OLAV-VI: 6th Workshop on the Operation of Large Vacuum Systems

15 Apr 2024, 00:00 → 19 Apr 2024, 23:59 America/Chicago

One West (Fermi National Accelerator Laboratory)

Alex Chen (Fermilab)

Welcome to the 6th Workshop on the Operation of Large Vacuum Systems (OLAV). OLAV workshops are tailored for professionals engaged in the design and operation of expansive vacuum systems, with a particular focus on their application in particle accelerators and facilities of Gravitational Wave Observations. However, we extend a warm invitation to experts from various fields to join us, as we believe that the challenges posed by large-scale systems, encompassing numerous components and vast volumes, transcend disciplinary boundaries.

The spectrum of vacuum systems under discussion spans from high vacuum to extreme high vacuum (XHV) and low particulate vacuum for SRF. For instance, we explore topics such as the vacuum isolation systems employed in large cryogenic setups and the particle beam transport conduits integral to particle accelerators.

Our workshop is designed to foster the exchange of practical insights pertaining to the design, installation, and operation of vacuum systems. The primary format comprises oral presentations enriched by in-depth discussions. In previous iterations, we have found the combination of presentations on best practices alongside discussions of specific failure cases to be exceptionally enlightening.

Furthermore, we've included topical discussions on material properties and the unique challenges posed by specific vacuum components, and quality control. A noteworthy addition to this year's workshop is the exploration of vacuum systems characterized by minimal particulate contamination. An increasing number of projects now demand such contamination-free systems. This requirement arises, for instance, in cases where superconducting surfaces must endure exceedingly high radiofrequency fields or in the use of high-quality mirrors for the transportation of high-intensity photon beams.

The workshop agenda will encompass a broad array of topics, ranging from updates on major international facilities and institutes to the valuable lessons derived from past operational experiences.

Join us at the 6th Workshop on the Operation of Large Vacuum Systems (OLAV) as we embark on a journey to explore and learn together.

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Event Survey

OLAV as rare as Solar Eclipse.pptx

Monday, 15 April

Session 7

Convener: Hannah Fee (Accelerator Division)

Tuesday, 16 April

Welcome: Check In

OLAV Presentation.pptx

zwaska_olav.pptx

Welcome: Introduction to Fermilab and the Fermilab Accelerator Complex

Convener: Robert Zwaska (Fermilab)

OLAV Presentation.pptx

zwaska_olav.pptx

Welcome: House Rules

Convener: Lucy Nobrega (Fermilab)

OLAV Presentation.pptx

zwaska_olav.pptx

Session 1: Latest Developments at Institutes

Conveners: Jason Carter (Argonne National Laboratory), Kevin Duel

1 Status of the Development of Vacuum Systems for the PIP-II Particle Accelerator

The vacuum systems for Fermilab's PIP-II particle accelerator have undergone Final Design Reviews. These systems include low-particulate Ultra High Vacuum for the superconducting section of PIP-II, as well as and cryomodule insulating vacuum and vacuum systems for the Warm Front End and Beam Transfer Line. A description of the systems' design and the integration with other particle accelerator systems will be presented.

Speaker: Raul Campos (Fermilab)

PIP-II Vacuum Systems.pptx

2 HL-LHC Vacuum upgrade

The luminosity upgrade program (HL-LHC) requires modifications of the present LHC’s vacuum system, in particular the inner triplets, new crab cavities, matching section and experimental areas. Such modifications must follow strict guidelines: increased stored current implies a higher thermal power in the beam screen from the image current moving along with the stored particles and stronger synchrotron radiation (SR) and electron cloud (EC) effects, which in turn translate into higher degassing rates. An overview of the vacuum layout modification and upgrade will be presented and discussed.

Speaker: Mr Josef Sestak

OLAV_Bregliozzi_HL-LHC.pptx

10:30 Group Photo - Atrium

10:45 Coffee Break

3 LHC Experimental beam vacuum during long shutdowns: Upgrades and new challenges

Experimental beam vacuum systems located within experimental caverns of ALICE, CMS and LHCb experiments successfully passed major upgrades during the Long Shutdown 2. The layout of the machine at ALICE cavern was upgraded based on physics performance requirements. A new central beryllium chamber compatible with new Inner Tracking System was installed and commissioned during the pandemic year 2020. Experimental vacuum system of the CMS detector underwent the most extensive change since its installation in 2008. The new layout, including central beryllium chamber compatible with Phase 2 tracker as well as 30 meters of custom-built aluminium vacuum chambers supported by optimized structural supporting system was installed commissioned during spring 2021. Experimental vacuum system of the LHCb detector remained the same as during the LHC Run 2, however the most sensitive part of the entire system, the Vertex Locator (VELO) passed an upgrade containing also both beam and detector vacuum systems. Foreseen layout changes during the Long Shutdown 3 involving experimental beam vacuum systems will be also discussed as well as production challenges for both aluminium and beryllium vacuum chambers.

Speaker: Josef Sestak (CERN)

OLAV_Sestak_v1_3.pptx

4 Status of the LHC injectors, experimental areas and LHC insulation vacuum

The injector chain of the Large Hadron Collider (LHC) underwent significant upgrades during the Long Shutdown 2, spanning from 2019 to 2021, aimed at achieving the beam quality necessary for the High-Luminosity LHC. This contribution serves as a continuation of the report presented in the preceding OLAV workshop [1]. It describes the upgrades and modifications implemented, alongside the encountered challenges during installation and commissioning. Additionally, it provides an overview of the operational experience gained thus far. This review extends beyond the LHC accelerator chain to incorporate various experimental areas such as HiRadMat, ISOLDE, nTOF, AWAKE, and more. Notably, ELENA has achieved full operational status following the installation of the new electron cooler and transfer lines, with the inaugural delivery of antiproton beams in 2018. Looking forward, this contribution also addresses the principal future challenges including the upcoming Long Shutdown 3 (spanning from 2026 to 2029) and beyond.
[1] J.A. Ferreira, Status of LHC injectors and experimental areas, 5th Workshop on the operation of large vacuum system OLAV, 2017, DESY Hamburg, Germany. https://indico.desy.de/event/16256/

Speaker: Jose Antonio Ferreira Somoza (CERN)

Status of the LHC injectors, experimental areas and LHC insulation vacuum.pptx

5 Latest Development at CLASSE

After a very successful CHESS-U upgrade in 2019, two new special new X-ray beamlines are currently under development at CLASSE. One of them is the High Magnetic Field (HMF) beamline, which allows users to study material properties under up to 20-Tesla field. The other is the XLEAP (X-ray for Life, Environment, Agriculture and Plant Sciences) beamline. The CHESS-U vacuum system performance and the status of these new beamlines will be presented.

