[spctools-discuss] How does X!tandem handle the precursor charge in low resolution data

Hello: I collected some data from LTQ XP and converted them to mzXML by ReAdw. I noticed there is no precursor charge information, unlike the data from LTQ Orbitrap. Nevertheless, it seems X!tandem can still get it right. So i become very curious how it handles the charge. Does anyone know?

Re: [spctools-discuss] How does X!tandem handle the precursor charge in low resolution data

When a precursor charge is not known, the logic that is used to analyze the data is as follows. If there are no peaks above the precursor m/z then the spectrum is assumed to be 1+ and analyzed as such. If there are peaks above the precursor m/z then the precursor ion is assumed to be multiply