Bruker M1 MISTRAL User manual

M1 ORA
M1 MISTRAL
Micro-XRF Benchtop Spectrometer
User Manual

Bruker Nano GmbH
Am Studio 2D
12489 Berlin
Tel. [phone]
Fax [phone]
E-Mail [email protected]
Internet www.bruker.com
The reproduction, transmission or use of this document or its contents is not permitted
without express written authority. Offenders will be liable for damages. All rights reserved.
We have checked the contents of this manual for agreement with the hardware and
software described. Since deviations cannot be precluded entirely, we cannot guarantee full
agreement. However, the data in this manual are reviewed regularly and any necessary
corrections are included in subsequent editions. Suggestions for improvement are welcome.
Order no. DOC-M81-EXX024. Issue: 07/07/15
©2015 Bruker Nano GmbH, Berlin.
All trademarks and registered trademarks are the sole property of their respective owners.
Printed in the Federal Republic of Germany.

Contents
M1 ORA/MISTRAL 3
Contents
1Introduction.................................................................................................................................9
1.1 About this Manual ..........................................................................................................9
1.2 User Information ............................................................................................................9
1.3 Intended Usage ...........................................................................................................10
1.4 Warranty and Liability ..................................................................................................11
2Safety Instructions ...................................................................................................................12
2.1 Basic Safety Requirements .........................................................................................12
2.2 Safety Requirements on the Place of Installation........................................................13
2.3 Radiation Protection ....................................................................................................13
2.4 Protection from Electric Current ..................................................................................14
2.5 Staff Requirements ......................................................................................................15
2.6 Safety Equipment ........................................................................................................15
2.7 Name Plates and Warning Labels ...............................................................................17
3Functional Principles ...............................................................................................................18
3.1 Physical Background of X-ray Generation...................................................................18
3.1.1 X-ray Fluorescence ......................................................................................18
3.1.2 Bremsstrahlung ............................................................................................19
3.2 Detection of X-ray Quanta ...........................................................................................20
3.3 Digitalization and Channel Allocation ..........................................................................21
3.4 Spectrometer Resolution .............................................................................................22
3.5 Composition of a Spectrum .........................................................................................24
3.6 Evaluation of X-ray Fluorescence Spectra ..................................................................25
4The M1 ORA/MISTRAL System ...............................................................................................28
4.1 Product Description .....................................................................................................28
4.2 Product Versions .........................................................................................................28
4.2.1 M1 ORA........................................................................................................28
4.2.2 M1 MISTRAL................................................................................................29
4.3 Hardware System Components...................................................................................30
4.4 Technical Parameters..................................................................................................31
4.5 Hardware Installation ...................................................................................................33
4.5.1 Room Planning.............................................................................................33
4.5.2 Electrical Connection....................................................................................33
4.5.3 External Requirements.................................................................................34
4.6 Software.......................................................................................................................34
4.6.1 Software Description ....................................................................................34
4.6.2 Program Installation .....................................................................................35
4.6.3 Installation of Drivers....................................................................................40
4.6.4 Configuration Files .......................................................................................43
4.7 Establishing the Operational State ..............................................................................43
5Using the XSpect Pro Program ...............................................................................................46
5.1 XSpect Pro Program Start-up ......................................................................................46
5.2 Display and Control Elements .....................................................................................48
5.2.1 Instrument Status Bar...................................................................................48
5.2.2 Navigation Bar..............................................................................................48
5.2.3 Print Report/ Additional Information .............................................................49
5.3 Stage Control and Video Settings ...............................................................................50
5.3.1 Manual Z Stage ............................................................................................50
5.3.2 Motorized Z Stage ........................................................................................50
5.3.3 Motorized X-Y-Z stage .................................................................................51
5.3.4 Easy Load ....................................................................................................52
5.3.5 Video Settings ..............................................................................................52