Speaker: Yulin Li (Cornell University)

Latest Development at CLASSE.pptx

6 Overview and Status of ALS-U Project Vacuum Systems

The Advanced Light Source upgrade (ALS-U) project has entered it's execution phase. Majority of the vacuum system design is complete and aspects of the system are in the procurement, assembly and installation phases. The new vacuum system spans the new accumulator ring, replacement storage ring and three new transfer lines

Speaker: Sol Omolayo (Lawrence Berkeley National Lab)

ALS-U_Upgrade_Vacuum_OLAV-VI.pdf

ALS-U_Upgrade_Vacuum_OLAV-VI.pptx

12:40 Lunch (on your own)

Session 1

Conveners: Jason Carter (Argonne National Laboratory), Kevin Duel

7 ESS VACUUM SYSTEM UPDATES

The European Spallation Source (ESS) is a multi-disciplinary research infrastructure neutron source facility based on a 2GeV-5MW proton linear accelerator (LINAC). The goal of ESS is to be the brightest neutron facility and to enable novel science in many fields such as biology research, environmental technologies and fundamental physics. The facility includes Super-conductive Radio-frequency cavities (SRF) to accelerator a proton beam to produce neutron by spallation process on a helium-cooled tungsten wheel, possibility to host 42 neutron instruments. The ESS Vacuum Group has the overall responsibility for all technical vacuum systems used on the Accelerator, Target and Neutron Scattering Instruments (NSS).

It will be given an overview of the ESS Vacuum System updates, on the Accelerator, Target and NSS, as of Q1-2024 for the vacuum hardware and some details about the Vacuum Control system. The vacuum system includes the Proton Accelerator (NCL, SCL and A2T areas), the Target monolith with the proton beam window and the Neutron Instruments from the bunker area until the Sample chambers and in vacuum detectors. A short introduction about ESS Vacuum Laboratory and activities correlated will be given.

Speaker: Marcelo Juni Ferreira (European Spallation Source ERIC)

OLAVVI MJFa.pptx

14:05 Session Discussion

Session 2: Low Particulate Vacuum System Design and Best Practices

Conveners: Bob Donahue (FNAL - AD/MSD), Yulin Li (Cornell University)

8 Status of the Vacuum Systems of the FAIR Accelerator Complex -

The FAIR (Facility for Antiproton and Ion Research) accelerator complex is under
construction at the GSI campus in Darmstadt in Germany. In the current realisation phase it consists of about 2km of beam vacuum system, where the vacuum requirements are different for almost all machines. While in the fast ramped SIS100 one has to deal with cryogenic and bakeable at room temperature operated sections with static vacuum pressure in the lower $10^{-12}$ mbar regime, the high energy beam transfer system has moderate vacuum requirements of $10^{-8}$ mbar. In the Super-FRS one has beside the moderate vacuum of $10^{-6}$ mbar to $10^{-8}$ mbar to cope with a high radiation area close to the target.
With beginning of this year the projects entered a new phase as the first components are installed in the accelerator tunnel, while the civil construction and procurement of components is still ongoing.
An update on the status of the vacuum system will be presented.

Speaker: Andreas Kraemer (GSI Helmholtzzentrum für Schwerionenforschung GmbH)

OLAV_VI-AKraemer_20240416_final.pptx

9 LCLS-II-HE cryomodule production at Fermilab

The Linac Coherent Light Source (LCLS) is an X-ray science facility at SLAC National Accelerator Laboratory. The LCLS-II project (an upgrade to LCLS) is in the commissioning phase; the LCLS-II-HE (High Energy) project is another upgrade to the facility, enabling higher energy operation. An electron beam is accelerated using superconducting radio frequency (SRF) cavities built into cryomodules. It is planned to build 24 1.3 GHz standard cryomodule for the LCLS-II-HE project. Fourteen of these standard cryomodules are planned to be assembled and tested at Fermilab. This paper presents the status of the production.

Speaker: Tug Arkan (Fermilab)

Arkan-OLAV.pptx

10 LCLS-II Particle Free Vacuum System: assembly and commissioning

The LCLS-II (Linac Coherent Light Source II), a revolutionary new X-ray laser, is currently operating at SLAC National Accelerator Laboratory. In the past years SLAC has operated and tested the capability of this new machine. This presentation gives a comprehensive overview of the accelerator vacuum systems state, performance, challenges, and potential relation with vacuum system and RF cavity performance. The presentation encompasses the preparation, testing, particle-free cleaning, assembly, and installation of ultra-high vacuum (UHV) components for the LCLS-II beamline, aimed at meeting the stringent requirements of LCLS-II.

Speakers: Giulia Lanza (SLAC National Accelerator Laboratory), Robert Coy (SLAC National Lab)

OLAV 2024 - GL RC.pptx

15:40 Coffee Break

11 Operational Experience of a Cryomodule Test Stand for LCLS-II Cryomodules

CMTS1 (cryomodule test stand 1) at Fermilab was built to test cryomodules built for the LCLS-II beamline at SLAC and is currently testing cryomodules for LCLS-II-HE, the high energy upgrade to LCLS-II. The first cryomodule test was in 2016 and to date over 30 cryomodules have been tested here. This talk will highlight operational experience of the vacuum systems including insulating, coupler, and a low particulate beamline vacuum system. It will focus on the problems that have come up over the years, their solutions, and mitigations put in place to prevent further issues.

