New Multi-Collector Mass Spectrometry Data for Noble Gases AnalysisAlessandro Santato,1 Doug Hamilton,1 Jan Wijbrans,2 Claudia Bouman1

1Thermo Fisher Scientific, Bremen, Germany 2VU University Amsterdam, Faculty of Earth and Life Sciences, Amsterdam, The Netherlands

Overview Purpose: We test the performance of new high gain amplifiers equipped with 1013 Ω feedback resistors. The tests are carried out on the multi-collector Thermo Scientific™ HELIX MC Plus™ noble gas MS.

Methods: Circa 2.4 x 10-13 mole of argon was analyzed using three different multi-collector modes and 40Ar/36Ar and 38Ar/36Ar was measured.

Results: The new 1013 Ω amplifier show a decisive improvement in the measurement of small samples.

Introduction On the Earth, noble gases are present as rare elements and in most of the cases their concentration within samples is extremely low. Therefore their analysis requires a high detection efficiency which implies ultra high vacuum systems, mass spectrometers able to operate in static mode, and detectors capable of reading small signals. Here we present a comparison between the latest amplifiers equipped with 1013 Ω resistors and the established state-of-art Thermo Scientific detector technology, represented by: 1012 amplifiers and the latest electron multiplier: Compact Discrete Dynode™ (CDD).

Methods

Sample Preparation and Analysis

Argon from atmospheric air was prepared with the Thermo Scientific NG Prep System™ and used as standard sample for all the tests.

Circa 2.4 x 10-13 mol of argon were repeatedly analyzed using three different collector configurations.

Collector Configurations

Argon mass 40, 38 and 36 were analyzed using three different multi-collector modes, see figure 1.

40Ar and 38Ar were always analyzed, respectively: on a Faraday cup coupled with a 1011 Ω amplifier and on an electron multiplier CDD. The 36Ar was analyzed with three different detector configurations: a Faraday cup coupled with the 1012 Ω amplifier, an electron multiplier CDD and a Faraday cup coupled with the latest 1013 Ω amplifier.

Mass Spectrometry

The Thermo Scientific HELIX MC Plus multi-collector static vacuum mass spectrometer is the ultimate solution for noble gas analysis. Equipped with a high-resolution magnetic sector analyzer and with a variable multi collector array, which incorporates 5 Combined Faraday Multiplier (CFM) detectors, and is capable of analyzing up to five isotopes of neon, argon, krypton and xenon simultaneously, at new levels of resolution.

Data Analysis

Thermo Scientific Qtegra™ Intelligent Scientific Data Solution™ (ISDS) was used for data acquisition and control software. Plots were made using Microsoft™ Office Excel™ 2007.

Conclusion The higher sensitivity of the new amplifiers equipped

with a 1013 Ω feedback resistor represents a decisive improvement in small sample analysis.

In the 40Ar/36Ar measurement the new 1013 Ω amplifier is capable of achieving a relative standard error between 0.13 and 0.44%, which represents a significant progress if compared with 1012 Ω amplifier (relative standard error is between 0.41 and 1%).

The electron multiplier is the best detector in terms of sensitivity but its drift due to the variation of the yield is still a limiting factor.

Results The isotopic ratio of 40Ar/36Ar, using the 1012 Ω amplifier for 36Ar, gave a value of 308 ± 0.90 and the standard error among the samples ranged from 1.3 to 3.09, whereas using the CDD configuration (for 36Ar) the value of 40Ar/36Ar was 304.86 ± 0.56 and a standard error among the samples ranged from 0.21 to 0.45.

With the new 1013 Ω amplifier, used for 36Ar, we were able to achieve the following results: 40Ar/36Ar = 312.05 ± 0.55 and a standard error among the samples ranged from 0.40 to 1.37. (For this analysis the new 1013 Ω was not calibrated to the 1012 Ω). 38Ar/36Ar ratios were 0.1958 ± 0.0008, 0.1923 ± 0.0007 and 0.1981 ± 0.0005; respectively for 36Ar measured on: the Faraday cup with the 1012 Ω amplifiers, the CDD and the Faraday cup with the 1013 Ω amplifiers.

Calibration of the New Amplifier with a 1013 Ω Resistor

The 1013 Ω amplifier is by design 10 times more sensitive than the corresponding 1012 Ω amplifier. Given this increased sensitivity, at this time, it is not possible to calibrate the new 1013 Ω amplifier with the existing cross calibration system, as is routinely done on the 1011 Ω and 1012 Ω amplifiers fitted to the Helix MC Plus. A reference / standard should be used to calibrate the 1013 Ω amplifier.

Microsoft and Excel are trademarks of Microsoft Corp All other trademarks are the property of Thermo Fisher Scientific and its subsidiaries. This information is not intended to encourage use of these products in any manners that might infringe the intellectual property rights of others. Presented at Goldschmidt 2014, Sacramento, CA, 6/2014.

FIGURE 3. 40Ar/36Ar AIR. Comparison among CDD/CDD, CDD/Faraday 1012 Ω amplifier and CDD/Faraday 1013 Ω amplifier. The 1013 Ω amplifier was not gain calibrated. This is why there is a bias in the absolute ratio.

FIGURE 4. 38Ar/36Ar AIR. Comparison among CDD/CDD, CDD/Faraday 1012 Ω amplifier and CDD/Faraday 1013 Ω amplifier. The 1013 Ω amplifier was not gain calibrated. This is why there is a bias in the absolute ratio.

High Resolution Mass Spectrometer

One of the key features of the HELIX MC Plus noble gas MS is its high resolution capability. The instrument utilizes a large radius geometry and is capable to achieve a resolution > 1500 and a resolving power > 5000 (routinely >7000) when using the high resolution entrance slit.

New Multi-Collector Mass Spectrometry Data for Noble Gases Analysis Alessandro Santato1, Doug Hamilton1, Jan Wijbrans2, Claudia Bouman1 1Thermo Fisher Scientific, Bremen, Germany 2VU University Amsterdam, Faculty of Earth and Life Sciences, Amsterdam, The Netherlands

Acknowledgements This project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 316966.

We gratefully thank Prof. Masahiko Honda from ANU Canberra for the two high resolution Neon scans.

