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.

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.