Announcement Archives

6/17/99 ~ 06/11/99 ~ 11/11/98 ~ 10/29/98 ~ 10/20/98 ~ (8/20/98) ~ 8/12/98 ~ 8/4/98 ~ 7/27/98 ~ 7/20/98 ~ 6/18/98 ~ 6/11/98 ~ 6/2/98 ~ 5/21/98 ~ 5/20/98 ~ 5/11/98 ~ 4/30/98 ~ 4/22/98 ~ 4/16/98 ~ 4/7/98 ~ 3/31/98 ~ 3/24/98 ~ 3/16/98 ~ 2/27/98 ~ Intro from new director ~ Farewell ~ Proposal Deadlines (1/16/98)

• The 5ID mirrors have been installed and are now under computer control. Staff encountered some problems with noise pickup in the control system, but these have now been sorted out. Since DND beamline for this exercise is now over for this run, further characterization will continue in 1999-4. However, the mirrors are available to be used for experiments for the rest of this run after coordination with DND Staff. In addition, Staff's studies have shown that the mirror vessels need to be shifted by about 1 cm in order to increase the angular range of the system. Currently, the maximum angle is approximately 5 to 6 mrad. The mirrors have three stripes (Pt, Glass, and Rh) which can be moved into the beam. Staff has not tried to focus the beam with the mirror yet. This requires setting several motor parameters while looking at the beam to insure that the mirrors are not over bent.

• DND Staff is also reinstalling the sagittal crystal bender in 5BM for further tests. The white beam Be window has been installed in 5BMD on a translation mechanism that will allow the window to be moved vertically to accommodate the focussed BM beam as well as white beam. The mechanism does not have the range to fully intercept the beam. A new bellows is due to be delivered today that will extend the range.

• The computer for the SAXS/WAXS system was damaged during shipment from DND to the CCD vendor (Photometrics). DND has repaired the system and is resending it to the vendor. The delivery target for the SAXS/WAXS system is the middle to end of August.

• DND has issued an order to MAR USA for a service contract on the CCD detector system until May 30, 2000.

• APS has changed the operating mode for this run and probably future runs in order to work up to top up mode. Currently, the ring is running a fill pattern that has reduced current lifetime. To compensate, the ring is refilling twice a day with the front end shutter open. This should reduce some of the thermal transients due to temperature fluctuations on our optics.

• The 5ID front end shutter (i.e. the shutter that provides delivers radiation from the APS to the 5ID optics) is having intermittent failures due to a faulty pneumatic cylinder. APS can not repair the cylinder until the shutdown. Fortunately, the APS floor coordinators can reset the error and the experiments can continue. So, if the shutter fails while you are here, notify the floor coordinator.

• DND-Staff has made significant progress on the bending magnet beamline.

• Shielded transport was installed between the 5BMB and the 5BMC enclosures along with pass through shielding through 5BMC to carry the beam into 5BMD. This effectively split the bending magnet fan into two separate beams. 5BMC, 5BMD and the shielded transport passed white beam shielding verification and DND was authorized to begin operations in 5BMC and 5BMD.

• One side of the bending magnet fan feeds station 5BMC and the other side feeds 5BMD. 5BMB is currently not being used for experiments and is waiting for the development of a third optics path. Operations were moved from 5BMB into 5BMD in January 1999. A simple crystal cage was installed in the 5BMC monochromator so that preliminary experiments could be performed in 5BMC. Space constraints in 5BMC limit the kinds of experiments that can be performed in that enclosure.

• DND has taken delivery of two Ge(220) crystals to be used as analyzer crystals for high resolution powder diffraction. DND has also purchased a commercial fortran compiler for Linux that supports VAX/VMS FORTRAN extensions. This should allow existing computer codes for powder diffraction analysis to be more easily ported to the DND beamlines.

• During installation of the 5ID mirrors, DND staff discovered a serious flaw in the mounting design for the mirrors. The flaw caused the mirrors to chip at the mount points. After consulting with Larry Rock Design, the mirror mounts were redesigned and remanufactured. The 5ID mirrors have been installed in the 5ID beamline and DND staff is currently performing tests on the mirrors with the 5ID beam.

• In January 1999, DND installed a sagittal focussing monochromator in the 5BM beamline. While DND staff was able to achieve a focus with the beam, testing time ran out and DND removed the bender so that operations could continue. DND staff will reinstall the bender again during the current run to continue testing and characterization of the beam .

• DND staff has found a buyer for the RAXIS IV system from MSC. The system was sold to New Century Pharmaceuticals Inc. The detector has already been shipped to New Century and they are currently installing it in their facility.

• DND staff now has a Collaborator Liability Agreement that all non DND member collaborators will be required to sign prior to working with DND members on the beamline.

