Introduction

The Bruker Tracer 5 is a fully portable analyzer based on energy dispersive X-ray fluorescence (EDXRF) technology. When X-ray radiation from the handheld XRF instruments' X-ray tube (source) excites the atoms in a sample, the atoms release low-energy fluorescent X-rays detected by device's detector. The energy level of each fluorescent X-ray is characteristic of the element excited. As a result, one can tell what elements are present based on the emitted energy patterns of the X-rays. The Bruker Tracer 5 portable XRF (pXRF) allows for elemental measurements on section halves, discrete samples and prepared powder mounts. It is standard for the onboard technician to train one or more scientists in pXRF operation and sample prep. The scientists are then responsible for the work flow during the expedition. 

Before you begin: The instrument generates X-rays and should only be operated by users trained in radiation safety. Do not expose any part of your body to X-rays!

Theory of Operation

X-ray fluorescence is the production of X-rays in the electron orbits. The handheld XRF functions by bombarding the atoms of the target sample with X-rays. Some of the photons collide with K (and L) shell electrons of the sample, dislodging them from their orbits. This leaves a vacant space in the K (L) shell, which is immediately filled by an electron from the L, M, or N (M or N) shell. This is accompanied by a decrease in the atom's energy, and an X-ray photon is emitted with energy equal to this decrease. Since the energy change is uniquely defined for atoms of a given element, it is possible to predict definite frequencies for the emitted X-rays. This means that when electrons are dislodged from atoms, the emitted X-rays are always identical. These X-rays are analyzed with an X-ray detector and the quantity of K shell and/or L shell X-rays detected will be proportional to the number of atoms of the particular element or elements present in the sample.

Instrument and Accessories

Instrument

• Bruker Tracer 5 portable XRF (pXRF) with 5 application calibrations (and associated reference check samples):
  • GeoExploration (CS-M2, Geo/Soil sample)
  • Limestone (Limestone square)
  • Mudrock (Air) (Mudrock square)
  • Mudrock (He) (Mudrock square)
  • Precious Metals 2 (Silver disk)
• Color touch screen
• AC power adaptor
• 3 Lithium ion batteries and battery charger
• 3mm and 8mm collimators
• Filters for Cu, 200µm/Ti, 25µm/Al, 300µm (black) and Al, 76µm  (orange)
• Prolene exam windows
• Holding stand (IODP 3D Printed)

Accessories

• Desktop stand
• Benchtop stand
• Small stage with leaded cup shield
• Shielded holder for section half measurements (IODP 3D Printed)
• Section half brackets with ruler bracket
• Background plate
• Small scissor platform
• Remote trigger cable
• Thermometer/Clock/Humidity Monitor

Computer & Software

• Laptop (IL-53409-XRF)
• Bruker RemoteCTRL (mirrors device screen)
• Bruker Instrument Tools (data management)
• Artax Spectra (for data processing)
• All-in-one Filehub

Safety & General Precautions

The pXRF should be set up in a location that is out of the way with minimal people working nearby, but that is also easily accessible with sufficient space to scan section halves. This should be done without disrupting other workstations or without danger of dropping or mishandling section halves or core material. Typical locations have been the Downhole Lab bench, Paleo Lab bench or Correlators' station, if they are not sailing. Consult with the scientists, co-chiefs, and Lab Officer/Assistant Lab Officers for a preferred location for each expedition. Once set up and it has been established which scientists will be trained to use the device (usually two scientists per shift), dosimeter rings will be issued to each person that will be operating the device and the training technician. Each dosimeter ring has a unique ID and is assigned to a specific person. 

The Tracer 5 pXRF can be run either independently or through an attached pc laptop. The Bruker RemoteCTRL software on the laptop mirrors what is present on the screen of the Tracer5 and all functions are the same. If the connection between the device and the laptop is interrupted, there is no loss of data.

Note: The batteries cannot be 'hot swapped'. If a battery is running low, either shut off the Tracer, switch batteries and power it back on again, or plug the AC power in, change the battery, and then unplug the device again.

Sample Preparation

Preparing section halves

Preparing powdered samples

Sample Measurement Set Up

Shielded holder for section halves

Desktop stand

Benchtop Chamber

Instrument Set Up

Begin by installing a fully charged battery or powering the device using an AC power adaptor. The Tracer 5 can be operated alone or connected to a laptop. Using Bruker RemoteCTRL , the device screen is mirrored on the laptop. They type of sample you are measuring or your chosen measurement set up. 