We would also like to thank the following person for their constant support: Soehnke Rathmann (test field engineer), Andreas Trint (test field engineer), Alexander Duhr (support noble gas MS), Peter Komander (electronic engineer), Michael Deerberg (R&D department).

Future Work Further important steps in small sample analysis of noble gases will involve the development of an appropriate gain calibration technique for the new amplifiers as well as the improvement of the yield calibration for the electron multipliers during multi-collector analysis.

FIGURE 1. Scheme showing the three different multi-collector settings used in this work.

FIGURE 2. Thermo Scientific HELIX MC Plus noble gas MS (right) and NG Prep System (left).

FIGURE 7. Resolution of the three interferences of 20Ne (top) and resolution of 21Ne from 20NeH (bottom).

FIGURE 6. Complete resolution of 36Ar from the hydrocarbon interference 12C3 and partial resolution from the H35Cl.

Current amplifier Noise Decay

1011 Ohm ≤0.2 ftA (20 µV) @ 4 s 10 ppm in 2 s

1013 Ohm ≤50 atA (5 µV) @ 4 s 100 ppm in 8 s

FIGURE 5. Specifications of the 1013 Ω amplifier compared with the 1011 Ω amplifier.

2 New Multi-Collector Mass Spectrometry Data for Noble Gases Analysis

Overview Purpose: We test the performance of new high gain amplifiers equipped with 1013 Ω feedback resistors. The tests are carried out on the multi-collector Thermo Scientific™ HELIX MC Plus™ noble gas MS.

Methods: Circa 2.4 x 10-13 mole of argon was analyzed using three different multi-collector modes and 40Ar/36Ar and 38Ar/36Ar was measured.

Results: The new 1013 Ω amplifier show a decisive improvement in the measurement of small samples.

Introduction On the Earth, noble gases are present as rare elements and in most of the cases their concentration within samples is extremely low. Therefore their analysis requires a high detection efficiency which implies ultra high vacuum systems, mass spectrometers able to operate in static mode, and detectors capable of reading small signals. Here we present a comparison between the latest amplifiers equipped with 1013 Ω resistors and the established state-of-art Thermo Scientific detector technology, represented by: 1012 amplifiers and the latest electron multiplier: Compact Discrete Dynode™ (CDD).

Methods

Sample Preparation and Analysis

Argon from atmospheric air was prepared with the Thermo Scientific NG Prep System™ and used as standard sample for all the tests.

Circa 2.4 x 10-13 mol of argon were repeatedly analyzed using three different collector configurations.

Collector Configurations

Argon mass 40, 38 and 36 were analyzed using three different multi-collector modes, see figure 1.

40Ar and 38Ar were always analyzed, respectively: on a Faraday cup coupled with a 1011 Ω amplifier and on an electron multiplier CDD. The 36Ar was analyzed with three different detector configurations: a Faraday cup coupled with the 1012 Ω amplifier, an electron multiplier CDD and a Faraday cup coupled with the latest 1013 Ω amplifier.

Mass Spectrometry

The Thermo Scientific HELIX MC Plus multi-collector static vacuum mass spectrometer is the ultimate solution for noble gas analysis. Equipped with a high-resolution magnetic sector analyzer and with a variable multi collector array, which incorporates 5 Combined Faraday Multiplier (CFM) detectors, and is capable of analyzing up to five isotopes of neon, argon, krypton and xenon simultaneously, at new levels of resolution.

Data Analysis

Thermo Scientific Qtegra™ Intelligent Scientific Data Solution™ (ISDS) was used for data acquisition and control software. Plots were made using Microsoft™ Office Excel™ 2007.

Conclusion The higher sensitivity of the new amplifiers equipped

with a 1013 Ω feedback resistor represents a decisive improvement in small sample analysis.

In the 40Ar/36Ar measurement the new 1013 Ω amplifier is capable of achieving a relative standard error between 0.13 and 0.44%, which represents a significant progress if compared with 1012 Ω amplifier (relative standard error is between 0.41 and 1%).

The electron multiplier is the best detector in terms of sensitivity but its drift due to the variation of the yield is still a limiting factor.

Results The isotopic ratio of 40Ar/36Ar, using the 1012 Ω amplifier for 36Ar, gave a value of 308 ± 0.90 and the standard error among the samples ranged from 1.3 to 3.09, whereas using the CDD configuration (for 36Ar) the value of 40Ar/36Ar was 304.86 ± 0.56 and a standard error among the samples ranged from 0.21 to 0.45.

With the new 1013 Ω amplifier, used for 36Ar, we were able to achieve the following results: 40Ar/36Ar = 312.05 ± 0.55 and a standard error among the samples ranged from 0.40 to 1.37. (For this analysis the new 1013 Ω was not calibrated to the 1012 Ω). 38Ar/36Ar ratios were 0.1958 ± 0.0008, 0.1923 ± 0.0007 and 0.1981 ± 0.0005; respectively for 36Ar measured on: the Faraday cup with the 1012 Ω amplifiers, the CDD and the Faraday cup with the 1013 Ω amplifiers.

Calibration of the New Amplifier with a 1013 Ω Resistor

The 1013 Ω amplifier is by design 10 times more sensitive than the corresponding 1012 Ω amplifier. Given this increased sensitivity, at this time, it is not possible to calibrate the new 1013 Ω amplifier with the existing cross calibration system, as is routinely done on the 1011 Ω and 1012 Ω amplifiers fitted to the Helix MC Plus. A reference / standard should be used to calibrate the 1013 Ω amplifier.

Microsoft and Excel are trademarks of Microsoft Corp All other trademarks are the property of Thermo Fisher Scientific and its subsidiaries. This information is not intended to encourage use of these products in any manners that might infringe the intellectual property rights of others. Presented at Goldschmidt 2014, Sacramento, CA, 6/2014.

FIGURE 3. 40Ar/36Ar AIR. Comparison among CDD/CDD, CDD/Faraday 1012 Ω amplifier and CDD/Faraday 1013 Ω amplifier. The 1013 Ω amplifier was not gain calibrated. This is why there is a bias in the absolute ratio.

FIGURE 4. 38Ar/36Ar AIR. Comparison among CDD/CDD, CDD/Faraday 1012 Ω amplifier and CDD/Faraday 1013 Ω amplifier. The 1013 Ω amplifier was not gain calibrated. This is why there is a bias in the absolute ratio.