• The SAXS/WAXS detection system from Photometrics is currently being constructed in Tucson. Delivery is anticpated sometime during the next run.

• DND has purchased a jig transit and an automatic level from Kara Co. to aid in aligning experimental equipment. Our goal is to perform as much setup as possible without using the x-ray beam since this will speed up setup and alignment.

• DND has installed a Bridgeport Milling Machine in the 432 LOM Machine shop. This gives staff the ability to make simple fixtures and pieces for beamline and experimental support.

• Dr. Steve Weigand has joined the DND staff as a post doc. Dr. Weigand come's from Prof. Wayne Anderson's group in the Northwestern Medical School. Dr. Weigand's will be working on coordinating the instrumentation efforts for the buildout of 5BMB.

• Beamtime requests for the first cycle in 1999 are due Nov 21.

• DND has hired Dr. Zdzislaw Wawrzak to lead our crystallography program at DND. Zdzislaw has experience in small molecule as well as protein crystallography and will take charge of the crystallography efforts at DND. He can be reached at 630-252-0223. John Quintana's phone has moved to 630-252-0221.

• Operations are continuing on 5BM and 5ID. During the machine studies on Tuesday, APS ran for several hours in a top up mode. During this mode, the APS injects a small amount of current into the ring in order to keep the intensity of the storage ring to within 0.1 mA out of about 95 mA. The injection pulse lasts about 30 ms and occured approximately every 70 seconds. During this time, DND monitored the effects of the 30 ms injection pulse on our 5BM EXAFS set up and the 5ID crystallography set up. No effect was noticed on the unfocussed bending magnet beam. Monitoring the intensity on 5ID did show the beam "cut out" during the 30 ms injection pulse. Zdzislaw is currently analyzing data frames collected from a lysozyme standard taken at different exposure times.

• The MAR-CCD developed a "sticky shutter" during the last user run. MAR USA has repaired the shutter. The malfunction resulted in occasional blank data frames in the data as well as occasional streaking in the data.

• The 5BM sagital crystal bender has arrived from Larry Rock Design. DND staff will begin fitting up the bender to the monochromator next week and designing and building the focussing crystal.

• Operations are continuing on 5BM. A minor problem developed in the 5ID monochromator yesterday while scanning the monochromator to low energies. A cable connection worked itself loose during operations and caused a short circuit on the second crystal adjustment coil as the monochromator angle increased. DND staff warmed up the monochromator to room temperature in order to open the monochromator tank. The tank was opened this morning and the short was easily found and repaired. DND staff are now in the process of resealing the monochromator chamber in preparation for pump down and recooling the crystal. DND does not anticipate that this will have an impact on user beamtime.

• Prior to the short circuit in the 5ID monochromator, DND staff evaluated the operating characteristics of DND's 20 cm long spectroscopy grade ionization chambers on the insertion device line. With the chambers filled with Helium, they were measured to be linear up to a current of 10 micro amps which corresponds to an incident flux of over 10**13 photons/second. Over the weekend, DND researchers began the first work using fast scanning EXAFS on the undulator. Since the APS is currently not setup to allow CAT's to change the speed of the undulator, these tests were performed by tapering the insertion device which broadened the energy spectrum from the undulator at the expense of peak intensity.

• The DND Management Board has implemented an abstract policy for all work performed at DND. After a user run is completed, investigators have six months to report results of the work to the DND Director in the form of an abstract that can be posted on the World Wide Web. Templates for the abstract are available on the DND web site. (Please see new instructions for downloading template page.) (If the user requests, DND staff will not publish the abstract on the WWW until the work has been submitted to/published in a peer reviewed journal). In the rare case where an abstract can not be provided, the investigator is still responsible for reporting to the DND Director as to the status/usability of the data as well as a date by which an abstract will be provided. Investigators who are delinquent in their reporting will be denied future beamtime access until reporting requirements are met. This policy was implemented for two reasons. First, the APS, DOE, and various funding agencies require periodic status reports of activities at the APS. Second, if a user is not obtaining usefull data, then the DND staff may needs to investigate if it is due to a malfunctioning of beamline systems. If you have any questions regarding this policy, please contact John Quintana at jpq@nwu.edu.

• DND has received four more SR570 Current Amplifiers for use with ionization chambers and photodiodes. DND has also received the vacuum flexible couplings for the transport to carry radiation from 5BMB to 5BMC/D. DND has received from the Argonne shop custom vacuum fittings to connect to the Xray Instrumentation Associates Filter/Shutter assemblies to standard KF50 vacuum fittings for easier integration into experimental setups.

• Beamtime requests for the first run in 1999 (1999-1) are due by 21 November 1998 (i.e just over a month).