Speaker: Brian Hartsell (Fermilab)

20240414 Hartsell OLAV CMTS Operation.pdf

20240414 Hartsell OLAV CMTS Operation.pptx

12 Low Particulates Vacuum Operation in SRF Cavity and String Assembly

Foreign particles may unexpectedly enter SRF cavities and cause cavity performance degradation. Stringent protocols related to the vacuum operations of an SRF cavity system are paramount for high-quality assembly. This presentation will describe those protocols, the lessons learned, and the current and future studies to improve the SRF vacuum system further.

Speaker: Genfa Wu (FNAL/TD)

Low Particulates Vacuum Operation in SRF Cavity and String Assembly.pptx

13 the Protection of low particulate vacuum for SRF from catastrophe failure of neighboring UHV

In accelerators based on SRF technology, low particulate vacuum is required. it is critical for SRF operation to minimize the immigration of particulates in vacuum system into the SRF region, in case of catastrophe vacuum failure in neighboring area. Fast action valves( close within 10ms) are equipped and tests were done PIP2IT. test results and analysis will be presented.

Speaker: Alex Zuxing Chen (Fermilab)

ProtectionVacuumOLAV2.pdf

14 Field installation of cryomodule vacuum systems at Fermilab

This talk will summarize experience with field installation of SRF cryomodules at Fermilab, including temporary cleanroom setup, low particulate vaucum practices,vacuum protection,and cryostat vacuum practices.

Speaker: Curtis Baffes (Fermilab)

Baffes - OLAV VI - Field Installation of Cryomodule Vacuum Systems at Fermilab.pptx

17:40 Session Discusion

Session 10: Reception

Convener: Hannah Fee (Accelerator Division)

Wednesday, 17 April

Session 3

Conveners: Brian Hartsell (Fermilab), Josef Sestak (CERN)

15 Overview of the Vacuum Pumping Systems for the SPARC Tokamak

Commonwealth Fusion Systems (CFS) is a spin-off of the Massachusetts Institute of Technology that aims to bring fusion energy to the grid. CFS is building SPARC—a compact, high-field, deuterium-tritium-fueled tokamak—in Devens, Massachusetts to demonstrate a fusion energy gain of Q>1. SPARC is a crucial step to develop the technologies and refine the physics necessary for ARC, a commercial fusion power plant capable of delivering net energy to the grid.

The vacuum pumping systems of SPARC include the cryostat pumping system, the leak detection system, and the torus pumping system. The cryostat pumping system is responsible for generating and maintaining the vacuum environment necessary for insulating the superconducting magnets. The leak detection system provides vacuum guarding of secondary vacuum interspaces throughout SPARC. The torus pumping system carries out four functions: containing tritium, achieving and sustaining the primary vacuum vessel base pressure, recovering inter-pulse vessel pressure, and providing particle control during plasma discharge via divertor pumping in conjunction with operation of a variable conductance valve.

Each subsystem is equipped with a pair of dry screw pumps for rough vacuum and fore line pumping, mag-lev turbomolecular pumps to achieve ultra-high vacuum, and residual gas analyzers for leak detection and analysis of plasma exhaust composition. Both the cryostat and torus pumping systems feature custom tritium-compatible, closed-loop, refrigerator-cooled cryogenic pumps to temporarily enhance pumping speeds. In addition, the cryostat and torus pumping systems feature piping up to DN540, which calls for the development of a custom CF-style knife-edge flange.

This talk will provide an overview the SPARC vacuum pumping systems and associated challenges.

Speaker: Oliver Mulvany (Commonwealth Fusion Systems)

OLAV VI CFS VACP Shared.pdf

16 The Vacuum Systems of LIGO - operations, challenges, further improvements. CE - the interferometer of the future

We are detecting gravitational waves at the Laser Interferometer Gravitational-Wave Observatory (LIGO). As gravitational waves cause periodic distortions in spacetime, to detect them, LIGO needs to be able to measure the slightest change in length. To achieve this, LIGO's arms were built to be 4X4 km long, their diameter is ~1.2 m, so the relative measurement precision is "only" 1/10,000 of the diameter of a proton. The resultant facilities are the 2nd and 3rd largest vacuum systems in the world, one in WA - Hanford Site, and the other in LA - Livingston Site. To operate such vacuum systems in a very low noise level, only noiseless, or very silent pumping technologies can be used, to maintain the UHV pressure. The biggest challenge is to get to that pressure as soon as possible, and in parallel with this, to get rid of the residual water, hydrogen, and hydrocarbons: to achieve this, some projects and vacuum R&D activities have been proposed. This presentation aims to describe these research activities, describe the longer-term projects, and give a taste of the everyday vacuum tasks.
In the future, to cover the whole observable universe, a 10 times bigger, a 40X40 km observatory is being planned: Cosmic Explorer. The physics behind CE is self-explanatory - 10 times longer arms, 10 times higher sensitivity. However, the additional challenges are vast on the technological side, especially in vacuum engineering.

Speakers: Janos Csizmazia, Adam Branch

LIGO_general_Turbo Brain.pptx

17 Designing the MAGIS-100 Vertical Beamline Vacuum System

The Matter-wave Atomic Gradiometer Interferometric Sensor, also known as MAGIS-100, is a quantum sensor being designed for installation at Fermilab and aims to explore dark matter and test quantum mechanics with a 100-meter-long atom interferometer. The main components of this sensor are three atom sources, an interferometry laser system, and an ultra-high vacuum (UHV) system. Design of this 100-meter UHV system in a vertical orientation, minimizing dust for the optical components, and protecting the system from stray magnetic fields present additional challenges. Beam tube coatings may also be required to prevent scattering of lasers used in the system. This presentation will focus on the requirements, design, and installation challenges of this vacuum system.