High Resolution Mass Spectrometer

One of the key features of the HELIX MC Plus noble gas MS is its high resolution capability. The instrument utilizes a large radius geometry and is capable to achieve a resolution > 1500 and a resolving power > 5000 (routinely >7000) when using the high resolution entrance slit.

New Multi-Collector Mass Spectrometry Data for Noble Gases Analysis Alessandro Santato1, Doug Hamilton1, Jan Wijbrans2, Claudia Bouman1 1Thermo Fisher Scientific, Bremen, Germany 2VU University Amsterdam, Faculty of Earth and Life Sciences, Amsterdam, The Netherlands

Acknowledgements This project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 316966.

We gratefully thank Prof. Masahiko Honda from ANU Canberra for the two high resolution Neon scans.

We would also like to thank the following person for their constant support: Soehnke Rathmann (test field engineer), Andreas Trint (test field engineer), Alexander Duhr (support noble gas MS), Peter Komander (electronic engineer), Michael Deerberg (R&D department).

Future Work Further important steps in small sample analysis of noble gases will involve the development of an appropriate gain calibration technique for the new amplifiers as well as the improvement of the yield calibration for the electron multipliers during multi-collector analysis.

FIGURE 1. Scheme showing the three different multi-collector settings used in this work.

FIGURE 2. Thermo Scientific HELIX MC Plus noble gas MS (right) and NG Prep System (left).

FIGURE 7. Resolution of the three interferences of 20Ne (top) and resolution of 21Ne from 20NeH (bottom).

FIGURE 6. Complete resolution of 36Ar from the hydrocarbon interference 12C3 and partial resolution from the H35Cl.

Current amplifier Noise Decay

1011 Ohm ≤0.2 ftA (20 µV) @ 4 s 10 ppm in 2 s

1013 Ohm ≤50 atA (5 µV) @ 4 s 100 ppm in 8 s

FIGURE 5. Specifications of the 1013 Ω amplifier compared with the 1011 Ω amplifier.

3Thermo Scientific Poster Note • PN-SANTATO-GOLDSCHMIDT-2014-EN-0614S

Overview Purpose: We test the performance of new high gain amplifiers equipped with 1013 Ω feedback resistors. The tests are carried out on the multi-collector Thermo Scientific™ HELIX MC Plus™ noble gas MS.

Methods: Circa 2.4 x 10-13 mole of argon was analyzed using three different multi-collector modes and 40Ar/36Ar and 38Ar/36Ar was measured.

Results: The new 1013 Ω amplifier show a decisive improvement in the measurement of small samples.

Introduction On the Earth, noble gases are present as rare elements and in most of the cases their concentration within samples is extremely low. Therefore their analysis requires a high detection efficiency which implies ultra high vacuum systems, mass spectrometers able to operate in static mode, and detectors capable of reading small signals. Here we present a comparison between the latest amplifiers equipped with 1013 Ω resistors and the established state-of-art Thermo Scientific detector technology, represented by: 1012 amplifiers and the latest electron multiplier: Compact Discrete Dynode™ (CDD).

Methods

Sample Preparation and Analysis

Argon from atmospheric air was prepared with the Thermo Scientific NG Prep System™ and used as standard sample for all the tests.

Circa 2.4 x 10-13 mol of argon were repeatedly analyzed using three different collector configurations.

Collector Configurations

Argon mass 40, 38 and 36 were analyzed using three different multi-collector modes, see figure 1.

40Ar and 38Ar were always analyzed, respectively: on a Faraday cup coupled with a 1011 Ω amplifier and on an electron multiplier CDD. The 36Ar was analyzed with three different detector configurations: a Faraday cup coupled with the 1012 Ω amplifier, an electron multiplier CDD and a Faraday cup coupled with the latest 1013 Ω amplifier.

Mass Spectrometry

The Thermo Scientific HELIX MC Plus multi-collector static vacuum mass spectrometer is the ultimate solution for noble gas analysis. Equipped with a high-resolution magnetic sector analyzer and with a variable multi collector array, which incorporates 5 Combined Faraday Multiplier (CFM) detectors, and is capable of analyzing up to five isotopes of neon, argon, krypton and xenon simultaneously, at new levels of resolution.

Data Analysis

Thermo Scientific Qtegra™ Intelligent Scientific Data Solution™ (ISDS) was used for data acquisition and control software. Plots were made using Microsoft™ Office Excel™ 2007.

Conclusion The higher sensitivity of the new amplifiers equipped

with a 1013 Ω feedback resistor represents a decisive improvement in small sample analysis.

In the 40Ar/36Ar measurement the new 1013 Ω amplifier is capable of achieving a relative standard error between 0.13 and 0.44%, which represents a significant progress if compared with 1012 Ω amplifier (relative standard error is between 0.41 and 1%).

The electron multiplier is the best detector in terms of sensitivity but its drift due to the variation of the yield is still a limiting factor.

Results The isotopic ratio of 40Ar/36Ar, using the 1012 Ω amplifier for 36Ar, gave a value of 308 ± 0.90 and the standard error among the samples ranged from 1.3 to 3.09, whereas using the CDD configuration (for 36Ar) the value of 40Ar/36Ar was 304.86 ± 0.56 and a standard error among the samples ranged from 0.21 to 0.45.

With the new 1013 Ω amplifier, used for 36Ar, we were able to achieve the following results: 40Ar/36Ar = 312.05 ± 0.55 and a standard error among the samples ranged from 0.40 to 1.37. (For this analysis the new 1013 Ω was not calibrated to the 1012 Ω). 38Ar/36Ar ratios were 0.1958 ± 0.0008, 0.1923 ± 0.0007 and 0.1981 ± 0.0005; respectively for 36Ar measured on: the Faraday cup with the 1012 Ω amplifiers, the CDD and the Faraday cup with the 1013 Ω amplifiers.

Calibration of the New Amplifier with a 1013 Ω Resistor

The 1013 Ω amplifier is by design 10 times more sensitive than the corresponding 1012 Ω amplifier. Given this increased sensitivity, at this time, it is not possible to calibrate the new 1013 Ω amplifier with the existing cross calibration system, as is routinely done on the 1011 Ω and 1012 Ω amplifiers fitted to the Helix MC Plus. A reference / standard should be used to calibrate the 1013 Ω amplifier.

