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Virtual SIMS Facility

The virtual SIMS facility at the University of the Witwatersrand is the result of a partnership between the Helmholtz GeoForschungsZentrum (GFZ), in Potsdam Germany and Wits; and was established to benefit the southern African scientific community by providing approved users with ±30 days, per annum, of free instrument time (on the Potsdam 1280-HR) via internet-based remote access.

Secondary Ions Mass Spectrometry (SIMS)

Ion microprobes, also known as secondary ion mass spectrometers, use a finely focused ion beam to sputter the surface of a solid sample. A small percentage of the material liberated from the polished surface is ionised, and these secondary ions are accelerated into a mass spectrometer where they are separated according to their mass-over-charge ratio. Ion microprobes, such as the Potsdam Cameca 1280-HR, offer five commonly used modes of operation for geoscience* applications: 

Diagram Isotope measurements

 

 

*while most commonly applied to geological materials, these same techniques have applications in palaeoscience as well as materials science.

 

Access
  1. Prospective users should first contact the head of the vSIMS facility (Glynn@wits.ac.za) to discuss project feasibility.
  2. Once a plan has been refined, the user will be asked to submit a project proposal (download vis this link: http://sims.gfz-potsdam.de/access/) that will then be forwarded to the head of the SIMS lab in Potsdam as well as an external steering committee.
  3. On final approval, the head of the vSIMS will liaise with the user to assign instrument time and co-ordinate sample preparation and/or pre-characterisation if necessary.
  4. The completed samples need to arrive in Potsdam at least a week prior to the measurement session.
  5. If the user is not able to travel to Johannesburg to be involved in the data collection, they must provide detailed notes on what needs to be measured. Site selection can also be done remotely in advance using the motorized petrographic microscope in Potsdam.
  6. The processed SIMS data along with an analytical methods description is given to the user after the measurement session.
Terms and conditions

By submitting an application for collaborating with the vSIMS facility, you will be agreeing to the following:

  1. Publishing of Results: Unless otherwise agreed to in writing, the data will be used for at least one manuscript which will appear in a scientific journal. It is expected that such a manuscript will be submitted for publication within 12 months of obtaining the SIMS data. Should particular circumstances require a delay in submission then the user should inform the SIMS staff at the earliest possible date.
  2. Preparation of Manuscripts: Manuscripts which are to be submitted for publication should be sent to the SIMS staff member(s) in a timely fashion so that they can review the SIMS component and recommend any points where improvements might be made. They also have the opportunity to comment on the other scientific aspects of the manuscript, though here the final judgement will remain with the lead author.
  3. The SIMS staff member(s) collaborating on the project must appear as a co-author on any manuscripts which arise from the data collected using our instrument.
  4. Information for the GFZ Website: The names and affiliations of the users, the title of the project and the project abstract (taken from the lab access application form) will appear on the GFZ SIMS website 9 months after the data are released to the user. The status of the project will also be indicated on that website.
  5. Open Access Publication: The GFZ is committed to the publication of all work within the framework of open access publishing. Publications using Potsdam SIMS data are to be made freely accessible in an open access environment immediately on publication or - via repositories - no later than six months (natural sciences) after the original publication. Free choice of a peer-reviewed medium of publication, to draw maximum attention to the research result, remains unchanged. If published in an Open Access journal the PI on the project is to inform us immediately upon publication. If the work is published in a subscription journal, then upon acceptance for publication, the PI shall provide the final (pre-typesetting) version of the paper to us. The GFZ library will prepare this in a format for public access, taking embargo periods into account.
  6. Conference Contributions: Any abstracts for scientific conferences which make use of SIMS data are also to be sent to us. A pdf-format file of any posters or a PowerPoint file for a talk should also be sent; these will be published on our SIMS website.
Disclaimer

We continually strive to provide high-quality data. Nonetheless, we shall not be held liable in the event that results from our facility are subject to subsequent revision. Furthermore, we will not be held responsible for samples lost in transit, and it is the users who will bear any costs related to sample preparation and pre-characterisation.

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