Speakers: Linda Valerio (Fermilab), Lucy Nobrega (Fermilab)

OLAV MAGIS 100 Vacuum Design April 17 2024 final.pdf

18 Impact of the 2024 Noto Peninsula Earthquake on the Vacuum Equipment of KAGRA, the Large Cryogenic Gravitational Wave Telescope

At 16:10 (Japan Standard Time) on January 1, 2024, a subduction earthquake occurred 16 km beneath the Noto Peninsula in Ishikawa Prefecture, Japan, and shaking of intensity 3 or lower was observed in an underground tunnel in Kamioka-cho, Hida City, Gifu Prefecture, where KAGRA is installed.
In this presentation, we report on the effects of the 2024 Noto Peninsula earthquake on the KAGRA vacuum system. The report will include the status of the vacuum pumps that were stopped by the earthquake motion and the forces applied to the two 0.8 m diameter, 3 km long vacuum ducts that consist of KAGRA.
In addition, the status of the vacuum pumps evacuating KAGRA's vacuum ducts in the high humidity environment of the underground tunnel will be presented.

Speaker: Dr Yasunori TANIMOTO (KEK)

OLAV-VI_KAGRA_Kimura.pptx

10:10 Session Discusion

10:30 Coffee Break

Session 4

Conveners: Linda Valerio (Fermilab), Marcelo Juni Ferreira (European Spallation Source ERIC)

19 Vacuum system of RAON

The vacuum requirements of the RAON heavy ion accelerator were determined from the beam optics calculations. The vacuum system was designed to meet vacuum requirements using 3D Molflow+ code with realistic outgassing values of the vacuum chambers, cavities and beam pipes. This paper presents the specification and configuration of the vacuum system including pumps, gate valves, and vacuum gauges of the Super Conducting LINAC 3 (SCL3) and Beam transfer line to low energy experimental facility. In addition, we will discuss the results of 3D Molflow+ calculations in these sections and the achieved vacuum levels after the installation of the vacuum system

Speaker: HYUNGJOO SON (Institute for Basic Science (IBS))

Vacuum System of RAON(OLAV VI)_Hyungjoo Son-3.pptx

20 Fabrication of vacuum components for the APS-Upgrade Storage Ring Vacuum System

The APS-Upgrade’s (APS-U) new storage ring vacuum system is an assembly of over 2400 custom vacuum chambers and photon absorbers. A number of vacuum component vendors were contracted to fabricate the majority of these components including NEG-coated vacuum chambers, photon absorbers, beam position monitor vacuum chambers. In addition, APS-U leveraged in-house aluminum welding expertise to fabricate over 160 2-meter length ‘L-bend type’ aluminum vacuum chambers. This presentation will discuss the fabrication timeline and results for all of the various chambers as well as challenges and solutions found along the way and how the high-quality production of vacuum components helped lead to a successful vacuum system installation.

Speaker: Jason Carter (Argonne National Laboratory)

OLAV-IV Fabrication of Vacuum Components for the APS-U.pptx

21 Status of the installation and commissioning of the APS-Upgrade Storage Ring Vacuum System

The APS-Upgrade (APS-U) project’s new storage ring vacuum system has been assembled and installed between 2022 and early 2024. Much of the vacuum system was pre-assembled during a ‘magnet & vacuum module assembly phase between 2022 and mid-2023 where 200 magnet modules (5 modules per each of 40 sectors) were assembled comprising about 90% of the storage ring vacuum system components. The magnet modules were brought into tunnel starting in the summer of 2023. Remaining vacuum interconnections were made between the fall of 2023 and early 2024 including beam position monitors (BPMs) connecting modules to each other and to straight section vacuum chambers, photon extraction lines connecting the storage ring to front ends, and Zone F straight section component installation. This presentation will share the status of the work performed, the challenges and solutions found along the way, and the status of beam commissioning as of April 2024.

Speaker: Tim Clute (Argonne National Laboratory)

OLAV-IV Installation of Vacuum Components for the APS-U.pptx

22 Magnet-Vacuum Module Assembly of the APS-Upgrade Storage Ring Vacuum System

The APS-Upgrade (APS-U) project’s new storage ring vacuum system has been assembled and installed between 2022 and early 2024. Much of the vacuum system was pre-assembled during a magnet & vacuum module assembly phase between 2022 and mid-2023 where 200 magnet modules (5 modules per each of 40 sectors) were assembled comprising about 90% of the storage ring vacuum system components. This assembly phase was performed at an offsite warehouse which was specially outfitted with storage and assembly spaces appropriate for UHV vacuum work. A team of technicians was trained to perform the work required to assemble and certify all magnet vacuum modules. This talk will discuss the work that helped make this magnet-vacuum module assembly phase a success including the scope of work, the facilities for assembly and inventory storage, inventory management, work planning and control, and the timeline of work performed.

Speaker: Nicholas Bechtold (Argonne National Laboratory)

Magnet-Vacuum Module Assembly of the APS-Upgrade Storage Ring Vacuum System.pptx

12:30 Lunch (on your own)

Session 4

Conveners: Genfa Wu (FNAL/TD), Junichiro Kamiya (Japan Atomic Energy Agency / J-PARC center)

23 Complex Bend Vacuum Chamber for NSLSII-U

While the NSLSII synchrotron is a third-generation light source providing outstanding brightness and flux, there is a robust R&D program in place to upgrade to a fourth generation, or beyond, facility. Inherent in the so-called complex-bend magnet and lattice designs are significant limitations on the beam and exit slot apertures of the vacuum chamber. These restrictions and the need for the vacuum chamber to be mechanically aligned and decoupled from the magnets impose unique challenges. As part of the design process, a thorough survey of existing fourth generation machines was completed to look at existing design solutions for accommodating beam and for providing adequate conductance and pumping. For our chamber, the selected solution is not novel and utilizes an aluminum split clamshell design that has been done in many machines past and present. The adaptation of this design along with improved machining and welding should provide the most cost-effective solution. The geometrical and impedance solutions and structural and thermal modeling will be shown along with dynamic pressure simulations generated by Synrad and Molflow modeling code. With continuing changes in lattice and magnet parameters, a systematic, iterative approach to vacuum design has been implemented and will be presented.

