SATPC0036293 Tab 04 4 SOW_Redacted.pdf

Statement of Work for the Purchase of a Hiden Analytical EQP-9 quadrupole mass spectrometer and a Hiden Analytical ESPion Langmuir probe

1. Objective/Requirements The goal of the Cold Solar System Objects ISFM project is to investigate and understand the composition, origin, evolution, and chemical processes occurring on the surfaces and in the atmospheres of cold solar system objects (CSSOs). One of the main tasks is to experimentally simulate the atmospheric chemistry occurring on Titan, Pluto, and Triton, using the COsmic SImulation Chamber (COSmIC) at NASA Ames Research Center (ARC).

COSmIC is composed of a vacuum chamber equipped with a pulsed discharge nozzle (PDN) used to generate a planar supersonic jet expansion to cool a gas mixture down to temperatures below 150 K and reducing the pressure to less than 30 mbar. Gas-phase chemistry is induced in the stream of the jet-cooled gas expansion by applying a pulsed high voltage onto electrodes placed along the slit hence generating a pulsed DC plasma discharge. The plasma-induced chemistry leads to the production of increasingly complex neutral and charged molecules in the gas phase. A mass spectrometer is used on COSmIC to monitor the formation of these molecular products in the plasma discharge in real time. The mass spectrometer currently mounted on COSmIC – a Reflectron Time-Of-Flight (Re-TOF) – is a custom-made mass spectrometer that was built by Jordan Inc. Because Paul Jordan has now retired, the Re-TOF mass spectrometer cannot be serviced anymore, leading to a high risk in case the instrument stops working in the future. To overcome this problem, it is essential to purchase a new mass spectrometer enabling the detection of neutrals, radicals, cations, and anions over a wide mass spectral range, with a mass resolution of < 1 amu, and a high sensitivity (ppm). In addition, to determine the impact of plasma parameters on the chemistry and the production of complex species, it is essential to purchase a Langmuir probe that will allow the measurements of the plasma potential, the electron temperature, the ion density, and the flux, i.e., all essential key parameters to characterize the plasma discharge produced in COSmIC.

2. Characteristics, Scope, and Specs

The Quadrupole Mass Spectrometer (QMS) shall allow the detection of neutral molecules, radicals, cations, and anions formed in the plasma discharge generated in COSmIC, over a broad mass spectral range, from 1 to 1,000 amu, with a mass resolution of < 1 amu, and with a sensitivity on the order of ppm level.

To achieve this goal the mass spectrometer will need the following specifications:

- designed for direct in situ analysis of plasma discharges (ion mass and energy)

- include integral electron bombardment ion source, enabling the detection of neutral molecules and radicals formed in a plasma medium

- include an extractor function (to by-pass the ion source) enabling the detection of both positive and negative ions generated in the plasma discharge

- include an energy filter which enables the study of the energy of the molecules present in the plasma medium with 100% transmission within the pass band

- include a quadrupole mass filter which enables the study of the mass-to-charge (m/z) ratios of the molecules present in the plasma medium with an enhanced mass discrimination, abundance sensitivity and contamination resistance

- include a software that not only displays peak intensities as a function of the m/z ratios of the detected molecules, but also enables instrument tuning to detect molecules with a high sensitivity at parts-per-million (ppm) level

- include interchangeable sampling orifices coupled to an 85 L/s turbomolecular pump that will enable different chemical pathways to be studied in plasma discharge generated at different pressures in the COSmIC vacuum chamber

- include a custom-made mobile cart and motorized Z-drive that will enable the measurement of the spatial distribution of molecular masses and energies at different positions in the COSmIC plasma discharge

- include an ultra-high vacuum gate valve that will allow to completely disconnect and isolate the EQP-9 QMS from the COSmIC chamber while keeping the instrument under vacuum

The Hiden Analytical EQP-9 quadrupole mass spectrometer (QMS) and associated MASsoft software (see quote), meet our needs. The quoted instrument includes a custom-made cart that has been specifically designed to fit the COSmIC system (experimental parameters, configuration, and space constraints).

We have conducted market research and compared two different manufacturers of mass spectrometers that allow for negative ion detection: Hiden Analytical specializes in the design and development of high-quality quadrupole mass spectrometers for advanced plasma research applications and is recognized worldwide. It has several technical support branches in North America including one in Solana Beach, CA.

The EQP-9 QMS with the features mentioned above meets our criteria, and with the government discount offered by Hiden Analytical, It is also important to mention that two members of the COSmIC team have extensive experience with the Hiden Analytical EQP-9 QMS.

Langmuir Probe Along with the mass spectrometer that will enable the characterization of the plasma molecular composition, the COSmIC facility requires a Langmuir probe to characterize the intrinsic plasma parameters (floating potential, plasma potential, electron energy distribution, ion flux, ion density, electron density, electron temperature). This Langmuir probe needs to satisfy the following requirements:

- enable a range of standard plasma sampling and characterization options for the DC glow plasma discharge produced in the COSmIC facility.

- allow routine measurement of plasma characteristics for monitoring plasma stability and reproducibility.

- include a software that allows the control of pulsed data acquisition synchronously with the COSmIC pulsed plasma discharge (i.e., a TTL input which enable measurements to be synchronized with an external TTL signal).

- enable automatic extraction of a wide variety of parameters (floating potential, plasma potential, electron energy distribution, ion flux, ion density, electron density, electron temperature) from real-time measurements in the COSmIC plasma discharge.

- include a mechanical system to enable probing the COSmIC plasma discharge at different locations, which is essential to characterize the experimental setup.

Hiden Analytical offers the ESPion Langmuir probe, which is specially developed to enable sampling and characterization of a broad range of plasma discharges including, in particular, DC glow plasma discharges like the one produced in the COSmIC facility. It meets all the requirements listed above. The quote for the ESPion Langmuir probe includes custom-designed spacers specific to the dimensions of the COSmIC vacuum chamber. We have conducted market research and compared three different Langmuir probe manufacturers: , . The ESPion Langmuir Probe with the features mentioned above meets our criteria and with the government discount offered by Hiden Analytical . In addition, the custom-designed spacers for the Hiden Analytical ESPion Langmuir probe, which will use the same port as the EQP-9 QMS, make this probe the most compatible with the COSmIC setup. As for , the Langmuir probe that corresponds to our needs is not sold in North America.

3. Place of Performance

NASA Ames Research Center Mailstop 245-6 Building N245, Room B31 Moffett Field, CA 94035

4. Period of Performance

The two instruments (EQP-9 QMS and ESPion Langmuir probe) are needed by 01/15/2025.