by Jing Wang (CASS)

This figure, taken from Cormier et al. (2016) , shows the optical image, CO image and CO spectrum for 2 of the HI-rich galaxies from the Bluedisk project . In total Cormier et al. have obtained CO images for 27 Bluedisk galaxies with the IRAM 30-m telescope.They compared the CO related properties between HI-rich and control galaxies , searching for signs of gas accretion. Surprisingly they find that HI-rich galaxies have similar H ₂ masses as the control galaxies; and the HI-rich galaxies actually have smaller H ₂ disks (normalised by R ₂₅ ) compared to the control galaxies. The on-going gas accretion hence has not led to an appreciable growth of the CO discs in the sample.

Reference: D. Cormier, F. Bigiel, J. Wang, J. Pety, A. Usero, S. Roychowdhury, D. Carton, J. M. van der Hulst, G. I. G. Jozsa, M. Gonzales Garcia, A. Saintonge 2016, MNRAS, in press