Welcome to the Outgassing Database for Ultra-High Vacuum (UHV) Experiments
This database, initially developed to support the Einstein Telescope (ET) project in gravitational wave detection, is now accessible to all vacuum experts worldwide. It aims to be a comprehensive repository of
outgassing data from literature and vacuum laboratories across the globe. These data are crucial for ensuring the integrity and performance of sensitive optical equipment
in large-scale research instruments like in ET project.
About the Database : The European Gravitational Observatory (EGO), home to the Virgo interferometer in Europe, hosts this database. Together with LIGO in the USA, we represent the largest UHV experiments in the world.
Purpose : Our goal is to provide a centralized source of vacuum outgassing for materials, assemblies, and components used in UHV chambers. Additionally, we want to include any relevant surface quality measurement data to indicate the best materials fabrication and treatment processes. By contributing to and using this database, you help advance our collective understanding and capability in maintaining high-performance vacuum systems for cutting-edge research.
Data Submission Policy :
Policy to add data :
- Registration : Write an email to vacuum@ego-gw.it to register. You will be given credentials to modify the Outgassing Database.
- Literature-Referenced Data : Submissions should reference established literature.
- Lab Measurements Data : Data from both ET collaboration and external laboratories are welcome, provided they come with a comprehensive explanatory report.
- Report Template: A template for outgassing and surface quality test reports is available.
Database Guidelines :
- Component Creation/Selection :
- Choose Component from the list or create a new one by selecting '+'. Remember to save by clicking the save icon.
- 'Item' column : indicates briefly the component origin with a few keywords
- 'Manufacturer' column : indicates the component producer origin
- 'Main material' column : indicates the main material composition under study
- Vacuum Measurements :
- 'Test procedure' column : indicate the test method used (Throughput method etc..)
- Outgassing rates are generally expressed as N2 equivalents
- Low Volatile Compound 'Hydrocarbon' (HC) detection includes all fragments > 44m/z.
- Background values are subtracted, and level > 44m/z compounds are flagged as potential contaminants for optical surfaces at room temperature.
- 'Q_HC (level>44)' column : indicates the sum of outgassing rates for level > 44.
- 'Peaks N>44' column : List the most relevant peaks > 44 m/z.
- 'OTHERS' columns refers to gases that do not fit the HC definition, such as CO, CO2, CH4, O2, etc..
- 'Comments' columns refers to cleaning procedure used including pre-baking
- 'Units' column: indicates the measurement units used (Torr-L/(cm2-s) or mbar-L/(cm2-s) or Pa-m3/(m2-s) if mono-material or mbar-L/s if multi-material component)
- Surface Quality Measurements :
- Include a document link containing surface quality measurements (roughness, porosity, surface contamination), using any optical techniques like SEM, XPS, Raman, XRR etc..
- Data Updates :
- Data can be updated anytime
- An 'History' icon in the Entry column allows to trace changes.
References: [1] Vacuum Procedures to Measure and Report Outgassing Rates, [2] Outgassing and Optical Contamination Template Report
| Component |
Vacuum measurements |
Surface Quality measurements |
|
Item |
Main material |
Manufacturer |
Test procedure |
Q_H2O @24h |
Q_H20 @100H |
Q_H20 @1000H |
Q_H2 |
Q_N2+OTHERS @24h |
Q_N2+OTHERS @100h |
Q_HC (level>44) |
Q_HC (peaks N>44) (m/z) |
Units |
Comments |
Experiment |
Reference document |
Test procedure |