Speaker: Michael seegitz (Brookhaven National Laboratory)

OLAV Vacuum Chamber Design.pptx

24 Photon Stimulated Desorption Beamline at NSLSII

Understanding the expected gas desorption of an accelerator is critical in the proper design of accelerator vacuum systems and can have a major impact on the machine design and cost. From some of the earliest work on the subject for the Cambridge Electron Accelerator up through and including LHC, desorption measurements have played an important role in predicting vacuum behavior of large accelerators susceptible to synchrotron radiation. Much of this early work served well the machines they applied to and other machines with similar parameters and material choices. But as machines continue to be developed with higher energy and beam current, other novel materials are investigated to improve vacuum, while at the same time reducing Secondary Electron Yield to suppress e-cloud. Part of these investigations require careful study of their desorption yields. This would benefit future upgrades to the existing NSLS-II facility as well as other synchrotrons facilities. Additionally, such a beamline could have a major impact on the selection and validation of proposed materials and components for EIC, including possible coatings for the electron storage ring, IRs (Interaction Regions) and the beam screen of the Hadron/Ion ring. Desorption rates of these newly proposed materials would be used as inputs to advanced modeling tools such as Molflow and SynRad for accurate predictions of vacuum behavior. A beamline at NSLS-II, dedicated to the PSD/ESD study of novel and proposed vacuum materials has been constructed and commissioned to advance further research into desorption behavior. The PSD of stainless steel and OFHC copper to be used for the Rapid Cycling Synchrotron of EIC have been measured and compared to prior work to baseline the system, with plans to evaluate the NEG coated chambers for the EIC electron storage ring. The layout of the experimental line and the commissioning measurements will be presented.

Speaker: Robert Todd

14BM PSD beamline OLAV VI 2024.pptx

25 Dynamic vacuum simulation using isotherms

Over recent years, a variety of isotherm models have been employed at CERN to simulate a broad spectrum of scenarios. These models, originally developed from zero dimensional models prepared by Redhead [1] and Kanazawa [2] have evolved into more sophisticated 1D and 3D simulations. They have been used for diverse applications, ranging from optimizing bakeout for gravitational wave detectors to modelling XHV evolution in cryogenic traps, pumpdown dynamics, and water propagation in accelerators, among others. In this contribution, we provide a comprehensive overview of the various models employed and the wide diversity of problems they have been successfully addressed.

References:
[1] P.A. Redhead, Modeling the pump-down of a reversibly adsorbed phase. I. Monolayer and submonolayer initial coverage, J. Vac. Sci. Technol. Vac. Surf. Films 13 (1995) 467. https://doi.org/10.1116/1.579381.
[2] K. Kanazawa, Analysis of pumping down process, J. Vac. Sci. Technol. A 7 (1989) 3361–3370. https://doi.org/10.1116/1.576151.

Speaker: Dr Jose Antonio Ferreira Somoza (CERN)

Dynamic vacuum simulation using isotherms.pptx

26 Operational Experiences of NEG Dominated Pumping System at CHESS-U

Successful operations of the Cornell High Energy Synchrotron Source Upgrade (CHESS-U) have proven the in-service reliability of the compact non-evaporable getter (NEG) pumps in a new experimental vacuum system predominantly pumped with distributed NEG-strips and modular high-capacity NEG pumps. The 80-meter section improvement in the Cornell Electron Storage Ring (CESR) is composed of 6 double-bend achromats operating with a single positron beam up to 200 mA. After a successful commissioning period, a vacuum level of 10-9 Torr was achieved with minimal maintenance and NEG re-activations.
The CHESS-U vacuum system experienced a catastrophic failure when a beam steering error created a pinhole leak in an undulator vacuum chamber (0.6-mm wall). The installed NEG-dominated pumping system had demonstrated an adequate pumping performance, which allowed a quick recovery and reconditioning of the affected 20+ meter vacuum section. With the hard work of the technical staff, X-ray user operations were able to resume after 10 days of recovery efforts (chamber fabrication and replacement, vacuum conditioning). The accidental air-exposure to the NexTorr pumps (combination of ion pump and NEGs) resulted in minor Argon instability issues that required mitigation. Corrective actions were developed in areas such as thermal monitoring, chamber construction, and beam steering while also granting the opportunity to test the pumping integrity of the effected NEG pumps after the exposure.
The 3-year operational experiences of the NEG pumping system will be presented.

Speaker: Leila Aboharb (Cornell University)

Aboharb_OLAV2024.pptx

15:10 Coffee Break

Session 4

Conveners: Genfa Wu (FNAL/TD), Junichiro Kamiya (Japan Atomic Energy Agency / J-PARC center)

27 Design Status of Vacuum System for the Korea-4GSR

The 4th generation storage ring project in Korea (Korea-4GSR) has begun in 2021 and is scheduled to be completed in 2017. The 800-meter long storage ring is designed to store 62-pm rad emittance electron beam with numbers of strong magnets, resulting in spatial restriction for the vacuum system. To overcome the low gas conductance of the vacuum chamber, the main idea we have employed is to use aluminum extruded chambers having slots for the 'pill-type' getters as a distributed pumping system. This concept has been used in the PLS-II storage ring without any operational problems during the last 10 years. Φ10 mm ST2002 getters from SAES company is being tested for this purpose. The pumping speed of the getters has been measured before and after being inserted into the slots of the chamber. Two cartridge heaters will be installed in the grooves on both sides of the aluminum chambers to make possible in-situ activation of the getters in the tunnel at 180℃ for 24 h. Besides the aluminum extruded chambers, several types of chambers constructing a supper-period such as beamline branch chambers, fast corrector chambers, BPMs, RF-shielded bellows, pumping tees and photon mask chambers, have been also designed. It will be presented the overall design status of the vacuum system for the Korea-4GSR and the measurement results of vacuum performance of some prototype chambers.