Contents
4User Manual
5.4 System Spectra Measurements.................................................................................. 54
5.4.1 Measuring Reference Spectra..................................................................... 54
5.4.2 Measuring Pure Element Spectra................................................................ 55
5.4.3 Measuring Primary Spectra ......................................................................... 56
5.4.4 Measuring Standard Spectra....................................................................... 57
5.5 Sample Measurement ................................................................................................. 59
5.5.1 Measurement Methods ................................................................................ 61
5.5.2 Keyboard Shortcuts ..................................................................................... 62
5.5.3 Result Tab ................................................................................................... 62
5.5.4 Table Tab..................................................................................................... 63
5.5.5 Trend Tab .................................................................................................... 64
5.5.6 Spectrum Tab .............................................................................................. 65
5.5.7 Touch Screen User Interface....................................................................... 67
5.6 Stage Program Workspace......................................................................................... 69
5.6.1 Load/Create Stage Programs...................................................................... 70
5.6.2 Graphic Display of Measurement Points ..................................................... 71
5.6.3 Reference Points Table ............................................................................... 71
5.6.4 Measure Points Table.................................................................................. 72
5.6.5 Create/Edit Stage Programs........................................................................ 72
6Using the XData Program........................................................................................................ 75
6.1 XData Program Start-up.............................................................................................. 75
6.2 Display and Control Elements..................................................................................... 75
6.3 Managing Standards ................................................................................................... 77
6.3.1 Saving a List of Standards........................................................................... 78
6.3.2 Loading a List of Standards......................................................................... 78
6.3.3 Editing Basic Data ....................................................................................... 78
6.3.4 Creating New Standards.............................................................................. 79
6.4 Managing Methods...................................................................................................... 80
6.4.1 Creating a Method ....................................................................................... 81
6.5 Managing System Spectra........................................................................................ 103
6.5.1 Adding Spectra to the Database................................................................ 104
6.5.2 Delete a Spectrum from the Database ...................................................... 104
6.6 System Settings ........................................................................................................ 105
6.7 Managing the Database ............................................................................................ 105
6.7.1 Report Templates ...................................................................................... 105
6.7.2 Integrity ...................................................................................................... 107
6.7.3 Data Processing ........................................................................................ 107
7Shutdown................................................................................................................................ 110
7.1 Switching off the Instrument...................................................................................... 110
7.2 Standby Mode ........................................................................................................... 110
8Maintenance of the M1 ORA/MISTRAL ................................................................................ 111
8.1 Fuse Replacement .................................................................................................... 111
8.2 Cleaning the Sample Chamber................................................................................ 112
9Transportation........................................................................................................................ 113
10 Disposal .................................................................................................................................. 114
AStandard Delivery Contents.................................................................................................. 115
BGeneral Safety Precautions .................................................................................................. 116
CBiological Effects of X-ray Radiation ................................................................................... 117
Index.............................................................................................................................................. 119

Table of Figures
M1 ORA/MISTRAL 5
Table of Figures
Fig. 1 Safety equipment on the front panel of the M1 ORA/MISTRAL.............................. 16
Fig. 2 Schematic visualization of the X-ray fluorescence process in an atom .................. 18
Fig. 3 Schematic working principle of a silicon drift detector (SDD).................................. 21
Fig. 4 Origin of a X-ray fluorescence spectrum ................................................................. 22
Fig. 5 Fitting process with two Gaussian shaped profiles ................................................. 23
Fig. 6 Definition of the full width at half maximum (FWHM) .............................................. 24
Fig. 7 Typical XRF spectra of glass, precious metal alloy and steel ................................. 24
Fig. 8 M1 ORA with computer ........................................................................................... 29
Fig. 9 M1 MISTRAL with computer.................................................................................... 29
Fig. 10 Main components of the M1 ORA/MISTRAL........................................................... 30
Fig. 11 Room planning for the installation of the M1 ORA/MISTRAL ................................. 33
Fig. 12 „Run as administrator“ option for program installation ............................................ 35
Fig. 13 Select setup language. ............................................................................................ 36
Fig. 14 Select type of installation......................................................................................... 36
Fig. 15 Select folder for installation ..................................................................................... 37
Fig. 16 Select data folder..................................................................................................... 37
Fig. 17 Select components for installation........................................................................... 38
Fig. 18 Installation of the video driver software ................................................................... 38
Fig. 19 Installation of Acrobat Reader ................................................................................. 39
Fig. 20 Installation of XML Notepad .................................................................................... 39
Fig. 21 Restart of the computer and creation of a new XSpect Pro database .................... 40
Fig. 22 Windows Device manager after connecting the M1 ORA/MISTRAL ...................... 41
Fig. 23 Properties dialog for the M1 ORA/MISTRAL before installing the correct driver .... 41
Fig. 24 Setting the driver path manually for the unknown devices...................................... 42
Fig. 25 Windows security warning during driver installation................................................ 42
Fig. 26 Finishing the successful instrument driver installation ............................................ 42
Fig. 27 Status display during initialization of the XSpect Pro program................................ 46
Fig. 28 Switching on the high voltage.................................................................................. 46
Fig. 29 Main screen of the XSpect Pro program ................................................................. 47
Fig. 30 Additional information dialog ................................................................................... 49
Fig. 31 Stage control for the manual Z stage ...................................................................... 50
Fig. 32 Stage control for the motorized Z stage .................................................................. 50
Fig. 33 Stage control for the motorized X-Y-Z stage ........................................................... 51
Fig. 34 Cross hair parameters dialog .................................................................................. 52
Fig. 35 Video settings dialog ............................................................................................... 53
Fig. 36 Save dialog .............................................................................................................. 53
Fig. 37 Main screen of the System spectra workspace....................................................... 54
Fig. 38 Recording reference spectra ................................................................................... 55
Fig. 39 Recording pure element spectra ............................................................................. 56
Fig. 40 Recording primary spectra ...................................................................................... 57
Fig. 41 Recording standard sample spectra........................................................................ 58
Fig. 42 Measurement workspace ........................................................................................ 59
Fig. 43 Selection of an existing measurement method ....................................................... 61
Fig. 44 Pre-examination tab ................................................................................................ 62
Fig. 45 Measurement workspace - Results tab ................................................................... 63
Fig. 46 Measurement workspace - Table tab ...................................................................... 63
Fig. 47 Measurement workspace - Trend tab...................................................................... 64
Fig. 48 Measurement workspace – Spectrum tab............................................................... 65
Fig. 49 Touch screen user interface .................................................................................... 68
Fig. 50 Stage program screen ............................................................................................. 69
Fig. 51 Selection or creation of a stage program ................................................................ 70
Fig. 52 Graphic display of the stage program ..................................................................... 71
Fig. 53 Table of measurement positions ............................................................................. 72
Fig. 54 Create/edit a stage program.................................................................................... 73
Fig. 55 Status display during initialization of the XData program........................................ 75
Fig. 56 Start-up screen of the XData program .................................................................... 76
Fig. 57 Standards workspace .............................................................................................. 77

