sourceArn

This parameter is used only for sending authorization. It is the ARN of the identity that is associated with the sending authorization policy that permits you to send for the email address specified in the Source parameter.

For example, if the owner of example.com (which has ARN arn:aws:ses:us-east-1:123456789012:identity/example.com) attaches a policy to it that authorizes you to send from user@example.com, then you would specify the SourceArn to be arn:aws:ses:us-east-1:123456789012:identity/example.com, and the Source to be user@example.com.

For more information about sending authorization, see the Amazon SES Developer Guide.