• The 9th Annual APS User's Meeting was held at the APS from 13 October to 15 October 1998. All three DND member institutions were represented at the meeting. Scientific results from the DND beamlines were presented in the various talks and poster sessions at the meeting.

• In late September, John Quintana (DND) and J. David Londono (DuPont) traveled to the ESRF to observe experiments conducted by Keele University at the ID13 beamline. The primary purpose of this visit was to begin to explore techniques for microfocussing capabilities on the DND-CAT beamline.

• The DND-CAT Management Board held its annual meeting 15 October. The purpose of the meeting is to review any safety matters that need to be addressed as well as approve the budget and goals for the 1999 Fiscal Year.

• DND staff have ordered 6 additional spectroscopy grade ion chambers that have been used in 5BMB for EXAFS over the last two years. These chambers are manufactured by Larry Rock Automation Associates and procurement of parts has already begun. In addition, staff have ordered 8 additional SR 570 current amplifiers to be used with the ion chambers and photodiodes. DND has also ordered two of the Cyberstar Scintillation systems from Oxford Instruments. DND has taken delivery of a 90 degree eucentric goniometer head from Blake Industries.

• Mike Guise (DuPont) and DND staff have assembled a gas fill system for ionization chambers. This system uses refillable high pressure Hoke cylinders so that expensive gases (e.g. Krypton and Xenon) may be placed on the beamline. While the system has been equipped with a programmable logic controller so that automatic detector filling can be accomplished, the system will initially be used manually until a compatible pressure gauge has been procured.

• Installation of the white beam transport for 5BMC and 5BMD is continuing on the experimental hall floor. Tecknit Shielding has finished modifications on the wall penetrations so that beam may be carried through 5BMB to 5BMC and 5BMD. DND staff is currently rebuilding the Pb brick stack in the back of 5BMB so that operations can start on Thursday.

• Unistrut has been welded into the inside of the shielded transport to provide a mounting platform for beampipe components and extra Pb shielding to separate the two beampipes. DND has received the water cooled masks to be part of the internal collimators and is waiting on the delivery of Pb and other beampipe components. All long lead time items have been ordered for this project. Beam transport through 5BMC has been designed and is currently being manufactured in the Argonne machine shop.

• In order to use the ventilation system in 5BMC/D and 5IDB/C/D, the ventilation system running into the enclosures need to be shielded. DND has released a contract to Tecknit Shielding to manufacture and install the Pb lined covers for the ventilation system. Manufacture is currently underway. DND staff expects delivery of the covers sometime during the next experimental run. However, since the enclosures are in use, installation will be postponed until after the run is over.

• Early in September, a monochromator failure occurred in the mono providing beam to 5BMB. Due to a hardware failure, the crystal translation mechanism struck the second crystal of the monochromator into the first crystal mount. The second crystal was shattered. DND staff installed a new crystal and brought the beamline online after approximately 48 hours.

• Secretary of Energy Richardson visited the DND-CAT sector during his visit to the APS on 25 September. Michael Bedzyk discussed some of the unique aspects of the DND collaboration with the Secretary.

• The DND-CAT surface science chamber has left its temporary home in 5BMD and has been installed into 5IDC. Further work on this system will occur in 5IDC.

• The APS has switched the storage ring from positrons back to electrons for this run. The switch was performed in preparation for "top-off" mode. In this mode, the APS will reinject to maintain the current in the storage ring to a near constant state.

• The bending magnet line was brought back online for experiments. A few bugs were worked out with the QuickEXAFS setup so that it is now available for user's to test. Contact John Quintana at jpq@nwu.edu if you have interest in using this setup. The software is a bit "rough" at the moment, but Northwestern Researchers have so far collected data on over 140 samples during a 2 1/2 day run.

•  DND Staff has fitted a new gearbox on the phi drive of the six circle diffractometer. This was done to eliminate the servo hunting that user's experienced with the drive the last time it was used. Currently, adaptors are being made in the machine shop so that the analyzer circles can be used on the diffractometer.

• The APS has reported to DND that they have received approval to divert some of their funds to install a building wide liquid nitrogen system(LN2). The current proposal would provide a LN2 tap near the top of 5IDA. This would eliminate the need for moving Dewars to feed the LN2 pump that cools the first crystal of the 5ID monochromator. APS is currently asking the CAT's if we have any additional LN2 needs (e.g. feeding LN2 into the experimental enclosures for experiments). DND staff has ordered a third dewar to help minimize downtime from replacing the dewar in the front optical enclosure.

• Proposals for the next run (1998-5) are due August 22, 1998.

• Operations are continuing on 5ID and 5BM.

