Info

This is a visualization of the ACT DR5 maps. Pan and scroll using the mouse, like on google maps. Use the keyboard to change what is shown.

• Press f/r to switch between f090, f150, f220.
• Press c/v to cycle through T, Q, U, E, B, F.
• Press s to toggle source subtraction on/off.
• Press j/k to switch between act+planck, and and planck.
• Press d to switch between day+night and night only.
• Press n/m to switch between maps using data up to 2019, 2018 and 2016 (DR4).
• Press g to switch between color and gray-scale. Gray-scale is better for looking at low-S/N features, like point sources and clusters in the F map, or polarization.
• Press u/i to increase/decrease the color scale in steps of 10%.
• Press o/p to shift the color scale center.
• Press q to toggle the coordinate grid.

If no keyboard is available you can click the hamburger icon in the top right corner to add buttons for inputting these keys to the top of the screen.

You can select a region by holding down the control key while dragging with the mouse. The region will be outlined in a dashed magenta rectangle. Pressing the enter key will download a fits file corresponding to this region. Press escape to dismiss the region again. The downloaded file will contain all three of T, Q and U regardless of which Stokes field is currently visible.

The act-only maps are gently filtered to reduce ground pickup. This was done by subtracting a constrained noise realisation from each 8x8 degree tile (the tiles are 4x4 degrees, but have a 2 degree padding on each side), where the realisation is constrained by a 1 degree thick region around the edge of the exposed part of the tile. This can be expected to remove signal on 5-10 degree scales or longer.

F is an approximately matched filtered map meant to maximize point source S/N. It is not optimal and is is meant only for visual inspection.

Datasets

• s13-s16: mr3f with gain corrections from Steve and beams from Marius. They day gains and beams were calibrated to the night-data using cross-correlation.
• s17: s17v5 with gain, beams and day as above.
• s18: s18v1 night was calibrated from s17 night, and then used to calibrate s18 day. Then both were calibrated vs. Planck.