Prepared by running tfcoh (many times), multiplicate.py,
max_coherences.py, and veto_max.py.

Black is H1-H2 coherence, blue is the maximum (per bin) across all
H1-PEM*H2-PEM products.  The black horizontal line is the 1/Tchunks line
of the H1-H2 coherence.  Note that Tchunks of H1-H2 coherence is
different than that of the H[12]-PEM coherences.  H[12]-PEM coherences
were computed by Sarah Vigeland of Carleton College.  I computer H1-H2
coherence with rather different parameters and data quality cuts.

Output of veto_max.py:
Threshold: 3.162278e-06  ==  10^(-5.50)
1/Tchunks: 9.105727e-06  ==  10^(-5.04)
% of total frequency bins lost: 0.2709
% of [50,350]Hz bins lost: 0.5126