Microsoft and Excel are trademarks of Microsoft Corp All other trademarks are the property of Thermo Fisher Scientific and its subsidiaries. This information is not intended to encourage use of these products in any manners that might infringe the intellectual property rights of others. Presented at Goldschmidt 2014, Sacramento, CA, 6/2014.

FIGURE 3. 40Ar/36Ar AIR. Comparison among CDD/CDD, CDD/Faraday 1012 Ω amplifier and CDD/Faraday 1013 Ω amplifier. The 1013 Ω amplifier was not gain calibrated. This is why there is a bias in the absolute ratio.

FIGURE 4. 38Ar/36Ar AIR. Comparison among CDD/CDD, CDD/Faraday 1012 Ω amplifier and CDD/Faraday 1013 Ω amplifier. The 1013 Ω amplifier was not gain calibrated. This is why there is a bias in the absolute ratio.

High Resolution Mass Spectrometer

One of the key features of the HELIX MC Plus noble gas MS is its high resolution capability. The instrument utilizes a large radius geometry and is capable to achieve a resolution > 1500 and a resolving power > 5000 (routinely >7000) when using the high resolution entrance slit.

New Multi-Collector Mass Spectrometry Data for Noble Gases Analysis Alessandro Santato1, Doug Hamilton1, Jan Wijbrans2, Claudia Bouman1 1Thermo Fisher Scientific, Bremen, Germany 2VU University Amsterdam, Faculty of Earth and Life Sciences, Amsterdam, The Netherlands

Acknowledgements This project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 316966.

We gratefully thank Prof. Masahiko Honda from ANU Canberra for the two high resolution Neon scans.

We would also like to thank the following person for their constant support: Soehnke Rathmann (test field engineer), Andreas Trint (test field engineer), Alexander Duhr (support noble gas MS), Peter Komander (electronic engineer), Michael Deerberg (R&D department).

Future Work Further important steps in small sample analysis of noble gases will involve the development of an appropriate gain calibration technique for the new amplifiers as well as the improvement of the yield calibration for the electron multipliers during multi-collector analysis.

FIGURE 1. Scheme showing the three different multi-collector settings used in this work.

FIGURE 2. Thermo Scientific HELIX MC Plus noble gas MS (right) and NG Prep System (left).

FIGURE 7. Resolution of the three interferences of 20Ne (top) and resolution of 21Ne from 20NeH (bottom).

FIGURE 6. Complete resolution of 36Ar from the hydrocarbon interference 12C3 and partial resolution from the H35Cl.

Current amplifier Noise Decay

1011 Ohm ≤0.2 ftA (20 µV) @ 4 s 10 ppm in 2 s

1013 Ohm ≤50 atA (5 µV) @ 4 s 100 ppm in 8 s

FIGURE 5. Specifications of the 1013 Ω amplifier compared with the 1011 Ω amplifier.

4 New Multi-Collector Mass Spectrometry Data for Noble Gases Analysis

Overview Purpose: We test the performance of new high gain amplifiers equipped with 1013 Ω feedback resistors. The tests are carried out on the multi-collector Thermo Scientific™ HELIX MC Plus™ noble gas MS.

Methods: Circa 2.4 x 10-13 mole of argon was analyzed using three different multi-collector modes and 40Ar/36Ar and 38Ar/36Ar was measured.

Results: The new 1013 Ω amplifier show a decisive improvement in the measurement of small samples.

Introduction On the Earth, noble gases are present as rare elements and in most of the cases their concentration within samples is extremely low. Therefore their analysis requires a high detection efficiency which implies ultra high vacuum systems, mass spectrometers able to operate in static mode, and detectors capable of reading small signals. Here we present a comparison between the latest amplifiers equipped with 1013 Ω resistors and the established state-of-art Thermo Scientific detector technology, represented by: 1012 amplifiers and the latest electron multiplier: Compact Discrete Dynode™ (CDD).

Methods

Sample Preparation and Analysis

Argon from atmospheric air was prepared with the Thermo Scientific NG Prep System™ and used as standard sample for all the tests.

Circa 2.4 x 10-13 mol of argon were repeatedly analyzed using three different collector configurations.

Collector Configurations

Argon mass 40, 38 and 36 were analyzed using three different multi-collector modes, see figure 1.

40Ar and 38Ar were always analyzed, respectively: on a Faraday cup coupled with a 1011 Ω amplifier and on an electron multiplier CDD. The 36Ar was analyzed with three different detector configurations: a Faraday cup coupled with the 1012 Ω amplifier, an electron multiplier CDD and a Faraday cup coupled with the latest 1013 Ω amplifier.

Mass Spectrometry

The Thermo Scientific HELIX MC Plus multi-collector static vacuum mass spectrometer is the ultimate solution for noble gas analysis. Equipped with a high-resolution magnetic sector analyzer and with a variable multi collector array, which incorporates 5 Combined Faraday Multiplier (CFM) detectors, and is capable of analyzing up to five isotopes of neon, argon, krypton and xenon simultaneously, at new levels of resolution.

Data Analysis

Thermo Scientific Qtegra™ Intelligent Scientific Data Solution™ (ISDS) was used for data acquisition and control software. Plots were made using Microsoft™ Office Excel™ 2007.

Conclusion The higher sensitivity of the new amplifiers equipped

with a 1013 Ω feedback resistor represents a decisive improvement in small sample analysis.

In the 40Ar/36Ar measurement the new 1013 Ω amplifier is capable of achieving a relative standard error between 0.13 and 0.44%, which represents a significant progress if compared with 1012 Ω amplifier (relative standard error is between 0.41 and 1%).

The electron multiplier is the best detector in terms of sensitivity but its drift due to the variation of the yield is still a limiting factor.

Results The isotopic ratio of 40Ar/36Ar, using the 1012 Ω amplifier for 36Ar, gave a value of 308 ± 0.90 and the standard error among the samples ranged from 1.3 to 3.09, whereas using the CDD configuration (for 36Ar) the value of 40Ar/36Ar was 304.86 ± 0.56 and a standard error among the samples ranged from 0.21 to 0.45.

