Bence Albee α-factor table calculated from the PAP procedure

1. Introduction

Bence-Albee alfa-factor (constant type) tables in this page were calculated from the PAP procedure (Pouchou & Pichoir, 1991) for conditions at 15, 20 and 25kV accelerating voltage and 40 degrees take-off angle. Details of calculation procedure are described in Kato (2005).

2. References

When you publish a paper including analysis result using this table, please include following papers:

• Bence, A.E. and Albee, A.L. (1968) Empirical correction factors for the electron microanalysis of silicate and oxides. Journal of Geology, 76, 382-403.
• Kato, T. (2005) New accurate Bence-Albee α-factors for oxides and silicates calculated from the PAP correction procedure, Geostandards and Geoanalytical Research, 29, 83 - 94.

Example

The Bence and Albee (1968) method was employed for matrix corrections using the α-factor table by Kato (2005).

3. Revision history

1.01

Initial version.

4. Download

Copyright KATO Takenori, 2003-2005. All rights reserved.

Alpha-factor tables are covered by the GSD general license term.

Revision 1.01

• KatoPAP.15: 15 keV, 40 degree
• KatoPAP.20: 20 keV, 40 degree
• KatoPAP.25: 25 keV, 40 degree

5. Installation to JEOL JXA-8800R (NO WARRANTY!)

This instruction assumes the program version 2.10 on the HP-9000/HP-UX 9 system. Please note that the Bence-Albee program is an optional software. If your system does not have the license for the Bence-Albee correction program, please contact with JEOL to purchase the license.

WARNING: Changing alpha-factor(s) on working system has potential to crash the system.

Setup the alpha-factor table files

Download above files and transfer them as

                /users/epma/phys/mac/KatoPAP.15
                /users/epma/phys/mac/KatoPAP.20
                /users/epma/phys/mac/KatoPAP.25

without change of the end-of-line code.

Edit configuration file of the Bence-Albee correction

The alpha-factor table used by the Bence-Albee mode is described in the file

as text format. The last two lines of this file might be:

          Alpha factor : Albee
          Alpha factor : Nakamura

This configuration means that alpha-factor of Albee and Ray (1970) overwritten by that of Nakamura and Kushiro (1970) is used. To change alpha-factor table chosen, these two lines should be commented out and one line should be added as:

          # Alpha factor : Albee
          # Alpha factor : Nakamura
          Alpha factor : KatoPAP

JEOL JXA-8100/8200 (courtesy of Dr. Hokada)

The directory for the alpha-factor table files is:

                /opt/epma/phys/mac/

and the configuration file to be edited is:

                /opt/epma/phys/ba.cnd

6. Q & A

1. What is benefit of this table.

• Certain EPMA systems support only (1) Bence-Albee method, (2) conventional ZAF model and (3) surface-centered Gaussian model modified by Armstrong (1991). Such system may cause serious errors in analysis of high-atomic-number elements, such as Pb, Th and U. This may causes errors in the CHIME dating.
• The alpha-factor tables were calculated using m.a.c.s after an updated version of Henke et al. (1993) dataset. This may solve problems from the MAC30 algorithm (Heinrich, 1987), such as overestimation of Mg in Fe.

2. This table causes low total problem.

Please check (1) surface conditions of specimens, (2) coating thickness, (3) focusing condition and (4) standard sets chosen. If you believe problem(s) in the table, please let me know of details.

3. High-total (102%) problem is not solved.

Please check the installation procedure.

4. Can I help you?

Yes. Please make this page more English.

The names of actual companies and products mentioned herein may be the trademarks of their respective owners.