• DND staff completed installation of the new mirror tanks into both the 5ID and 5BM beamline. The reintegration of the vacuum systems was complete by Thursday (6 August) and 5ID was brought back online by Friday evening. Experiments started on 5ID with the first scheduled user on 11 August 1998 and operations are continuing. DND staff is now in the process of bringing up 5BM. Monochromatic beam was brought into the 5BMB enclosure on 11 August and staff is debugging a few problems introduced during the mirror installation.

• Currently, the mirror tanks do not contain the mirrors. These will be installed in a subsequent shut down period.

• Several additions have been made to the small angle scattering and EXAFS setups. Individual motions have been added to the front and rear sections of the small angle scattering beampipe. This makes it easier to align the beamstop at the end of the beampipe while minimizing motion of the front end. Staff installed a photodiode on the beamstop, however the vacuum bowing of the exit window caused the photodiode beamstop to break free of its mount. Staff will continue to sort out this problem. One of the small alignment lasers can now be used in this hutch to facilitate alignment of the flight paths and beamstop. This significantly reduces setup time be minimizing the number of times that the enclosure needs to be searched. The other two lasers are available for general use.

• DND staff has assembled three more photodiode detectors for use on the beamline. These are convenient for measuring the intensity from the direct beam at places where space considerations prevent the insertion of an ionization chamber.

• A small translation stage for EXAFS has been installed in the 5BMB hutch. This gives open loop motor control over a small breadboard. (Either a 6x6 or 8x8 inch breadboard will fit the device). The range of motion is approximately 12 mm in both the horizontal and vertical planes. There is a maximum load capacity of about 10 pounds so any sample cell mounted to this device should be below this weight. Please contact the DND staff if you have any questions regarding this stage.

• Each year, DND undergoes a program review with the Advanced Photon Source. During this time, DND must present a synopsis of the work that has been performed on the DND sector. Last year, several researchers provided abstracts on their work which greatly assisted the program review since the review committee could read about the work on our web page prior to the review. While all researchers are encouraged to do this again, Northwestern University is requiring all Northwestern researchers to submit abstracts as a condition of their beamtime. So, if you are from Northwestern and have not submitted an abstract for this year, you must do so prior to running any experiments after the current run or time will not be granted.

• Transportation concerns of chemicals and samples is gaining higher visibility here. APS has reminded all of the CAT's that all hazardous materials that come in and out of the APS must be transported in accordance with Department of Transportation regulations. Materials can either be shipped by a commercial shipper who will package the materials according to DOT regulations, or in certain limited instances, a user may transport the material using the DOT Small Quantity Exception allowance. Certain materials (e.g. radioactive materials, infectious agents, compressed, liquefied or poisonous gas, or explosive devices ...) can not be transported on the Argonne site by users even if they are allowed by the DOT Small Quantity Exemption Allowance. This allowance limits the amount of material per container to 30 gm of solid or 30 ml of liquid for most of the allowed categories. Email dtkeane@nwu.edu if you need help in determining how to transport your materials here.

• Installation of the mirror tanks into the 5BM and 5ID beamlines is continuing. Currently, the tanks have been positioned in place. Reintegration of the vacuum systems and realignment of the 5BMD monochromator will begin today. The mirrors will not be installed at this time since there are still several wiring and mechanical issues with the benders that need to be resolved.

• The Card Key system on the laboratory and office doors has been activated. There apparently are a few problems with some of our user badges, but the APS should be able to resolve these rather quickly. In addition to the DND office area, mechanical laboratory and chemical laboratory, there is now card key access on the door between the Building 432 truck lock and the compressed gas storage area. Consequently, you no longer need to prop the door open when reentering the facility with gases.

• The soller slits on the powder diffractometer has been outfitted with a tilt stage so that the slits can be better aligned. During previous powder diffraction experiments, slit misalignment was suspected in causing a drop in diffracted beam intensity.

• Staff has constructed a robust holder for the MAR CCD camera when it is not attached to its base and sitting on the rail system. The detector mounts on our existing 1" rail system using pillow blocks to securely mount the system to the rail.

• DND staff has looked into the safety concerns regarding use of the Class II laser diodes for alignment. No special safety measure are required for their use other than prohibiting "horse play" with them.

• During the last run, the safety shutter on 5ID occasionally would not open. The APS has just finished replacing the actuator which controls the shutter so hopefully the shutter will not have the problem during this run.

• Last week, representatives from Vacuum Generators installed the monochromator that will be used for 5BMC. The monochromator was installed in the 5BMA beamline. After installation, VG and DND verified that the monochromator met the design mechanical specifications.

• The Card Key system for the DND office area as well as the mechanical and chemical laboratories has been installed. Activation of the system is pending some additional programming work that the APS will do to control the doors. The system should be activated prior to the beginning of next run.