Speaker: Taekyun Ha (Pohang Accelerator Laboratory)

OLAV-VI_Ha_20240417.pptx

28 Vacuum Performance of the Prototype Chamber for the Korea-4GSR

The performance of the main vacuum chamber of the Korea 4th generation storage ring (Korea-4GSR) was evaluated. The hydrogen outgassing rate of the aluminum extrusion chamber was measured using the gas accumulation method. After heat treatment for 150°C-48 hours, the outgassing rate is approximately 1E-13 mbar l/s cm². The pumping speed of the pill-type getters was measured under various activation conditions before inserting them into the chamber. The results were compared with the pumping speed of the getters which underwent ultrasonic cleaning using isopropyl alcohol for particle removal. The pumps were arranged using the distributed pumping scheme. Nine hundred pill-type getters were inserted into 3 slots of the 3 m-long chamber proto-type. The base pressure of this chamber after 180°C-24 hours getter activation is 5E-11 mbar. We also measured the pumping capacity of this chamber by injecting hydrogen gas until saturation of the getters. This result will be used to optimize the design of the vacuum system as well as to predict the reactivation timing of the getters during the commissioning stage.

Speaker: Ms Sehyun Kim (Pohang Accelerator Laboratory)

20240409_OLAV_4GSR_KSH_V6.pdf

29 Vacuum simulation of the Korea 4th Generation Storage Ring

The Korea Fourth-Generation Storage Ring (Korea-4GSR) has an ultra-low beam emittance of 62 pm·rad which demands spatially restricted vacuum system. The conventional vacuum system using lumped pumps is not suitable to guarantee the required vacuum level in this conductance limited system. To overcome the limited space for vacuum components, we employed a distributed pumping system with pill-type getters. The electron beam channel is octagon-shaped with an inner diameter of 24 mm (H) x 18 mm (V) and multiple slots for getters are located beside the beam channel. Getters are inserted into the slots along the beam direction, serving as primary pumps, while ion pumps are intermittently positioned for inert gas pumping. In the preliminary phases of commissioning, it is necessary to predict the performance degradation of the getters attributable to high dynamic pressure, enabling the proactive determination of reactivation timing. In the operational stages after beam cleaning, it is imperative to attain an average dynamic pressure of 10-9 mbar to ensure sufficient life time of the electron beam at 400 mA. We conducted a vacuum simulation using Synrad and Molflow+ to optimize the vacuum system.

Speaker: Hosun Choi (Pohang Accelerator Laboratory, POSTECH)

HosunChoi_Vacuum simulation of the korea 4GSR.pptx

Session 11: Two Brothers Roundhouse 205 N. Broadway Aurora, IL 60505

Convener: Hannah Fee (Accelerator Division)

Thursday, 18 April

Session 4

Conveners: Marcelo Juni Ferreira (European Spallation Source ERIC), Mayling Wong-Squires (Fermilab)

30 Vacuum firing effect on stainless steel & titanium

Vacuum firing, which is a heat treatment at high temperature in a high vacuum furnace, is known as the method for the outgassing reduction of the vacuum materials, such as stainless steel, titanium, etc. The outgassing rate of the vacuum-fired stainless steel is known to be low after ordinal baking at 150-200℃. In this research, the effect of the vacuum firing (850℃ for 10 h) on the stainless steel and titanium is investigated from the vacuum and surface point of view. The build-up test of the vacuum chambers clearly showed the outgassing suppression by the vacuum firing. Especially, the hydrogen outgassing, which was the main component after baking, was much reduced. Thermal desorption spectroscopy showed that the vacuum firing reduced the desorption of H2, H2O, CO, and CO2 with high desorption energy even after air exposure. Especially the effect on the H2 was very large. X-ray photoelectron spectroscopy (XPS) showed the increase of ferric oxide and the decrease of chrome oxide on the near surface of the vacuum-fired stainless steel. On the other hand, the XPS also showed that the chrome oxide was systematically increased by heating from 200℃ to 400℃. These results support the outgassing reduction mechanism by the vacuum firing that the hydrogen is reduced from the bulk due to the diffusion to the vacuum phase during the vacuum firing and the surface metal oxides are reformed as a diffusion barrier from the gas phase to the bulk. For the titanium, the surface titanium oxide film was once removed by the vacuum firing and the reformed oxide film is thinner. Thus the it is possible that the vacuum fired titanium chamber easily have the getter funcution by the baking.

Speaker: Junichiro Kamiya (Japan Atomic Energy Agency / J-PARC center)

Kamiya_OLAV VI VacuumFiring_r01.pptx

31 Ceramic Beam Tube Coating Investigation for LBNF Kickers

The addition of the Long Baseline Neutrino Facility (LBNF) to Fermilab requires the installation of six extraction kickers into the current Main Injector beamline. These kickers will have beam tubes made of high purity alumina ceramic due to their necessary very low magnetic properties. This benefit is offset by undesirable electrical and secondary electron yield (SEY) properties. Ceramic beam tube coatings were investigated to improve electrical properties and reduce SEY while maintaining a low outgassing rate compatible with ultra-high vacuum systems.

Speaker: Jason Morin

Morin OLAV LBNF Ceramic Tube Coating.pptx

09:20 Session Discussion

09:50 Coffee Break

session 5: Session 5

Conveners: Curtis Baffes (Fermilab), Hsiao-Chaun Hseuh

32 Beam-induced heating of the LHC warm bellows

Vacuum modules are an essential component of the room temperature sectors of the LHC. They enable to cope with misalignment and thermal expansion/contraction of equipment while keeping the connection vacuum-tight and ensuring good electrical contact between the beam components. The currently installed modules in the LHC machine are composed of a vacuum body and a RF insert. The RF insert guarantees the electrical contact and carry the image current generated by the circulating particles with the use of a series of thin beryllium copper RF fingers kept in place on a copper transition tube using a stainless-steel spring. This strategy ensures electrical continuity between adjacent vacuum chambers, effectively reducing the beam impedance through electromagnetic shielding of the outer bellows. In 2023, during beam intensity increase up to 1.6∙1011 protons per bunch up to ≈2500 bunches, some failures of the RF inserts happen limiting the bunch intensity in the LHC machine. An overview of the design and understanding of these failures will be presented and future upgrades discussed.