With the new 1013 Ω amplifier, used for 36Ar, we were able to achieve the following results: 40Ar/36Ar = 312.05 ± 0.55 and a standard error among the samples ranged from 0.40 to 1.37. (For this analysis the new 1013 Ω was not calibrated to the 1012 Ω). 38Ar/36Ar ratios were 0.1958 ± 0.0008, 0.1923 ± 0.0007 and 0.1981 ± 0.0005; respectively for 36Ar measured on: the Faraday cup with the 1012 Ω amplifiers, the CDD and the Faraday cup with the 1013 Ω amplifiers.

Calibration of the New Amplifier with a 1013 Ω Resistor

The 1013 Ω amplifier is by design 10 times more sensitive than the corresponding 1012 Ω amplifier. Given this increased sensitivity, at this time, it is not possible to calibrate the new 1013 Ω amplifier with the existing cross calibration system, as is routinely done on the 1011 Ω and 1012 Ω amplifiers fitted to the Helix MC Plus. A reference / standard should be used to calibrate the 1013 Ω amplifier.

Microsoft and Excel are trademarks of Microsoft Corp All other trademarks are the property of Thermo Fisher Scientific and its subsidiaries. This information is not intended to encourage use of these products in any manners that might infringe the intellectual property rights of others. Presented at Goldschmidt 2014, Sacramento, CA, 6/2014.

FIGURE 3. 40Ar/36Ar AIR. Comparison among CDD/CDD, CDD/Faraday 1012 Ω amplifier and CDD/Faraday 1013 Ω amplifier. The 1013 Ω amplifier was not gain calibrated. This is why there is a bias in the absolute ratio.

FIGURE 4. 38Ar/36Ar AIR. Comparison among CDD/CDD, CDD/Faraday 1012 Ω amplifier and CDD/Faraday 1013 Ω amplifier. The 1013 Ω amplifier was not gain calibrated. This is why there is a bias in the absolute ratio.

High Resolution Mass Spectrometer

One of the key features of the HELIX MC Plus noble gas MS is its high resolution capability. The instrument utilizes a large radius geometry and is capable to achieve a resolution > 1500 and a resolving power > 5000 (routinely >7000) when using the high resolution entrance slit.

New Multi-Collector Mass Spectrometry Data for Noble Gases Analysis Alessandro Santato1, Doug Hamilton1, Jan Wijbrans2, Claudia Bouman1 1Thermo Fisher Scientific, Bremen, Germany 2VU University Amsterdam, Faculty of Earth and Life Sciences, Amsterdam, The Netherlands

Acknowledgements This project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 316966.

We gratefully thank Prof. Masahiko Honda from ANU Canberra for the two high resolution Neon scans.

We would also like to thank the following person for their constant support: Soehnke Rathmann (test field engineer), Andreas Trint (test field engineer), Alexander Duhr (support noble gas MS), Peter Komander (electronic engineer), Michael Deerberg (R&D department).

Future Work Further important steps in small sample analysis of noble gases will involve the development of an appropriate gain calibration technique for the new amplifiers as well as the improvement of the yield calibration for the electron multipliers during multi-collector analysis.

FIGURE 1. Scheme showing the three different multi-collector settings used in this work.

FIGURE 2. Thermo Scientific HELIX MC Plus noble gas MS (right) and NG Prep System (left).

FIGURE 7. Resolution of the three interferences of 20Ne (top) and resolution of 21Ne from 20NeH (bottom).

FIGURE 6. Complete resolution of 36Ar from the hydrocarbon interference 12C3 and partial resolution from the H35Cl.

Current amplifier Noise Decay

1011 Ohm ≤0.2 ftA (20 µV) @ 4 s 10 ppm in 2 s

1013 Ohm ≤50 atA (5 µV) @ 4 s 100 ppm in 8 s

FIGURE 5. Specifications of the 1013 Ω amplifier compared with the 1011 Ω amplifier.

5Thermo Scientific Poster Note • PN-SANTATO-GOLDSCHMIDT-2014-EN-0614S

Overview Purpose: We test the performance of new high gain amplifiers equipped with 1013 Ω feedback resistors. The tests are carried out on the multi-collector Thermo Scientific™ HELIX MC Plus™ noble gas MS.

Methods: Circa 2.4 x 10-13 mole of argon was analyzed using three different multi-collector modes and 40Ar/36Ar and 38Ar/36Ar was measured.

Results: The new 1013 Ω amplifier show a decisive improvement in the measurement of small samples.

Introduction On the Earth, noble gases are present as rare elements and in most of the cases their concentration within samples is extremely low. Therefore their analysis requires a high detection efficiency which implies ultra high vacuum systems, mass spectrometers able to operate in static mode, and detectors capable of reading small signals. Here we present a comparison between the latest amplifiers equipped with 1013 Ω resistors and the established state-of-art Thermo Scientific detector technology, represented by: 1012 amplifiers and the latest electron multiplier: Compact Discrete Dynode™ (CDD).

Methods

Sample Preparation and Analysis

Argon from atmospheric air was prepared with the Thermo Scientific NG Prep System™ and used as standard sample for all the tests.

Circa 2.4 x 10-13 mol of argon were repeatedly analyzed using three different collector configurations.

Collector Configurations

Argon mass 40, 38 and 36 were analyzed using three different multi-collector modes, see figure 1.

40Ar and 38Ar were always analyzed, respectively: on a Faraday cup coupled with a 1011 Ω amplifier and on an electron multiplier CDD. The 36Ar was analyzed with three different detector configurations: a Faraday cup coupled with the 1012 Ω amplifier, an electron multiplier CDD and a Faraday cup coupled with the latest 1013 Ω amplifier.

Mass Spectrometry

The Thermo Scientific HELIX MC Plus multi-collector static vacuum mass spectrometer is the ultimate solution for noble gas analysis. Equipped with a high-resolution magnetic sector analyzer and with a variable multi collector array, which incorporates 5 Combined Faraday Multiplier (CFM) detectors, and is capable of analyzing up to five isotopes of neon, argon, krypton and xenon simultaneously, at new levels of resolution.

Data Analysis

Thermo Scientific Qtegra™ Intelligent Scientific Data Solution™ (ISDS) was used for data acquisition and control software. Plots were made using Microsoft™ Office Excel™ 2007.

Conclusion The higher sensitivity of the new amplifiers equipped

with a 1013 Ω feedback resistor represents a decisive improvement in small sample analysis.

