Companies willing to provide a flash presentation may mark their interest when registering, providing a short description of the topic of their presentation. Presentations must focus on the technical challenges, avoiding standard commercial presentations of the companies. Depending on the available time and the number of companies interested, it might be necessary to make a selection.
Vacuum beampipes technologies
Technical challenges: the construction of a vacuum system of this size requires a significant effort to optimise the choice of materials, manufacturing processes and tube treatments to reduce costs, as it is estimated to account for 1/3 of the total cost of the ET (cost estimation in 2020). The final design must allow for a feasible, cost-effective manufacture by industry. In the workshop, we will address different topics such as welding techniques, dust contamination during welding, and detection of real and virtual leaks, among others. We will also address how to define realistic tolerances and fabrication methods, as well as IPR management. Logistical and organizational aspects dealing with manufacture and storage will be discussed as well.
Participating industries may take part in flash presentations in the following topics:
-
Fabrication approach of the vacuum tubes: flat sheets with longitudinal welds vs spiral forming and welding of the material.
-
Large scale production of the beampipes: logistics and operational challenges: in-situ vs ex-situ production, alignment of production with the pace of installation vs. increase of storage needs, etc.
-
Welding techniques: methods compatible with UHV (TIG, PAW, laser welding, etc.) trying to minimize the length of welded joints to be performed in the tunnel.
-
Corrugated pipe design vs smooth VIRGO-like pipe design.
-
Quality assurance: including control of raw materials (measurement of material composition, grain size, distribution of inclusions, surface state, mechanical properties and outgassing rates), leak detection (welding monitoring, manufacturing defects, vacuum leaks at joints, valves or seals), dust contamination, contamination control.
-
Vacuum chambers: industrial production capabilities, including surface finishing.
Vacuum Towers technologies:
Technical challenges: the exceptionally high production rate, with an average throughput of some towers per month. Specific methods will be required to ensure surface conditioning and cleaning at a very high grade, starting from typical hot-rolled stainless steel quality and achieving inclusion-free, low-outgassing finishes.
Another key objective shall be to establish dedicated standards for UHV-grade constructions, possibly by adapting ISO approaches from fields where surface control is critical, such as life sciences, food processing, cleanroom technology, or semiconductor manufacturing. The adoption of standards will also facilitate the implementation of rigorous QA and QC processes and strengthen collaboration with industrial partners.
Further innovation is also expected for components and solutions already present in the market, here demanding for optimization to meet specific gravitational waves’ requirements and to mitigate otherwise prohibitive costs: UHV gate valves up to 1 m aperture, safety-qualified viewports, and 1 m size metal seals with a 50-year lifetime.
Participating industries may take part in flash presentations in the following topics:
- Industrial capability for high fabrication rate of large vacuum chambers.
- High-grade surface finishing, cleaning and conditioning process (cleaning, baking, firing).
- Contamination control: dust particulate.
- Contamination control: low-volatile residuals.
- Standards and certification from other industrial processes, e.g. life science, pharmaceutical, food processing, semi-conductor.
- Low-outgassing electro-mechanical components.
- Viewport for long-term GW use.
- Affordable large metal seals.
- Large UHV gate valves
Cryogenics:
Technical challenges:
- Thermal noise: The sensitivity of the gravitational wave detectors is limited by the thermal noise of the suspended mirrors, which depends on the dissipation coefficients of the system (for which the choice of the material is critical) and its temperature. The design of the last stage of the mirror suspension is also critical, with crystalline silicon with high mechanical Q at low temperature for components like triangular blade springs and suspension fibers to be used.
- Heat Extraction: The heat generated by the powerful laser light absorbed by the mirrors must be efficiently extracted through ultra-low stiffness thermal links with high conductivity to maintain the cryogenic temperature without introducing mechanical noise.
- Vibration isolation: mechanical vibrations from the cryoplant must be reduced and the residual effects meticulously isolated. Superattenuator stacks will be used to dump vibration at low temperature.
- Ice Formation: Residual gas molecules in the ultra-high vacuum chamber, especially water, can freeze onto the cold mirror surfaces, forming a layer of "frost" that degrades the mirrors' optical and thermal properties. The progressive increase of the monolayers on the mirror surface determines a change in the mirror absorbance and, as consequence, of its temperature, making it almost impossible to operate the interferometer in a stationary noise condition. New methods are being developed to prevent and control the frost.
- Multilayer insulation at zero pollution: new UHV-compatible solutions based on contamination-free materials as alternatives to traditional multi-layer insulation.
Participating industries may take part in flash presentations in the following topics:
-
Cryogenic payloads for the ET-LF suspensions.
-
Cryopumps for the ET-LF. Frost reduction.
-
Materials: crystals under stress at low temperature.
-
Vibration isolation and dump of residual vibrations across transfer lines ofcryo-liquids.
-
Soft thermal links designed to cool cryogenic components like mirrorsand suspensions without transmitting vibrations.
-
Contamination-free superinsulation materials.