Table of Figures
6User Manual
Fig. 58 List of files needed to save a list of standards ......................................................... 78
Fig. 59 Basic data editor ...................................................................................................... 79
Fig. 60 Sample editor ........................................................................................................... 79
Fig. 61 Methods workspace ................................................................................................. 81
Fig. 62 Method editor – Structure tab .................................................................................. 82
Fig. 63 Element properties editor......................................................................................... 83
Fig. 64 Method editor – Normation tab ................................................................................ 85
Fig. 65 Method editor – Calibration tab without added standards ....................................... 86
Fig. 66 The available samples dialog................................................................................... 86
Fig. 67 Method editor – Calibration tab with added standards before calibration................ 87
Fig. 68 Method editor – Calibration tab after calibration ...................................................... 87
Fig. 69 Method calibration with several calibration ranges .................................................. 88
Fig. 70 Method calibration tab with highlighted outlier......................................................... 89
Fig. 71 Method editor – Structure tab .................................................................................. 90
Fig. 72 Element properties editor......................................................................................... 91
Fig. 73 Method editor – Normation tab ................................................................................ 92
Fig. 74 Method editor – Calibration tab without added standards ....................................... 93
Fig. 75 The available samples dialog................................................................................... 93
Fig. 76 Method editor – Calibration tab with added standards before FP calculation ......... 94
Fig. 77 Method editor – Calibration tab after FP calculation, but before calibration............ 94
Fig. 78 Method editor – Calibration tab after first calibration ............................................... 95
Fig. 79 Method editor – Structure tab .................................................................................. 96
Fig. 80 Element properties editor......................................................................................... 97
Fig. 81 Method editor – Normation tab ................................................................................ 98
Fig. 82 Method editor – Calibration tab without added standards ....................................... 99
Fig. 83 The available samples dialog................................................................................... 99
Fig. 84 Method editor – Calibration tab with added standards before FP calculation ....... 100
Fig. 85 Method editor – Calibration tab after FP calculation, but before calibration.......... 101
Fig. 86 Method editor – Calibration tab after first calibration ............................................. 102
Fig. 87 Spectra workspace ................................................................................................ 103
Fig. 88 Adding spectra to the database ............................................................................. 104
Fig. 89 Report templates tab.............................................................................................. 105
Fig. 90 Report editor .......................................................................................................... 106
Fig. 91 Data processing – Selection tab ............................................................................ 108
Fig. 92 Data processing – Results tab ............................................................................... 109