In the 40Ar/36Ar measurement the new 1013 Ω amplifier is capable of achieving a relative standard error between 0.13 and 0.44%, which represents a significant progress if compared with 1012 Ω amplifier (relative standard error is between 0.41 and 1%).

The electron multiplier is the best detector in terms of sensitivity but its drift due to the variation of the yield is still a limiting factor.

Results The isotopic ratio of 40Ar/36Ar, using the 1012 Ω amplifier for 36Ar, gave a value of 308 ± 0.90 and the standard error among the samples ranged from 1.3 to 3.09, whereas using the CDD configuration (for 36Ar) the value of 40Ar/36Ar was 304.86 ± 0.56 and a standard error among the samples ranged from 0.21 to 0.45.

With the new 1013 Ω amplifier, used for 36Ar, we were able to achieve the following results: 40Ar/36Ar = 312.05 ± 0.55 and a standard error among the samples ranged from 0.40 to 1.37. (For this analysis the new 1013 Ω was not calibrated to the 1012 Ω). 38Ar/36Ar ratios were 0.1958 ± 0.0008, 0.1923 ± 0.0007 and 0.1981 ± 0.0005; respectively for 36Ar measured on: the Faraday cup with the 1012 Ω amplifiers, the CDD and the Faraday cup with the 1013 Ω amplifiers.

Calibration of the New Amplifier with a 1013 Ω Resistor

The 1013 Ω amplifier is by design 10 times more sensitive than the corresponding 1012 Ω amplifier. Given this increased sensitivity, at this time, it is not possible to calibrate the new 1013 Ω amplifier with the existing cross calibration system, as is routinely done on the 1011 Ω and 1012 Ω amplifiers fitted to the Helix MC Plus. A reference / standard should be used to calibrate the 1013 Ω amplifier.

Microsoft and Excel are trademarks of Microsoft Corp All other trademarks are the property of Thermo Fisher Scientific and its subsidiaries. This information is not intended to encourage use of these products in any manners that might infringe the intellectual property rights of others. Presented at Goldschmidt 2014, Sacramento, CA, 6/2014.

FIGURE 3. 40Ar/36Ar AIR. Comparison among CDD/CDD, CDD/Faraday 1012 Ω amplifier and CDD/Faraday 1013 Ω amplifier. The 1013 Ω amplifier was not gain calibrated. This is why there is a bias in the absolute ratio.

FIGURE 4. 38Ar/36Ar AIR. Comparison among CDD/CDD, CDD/Faraday 1012 Ω amplifier and CDD/Faraday 1013 Ω amplifier. The 1013 Ω amplifier was not gain calibrated. This is why there is a bias in the absolute ratio.

High Resolution Mass Spectrometer

One of the key features of the HELIX MC Plus noble gas MS is its high resolution capability. The instrument utilizes a large radius geometry and is capable to achieve a resolution > 1500 and a resolving power > 5000 (routinely >7000) when using the high resolution entrance slit.

New Multi-Collector Mass Spectrometry Data for Noble Gases Analysis Alessandro Santato1, Doug Hamilton1, Jan Wijbrans2, Claudia Bouman1 1Thermo Fisher Scientific, Bremen, Germany 2VU University Amsterdam, Faculty of Earth and Life Sciences, Amsterdam, The Netherlands

Acknowledgements This project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 316966.

We gratefully thank Prof. Masahiko Honda from ANU Canberra for the two high resolution Neon scans.

We would also like to thank the following person for their constant support: Soehnke Rathmann (test field engineer), Andreas Trint (test field engineer), Alexander Duhr (support noble gas MS), Peter Komander (electronic engineer), Michael Deerberg (R&D department).

Future Work Further important steps in small sample analysis of noble gases will involve the development of an appropriate gain calibration technique for the new amplifiers as well as the improvement of the yield calibration for the electron multipliers during multi-collector analysis.

FIGURE 1. Scheme showing the three different multi-collector settings used in this work.

FIGURE 2. Thermo Scientific HELIX MC Plus noble gas MS (right) and NG Prep System (left).

FIGURE 7. Resolution of the three interferences of 20Ne (top) and resolution of 21Ne from 20NeH (bottom).

FIGURE 6. Complete resolution of 36Ar from the hydrocarbon interference 12C3 and partial resolution from the H35Cl.

Current amplifier Noise Decay

1011 Ohm ≤0.2 ftA (20 µV) @ 4 s 10 ppm in 2 s

1013 Ohm ≤50 atA (5 µV) @ 4 s 100 ppm in 8 s

FIGURE 5. Specifications of the 1013 Ω amplifier compared with the 1011 Ω amplifier.

6 New Multi-Collector Mass Spectrometry Data for Noble Gases Analysis

Overview Purpose: We test the performance of new high gain amplifiers equipped with 1013 Ω feedback resistors. The tests are carried out on the multi-collector Thermo Scientific™ HELIX MC Plus™ noble gas MS.

Methods: Circa 2.4 x 10-13 mole of argon was analyzed using three different multi-collector modes and 40Ar/36Ar and 38Ar/36Ar was measured.

Results: The new 1013 Ω amplifier show a decisive improvement in the measurement of small samples.

Introduction On the Earth, noble gases are present as rare elements and in most of the cases their concentration within samples is extremely low. Therefore their analysis requires a high detection efficiency which implies ultra high vacuum systems, mass spectrometers able to operate in static mode, and detectors capable of reading small signals. Here we present a comparison between the latest amplifiers equipped with 1013 Ω resistors and the established state-of-art Thermo Scientific detector technology, represented by: 1012 amplifiers and the latest electron multiplier: Compact Discrete Dynode™ (CDD).

Methods

Sample Preparation and Analysis

Argon from atmospheric air was prepared with the Thermo Scientific NG Prep System™ and used as standard sample for all the tests.

Circa 2.4 x 10-13 mol of argon were repeatedly analyzed using three different collector configurations.

Collector Configurations

Argon mass 40, 38 and 36 were analyzed using three different multi-collector modes, see figure 1.

40Ar and 38Ar were always analyzed, respectively: on a Faraday cup coupled with a 1011 Ω amplifier and on an electron multiplier CDD. The 36Ar was analyzed with three different detector configurations: a Faraday cup coupled with the 1012 Ω amplifier, an electron multiplier CDD and a Faraday cup coupled with the latest 1013 Ω amplifier.

