moving across the inter-cluster medium. In our best studied cluster, Abell 901/2 the determination of the SFR from H and the UV+FIR flux leads to conflicting results. The PAnic Paschen Alpha Survey (PAPAS) is proposed to check the H-based SFR in several intermediate redshift galaxy clusters by using the Paschen-line red-shifted into the K-band. The current proposal should complete the observations of A226/8 by repeating observations lost due to bad weather in H2016.