• DND has ordered several Fresnel zone plates from the APS for focusing/microfocusing on the 5ID beamline. The APS has been working on developing this technology for several years and DND is fortunate to be able to take advantage of their work. Several different focal lengths have been ordered and the APS is currently working on the best way to accommodate our request.

• DND has taken receipt of three Class II laser diodes with tilt stages to be used for alignment purposes on the 5ID and 5BM beamlines. These diodes will be available after DND resolves any laser safety issues that Argonne may require.

• DND has also taken receipt of a vertical and horizontal sample translation stage for use with EXAFS set ups. This stages allow a motorized motion of 12 mm in the vertical and 12 mm in the horizontal planes. The motor control is through a manual control box rather than computer control. This method was chosen to provide a more portable method for performing sample alignment since the stages can be taken from one enclosure to another and do not require reintegration into the control system.

• In addition to installing the mirror tanks in the beamlines, DND staff is also concentrating its design efforts in completing the radiation shielding for the ventilation system as well as the transport that will carry beam through 5BMC into 5BMD. The current design for the transport poses some interesting "challenges" for operating in 5BMC. The shield wall for the transport is located approximately 12 cm (4.7 in) away from the center of 5BMC beam. Sample cells and stages for EXAFS and powder diffraction should be designed with limited space in mind.

• The APS is currently in a shutdown period. At present, all of the optics have been removed from the 5BM beamline prior to installation of the mirror tanks and second monochromator. At present, DND staff and representatives from Vacuum Generators are currently installing the 5BMC monochromator into the 5BM beamline. DND staff is also resolving some minor issues regarding the design of the mirror benders during this time as well as wiring the internal mechanisms. The second goal for this shutdown period is to install the mirror tanks in the 5ID beamline. Currently, shielding has been removed from the 5ID transport to accommodate the upgrade.

• The MAR CCD was used for a variety of experiments during the last run. These include small molecule crystallography, small angle scattering, fiber diffraction, and protein crystallography. While all of the data has not been analyzed yet, the detector has so far been able to collect data. In fact during July, DND collected over 20,000 images with this detector. The availability of the MAR CCD system is now one of the determining constraints in scheduling. It had nearly 100% utilization last run and will have a 100% utilization in the next run.

• The schedule for the August-September run has been posted. The due date for submissions for the October-December run is 22 August 1998. On our WWW form, you can specify acceptable and unacceptable dates for beamtime. We look at these very seriously when we schedule and must insist that you use this medium in order to inform us of those dates as well as special experimental requirements. This form serves two purposes. First, it informs us of any scheduling constraints, and collects the constraints from each of the three institutions under one process. Second, it starts our SAFETY APPROVAL process. We are required to perform certain reviews PRIOR to your arrival at the APS.

• APS has reminded all of the CAT's that Argonne prohibits the transport of compressed gases or cryogenic fluid in private automobiles anywhere on site. This stems both from safety concerns and Department of Transportation regulations. As DND staff currently understands the policy, cryogenic dry shippers can be carried in private autos but any cryogenic liquid must be shipped through Argonne Receiving. This mostly affects our users who are performing protein crystallography that need to transport and store their samples at cryogenic temperatures. Since DOT fines can be as high as $25K per incident, APS and DND management is taking this concern extremely seriously. If you have questions regarding this, email Denis Keane at dtkeane@nwu.edu. For now, come to the APS with a dry shipper or ship your samples in advance of your arrival.

• During the last run, time was set aside on the insertion device in order to evaluate CCD tiles to be used to construct a special purpose SAXS/WAXS CCD system. The results from this test were promising and DND members are currently trying to formulate a recommendation on whether or not to procure the system from the one vendor who participated in the test.

• DND is currently making improvements to the alignment tables for the small angle scattering camera. Staff will place each end of the transport under a rotary bearing so that the end can be independently adjusted. DND has also been experimenting with different photodiodes in order to place a photodiode on the beamstop for small angle scattering. We have had some success machining down commercial diodes to the appropriate size. We hope to have one of these in place on the small angle scattering instrument for the next run.

• New rates are applicable for the Argonne Guest House for all APS Users. There is a Quad Room which contains four bedrooms (two rooms have two twin beds in them; so the room has a total of 6 beds).
  The quad rates are

  • 4-7 days: $135/night
    
  • 1 week: $120/night
    
  • 2 weeks: $110/night
    
  • 3 weeks or more: $100/night

• The rate for a single room is now $47.50 a night. These rates are based on availability and require APS Users to identify themselves when they register. An APS User badge is satisfactory identification.

• Operations are continuing on 5ID and 5BM. The MAR CCD is currently running on the bending magnet at energies up to 70 keV. The CCD comes with a base unit which contains two sets of slits, a shutter, and a small goniometer for rotating the sample. The built in slit system and shutter provide adequate absorption to stop the radiation at these high energies.