Mass Spectrometry

The Thermo Scientific HELIX MC Plus multi-collector static vacuum mass spectrometer is the ultimate solution for noble gas analysis. Equipped with a high-resolution magnetic sector analyzer and with a variable multi collector array, which incorporates 5 Combined Faraday Multiplier (CFM) detectors, and is capable of analyzing up to five isotopes of neon, argon, krypton and xenon simultaneously, at new levels of resolution.

Data Analysis

Thermo Scientific Qtegra™ Intelligent Scientific Data Solution™ (ISDS) was used for data acquisition and control software. Plots were made using Microsoft™ Office Excel™ 2007.

Conclusion The higher sensitivity of the new amplifiers equipped

with a 1013 Ω feedback resistor represents a decisive improvement in small sample analysis.

In the 40Ar/36Ar measurement the new 1013 Ω amplifier is capable of achieving a relative standard error between 0.13 and 0.44%, which represents a significant progress if compared with 1012 Ω amplifier (relative standard error is between 0.41 and 1%).

The electron multiplier is the best detector in terms of sensitivity but its drift due to the variation of the yield is still a limiting factor.

Results The isotopic ratio of 40Ar/36Ar, using the 1012 Ω amplifier for 36Ar, gave a value of 308 ± 0.90 and the standard error among the samples ranged from 1.3 to 3.09, whereas using the CDD configuration (for 36Ar) the value of 40Ar/36Ar was 304.86 ± 0.56 and a standard error among the samples ranged from 0.21 to 0.45.

With the new 1013 Ω amplifier, used for 36Ar, we were able to achieve the following results: 40Ar/36Ar = 312.05 ± 0.55 and a standard error among the samples ranged from 0.40 to 1.37. (For this analysis the new 1013 Ω was not calibrated to the 1012 Ω). 38Ar/36Ar ratios were 0.1958 ± 0.0008, 0.1923 ± 0.0007 and 0.1981 ± 0.0005; respectively for 36Ar measured on: the Faraday cup with the 1012 Ω amplifiers, the CDD and the Faraday cup with the 1013 Ω amplifiers.

Calibration of the New Amplifier with a 1013 Ω Resistor

The 1013 Ω amplifier is by design 10 times more sensitive than the corresponding 1012 Ω amplifier. Given this increased sensitivity, at this time, it is not possible to calibrate the new 1013 Ω amplifier with the existing cross calibration system, as is routinely done on the 1011 Ω and 1012 Ω amplifiers fitted to the Helix MC Plus. A reference / standard should be used to calibrate the 1013 Ω amplifier.

Microsoft and Excel are trademarks of Microsoft Corp All other trademarks are the property of Thermo Fisher Scientific and its subsidiaries. This information is not intended to encourage use of these products in any manners that might infringe the intellectual property rights of others. Presented at Goldschmidt 2014, Sacramento, CA, 6/2014.

FIGURE 3. 40Ar/36Ar AIR. Comparison among CDD/CDD, CDD/Faraday 1012 Ω amplifier and CDD/Faraday 1013 Ω amplifier. The 1013 Ω amplifier was not gain calibrated. This is why there is a bias in the absolute ratio.

FIGURE 4. 38Ar/36Ar AIR. Comparison among CDD/CDD, CDD/Faraday 1012 Ω amplifier and CDD/Faraday 1013 Ω amplifier. The 1013 Ω amplifier was not gain calibrated. This is why there is a bias in the absolute ratio.

High Resolution Mass Spectrometer

One of the key features of the HELIX MC Plus noble gas MS is its high resolution capability. The instrument utilizes a large radius geometry and is capable to achieve a resolution > 1500 and a resolving power > 5000 (routinely >7000) when using the high resolution entrance slit.

New Multi-Collector Mass Spectrometry Data for Noble Gases Analysis Alessandro Santato1, Doug Hamilton1, Jan Wijbrans2, Claudia Bouman1 1Thermo Fisher Scientific, Bremen, Germany 2VU University Amsterdam, Faculty of Earth and Life Sciences, Amsterdam, The Netherlands

Acknowledgements This project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 316966.

We gratefully thank Prof. Masahiko Honda from ANU Canberra for the two high resolution Neon scans.

We would also like to thank the following person for their constant support: Soehnke Rathmann (test field engineer), Andreas Trint (test field engineer), Alexander Duhr (support noble gas MS), Peter Komander (electronic engineer), Michael Deerberg (R&D department).

Future Work Further important steps in small sample analysis of noble gases will involve the development of an appropriate gain calibration technique for the new amplifiers as well as the improvement of the yield calibration for the electron multipliers during multi-collector analysis.

FIGURE 1. Scheme showing the three different multi-collector settings used in this work.

FIGURE 2. Thermo Scientific HELIX MC Plus noble gas MS (right) and NG Prep System (left).

FIGURE 7. Resolution of the three interferences of 20Ne (top) and resolution of 21Ne from 20NeH (bottom).

FIGURE 6. Complete resolution of 36Ar from the hydrocarbon interference 12C3 and partial resolution from the H35Cl.

Current amplifier Noise Decay

1011 Ohm ≤0.2 ftA (20 µV) @ 4 s 10 ppm in 2 s

1013 Ohm ≤50 atA (5 µV) @ 4 s 100 ppm in 8 s

FIGURE 5. Specifications of the 1013 Ω amplifier compared with the 1011 Ω amplifier.

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OverviewPurpose: We test the performance of new high gain amplifiers equipped with 1013 Ω feedback resistors. Thetests are carried out on the multi-collector Thermo Scientific™ HELIX MC Plus™ noble gas MS.

Methods: Circa 2.4 x 10-13 mole of argon was analyzed using three different multi-collector modes and 40Ar/36Ar and 38Ar/36Ar was measured.

Results: The new 1013 Ω amplifier show a decisive improvement in the measurement of small samples.

IntroductionOn the Earth, noble gases are present as rare elements and in most of the cases their concentration within samples is extremely low. Therefore their analysis requires a high detection efficiency which implies ultra high vacuum systems, mass spectrometers able to operate in static mode, and detectors capable of reading small signals. Here we present a comparison between the latest amplifiers equipped with 1013 Ω resistors and the established state-of-art Thermo Scientific detector technology, represented by: 1012 amplifiers and the latestelectron multiplier: Compact Discrete Dynode™ (CDD).