List of Tables
M1 ORA/MISTRAL 7
List of Tables
Table 1 Safety equipment of the M1 ORA/MISTRAL ........................................................... 15
Table 2 Name plates and warning labels on the M1 ORA/MISTRAL instrument................. 17
Table 3 Steps during spectrum evaluation ........................................................................... 25
Table 4 Connections of the M1 ORA/MISTRAL system components.................................. 30
Table 5 Technical parameters of the M1 ORA/MISTRAL .................................................... 31
Table 6 Specifications for the electrical connections............................................................ 33
Table 7 External installation requirements ........................................................................... 34
Table 8 Steps for the instrument start-up ............................................................................. 43
Table 9 Displays in the instrument status bar....................................................................... 48
Table 10 Functions in the XSpect Pro navigation bar ............................................................ 48
Table 11 Functions for the stage movement .......................................................................... 51
Table 12 Functions in the main panel for measurements with XSpect Pro............................ 59
Table 13 Keyboard shortcuts.................................................................................................. 62
Table 14 Display options in the spectrum tab......................................................................... 66
Table 15 Peak identification.................................................................................................... 67
Table 16 Control elements in the touch screen mode............................................................ 68
Table 17 Main functions in the stage program workspace ..................................................... 70
Table 18 Options for selected single entries in the measure points table.............................. 73
Table 19 Options for selected multiple entries in the measure points table........................... 74
Table 20 Functions in the navigation bar of XData ................................................................ 76
Table 21 Settings in the element properties editor................................................................. 83
Table 22 Fuse replacement.................................................................................................. 111
Table 23 Standard delivery contents of the M1 ORA/ MISTRAL ......................................... 115

Introduction
M1 ORA/MISTRAL 9
1 Introduction
1.1 About this Manual
This manual is intended to familiarize the user with the operation of the X-ray analytical instrument
M1 ORA/MISTRAL in the executions manually and automatic developed by Bruker Nano GmbH.
This manual allows you to get started quickly as it includes all information necessary to operate the
instrument safely and competently.
These instructions cover functionality, configuration and operation of the M1 ORA/MISTRAL
hardware. They are considered as part of the device and must be kept at hand near the product.
Sections 4.2 and 4.3 provide an overview of the M1 ORA/MISTRAL instrument versions and
product components. Refer to chapter 5 and 6 for all information necessary to operate the
M1 ORA/MISTRAL control software programs XSpect Pro and XData.
A solid understanding of these instructions is mandatory for the operation of the M1 ORA/MISTRAL
instrument by Bruker Nano GmbH. Please, familiarize yourself with the contents and follow the
safety instructions, particularly those regarding the handling of the product. This way you can be
sure of taking full advantage of the product’s capabilities.
Bruker Nano GmbH reserves the right to make product modifications, which enhance technical
advancement.
1.2 User Information
The manual is divided up sections and appendices. On each page, you can find the section
heading in the header. The footer contains the manual’s document status with the indication of the
date of issue and the page number.
Various cross-references are included in the operating instructions to ease navigation within the
document and to change to external documentation.
The following warning symbols and informational symbols as well as signal words are used in this
operating instruction:
Danger!
Warning of a potential danger to life and limb.
Danger!
Warning of a potential danger to life and limb from electrical current.
Danger!
Warning of a potential danger to life and limb from X-ray radiation.
Danger!
Warning of a potential danger to life and limb from exposure to toxic materials.

Introduction
10 User Manual
Caution!
Warning of possible material damage or damage to machinery.
Note
Tips on usage and useful information.
Note
Information on protecting the environment.
1.3 Intended Usage
The X-ray spectrometers M1 ORA/MISTRAL by Bruker Nano GmbH may solely be used for
material analysis, in particular for the determination of element composition of materials as well as
analysis of layered sample systems with respect to thickness determination and layer composition.
Any other use beyond that described is considered as non-intended usage. The operator, not the
manufacturer, assumes sole liability for all personal injury and material damage arising from non-
intended usage.
The following applications are explicitly excluded from the definition of intended usage:
Any sort of medical and biological application
Radiographic applications
Online process control for industrial or research purposes
Analysis of radioactive or chemically aggressive substances
The M1 ORA/MISTRAL instruments may solely be operated by trained and authorized staff and
only in compliance with all safety instructions covered in this manual. A safe and accurate
operation cannot be guaranteed unless the instrument is properly used as defined within these
operating instructions.
The intended usage requires the following:
The presence of at least one person designated to be responsible during operation. This
person has to be trained by the manufacturer in the handling of the instrument or was
instructed by a person trained by the manufacturer.
Basic knowledge about the software packages of “XSpect Pro“ and “XData”.

