The MODIFY VELOCITY command
Keywords: class-spectral-axis-v12

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The `MODIFY VELOCITY` command

This command is used to assign a new source systemic velocity to the current spectrum. This command is used when the line rest frequency is known very accurately but the line appears shifted. This implies that the source systemic velocity is slightly offset (see Section ).

Subsections

- Principle
- The signal frequency axis
- The image frequency axis
- The doppler factor