Getting ready for ultra-wide spectral scans: Reflections on the ALCHEMI Large Program

For decades we have been limited by sensitivity, bandwidth or a combination of both in order to cover very large spectral windows. ALMA just made it possible and it is about to multiply its speed to make it a routine. I would like to share the experience from more than two decades working on spectral line surveys and in particular some reflections from the ALCHEMI Large Program experience. ALCHEMI stands for the ALMA Comprehensive High-resolution Extragalactic Molecular Inventory, and it is the culmination of line surveys covering ALMA Bands 3 through 7 towards one of the nearest and most prolific extragalactic molecular emitters. Both the tools we currently use and even our own mindset may still be shaped by the limited data we had up until ALMA opened its eyes, and may be simply futile to deal with the datasets to come with WSU. I will present some of the ALCHEMI results and my own reflections on the journey of this fantastic dataset to publication.