Computer connection

Application and Settings

The current application can be changed by selecting , choosing a different application type and selecting ‘OK’. This device has 5 applications installed (See Appendix for details). The best application for our purposes is GeoExploration. Each application has different scanning parameters which preferentially pick up some elements better than others. The device will keep the chosen application until manually changed.

Some application settings, such as beam scan duration, can be adjusted by selecting on the main display screen. Three settings can be adjusted (Fig. 1):

• Duration: This screen will display the number of phases used by the current application. The time in seconds spent on each phase can be adjusted or set to unlimited (ending when the trigger is released). Note: The longer the scan time, the greater the accuracy and precision and the lower the error. For geological samples, 1 minute per phase or longer is not uncommon, but not required.
• First Result/Test: This is the number of seconds before results will be shown on the display once a measurement has been triggered.
• Trigger Active: The trigger can be set to ‘Auto’ or ‘Manual’ by selecting this button.
  • Auto: The measurement proceeds by pressing and releasing the trigger. Preferred.
  • Manual: The trigger must be pressed for the duration of the measurement. If the trigger is released at any time during the measurement, measuring will stop.

Figure 1. Settings display screen.

Select ‘Ok’ when finished adjusting or 'Cancel' to return to the previous screen.

Making a Measurement

Edit Sample Information

On the main display, click the ‘Edit Info’ button in the middle of the bottom row of buttons. This screen (Figure 4) is where the sample information is entered. All fields in the right column are editable by double clicking and should be reviewed and changed for each sample:

• Sample Type:
  • Standard – a powdered standard in a sample cup
  • SHLF – a measurement taken directly on a section half or of a piece from a section half
  • Sample – a powdered sample in a sample cup
  • Discrete – for any other samples
• Expedition: The current expedition, example 397.
• Site and Hole: The site and hole the sample was taken from, example: U1586A.
• Core/Section: The core number with letter indicating the core type and the section in that core that is being measured or that the sample was taken from, example: 1H/6. If measuring a standard, enter the standard name, example: BCR 2 or BHVO 2.
• TextID: The unique sample number for every sample. This is found on the lower right corner of the typical sample label, example: SHLF11754181. Note: If the device is connected to the laptop and using Bruker RemoteCtrl software, use the scanner to enter the TextID. If measuring a standard, use the information from the appropriate QAQC label provided. If a standard does not have a QAQC label, leave this field blank.
• Top Offset (cm):
  • For a section half or sample from a section half (discrete, unaltered piece), this is the distance from the top of the core section, example: 34 or 101.5 (Do not put a range, just the beginning number of the measured area or sample).
  • For powdered samples and standards, use 0.
• Comment: Use this to provide any additional information, such as a physical description for reference or to indicate a replicate measurement.

Figure 5. The Edit Info display screen.

Select 'OK' in the lower left corner of the screen. The display will return to the main display screen. Once a measurement is complete, if you edit any sample information, the sample run number will advance.

Execute a Scan

There are 2 ways to initiate a scan:

If the device is connected to the laptop select ‘Trigger Pull (F6)’ along the top of the RemoteCtrl program window or press F6. The measurement will begin and continue until finished. Note: If the device is moved away from the sample, the measurement will stop!

If you are not connected the laptop press the device to the sample, the proximity sensor will detect a sample and the device will be armed for measurement. Press and release the trigger. The measurement will begin and continue until finished. Note: If the device is moved away from the sample, the measurement will stop!

A beep will sound when the device has finished measuring and the device can be moved away from the sample or repositioned for the next measurement. At this point, the previous measurement’s data has been stored and added to the results file.

The Tracer updates the ‘Data’ folder after each new measurement with an associated .pdz file and also adds the data to the appropriate application .tsv file and .csv ‘Results’ file. Highlight the files you want to download and then select the ‘Download’ option in the toolbar of the program window. A smaller window will appear and here you can select the location you wish to download the files to. Download all data files (.tsv, .csv, and .pdz) to C:\DATA\IN. The .tsv and .csv files will have all measurements that have been taken since the most recent internal memory clean-up, which will typically be done after each site or more frequently depending on the number of measurements executed. After further measurements, downloading again will add only the new measurements, but will replace the .tsv and .csv files with updated versions that will include the new measurements. 