Introduction
M1 ORA/MISTRAL 11
1.4 Warranty and Liability
The general conditions of sale and supply devote to the operator of the M1 ORA/MISTRAL
instruments upon delivery by Bruker Nano GmbH. Warranty and liability claims for personnel and
material damage are excluded if they are a result of any of the following reasons:
Improper use of the M1 ORA/MISTRAL
Improper start-up, installation, transport or operation of the M1 ORA/MISTRAL
Non-compliance of the external operation conditions such as temperature, humidity,
vibrations, aggressive chemical substances etc.
Structural modifications to the M1 ORA/MISTRAL
Operation of the M1 ORA/MISTRAL while the protective housing is not completely closed or
damaged
Operation of the M1 ORA/MISTRAL while the safety circuits are not working properly or are
willingly bypassed
Disregarding of the safety regulations and instructions listed in this manual
An improper connection and improper cabling of the M1 ORA/MISTRAL and of its safety
equipment
Use of a control software other than “XSpect Pro“ included in the delivery
Use of a computer technology other than that included in the delivery or a different
measurement computer than the one acknowledged by the manufacturer.

Safety Instructions
12 User Manual
2 Safety Instructions
X-ray energy levels (up to 50 keV) of the excitation beam as used for excitation in the
M1 ORA/MISTRAL cause damage to tissue and bone if exposed to it directly. As a result, poorly
healing wounds and, in extreme cases, loss of individual limbs (e.g. fingers) could occur.
Other than radiation damages caused by an accidental exposure to high dosages of radiation over
short time, so-called nondeterministic damages, such as increased risk of cancer, can be a result
of exposure to lower radiation doses over a prolonged period of time.
All information pertaining to safety in this document applies to current, valid, national laws and the
Ordinance of the European Union. In other countries, applicable laws and national regulations must
be complied with.
In addition to the safety instructions in this document, general, valid, regulations regarding accident
prevention and the protection of the environment must also be observed and complied with. All
information in these operating instructions must be followed unreservedly at all times.
In order to safely operate X-ray machines such as the M1 ORA/MISTRAL, norms, directives and
regulations are defined for safety and radiation protection. These must strictly be adhered to by
both manufacturer and users.
2.1 Basic Safety Requirements
The following basic safety requirements must be observed at any times:
The M1 ORA/MISTRAL may only be used as intended.
All safety instructions in this document and in all other applicable documents must be
observed and fulfilled.
The device may not be operated unless the complete safety equipment, such as the
protective housing, is present and fully functional.
Each person who is authorized to set up, install, activate or operate the M1 ORA/MISTRAL
must have read and understood the complete manual.
The operating instructions must be available to the user at any time.
Smoking, eating and drinking near the machine is not allowed.
Operation is not allowed in case of fatigue as well as under the influence of alcohol or drugs.
The operating staff must be in good physical and psychological condition to avoid impairment
of judgment either temporarily or permanently.
Only authorized service staff is allowed to perform maintenance work on the
M1 ORA/MISTRAL. Excluded are maintenance works, which have explicitly been allowed to
the user.
Operating the instrument (i.e. switching on the high voltage supply of the X-ray tube and/or
opening the beam shutter) is only allowed by using the XSpect Pro software.

