This article explains the changes, lays out dates and timelines, and other helpful information for users currently doing research at CHESS and those eager to do so in the future.
CHESS-U is happening!
Before getting into details, everyone needs to know that the CHESS-U project to upgrade the storage ring and rebuild the X-ray experimental floor is on track to be a great success! Wilson laboratory is filling up with new equipment, hutches, accelerator magnet girders, undulators, monochromators, and power supplies. Our biggest challenge right now is that we’re completely out of space to store, stage, and commission the new equipment.
CHESS shutdown period – alternative beamlines
AT 7:00 AM on June 4, 2018, the current operating period will conclude and the CHESS-U installation will begin. A1, A2, B1, C, and D lines, CHESS ops, the RF power supplies adjacent to A2, and the sextant of CESR running through Wilson lab will be completely removed and replaced with the new accelerator and x-ray beamlines. CESR commissioning is scheduled to begin in November, 2018. The first x-ray time for users will be on the current F and G stations sometime in early 2019. New beamlines will be commissioned at a rate of roughly one or two per month in 2019. Information about new beamlines is discussed below.
Current CHESS users are, of course, concerned about where they can do their research during the down period. In the table to the right, the CHESS beamline scientists have identified experimental stations and techniques at other light sources with similar capabilities to the current CHESS.
What’s going away
During the CHESS-U installation, none of the CHESS experimental hutches will have x-ray beams. After the installation, CHESS will be in a completely new configuration. Users need to consider where they will do their research. Many current capabilities are being enhanced, others are going away.
One of the goals of the CHESS-U project is to upgrade the accelerator to run only a single particle beam. In the future CHESS will operate with CESR
running only clockwise (the current positron direction) particles. This is the direction currently utilized by the CHESS East and G-line stations.
Existing stations A1, A2, B1, C1 and D1 will be decommissioned and removed. In order to maximize the space available for large x-ray hutches, the radiofrequency power supplies next to A2 that power CESR, the door from A1 to the CESR tunnel, and the power supplies behind that door in the CESR tunnel will all be relocated. The figure below shows the new x-ray experimental floor plan, including space that was reclaimed last summer by removing the CLEO particle physics detector.
Not shown in the figure is the G-line area, where the G1, G2 and G3 experimental stations will remain. You’ll note from the figure that the labeling of experimental stations is also changing. Station labels now begin with the sector number (specifying straight section in CESR), followed by a letter identifying the insertion device that produces the x-ray beam. For example, sector 2 has two undulators, labeled ID2A and ID2B. The hutches share those names.
The new x-ray beamlines are being outfitted with new monochromators and focusing optics. Each of the new experimental stations is being optimized for a specific research application.
What’s coming in shiny and new
In addition to the physical changes, CHESS is going through a major transition in its funding model and organizational structure.
Beginning April 1st 2019, NSF will no longer be the steward of CHESS. Cornell University has created a new funding model for CHESS in which multiple partners will steward facilities at CHESS. CHESS will operate and manage x-ray beamlines for the partners. CHESS is seeking partner support for all ten beamlines.
Going forward, Cornell is proposing to operate a sub-facility called CHEXS (Center for High-Energy X-ray Science) at CHESS for the NSF. CHEXS will be the NSF’s national user facility at CHESS.
Early in 2018 Cornell submitted a proposal to NSF to operate the “Center for High-Energy X-ray Sciences” at CHESS, or CHEXS@CHESS. The proposed facility consists of six beamlines which will form the National User Facility. Our goal is to preserve the “CHESS culture” and to operate with very similar proposal submission, review, safety and beamtime allocation policies and mechanisms. The CHEXS proposal is under active review and a final determination of the funding level and number of beamlines will be forthcoming from the NSF in late 2018.
The scientific themes of the proposed CHEXS facility came out of the science workshops held in 2016 (which were developed in detail in “New Science Made Possible by CHESS-U), reviewed by NSF and CHESS advisory committees, and in additional workshops. The 6 beamlines which have been proposed to NSF are:
Forming and Shaping Technology (FAST): this beamline will support sub-millisecond time-resolved studies of manufacturing processes such as laser welding and rapid quenching. The rich datasets obtained will rigorously benchmark transformational new models enabled by advanced computational tools.
High-Pressure Biology (HP-Bio): with sophisticated new sample cells the “HP-Bio” beamline will enable precise high-pressure structural studies of protein molecules and complexes to help determine the” rules of life” at the molecular level, a regime not currently accessible to biologists.
CHEXS Bio-Microprobe (CBM): the CBM beamline will, through 2- and 3-dimensional x-ray fluorescence imaging, discover the mechanisms by which plants absorb, control, and exploit metal ions to perform critical life-functions, from the sub-cellular regime to the whole-organism scale. A new partnership with the Cornell School of Integrative Plant Science (SIPS) will provide CHEXS users access to greenhouses and plant growth chambers, creating a unique facility.
Q-Mapping for Quantum Materials (QM2): this beamline will provide high-throughput characterization of quantum materials in reciprocal space (also known as “Q-space”) to uncover intertwined quantum correlations of spins, charges, and orbitals, from high to low temperatures and spanning entire phase diagrams.
Photon-in, Photon-out X-ray Spectroscopy (PIPOXS): this beamline will enable spectroscopic studies of valence electronic states in functional materials using hard x-rays, allowing access to opaque materials or sample environments. In situ and operando studies of man-made catalysts and enzymes will be the initial focus with additional applications to fuel-cells, batteries, and electronic excitations in quantum materials.
In Situ Materials Processing (IMP): this beamline will enable in situ, operando, real-time studies of processing of soft materials (conjugated molecules and polymers, nanoparticles, block co-polymers).
MacCHESS will be submitting a proposal in early October to support its programs. MacCHESS hopes to support (serial)macromolecular crystallography (MX) and biological small angle x-ray scattering (BioSAXS). The NIH will make a decision on that proposal sometime in the spring of 2019.
CHESS is seeking additional partners to support the four additional beamlines. At present, eight other potential partnerships are at various stages of negotiations, and as plans become firm they will be announced.
Some present CHESS capabilities, including HP Diamond Anvil Cell (DAC) studies and thin-film deposition (G3), are not currently being actively explored by potential partners. Without partner support, CHESS cannot continue to support these capabilities.
Future call for proposals
Given the dramatic changes on the CHESS experimental floor, all existing proposals for scientific work at the facility will “expire” on June 4th 2018. New proposals will be solicited in the fall of 2018 for beamtime in 2019. The CHESS User Office will work with users to make the transition as smooth as possible. We are hoping that current users will be able to update existing proposals (if appropriate) for research at future beamlines.
CHESS understands that while these changes create opportunity for many users, they also create uncertainty and, in some cases, disruption or even hardship for other users. We are doing our best to ensure that the quality of the user experience is as good or better as you’ve come to expect from CHESS.