• There is a scatter source somewhere in the CCD's base that produces powder diffraction rings if the beamsize is larger than ~ 0.2 x 0.2 mm. There is no evidence of large numbers of "zingers" (saturated pixels) hitting the CCD chip. This was one concern in operating the detector at these high energies. DND Staff has also tested the external shutter interface on the CCD controller so that an external shutter can be used with the detector when it isn't possible to use the base unit.. The powder diffractometer is currently running on 5ID. The data resolution and flux is higher than what has been achieved on the bending magnet line.

• Staff is currently working on the schedule for the August run. The schedule will be completed by early next week.

• DND has beamtime set aside next week for performing CCD detector trials in 5IDC. One of the possible vendors has pulled out of the trials. The remaining vendor will bring several CCD systems to test.

• DND staff has implemented a WWW based method for users to attempt to open the vacuum valves on the BM beamline if the Equipment Protection System (EPS) closes one of the valves. Occasionally, a vacuum "burp" occurs in the beamline and the protection system responds by isolating the section of the beamline with valves. Once the "burp" clears, the valves remain close. The WWW page that has the status of the EPS system now has a link which will attempt to open the valves and restore the beamline to operational status.

• DND has negotiated a corporate rate at the Argonne Guest House for Northwestern employees who will be using DND-CAT facilities. Users should make reservations well in advance of their stay, identify themselves as DND-CAT members and ask for the corporate rate for Northwestern University. You will have to reiterate this again a check in and show your University ID in order to have the corporate rate.

• Operations are continuing on 5BM and 5ID. Researchers from DuPont are currently running EXAFS experiments on 5BM and crystallography experiments (including multiple wavelength anomalous dispersion measurements) on 5ID.

• DND Staff is in the process of updating the online directory on our WWW site. JerrieLea Hopf is coordinating our records with those of the APS. So, please check the directory to insure that your contact information is correct. If it isn't, please email JerrieLea at jlhopf@nwu.edu.

• John Kulpin was promoted from Sr. Materials Research Technician to Research Engineer effective June 1, 1998. John is currently working through the undergraduate x-ray diffraction labs at Northwestern University in order to become more familiar with the experimental techniques on the sector.

• The TDC (time to digital converter) for the wire detection system has been sent back to Struck for repair. The module still occasionaly halts during data collection.

•  Assembly is continuing on the 5BM and 5ID mirror tanks prior to leak checking.

• 5ID became operational on Friday 22 May 1998. Operations have been continuing ever since. User groups have reported stable beam operations during standing wave measurements, and protein crystallography measurements. During the shutdown, APS realigned an aperture in the DND beamline and the undulator beam is apparently striking the first crystal of the monochromator lower than in previous runs. This has effectively shifted our energy range upward. During previous runs the energy range on the ID was between 4 and 15 keV. Currently, the energy range is between 7 and 18 keV. There are several experiments during this run which can take advantage of the extended upper energy range, so we are leaving it alone for now. DND is in the process of performing basic stability checks on the beamline during the DND beamtime. Staff was unable to perform basic checks during the first week of the run due to problems with the safety shutter. These problems have been repaired.
   
  

• The MAR CCD was delivered last week. The CCD chip is a defect free chip and is currently being used on 5ID.
   
  
• Due to the time required to bring 5ID operational, staff has been unable to incorporate quick scanning EXAFS into the beamline for the current run.
   
  
• Staff is currently setting up the EXAFS setup in 5BM. After running some standards, staff will revert the setup to one last tomography experiment during the night shift to maximum the use of beamtime. User operations for EXAFS will continue on 3 June 1998 at 8:00 AM.
   
  
• Contractors have begun installing the Card Key system in the DND office and LOM areas. As user operations increase, balancing access with security is becoming a larger concern. The Card Key system will allow users to use their APS badges to access the DND laboratories and offices.
   
  
• The manual beam shutters in 5IDB and 5IDC have been verified with synchrotron beam. However, the APS Personnel Safety System (PSS) group discovered a few bugs in their logic code which will cause the PSS system to go into a fault state if the shutters and the APS online/offline state are not changed in a particular order. Consequently, for the present time, only DND staff members should operate these shutters. This bug does not affect safety in any way.

• 5ID has effectively been down for the last two days due to problems with the operation of the APS safety shutter as well as APS calibration of the x-ray beam position monitors. The APS Personnel Safety Systems (PSS) group is diligently working on the shutter problem. Since the entire x-ray delivery system from the ring to the DND beamline was removed, these calibrations were necessary to provide feedback on the x-ray beam positions. The APS work has delayed work that DND staff must perform prior to user operations. Consequently, DND user operations are being postponed 8 hours from 8 AM, 21 May 1998 to 4 PM, 21 May 1998 so that DND staff can insure that the crystals are aligned, perform basic calibration measurements and gather information about the monochromator stability. The user group that is affected has already been notified. Currently, no other user groups should be affected by this change.
   