Speaker: Mr Eric Page (CERN)

OLAV-VI_CERN_PAGE_VM.pptx

33 Operation of the European XFEL vacuum system

The European XFEL (EuXFEL) is a 3.4 km long free electron laser that started commissioning in 2016. The machine can be divided into the superconducting LINAC with a length of 1.7 km and the following SASE sections. The latter sections use the accelerated electron beam with energies up to 17.5 GeV to generate 27,000 ultra-short flashes per second with a wavelength of 0.05 nm to 4.7 nm. These properties - unique to any free electron laser worldwide - allow researchers to explore ultra-fast processes on a femtosecond scale.

This presentation will provide an overview of the operation of the EuXFEL vacuum system since 2016. It shall focus on the performance of the vacuum systems in the cold and warm sections of the electron beam lines. The concepts achieved during the design phase will be explained and resulting effects for daily operation and shutdown tasks highlighted. It will deal with unexpected challenges during commissioning, with the control of the system itself as well as permanent ongoing modifications. Finally, the increasing amount of particulate free sections and their influence on the procedures concerning the main vacuum system will be pointed out.

Speakers: Katharina von Chamier (DESY), Lukas Müller (DESY)

Operation of the European XFEL vacuum system LM KVC 20240418.pptx

34 The Photon Beamline Vacuum System of the European XFEL. First years of operation (2017-2023): An overview.

The European XFEL is a hard X-ray free-electron laser (FEL) with MHz repetition rate, based on a high-electron-energy superconducting linear accelerator. Located in Schenefeld, near Hamburg, Germany, the facility started operation in April 2017 and now provides extremely intense X-ray beam pulses to seven scientific instruments, up to three of them simultaneously by means of a multiplexed delivery configuration. Both the transport beamlines and the instruments are located underground in a fan-like photon beamline configuration that comprises a length of more than 3 km.

The photon beamline vacuum system is essential to retaining the beam properties and reliable operation of the many optical and diagnostics components distributed along the different beamlines. It also provides non-conventional functionality that enables the modulation of the photon flux delivered to the softer X-ray regime beamline experimental end-stations.

The present contribution offers an illustrative overview of this young facility, describing some of the key experiences accumulated from the early days of operation until the present and describing how these experiences are helping us to shape, optimize, and consolidate methods, protocols, and operational plans in order to sustain the current performance with minimum downtime.

Speaker: Raúl Villanueva Guerrero (European X-Ray Free Electron Laser Facility)

2024.04.18 - VILLANUEVA - OLAV VI - FP.pdf

35 MAX IV 3 GeV NEG coated storage ring status

The vacuum system of the 3 GeV storage ring at MAX IV laboratory is based on a fully NEG (Non-evaporable Getter) coated, extruded copper pipe (22 mm inside diameter) that also serves as a distributed absorber intercepting synchrotron light. The ring has been in operation since the end of 2015 and performs very well. This presentation is summarizing the design and performance of the 3 GeV storage ring.

Speaker: Mr Marek Grabski (MAX IV Laboratory)

Grabski OLAV VI MAX IV 3 GeV vacuum system.pdf

36 Vacuum-related Operational Experience from PETRA III

PETRA III is a third generation synchrotron light source situated at DESY in Hamburg, Germany. Since its commissioning in 2009 and extension in 2015, the 2.3 km long storage ring has been the basis of one of the world’s brightest light sources of its kind, and it is continuing to do so with respect to its future upgrade to PETRA IV. Throughout the years in operation, a lot of experience was gained. We will address the operational experience acquired between 2014 and 2024, with a focus on availability, examples of vacuum-related failures and modifications of the vacuum system. Moreover, a summary of NEG-related tests in the framework of PETRA IV will be presented. These comprise the evaluation of 12 partially NEG-coated dipole chambers that were installed at PETRA III in 2019 without in-situ activation.

Speaker: Nils Plambeck (DESY Hamburg)

OLAV_VI_session_5_PETRA_III_Plambeck.pdf

OLAV_VI_session_5_PETRA_III_Plambeck.pptx

12:15 Lunch (on your own)

session 5

Conveners: Kevin Duel, Lutz Lilje

37 FRIB Fragment Separator Vacuum Operational Experience

FRIB approaches 2 years of successful operation of its Advanced Rare Isotope Separator (ARIS). This presentation reports on the experience gained by the FRIB Vacuum Operation Group in commissioning, operation, maintenance, troubleshooting, and repair of the vacuum systems of ARIS.

Speaker: Brandon Ewert

OLAV VI FS Vacuum Presentation(1).pptx

38 Vacuum system with turbomolecular pumps for high-power proton beam operation of the rapid cycling synchrotron

This presentation reports the improved vacuum system for the high-power beam operation in the rapid cycling synchrotron (RCS) from two perspectives: (1) Improved turbo molecular pump (TMP) system to prevent the failure caused by the high-intensity beam loss and (2) establishment of the pressure runaway suppression method through an understanding of the dynamic pressure mechanism. We describe the failure event of the TMP caused by the high-intensity beam loss. The countermeasure against such TMP failure is explained. We also describe the pressure runaway during the highpower beam operation. Then,the dynamic pressure mechanism is verified by comparing the measurement with the analytic calculation. The critical parameters for the pressure runaway are also elucidated by the calculation. Finally, we describe the effect of the additional NEG pumps to suppress the pressure runaway.

Speaker: Junichiro Kamiya (Japan Atomic Energy Agency / J-PARC center)

Kamiya_VacuumSystemTMP_OLAVVI_r01.pptx

39 Recent Improvements and Developments of Vacuum System of J-PARC 3 GeV Rapid Cycling Synchrotron

The 3 GeV rapid cycling synchrotron (RCS) of J-PARC delivers a 1 MW proton beam. The RCS vacuum system has two main characteristics: turbomolecular pumps as the main evacuation and 200-400 mm large aperture, 1-3 m long alumina pipes. To realize the high intensity beam operation, the RCS beam and the beam pipes are thick for reducing space-charge force, and the extraction kicker magnets having large surfaces are installed inside the vacuum to prevent discharge due to high voltage application. Turbomolecular pumps are suitable to evacuate the high volume vacuum chamber including high outgassing rate components. The electromagnets are excited at 25 Hz (up to MHz order for injection shift bump magnets), and alumina beam pipes are utilized inside the all electromagnets to prevent eddy currents. To stabilize and maintain the vacuum system, we are improving the fore-line pumps from dry scroll pumps requiring unexpected maintenances up to three times in a year to Roots pumps, and we are re-developing the alumina beam pipes to manufacture small-quantity spares because fifteen years have past from manufacturing the pipes in mass production during construction. Roots pumps have not been require unexpected maintenances over 5 years operation. In addition, we are upgrading the vacuum level with installing non-evaporable getter pumps to realize future heavy ion acceleration and/or more than 1.5 MW operation in J-PARC. The vacuum pressure successfully decreased with NEG pumps installed at low outgassing sections from around 1e-6 Pa to less than around 1e-7 Pa due to evacuation of hydrogen as expected.

