Linked scan at constant B(1-(E/E0))1/2/E: Difference between revisions
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|A linked scan at constant B[1-(E/E<sub>0</sub>)]<sup>1/2</sup>/E may be performed on a [[sector instrument]] that incorporates at least one [[electric sector]] plus one [[magnetic sector]]. It involves holding the [[accelerating voltage]] fixed and scanning the magnetic field (B) and electric field (E) simultaneously, so as to maintain the quantity B[1-(E/E<sub>0</sub>)]<sup>1/2</sup>/E at a constant value. This constant value is equal to B<sub>3</sub>/E<sub>0</sub> , where E<sub>0</sub> and B<sub>3</sub> are, respectively, the electric sector field and magnetic sector field required to transmit m<sub>3</sub> ions in the main ion beam; m<sub>3</sub> represents the mass (m<sub>1</sub>-m<sub>2</sub>) of the selected neutral fragment whose precursor (parent) ion spectrum is required. The fragmentation reactions so observed occurred in a field-free region traversed before the two sectors scanned in this way. This term should not be used without prior explanation of the meanings of B, E and E<sub>0</sub>. | |A linked scan at constant B[1-(E/E<sub>0</sub>)]<sup>1/2</sup>/E may be performed on a [[sector instrument]] that incorporates at least one [[electric sector]] plus one [[magnetic sector]]. It involves holding the [[accelerating voltage]] fixed and scanning the magnetic field (B) and electric field (E) simultaneously, so as to maintain the quantity B[1-(E/E<sub>0</sub>)]<sup>1/2</sup>/E at a constant value. This constant value is equal to B<sub>3</sub>/E<sub>0</sub> , where E<sub>0</sub> and B<sub>3</sub> are, respectively, the electric sector field and magnetic sector field required to transmit m<sub>3</sub> ions in the main ion beam; m<sub>3</sub> represents the mass (m<sub>1</sub>-m<sub>2</sub>) of the selected neutral fragment whose precursor (parent) ion spectrum is required. The fragmentation reactions so observed occurred in a field-free region traversed before the two sectors scanned in this way. This term should not be used without prior explanation of the meanings of B, E and E<sub>0</sub>. | ||
The term "B[1-(E/E0)]1/2/E linked scan" is not recommended. | The term "B[1-(E/E0)]1/2/E linked scan" is not recommended. | ||
The above definitions are merely examples of the types of linked scan that might be used. Other linked scans can readily be defined in a similar manner. | |||
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Revision as of 00:17, 4 March 2005
| DRAFT DEFINITION |
| Linked scan at constant B(1-(E/E0))1/2/E |
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| Related Term(s): |
| Reference(s): |
| This is an unofficial draft definition presented for information and comment. |
Orange Book Entry
This can be performed with a sector instrument incorporating at least one electric sector plus one magnetic sector. The magnetic sector field strength, B, and the electric sector field strength, E, are scanned simultaneously, while holding the accelerating voltage , V, constant, so as to maintain the ratio B [1- (E /E 0)]1/2 /E constant. This constant value is equal to B3/E0, where E0 and B3 are respectively the electric and magnetic sector fields required to transmit M3+ ions in the main ion beam; m3 represents the mass (m1-m2) of the selected neutral fragment M3 whose precursor spectrum is required. The fragmentation reactions thus observed occur in a field-free region traversed before the two sectors scanned in this way. The term 'B [1- (E /E 0)]1/2/E linked scan????????????????????????? is not recommended.