  

• The current tomography Experiments on 5BM are continuing. Staff has implemented several changes to the system in an attempt to improve the reliability of the CCD system that is running under Windows 95.
   
  
• The PSS group was able to open the 5ID shutter at 9:00 PM on 21 May 1998. APS completed the radiation certification of the manual beam shutters in 5IDB and 5IDC by 10:30 PM. While the PSS group still needs to perform more work on the safety shutter, users in 5IDC and 5IDD can now set up their experiments while testing is being performed in 5IDB.

• Last week, DND staff reinstalled the x-ray generator into the 5IDA enclosure. Using the x-ray beam, staff was able to measure the 30 hz instability in the monochromator mechanism using double crystal rocking curves. Staff made changes to the design (e.g. stiffening components) and was unable to measure any instabilities at 30 Hz. The monochromator was sealed on Friday 15 May 1998 and the crystals returned to cryogenic temperatures prior to the start of beamline operations.
   
  

• The APS started operations on 18 May 1998. While the APS initially had some difficulty with the shutters on 5ID, they were finally able to keep the shutter opens. Over the past two days, the APS has been steering portions of the synchrotron beam in an attempt to measure heat load effects on the replaced 5ID collimator. APS was required to steer the 5BM beam around to the point that operations on 5BM have been significantly curtailed over the past two days. As of Monday night 18 May 1998, staff was able to begin alignment of the 5ID monochromator using a recently installed florescent screen downstream of the monochromator. Use of this screen has significantly eased the alignment procedure. During DND's alignment tests, staff determined that no significant undulator radiation was being delivered onto the optics in the 5ID enclosure. This was reported to APS and APS has discovered that their x-ray beam position calibrations are no longer accurate. On Tuesday evening 20 May 1998, a clipped undulator beam was delivered downstream into the 5IDB enclosure.
   
  
• Currently, the beam is still missteered. Staff will continue to work with APS to insure that the beam is properly aligned before the beginning of user experiments.
   
  
• Radiation shielding verification of the 5IDB and 5IDC manual beam shutters is scheduled for Thursday 21 May 1998. Prior to these verifications, the shutters are being kept open.
   
  
• DND staff will provide the number of available days for beamtime for the 1998-4 run to the member institutions by the end of the week.
   
  
• Fabrication of the 5BM white beam transport is continuing. An update from the Argonne Machine Shop indicates that they are currently welding portions of the shielding. The support stands are complete. Staff needs to coordinate with the Machine Shop to have the pieces delivered and painted.

• The APS has finished reinstalling the front end beam delivery system to 5ID. All APS work is now complete. The 5ID beamline on the DND side has been reintegrated and vacuum checked. Now that the APS is finished with their work, staff will resume working on the 5ID crystal cage assembly. Staff has written software to allow continuous counting of our scintillation detectors reliably at a sustained 1000 Hz rate in real-time. Staff will use this new capability during the tests of the 5ID mono prior to the start of operations on 18 May 1998.
   
  

• The APS has a new experimental safety approval form that requires users to fill out information regarding a subject category for their experiment in addition to a funding source. DND staff will shortly make these changes to our on-line beamline request form. Request for 1998-4, the run beginning 3 August are due 1 June 1998. Special mode requests for the APS are due 18 May 1998.
   
  
• The APS has reverified the Personnel Safety System on both 5ID and 5BM. Reverification is scheduled to occur every six months. This reverification has delayed some of the DND work in 5ID since hutch access is limited during these required verifications. The switches for the Manual Beam Stops in 5IDB and 5IDC were verified at this time.
   
  
• Staff has help discussions with MAR USA regarding the high energy capabilities of the MAR CCD detector. The vendor believes that the phosphor used in the CCD may not perform well at high energies. If the photons are not stopped in the phosphor, then they can continue on to the CCD itself where they will greatly increase the number of "zingers" that show up in the pattern. The vendor believes that the data may become unusable before any damage to the CCD would occur. At this point, DND will still attempt to use the detector at high energies during the next run. However, staff will ramp up the energy from 20 to 65 keV in order to determine the safe working energy for the detector.
   
  
• A power outage affected Argonne National Laboratory on Thursday 7 May 1998. This outage resulted in a complete power shutdown at the APS for approximately three hours. Staff has restarted all of the beamline systems.
   
