I have not corrected for the heliocentric redshift in these data.

**************************************************
Perr must stand for photon noise error.
I assume no reddening correction either

NGC 628 = M74
heliocentric velocity
from lines in sn spectra  +631 km/s  iauc 7822 S. Smartt & P. Meikle
from Leda  in radio       +656 km/s
from Leda  in optical     +639 km/s
from Leda  mean           +656 km/s

Foreground extinction in
B from Leda/Schlegel   0.30
E(B-V)=.30/4           0.075
E(B-V)=.30/4.1         0.073  See Cardelli p. 249
Paolo E(B-V)           0.08


**********************************************

Polarization  2002 feb 8

lambda(A), q(%), u(%), P(%), theta(deg), Perr.

END:
  5121.86377  0.0152000003
  5402.63281 -0.220100001
  5569.5 -0.142100006
  5744.99316  0.0276999995
  5884.21289 -0.224900007
  5983.55518 -0.350100011
  6079.13916 -0.153200001
  6167.88477 -0.25029999
  6240.07715 -0.230800003
  6307.79883 -0.2095
  6375.1748 -0.214699998
  6442.53906 -0.207499996
  6510.11523 -0.347299993
  6577.08105 -0.226300001
  6644.73877  0.0105999997
  6711.979 -0.0644000024
  6779.68799 -0.188700005
  6852.43604 -0.00760000013
  6929.81689 -0.0785999969
  6996.14795  0.0344999991
  7056.90283 -0.0465000011
  7110.95801 -0.131999999
  7164.8252 -0.119400002
  7219.06494 -0.0966000035
  7265.9751 -0.0405000001
  7306.38623  0.0828000009
  7346.68115 -0.313800007
  7393.36084  0.0219000001
  7453.45117 -0.249899998
  7527.29492  0.0725999996
  7638.97314 -0.310799986
  7718.26416 -0.356900007
  7772.17822 -0.309399992
  7826.00098 -0.449900001
  7879.68604 -0.26789999
  7940.12012 -0.218600005
  8013.5918 -0.203500003
  8106.47412  0.147300005
  8225.24023  0.358399987
  8329.55469 -0.164399996
  8394.82129 -0.119400002
  8441.2168 -0.234699994
  8481.52344 -0.325700015
  8514.94727 -0.220599994
  8541.8584 -0.395399988
  8568.7998 -0.25909999
  8595.65039 -0.216999993
  8622.61523 -0.258399993
  8649.5752 -0.266499996
  8676.56543 -0.25150001
  8703.53418 -0.142100006
  8730.45215 -0.220400006
  8757.42188 -0.122199997
  8790.76367 -0.231800005
  8831.62988 -0.242300004
  8872.14453 -0.301699996
  8912.52734 -0.278600007
  8959.26172 -0.414099991
  9013.99805 -0.176499993