Safety Instructions
M1 ORA/MISTRAL 13
2.2 Safety Requirements on the Place of Installation
Caution!
The M1 ORA/MISTRAL spectrometers weigh 24 kg, respectively 46 kg.
Dropping the instrument can cause injuries or lead to damage of the device
and subsequent failure.
The following safety measures must be observed when installing the instrument:
The instrument and the control computer must be placed on a stable and fixed support. A
trolly is not suitable as measuring site.
The measurement site must not be exposed to intensive vibrations.
The measurement site must not be close to strong magnetic fields such as electric motors or
generators.
The instrument is designed for indoor use. In the surrounding of the measurement site, there
must not be any sources of splashing water such as showers or washing sites.
The instrument must not be exposed to aggressive media at the measurement site.
The installation site of the instrument must only be accessible to authorized staff or must be
monitored.
Furthermore, the parameters defined in the technical specification respectively the installation
guide apply to the installation site.
2.3 Radiation Protection
Danger!
Without the manufacturer’s radiation protection measures the X-ray source
used in this instrument constitutes a health risk.
A direct exposure to the excitation beam for several seconds could cause a deep damage of
biological tissue. Contrary to such a radiation injury with a high dose over a short period, a lower
radiation exposure over a long period could increase the risk of cancer.
Observing the safety rules can prevent a risk of X-ray radiation for the operator due to the
measures taken and the technical installations provided by the manufacturer.
According to the Röntgenverordnung (RöV) – the German X-ray Ordinance – the
M1 ORA/MISTRAL complies with a full protection system (Appendix III RöV) regarding its radiation
protection data and the radiation exposure of the operating staff.
Among others, the following safety measures were taken with the construction of the
M1 ORA/MISTRAL:
The X-ray source is completely encapsulated by a safety housing.
At no point at a distance of 10 cm to any accessible part of the instrument the local dose rate
excels 1.5 µSv/h.
All safety relevant functions are controlled by hardware and software independently.
All safety relevant control functions are implemented redundantly.
All safety circuits are wire-bound.
System voltage can be switched on only by using a key switch.
High voltage can be switched on only via the “XSpect Pro” control software.

Safety Instructions
14 User Manual
The following basic safety rules must be observed at any time:
It is strictly prohibited to modify or remove parts of the system housing or to open the
instrument.
It is prohibited to operate the instrument when parts of the housing or other components of
the instrument appear to be seriously damaged (e.g. transport accident).
The M1 ORA/MISTRAL may only be operated with the delivered control software
„XSpect Pro“. Only by using this software the operation parameters of the X-ray source can
be guaranteed to comply with anti-radiation precautions, as certified.
2.4 Protection from Electric Current
Danger!
The mains voltage supply of 100 V to 240 V and the high voltage supply of the
X-ray tube of 50 000 V are perilous upon physical contact.
Observing the safety rules can prevent bodily injuries of the operator due to the measures taken
and the technical installations provided by the manufacturer.
The same basic safety rules (refer to section 2.1) are valid both for the prevention of damages to
persons by electric current and for the prevention of damages by X-ray radiation.
The following safety rules have to be considered additionally:
The power supply of the instrument installation site must have a ground conductor contact.
Only the power and signal cables included in delivery have to be used for the operation of the
instrument. They must be undamaged.
Especially after transport, the instrument must not be operated unless it is acclimatized to
room temperature and no water condensed on or inside the instrument.
It is prohibited to operate the instrument if the ambient relative humidity would result in the
condensation of water on parts of the instrument.
It is prohibited to take the instrument into operation if accidentally water was spilled on or into
the instrument.

Safety Instructions
M1 ORA/MISTRAL 15
2.5 Staff Requirements
The following requirements are made relating to the operating staff of the M1 ORA/MISTRAL:
In case of fatigue as well as under the influence of alcohol or drugs operating the instrument
is not allowed. The operating staff must not have any physical or emotional restrictions that
impair the attention or judgment either temporarily or permanently.
At least one person of the operating staff must have been familiarized by the manufacturer
with the technical and safe operation of the M1 ORA/MISTRAL. This accountability is non-
transferable.
Each person who is authorized to set up, install, activate or operate the M1 ORA/MISTRAL
must have read and understood the complete manual.
The staff must have sufficient knowledge of the following operational procedures, regulations,
behaviour and components:
Operational procedures such as starting up and shut down the M1 ORA/MISTRAL.
Safety equipment of the M1 ORA/MISTRAL and its correct function.
Operational procedures during the operation of the instrument.
Behavior and actions to be taken in hazardous situations.
2.6 Safety Equipment
Danger!
The M1 ORA/MISTRAL must only be operated with functional safety
equipment.
In the M1 ORA/MISTRAL, X-ray radiation with a maximum energy of 50 keV is generated with a
maximum tube rating of 50 W (refer also to the datasheet of the X-ray tube). All possible
constructive measures have been implemented to avoid X-ray radiation hazards for the operating
personnel.
The M1 ORA/MISTRAL is equipped with the safety equipment compiled in Table 1 and illustrated
in Fig. 1.
Table 1 Safety equipment of the M1 ORA/MISTRAL
Pos. Safety equipment Function
1 Key switch Implies an operation by authorized persons only
2 Warning light “Power” (green) Indicates that the mains voltage is switched on and the
instrument can be taken into operation
3 Warning light “X-ray on” (yellow) Indicates that the beam shutter is opened and X-rays from
the X-ray tube are emitted into the sample chamber. If this
indicator has a malfunction, the high voltage is switched
off and cannot be switched on.
4 Warning light “HV on” (red) Indicates that the X-ray tubes high voltage supply is
switched on and radiation is produced inside the X-ray
tube.

