hetgcal> @meas_line_angle  

 HEG   15.010 A line,  acisf1099_000N001_evt1.fits

  Plus-side:       2688.91     -247.836
 Minus-side:      -2687.82      244.779
      Angle:      -5.23482

hetgcal> @meas_line_angle

 MEG   15.010 A line,  acisf1099_000N001_evt1.fits

  Plus-side:       1345.40      109.378
 Minus-side:      -1344.70     -112.955
      Angle:       4.72468