Reaching the End of the White Dwarf Cooling Sequence in NGC 6791

Understand

We present new observations of the white dwarf sequence of the old open cluster NGC 6791.

• The brighter peak previously observed in the white dwarf luminosity function (WDLF) is now better delineated, and the second, fainter peak that we suggested earlier is now confirmed.
• A careful study suggests that we have reached the end of the white dwarf sequence.
• The WDs that create the two peaks in the WDLF show a significant turn to the blue in the color-magnitude diagram.