Speaker: Ippei YAMADA (J-PARC/JAEA)

ippei_yamada.pptx

14:30 Session Discussion

15:00 Coffee Break

Session 6

Conveners: Lucy Nobrega (Fermilab), Yasunori TANIMOTO (KEK)

40 Fermilab Drift Tube LINAC Tank 5 Water-to-Vacuum Leak Repair

In late 2022 tank 5 of Fermilab’s Drift Tube LINAC (DTL) started experiencing a gradual degradation in vacuum level due to a water-to-vacuum leak on a cooling line that ran internal to the vacuum chamber. The leak was in a difficult to access location and pinpointing and repairing the leak would have resulted in significant operational downtime. A unique method for sealing the leak internally to the cooling tube was learned from colleagues at another national lab and used successfully to repair the tank 5 leak.

Speakers: Kathrine Laureto, Kevin Duel

Duel_LINAC Tank 5_OLAV VI.pptx

41 The photon beamline vacuum control system at European XFEL

The European XFEL is a free electron laser (FEL) facility located in northern Germany. It is a non-profit company, that was built in collaboration with 12 countries and started operation in 2017.
The 3,4 km long underground facility starts at DESY (Deutsches Elektronen Synchrotron) in Hamburg and provides up to 27.000 ultrashort X-ray pulses per second to the experimental hall in Schenefeld in the state of Schleswig-Holstein, where the pulses are distributed to three beamlines.

To ensure the stable FEL beam transportation to the experiments it is essential to have a reliable control system. This presentation provides an overview focusing on the photon beamline vacuum control system developed at European XFEL that includes PLC based vacuum interlocks and pressure monitoring to protect the vacuum system from uncontrolled pressure increases in the case of vacuum leaks and around gas injection sections. It also provides the long term logging of pressure data and the in-house developed SCADA system Karabo. Furthermore, this talk gives an overlook about the PLC-controlled mobile pumping stations, which are used after maintenance work to evacuate vacuum sections and provide a multiplicity of options for recommissioning.

Speaker: Mrs Janni Eidam (European X-Ray Free Electron Laser Facility)

Photon beamline control system.pptx

42 Remote RGA operation via ultra-long (100 meters) extender cables

Residual gas analyzers (RGA) are regarded as essential gas-composition monitoring instrumentation for both high and ultra-high vacuum processes. High Energy Physics vacuum installations often place RGA sensors within ionizing radiation environments, which can degrade semiconductor and other components of their control/analysis modules. Radiation sensitive electronics components can be protected from such harsh radiation exposure, positioning the electronics control unit (ECU) at a remote location - away from the quadrupole mass filter (QMF) subsystem - and through an extender cable connection between both modules. Extender cables include mixed connection paths for conveying (1) mass spectrometry signals (mass setting and ion currents), (2) control signals (electrode biases), (3) power lines (filament current supply) and (4) high-amplitude radiofrequency signals for mass selection (coaxial transmission line.) Critical to the operation is the delivery of precisely controlled dual-phase RF supply signals to the QMF assembly, as required to achieve repeatable mass spectra. The RF supply signal amplitude is of the order of hundreds of volts peak-to-peak (Vpk) and its frequency is typically a few MHz. With modern vacuum installation projects demanding cable lengths exceeding 50 meters, our engineering team recently developed a patented methodology for (1) conveying a time-varying voltage signal from ECU to QMF including (2) monitoring and adaptively controlling the amplitude of the time-varying voltage signal at the QMF. A physical length of the transmission line configured to correspond to an electrical length substantially equal to a positive integer multiple of one-half wavelength of the time-varying voltage signal allows the transmission line to operate resonantly and adaptively control the amplitude of the time-varying voltage signal from the ECU for cable lengths exceeding 100 meters. Ultra-long extender cables, specifically designed to match customer specified lengths, are presently a reality and the preferred solution for the operation of RGA under hard radiation environments.

Speaker: Gerardo Brucker (MKS Instruments, Inc.)

OLAV VI_50_100m Cable_v1.pptx

16:35 Session Discuss

Session 9: Next OLAV

Next OLAV

Convener: Lucy Nobrega (Fermilab)

43 KEK proposal for OLAV-VII

Speaker: Yasunori TANIMOTO (KEK)

OLAV VII Proposal Japan.pptx

44 PAL proposal for OLAV-VII

Speaker: Taekyun Ha (Pohang Accelerator Laboratory)

OLAV-VII proposal_PAL.pdf

Friday, 19 April

Session 8

In preparation for your upcoming visit to Argonne National we will need you to complete the registration below as soon as possible. This will need to be submitted and your registration will need to be fully approved in order to gain site access to Argonne.

Please complete the visitor registration at https://apps.anl.gov/registration/visitors. Please usejade.thomas@anl.gov as the Sponsor/Host E-mail. Note, for education background, you must include the university, type of degree and date of degree.Please be sure to upload a copy of your passport and CV/ Resume as well as any relevant immigration documents (Example: ESTA/ WVB/ VISA) when filing in the visitor registration as this is also need for submission.

In addition to the visitor registration form each person will need to complete Contractor Safety Orientation. This training is valid for one year so if you have done it in the past, it still may need renewing. Please follow the instructions on this page: Contractor Safety Orientation Remote Training Instructions | Advanced Photon Source (anl.gov)

Convener: Jason Carter (Argonne National Laboratory)