Safety Instructions
16 User Manual
Pos. Safety equipment Function
5 Instrument door with door
switches
Door switches connected to the safety circuitry ensure
that the beam shutter is closed immediately if the
instruments door is opened.
6 Primary radiation protection of
the X-ray tube
Housing made of 6 mm thick brass with a 3 mm wide
opening for limiting the beam emission
7 Beam shutter Software-controlled beam shutter opened only for the time
of the measurement and only with closed instrument door
to minimize the time period of emitting X-rays.
8 Internal safety switches Interlock circuit connected with the housing parts inside
the instrument. Opening the instrument for service
purposes will lead to an interruption of HV or even the
24 V power supply.
1 2 3 4 5 2 3 4 5
Fig. 1 Safety equipment on the front panel of the M1 ORA/MISTRAL
The key switch (1) for the M1 MISTRAL is located on the front panel and for the M1 ORA it can be
found at the back side close to the mains power supply connector. The safety equipment parts 2, 3,
and 4 are located on the front panel of the instrument (see Fig. 1). The safety equipment 6, 7 and 8
are located inside the instrument and can just be monitored and maintained by authorized service
staff.

Safety Instructions
M1 ORA/MISTRAL 17
2.7 Name Plates and Warning Labels
Table 2 Name plates and warning labels on the M1 ORA/MISTRAL instrument
Element Location Function
Front panel Company logo
Front panel Product name
Rear panel Name plate of the instrument
Rear panel Warning label of the X-ray source and the
HV generator

Functional Principles
18 User Manual
3 Functional Principles
This section offers a short overview over the basic physics of Micro-XRF and the functional
principles of some of the components of the M1 ORA/MISTRAL.
3.1 Physical Background of X-ray Generation
In the electromagnetic spectrum X-radiation is found between the ultraviolet regime and γ-radiation.
Even though there is no clear threshold between these spectral ranges, usually X-rays are
assigned the regime from 10 nm to 0.01 nm. These wavelengths correspond roughly to photon
energies from 100 eV to 100 keV. With e denoting the elementary charge of 1.602 10-19 As, the
value of 1 eV corresponds to 1.602 10-19 VAs (= 1.602 10-19 J). Electronvolts (eV) is the
conventional unit for denoting energies of X-ray photons.
There are two distinct physical processes in which X-rays are produced. Both will shortly be
explained in the following section. The first process is the fluorescence process giving rise to the
characteristic X-ray line spectrum. The second leads to a continuous spectrum, the so-called
bremsstrahlung radiation.
3.1.1 X-ray Fluorescence
In atomic physics, fluorescence generally is defined as a two-stage process. At first an atom is
transferred to an excited state by an external energy transfer. In the second step the atom quickly
relaxes back into the initial state and in the process a fluorescence photon is spontaneously
emitted.
Excitation and relaxation of atoms express themselves as changes in the electron shell. In a
simplified picture this electron shell is formed by circular orbits concentric around the nucleus,
where electrons with higher binding energy have their orbits on the inner shells. In this picture the
quantified binding energies of the electrons are visualized by the discrete radii of the orbits.
The initial energy transfer of the fluorescence process can take place either by a collision with a
particle (protons, other ions or electrons) or, as is the case for X-ray fluorescence (XRF), by
interaction with a high-energy photon.
Fig. 2 Schematic visualization of the X-ray fluorescence process in an atom

