spectrum, minimum parent m+h

Syntax

The value for this parameter is a positive floating point number M_min > 0.

Notes

1. No error is generated for inappropriate values entered in this parameter.
2. If this parameter is absent, a default value of 850 is used.
3. In most experimental situations, a value of 500 is recommended.
4. This parameter is not used if the value of spectrum, use noise suppression = no.

Description

This parameter is used to supress the analysis of spectra that were generated by low mass parent ions. Depending on the instrumentation and excitation energy used to generate fragment ions, there will be some low mass cutoff value, below which there is very little chance of generating an interpretable MS/MS spectrum. In many experimental conditions, there will also be noise peaks in the parent ion spectrum, generated by the ion source and chemical noise. The value selected for M_min is used to reject these spectra.