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:
  5059.97803 -0.321999997
  5307.79883 -0.614600003
  5443.58203 -0.523699999
  5551.021 -0.674499989
  5665.11621 -0.693400025
  5785.53076 -0.242500007
  5872.9668 -0.506299973
  5943.37695 -0.691900015
  6010.17822 -0.698000014
  6078.64697 -0.654500008
  6139.24121 -0.5722
  6190.88086 -0.529299974
  6236.56104 -0.541100025
  6284.60986 -0.495700002
  6328.46924 -0.452300012
  6369.02979 -0.505500019
  6409.64307 -0.503700018
  6450. -0.570900023
  6490.47021 -0.516700029
  6531.18018 -0.50120002
  6571.39697 -0.576699972
  6611.88916 -0.457599998
  6652.5 -0.520200014
  6692.85498 -0.593999982
  6735.93604 -0.699100018
  6784.06299 -0.848800004
  6830.38281 -0.890999973
  6881.45801 -0.765299976
  6933.18311 -0.824199975
  6976.58789 -0.814100027
  7017.25195 -0.931800008
  7057.71582 -0.694199979
  7098.24219 -0.668200016
  7134.12305 -0.754400015
  7168.72119 -0.783299983
  7201.88281 -0.790899992
  7236.45215 -0.789699972
  7268.93408 -0.630900025
  7304.04102 -0.796400011
  7336.32812 -0.851599991
  7371.35107 -0.771200001
  7403.62207 -0.724399984
  7440.93408 -0.859799981
  7485.49414 -1.06459999
  7535.91211 -0.941299975
  7601.89209 -0.378500015
  7677.47607 -0.513800025
  7718.97412 -0.600899994
  7759.396 -0.372399986
  7800.24707 -0.316399992
  7840.19287 -0.635299981
  7880.55713 -0.703400016
  7921.25195 -0.819100022
  7964.03418 -1.08669996
  8014.63721 -1.26460004
  8071.93018 -1.64049995
  8142.48584 -2.23709989
  8228.45117 -1.31570005
  8308.00586 -0.528199971
  8365.25293 -0.532299995
  8403.70215 -0.406500012
  8433.99609 -0.356099993
  8460.8584 -0.448799998
  8485.92578 -0.352400005
  8503.93848 -0.475199997
  8526.44824 -0.32980001
  8544.4209 -0.399800003
  8561.90039 -0.487100005
  8575.40039 -0.307700008
  8588.90039 -0.269800007
  8602.40039 -0.550999999
  8615.90039 -0.535700023
  8629.40039 -0.356599987
  8642.90039 -0.618399978
  8656.40039 -0.504100025
  8669.90039 -0.399699986
  8683.40039 -0.52759999
  8701.59082 -0.371199995
  8719.58398 -0.424199998
  8742.04492 -0.473500013
  8760.00781 -0.460299999
  8782.46191 -0.410100013
  8805.19043 -0.362399995
  8832.42969 -0.505200028
  8859.49707 -0.3935
  8886.44531 -0.188600004
  8913.34473 -0.191
  8942.47461 -0.365799993
  8979.93066 -0.462900013
  9020.95801 -0.465499997
  9064.57031 -0.360199988
  9111.64648 -0.687300026
  9160.51758 -0.461699992
  9203.87305 -0.4366
  9243.96582 -0.432399988
  9286.29004 -0.580799997
  9346.90137 -0.524600029
  9423.75391 -0.614099979
  9509.68848 -0.408100009
  9600.93262 -0.486499995
  9699.29297 -0.712400019
  9803.44727 -0.586099982
  9921.70508 -1.18079996
  10059.1826 -1.18369997