Functional Principles
M1 ORA/MISTRAL 19
Characteristics of X-ray fluorescence include:
Electrons that change between two orbits can do so only by absorbing or emitting specified
quanta of energy which correspond to the binding energy difference between the two shells.
Every single kind of atom, i.e. each individual element, has its own set of allowed radii of
electron orbits. Therewith the energy differences and as a result the energies of the emitted
X-ray photons are element specific.
The electron orbits are labeled K-, L-, M-, etc. shells. Depending on the primarily ionized shell
the emitted X-rays are usually also labeled K-, L-, and M-radiation. To designate the shell
from which the secondary electron which filled the vacancy originated, additional labels are
assigned to the fluorescence lines, e.g K1,2, K1 or L. For historic reasons this
labeling is based rather on intensity of the fluorescence line than on a consistent scheme. For
a systematic nomenclature please refer to the IUPAC notation.
The energy of the excitation photon needs to be sufficient to ionize the atom. This amount of
energy initially transferred is always larger than the energy set free during any inner-atomic
relaxation process. Therefore the photon energy needed to excite characteristic
radiation is always higher than the fluorescence line energy itself. For example, only
photons with energies above 11.92 keV can excite Au Lradiation at 9.7 keV.
3.1.2 Bremsstrahlung
Whenever the velocity of a charged particle is changed this particle emits electromagnetic
radiation. This physical principle is valid for acceleration, deceleration and also for any change of
direction of the movement of the particle.
The blue color of the sky, as well as the range of mobile phones or the energy limitations of circular
particle colliders are all connected by this fundamental principle. Also the generation of X-rays in
every X-ray tube can be derived.
In an X-ray tube electrons are accelerated by a high voltage of several 10 kV, sometimes more
than 100 kV, onto a massive heavy element target. There the electrons are subject to deceleration
in the strong electromagnetic field of the electron shells of the target material’s atoms. This
deceleration can be abrupt or gradually. The kinetic energy of the electrons has to be conserved
and is emitted in form of electromagnetic radiation, hence photons. The electromagnetic radiation
emitted in this process is called bremsstrahlung.
The energy of the emitted photons is not as defined as for inner-atomic processes. It depends on
the strength of deceleration. The only fixed value is the maximum energy. It is defined by the
maximum kinetic energy which in turn is equivalent to the voltage which accelerated the electrons
in the first place.
For example, an electron accelerated by a voltage of 50 kV holds the kinetic energy of 50 keV and
if stopped abruptly will emit a single photon of the respective energy. If the electron is deflected or
decelerated gradually in several steps, multiple photons of lower energy will be emitted. The sum
energy of the photons emitted by one electron is still limited to 50 keV but the individual portions
are arbitrary. Therefore the bremsstrahlung radiation spectrum is continuous.

Functional Principles
20 User Manual
In the X-ray tube, where fast moving electrons are used to produce the continuous excitation
spectrum for the measurements, some electrons will by collision transfer energy to inner shell
electrons bound to the target material atoms and ionize the atom. Subsequently a relaxation
process will take place that leads to the emission of characteristic X-rays, as described above. An
X-ray tube spectrum is therefore always composed of the continuous bremsstrahlung spectrum and
of the target materials characteristic fluorescence lines. Within the sample in turn, where a
continuous excitation gives rise mainly to a characteristic line spectrum the photo-electrons
produced during the initial energy transfer are fast-moving and can, hence, produce
bremsstrahlung radiation in the sample.
The X-rays produced in the sample are emitted isotropically. Only a small fraction of them is
emitted in the direction of the detector and can be detected.
3.2 Detection of X-ray Quanta
There are several quite different concepts for detecting X-rays. They all are however driven by the
same basic necessity to transform photons into a signal which can be processed by electronics, i.e.
a voltage or current. Ideally not only the number but also the energy of the incident photon can be
derived from this electric signal.
In the M1 ORA/MISTRAL two different types of detectors are available:
Proportional counter detector (PCD),
Silicon drift detector (SDD).
The proportional counter detector is a cylindrical capacitor filled with gas, usually Argon, and with
an entrance window which is transparent for X-rays. The incident photon ionizes multiple Ar atoms
on its way through the detector. The produced electrons and ions are accelerated in the strong
electric field between the electrodes. Close to the anode, which is a thin wire in the center of the
detector, the field becomes very strong and the electrons gain enough energy to ionize secondary
Ar atoms whose electrons themselves can ionize further atoms. The resulting avalanche creates
enough free charges to form an easily detectable current. Since the number of initially ionized Ar
atoms is proportional to the energy of the detected photon the intensity of the current is
proportional to the incident photon energy. However, with the intermediate avalanche effect being a
highly statistical process the energy resolution of a proportional counter is limited.
Silicon drift detectors are solid state detectors; the incident photon is absorbed in a silicon crystal
and electron-hole-pairs are created. Again, the number of created charge carriers is proportional to
the incident photon energy. The electrons are collected in an electric field and guided to the anode
where they are detected as a current pulse. In contrast to the proportional counter the electrons
detected are all produced by the incident X-ray quant. There is no additional statistical process
involved. This yields a much better energy resolution than for the PC detectors but the current
created by X-rays with energies of ~ 10 keV is still only in the femtoampere regime and needs
higher effort for signal amplification and shaping.