GhostPeaks

Step-by-Step guide to setting up peakwidths for a 3D spectrum.

CARA offers two options for setting up peakwidths in 3D spectra.

1. You can set them up for each SpectrumType. e.g. HNCA. Every spectrum of this SpectrumType will take the default values for peakwidth from the SpectrumType.
2. You can customize the peakwidths for each spectrum.

Method 1.

1. Simply click on the SpectrumType in question in the CARA-explorer.
2. Expand the spectrumType.
3. Click on the Dimension.
4. Use the context menu to enter the peakwidth for the selected dimension.

Method 2.

1. Open the 3D spectrum with PolyScope2? (open PolyScope2? with the relevant HSQC and then select the 3D in the Strip Menu Select Spectrum).

   In our example, we open the HSQC15N, and then select the HNCA in the strip. First we determine the peakwidth along D1 (the HN dimension in an HNCA).

2. Click on a Peak in the Plane which is isolated and has nice resolved peaks in the 3D strip.
3. In the Strip, use Shift-Click-Drag to draw a box around a 3D peak... in the left strip (the HN/CA strip in our HNCA)

1. And note down the width and height of the peak (given in ppm next to the w and h respectively on the status line)
2. Right click in the left Strip, and select the context menu Set peakwidth
3. Enter the previously noted value in ppm (0.15).
4. Repeat the same procedure for the right strip to set the peakwidth along D3 (the N dimension in an HNCA).
5. Finally, to set the peakwidth along the strip dimension D2 (the CA dimension in an HNCA): Use the context menu Set peakdepth in the plane and enter the height of the peaks in the strips.

CARA should now display only crosspeak symbols when the peak intensity is visible.