This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Objectives X29 has been developed to provide high speed synchrotron access for macromolecular crystallography for both dedicated Protein-Structure Initiative applications, such as its PRT partner, NYSGXRC, and also for the broader General User crystallography community. Results The 'High Speed' aspect of beam line X29 has permeated our operations and development program in 2005. We have systematically improved and optimized instrumentation, software, and the general environment for user operations in our quest for high productivity from our investments at X29. The X29 operations team has worked in conjunction with specialists within the PXRR, the NSLS, the user community and operators of other beam lines around the world to steer this refinement. We have joined the NSLS in addressing improved user access with improvements to the NSLS s Proposal, Allocation, Safety, and Scheduling system. An important advance has been implementation of the 'Macromolecular Envelope Safety Approval.' However, our own 'Rapid Access' system continues to provide the proposal and scheduling venue for most user access to PXRR beam lines until PASS is working properly. Our program continues to drive the unification of beam time-access portals within the NSLS. The PXRR is now providing a streamlined request avenue for users of the NSLS bend magnet beam lines to bring their demanding crystals to the PXRR insertion device beam lines (X29 and later X25) for two-to-four-hour beam-time slots. In particular, there is now an ID quick project request within our data-base-grounded rapid-access procedure that can provide response within minutes. The similarity of approach within the software for operations of the four PXRR bend magnet beam lines allows the users to be able to make productive use of these short slots at X29. Automatic systems within X29 manage the beam line x-ray optics and undulator such that the user is not burdened beyond the selection of wavelength. The mini-Kappa design, combined with the precision air bearing omega spindle, provides both simplified operation (both for loading crystals from liquid nitrogen and also for adjustment of crystal axis orientation) and the precise motions needed for the short exposures commonly employed at X29 (about one second exposure with one degree oscillation). The small scale construction of these parts has allowed for full motion of these mechanisms so the user needs not be concerned about equipment bumping. The large size, readout speed, reliability, and signal-to-noise of the ADSC Q315 detector plays a significant role in providing the user with a fast and high quality data collection environment at X29. Although we have focused the operation of X29 on fast acquisition of standard crystallography experiments, we have found that users with more demanding projects are pleased too. For instance, X29 users with large unit cell crystals are enthusiastic about their ability simply to adjust the horizontal focus of the beam, and to re-position crystal axes with the mini-kappa. Users with very small crystals enjoy the simple adjustment of the aperture. And of course, the high flux benefits all of the users in that it greatly speeds their work. Finally, we have found that the users have responded to the expanding of scheduling models for X29, in that they can more easily fulfill their experimental needs with responsive and fluidized scheduling modes combined with simplified operations for this high flux beam line. We have steadily increased the user support we provide for beam line X29 as the throughput of experimenters at the beam line has increased over the past year. The PXRR currently provides four PX-operators, two on day shifts and two on evening. These PX-operators are the first contact person for users with questions and problems. The PXOps can resolve most problems immediately, while others may require that the PX-operator seek help from our broader support environment. The point generally is to increase the effectiveness of the user's beam time by seamlessly attaching the experience and expertise of the PX-operators. Plans We know that there are improvements that can be made in the functioning of the monochromator. In particular, we know that if we make precise manual adjustments we can gain twice the intensity. However we don t know how to do this automatically. We will study the problem and find a solution. Secondly, we know that we can improve the signal-to-background situation, especially for long-wavelength data, and will study this. An obvious solution will be to introduce a He-filled chamber surrounding the tip of the collimator and the beam stop. Finally, we expect gradually to increase the staffing to lubricate further the interaction among all of our beam lines, producing a sea of photons in which the experimenters can swim.
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