MethodsSample Preparation and Analysis

Argon from atmospheric air was prepared with the Thermo Scientific NG Prep System™ and used as standard sample for all the tests.

Circa 2.4 x 10-13 mol of argon were repeatedly analyzed using three different collector configurations.

Collector Configurations

Argon mass 40, 38 and 36 were analyzed using three different multi-collector modes, see figure 1.

40Ar and 38Ar were always analyzed, respectively: on a Faraday cup coupled with a 1011 Ω amplifier and on an electron multiplier CDD. The 36Ar was analyzed with three different detector configurations: a Faraday cup coupled with the 1012 Ω amplifier, an electron multiplier CDD and a Faraday cup coupled with the latest 1013 Ω amplifier.

Mass Spectrometry

The Thermo Scientific HELIX MC Plus multi-collector static vacuum mass spectrometer is the ultimate solution for noble gas analysis. Equipped with a high-resolution magnetic sector analyzer and with a variable multi collector array, which incorporates 5 Combined Faraday Multiplier (CFM) detectors, and is capable of analyzing up to five isotopes of neon, argon, krypton and xenon simultaneously, at new levels of resolution.

Data Analysis

Thermo Scientific Qtegra™ Intelligent Scientific Data Solution™ (ISDS) was used for data acquisition andcontrol software. Plots were made using Microsoft™ Office Excel™ 2007.

Conclusion The higher sensitivity of the new amplifiers equipped

with a 1013 Ω feedback resistor represents a decisiveimprovement in small sample analysis.

In the 40Ar/36Ar measurement the new 1013 Ω amplifieris capable of achieving a relative standard errorbetween 0.13 and 0.44%, which represents asignificant progress if compared with 1012 Ω amplifier(relative standard error is between 0.41 and 1%).

The electron multiplier is the best detector in terms ofsensitivity but its drift due to the variation of the yield isstill a limiting factor.

ResultsThe isotopic ratio of 40Ar/36Ar, using the 1012 Ω amplifier for 36Ar, gave a value of 308 ± 0.90 and the standard error among the samples ranged from 1.3 to 3.09, whereas using the CDD configuration (for 36Ar) the value of 40Ar/36Ar was 304.86 ± 0.56 and a standard error among the samples ranged from 0.21 to 0.45.

With the new 1013 Ω amplifier, used for 36Ar, we were able to achieve the following results: 40Ar/36Ar = 312.05 ± 0.55and a standard error among the samples ranged from 0.40to 1.37. (For this analysis the new 1013 Ω was not calibrated to the 1012 Ω).38Ar/36Ar ratios were 0.1958 ± 0.0008, 0.1923 ± 0.0007 and0.1981 ± 0.0005; respectively for 36Ar measured on: the Faraday cup with the 1012 Ω amplifiers, the CDD and the Faraday cup with the 1013 Ω amplifiers.

Calibration of the New Amplifier with a 1013 Ω Resistor

The 1013 Ω amplifier is by design 10 times more sensitive than the corresponding 1012 Ω amplifier. Given this increased sensitivity, at this time, it is not possible to calibrate the new 1013 Ω amplifier with the existing cross calibration system, as is routinely done on the 1011 Ω and 1012 Ω amplifiers fitted to the Helix MC Plus. A reference / standard should be used to calibrate the 1013 Ω amplifier.

Microsoft and Excel are trademarks of Microsoft Corp All other trademarks are the property of Thermo Fisher Scientific and its subsidiaries. This information is not intended to encourage use of these products in any manners that might infringe the intellectual property rights of others. Presented at Goldschmidt 2014, Sacramento, CA, 6/2014.

FIGURE 3. 40Ar/36Ar AIR. Comparison among CDD/CDD, CDD/Faraday 1012 Ω amplifier and CDD/Faraday 1013 Ωamplifier. The 1013 Ω amplifier was not gain calibrated.This is why there is a bias in the absolute ratio.

FIGURE 4. 38Ar/36Ar AIR. Comparison among CDD/CDD, CDD/Faraday 1012 Ω amplifier andCDD/Faraday 1013 Ω amplifier. The 1013 Ω amplifier was not gain calibrated. This is why there is a bias inthe absolute ratio.

High Resolution Mass Spectrometer

One of the key features of the HELIX MC Plus noble gas MS is its high resolution capability. The instrument utilizes a large radius geometry and is capable to achieve a resolution > 1500 and a resolving power > 5000 (routinely >7000) when using the high resolution entrance slit.

New Multi-Collector Mass Spectrometry Data for Noble Gases AnalysisAlessandro Santato1, Doug Hamilton1, Jan Wijbrans2, Claudia Bouman1

1Thermo Fisher Scientific, Bremen, Germany2VU University Amsterdam, Faculty of Earth and Life Sciences, Amsterdam, The Netherlands

Acknowledgements This project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 316966.

We gratefully thank Prof. Masahiko Honda from ANU Canberra for the two high resolution Neon scans.

We would also like to thank the following person for their constant support: Soehnke Rathmann (test field engineer), Andreas Trint (test field engineer), Alexander Duhr (support noble gas MS), Peter Komander (electronic engineer), Michael Deerberg (R&D department).

Future Work Further important steps in small sample analysis of noble gases will involve the development of an appropriate gain calibration technique for the new amplifiers as well as the improvement of the yield calibration for the electron multipliers during multi-collector analysis.

FIGURE 1. Scheme showing the three different multi-collector settings used in this work.

FIGURE 2. Thermo Scientific HELIX MC Plus noble gasMS (right) and NG Prep System (left).

FIGURE 7. Resolution of the three interferences of 20Ne (top) and resolution of 21Ne from 20NeH (bottom).

FIGURE 6. Complete resolution of 36Ar from the hydrocarbon interference 12C3 and partial resolution from the H35Cl.

Current amplifier Noise Decay

1011 Ohm ≤0.2 ftA (20 µV) @ 4 s 10 ppm in 2 s

1013 Ohm ≤50 atA (5 µV) @ 4 s 100 ppm in 8 s

FIGURE 5. Specifications of the 1013 Ω amplifier compared with the 1011 Ω amplifier.