Reference document |
|
|
Titanium (ASTM Grade 2) |
Ti (ASTM Gr. 2) |
N.A. |
throughtput method |
1.50e-10 |
3.61e-11 |
3.61e-12 |
2.50e-14 |
|
|
|
|
mbar-L/(cm2-s) |
Q_H2O : Q=Qo*t^-alpha, with Qo=1.3e-3(Pa L s-1 cm-2) and alpha=1 |
|
NIST: DOI: 10.1116/6.0000657 |
|
|
| Date |
Done by |
Modification |
| 31-03-2025 |
sentenac |
- Comment changed from: Qo=1.3e-3(Pa L s-1 cm-2) and alpha=1
|
| 31-03-2025 |
sentenac |
|
| 25-03-2025 |
gargiulo |
- Sample preparation highlights changed from:
|
| 25-03-2025 |
gargiulo |
|
| 18-10-2024 |
gargiulo |
- Notes changed from: Q_H2O : Q=Qo*t^-alpha, with Qo=1.3e-3(Pa L s-1 cm-2) and alpha=1
|
| 25-11-2022 |
gargiulo |
- Notes changed from: xxx
- Reference text changed from: xxx
|
|
|
|
Baffle PCB#10-21 |
Pyralux AP |
IFAE |
throughtput method |
1.03e-8 |
5.43e-9 |
1.94e-9 |
|
|
3.31e-11 |
5.00e-13 |
|
mbar-L/s |
|
Virgo |
IMC Instrumented Baffle, Ref. IFAE-PCB#10-21 |
|
|
| Date |
Done by |
Modification |
| 25-03-2025 |
gargiulo |
- Experiment changed from:
- Units changed from:
|
| 25-11-2022 |
gargiulo |
- Optical losses (ppm) changed from: 0.5
|
|
|
|
Al EN AW-6061 |
Al EN AW-6061 |
N.A. |
throughtput method |
4.86e-10 |
1.17e-10 |
1.17e-11 |
5.50e-14 |
|
|
|
|
mbar-L/(cm2-s) |
Q_H2O : Q=Qo*t^-alpha, with Qo=4.2e-3(Pa L s-1 cm-2) and alpha=1 |
|
NIST: DOI: 10.1116/6.0000657 |
|
|
| Date |
Done by |
Modification |
| 01-04-2025 |
gargiulo |
|
| 31-03-2025 |
sentenac |
|
| 18-10-2024 |
gargiulo |
- Notes changed from: Q_H2O : Q=Qo*t^-alpha, with Qo=4.2e-3(Pa L s-1 cm-2) and alpha=1
|
|
|
|
AISI 316L Vacuum Fired |
AISI 316L |
N.A. |
throughtput method |
8.64e-11 |
2.43e-11 |
3.21e-12 |
5.10e-14 |
|
|
|
|
mbar-L/(cm2-s) |
Vacuum fire process: 950°C for 24h Q_H2O : Q=Qo*t^-alpha, with Qo=3.30e-4(Pa L s-1 cm-2) and alpha=0.91 |
|
NIST: DOI: 10.1116/6.0000657 |
|
|
| Date |
Done by |
Modification |
| 01-04-2025 |
gargiulo |
|
| 31-03-2025 |
sentenac |
|
| 18-10-2024 |
gargiulo |
- Notes changed from: Vacuum fire process: 950°C for 24h
Q_H2O : Q=Qo*t^-alpha, with Qo=3.30e-4(Pa L s-1 cm-2) and alpha=0.91
|
| 28-09-2022 |
gargiulo |
- Main material changed from: AISI 316L Vacuum Fired
|
|
|
|
AISI 316L |
AISI 316L |
N.A. |
throughtput method |
1.20e-10 |
3.09e-11 |
3.48e-12 |
1.00e-12 |
|
|
|
|
mbar-L/(cm2-s) |
Q_H2 : conventional outgassing rate Q_H2O : Q=Qo*t^-alpha, with Qo=7.25e-4(Pa L s-1 cm-2) and alpha=0.95 |
|
NIST: DOI: 10.1116/6.0000657 |
|
|
| Date |
Done by |
Modification |
| 01-04-2025 |
gargiulo |
|
| 31-03-2025 |
sentenac |
|
| 18-10-2024 |
gargiulo |
- Notes changed from: Q_H2 : conventional outgassing rate
Q_H2O : Q=Qo*t^-alpha, with Qo=7.25e-4(Pa L s-1 cm-2) and alpha=0.95
|
|
|
|
AISI 304L |
AISI 304L |
N.A. |
throughtput method |
2.68e-10 |
4.19e-11 |
2.10e-12 |
1.00e-12 |
|
|
|
|
mbar-L/(cm2-s) |
Q_H2 : conventional outgassing rate Q_H2O : Q=Qo*t^-alpha, with Qo=7.00e-2(Pa L s-1 cm-2) and alpha=1.3 |
|
NIST: DOI: 10.1116/6.0000657 |
|
|
| Date |
Done by |
Modification |
| 01-04-2025 |
gargiulo |
|
| 31-03-2025 |
sentenac |
|
| 18-10-2024 |
gargiulo |
- Notes changed from: Q_H2 : conventional outgassing rate
Q_H2O : Q=Qo*t^-alpha, with Qo=7.00e-2(Pa L s-1 cm-2) and alpha=1.3
|
| 28-09-2022 |
gargiulo |
- Vacuum measurement: Q_H2O @100h changed from: 0.000000000419
- Notes changed from: ---
|
|
|
|
RMC_coil_001 |
Kapton / PEEK |
EGO |
Rate of Rise |
|
6.20e-8 |
|
2.80e-8 |
|
9.30e-9 |
8.00e-10 |
69 |
mbar-L/s |
Pre-baking hours: 147 |
|
ISB-VC-0039 |
|
|
| Date |
Done by |
Modification |
| 01-04-2025 |
gargiulo |
|
| 31-03-2025 |
sentenac |
- Test procedure changed from: throughtput method
|
| 31-03-2025 |
sentenac |
|
| 01-02-2022 |
gargiulo |
- Pre-baking hours changed from: 147
|
| 20-10-2021 |
gargiulo |
- Test procedure changed from: Rate of Rise
|
|