Login to the computer using the login information on top of the computer keyboard.

First, turn on the instrument. To do this press the button on top of the device screen and hold it for a few seconds (Figure 1).

Figure 1. Bruker pXRF Handheld instrument

Click on Bruker RemoteCtrl in the computer screen (Figure 2). You will use this program to control the device from the computer while measuring your samples. 

Figure 2. Bruker Remote Ctrl program

Go to File Connect. A window will appear that will show the device number Ex.  900G7838. Select it  and click Ok (Figure 3).

Figure 3. Connecting the device to the computer.

A login window will appear on the screen, login using the info on top of the computer keyboard (Figure 4).

Figure 4. Login screen in Bruker Remote Control

A pop up message will appear after logging in that tells you the gun's configuration just click OK (Figure 5).

Figure 5. Configuration window when initializing the device.

When the device is connected, your screen should look like Figure 6. The device will say Not Armed when the x-ray is not armed and the device will say Ready to Test when the x-ray is active.

Figure 6. pXRF initial screen. Left: X-ray is not active. Right: X-ray is active

Downloading Data

Click on   in the bottom left of the main screen. After you click on Utilities the following window will appear on the screen (Figure 7). 

Figure 7. Utilities Window.

IMPORTANT: Never select Move as that will move the data from the internal memory into the computer, therefore deleting it from the device. 

Figure 8. Backup Data. 

After you have selected the file destination folder click on 

Close Bruker RemoteCtrl.

Bruker Instrument Tools

After you backup the data go to Bruker Instrument Tools icon in the computer's initial window (Figure 9).

Figure 9. Bruker Instrument Tools program

Figure 10. Connect the device to Bruker Instrument Tools.

Go to Device  Connect   Select 900G7838   and click Connect (Figure 10 & Figure 11).

Figure 11. Connect window.

After you are connected in Bruker instrument tools on the left side of the screen you will see a folder that says ARCHIVE

Open the ARCHIVE folder and you will see a screen like figure 12.

Figure 12. Archive folder

Go to Data  Open the most recent backup (Figure 13).

Figure 13. Data folder 

Select the file called GeoExploration.tsv (Figure 14)

Figure 14. GeoExploration file inside the backup folder.

Copy the GeoExploration.tsv file by right-clicking the file name and selecting copy from the dropdown menu. 

Without exiting the program find the folder you want to place the data in the bottom window (Figure 15).

After you find the folder right-click the selected folder and select Paste  from the dropdown menu.                  

Figure 15. Copy GeoExploration file and paste in to a folder in Windows(C:/)

Opening the file in Excel

Open a new workbook and go to the Data tab and select  (Figure 16).

Figure 16. Excel Data window → Select From Text in the left.

You will be prompted to your computer saved folders and you can select the folder where you saved the GeoExploration.tsv file.

Once you find the folder select All Files in the bottom right (Figure 17).

Then select the GeoExploration.tsv file and click Import. (Figure 17).

Figure 17. Finding the GeoExploration file

A window will open showing you a preview of the file and you have to click Load. (Figure 18)

Figure 18. Data Preview

Click load and the data will be exported to excel and should look like Figure 19.

Figure 19. Exported file from pXRF device.

Setting Date & Time

Note: If the device is powered off for a significant period of time, it is possible for the internal battery to discharge. The only affect of this will be that the date and time are reset. If the device has not been used for an expedition, check that the date and time are correct before proceeding to measurements.

To set the time, select on the main display screen. Then select and then select Date/Time from the available list. A stylus or fine pointed tool (non-metal, such as a wooden applicator stick) is helpful to access the small buttons involved in setting the date and time.

In the screen that displays (Fig. XX), change the date by selecting on year, month and the numerical day. The time can be changed by using the selecting the hour, minute, second and AM/PM and using the small arrows to the right of the box to adjust the number. Please set the device to UTC time (NOT the same as ship operation time). If unsure what UTC time is, check the time on the nearest lab computer.

Once the correct date and time is shown (as close as possible), select ‘Apply’ and then ‘OK’ to exit the screen.

Figure XX. The date and time setup screen.

Appendix

Application Calibration Information

GeoExploration/GeoMining

Limestone

Precious Metals 2

Mudrock 2 Air

Mudrock 2 He

LIMS Component Table

ARCHIVE

LN-BrukerpXRFHandheld-270922-1259-68.pdf - September 27, 2022