  
• The computer interface on the BM Equipment Protection System has been upgraded to allow the data collection system to access whether or not the APS shutters are open or closed. This upgrade will also improve the logging of the beamline systems. The current APS software interface only informs the systems as to whether or not the front end shutters are open and closed. Also, the APS and DND staff have verified the connections to the remote shutter interface on the 5ID line. This interface is similar to the remote shutter interface on the 5BM line which allows the beamline control systems to open and close the APS shutters.
   
  
• The APS PSS group has informed DND as to the safety requirements for the 5IDD mezzanine and the split beamline for 5BMC. In 5BMC, a minimum of an 8 foot high barrier is required in order to split the enclosure into two zones and a six foot high barrier is required in 5IDD near the doorway that opens on to the mezzanine.
   
  
• The APS has posted the schedule for the October run. This schedule is anticipated to be a typical template for future runs. The APS plans on performing machine studies for two days every two weeks. These will occur on Monday and Tuesday. On the week where APS is not performing machine studies, APS will take one shift on the Tuesday for maintenance. While it initially appears that the APS is taking more time, these changes are made in conjunction with longer operating runs and less time between runs. APS is also planning on beginning testing of top off mode in the May/June run. This mode will attempt to keep the current in the storage ring at a near constant level by making many small injections of charged particles into the storage ring. There are several concerns for the user community for this including beam stability. In order to facilitate this change over, APS is planning on switching the storage ring back to electron operation before the the December shutdown to improve the injector reliability.
   
  
• APS is working on a proposal to Argonne to allow the US Department of Transportation's small quantity exception for hazardous materials to apply to the Lab. This exception would allow users to transport SMALL quantities of materials that are properly packaged in their private automobiles. This is currently NOT in place. No hazardous chemicals are allowed to be transported in private automobiles on the Argonne site.
   
  
• Staff is currently working on designing the internal wiring for the 5ID and 5BM mirror tanks.
   
  
• A larger refrigerator has been installed in the DND meeting area for food items. The water cooler has been upgraded so that it dispenses both hot and cold water (The hot water is suitable for making teas, soups etc...).
   
  
• The 5BM mono cooling system has been cleaned out. An in-line filter has been fitted in the system to allow filtering of the system when the beam is not in use. The filter has a manual bypass so that filter can be easily removed from the loop during operations.

• The APS has reassembled the front end beam delivery system on 5ID. APS is currently baking out that section behind the ratchet wall. APS and DND staff are currently in the process of reinstalling the portion of the DND beamline that needed to be removed in order to perform the repair. Once all of the components are installed and surveyed. DND staff will reintegrate the vacuum system.
   
  

• Staff has completed the installation of the manual beam stops in 5IDB and 5IDC. The APS plans on wiring the personnel safety system (PSS) switches for these stops next week. APS and DND are planning a meeting to take place next week to finalize details on commissioning these stops with beam.
   
  
• DND has had several meetings with the APS in order to finalize specifications for allowing limited access zones for 5BMC and 5IDD. In order to properly work in these enclosures, they need to contain an interior PSS zone so that portions of the enclosure do not require a search each time the enclosure is accessed.
   
  
• Staff has been working with the APS and Larry Rock Automation Associates on the design of the DuPont mezzanine in 5IDD to insure that that the mezzanine and staircase design meets OSHA safety standards.
   
  
• The mirror tanks and stands for the 5BM and 5ID beamlines have been delivered by Larry Rock Automation Associates. These systems are currently undergoing receipt inspection.
   
  
• DND has contracted with Larry Rock Automation Associates to design a sagital crystal bender for the 5BMD beamline. This will allow horizontal focussing of the x-ray beam to increase the flux on sample in excess of one hundred. However, the trade off with focussing is that the horizontal divergence of the beam on sample will be about 2 mrad (0.11 degrees) .
   
  
• Staff has begun experimenting with directly reading the encoder position on the monochromator . Staff has designed and built a receiver box that takes the input from the encoders and creates signals that is suitable for use with experimental counters. The intent of this work is to allow the monochromator to continuously move at various speeds and be able to synchronize downstream data collection electronics with the beam energy.
   
  
• Staff is also in the process of installing a water filter on the high pressure side of the monochromator cooling system.
   
  
• A gear head has been ordered for the Phi drive on the four/six circle diffractometer. This gear head will increase the resolution of the phi motor. Staff also anticipates that the gear head will improve the motion stability on this axis.
   
  
• "Kitchen" cabinets have been installed in the coffee area of the DND meeting area. The cabinets replace the single table that held the coffee pot. JerrieLea Hopf is looking into reorganizing the space so that the whiteboard can be reinstalled on the opposite wall.
   
  
• DND has taken receipt of a manual for the Maestro software used to control the EG&G Ortek multichannel analyzer card.
   
  
• The MAR CCD detector is due to be delivered during the next run. Staff is currently discussing with MAR Research the suitability of using this detector at high energies (e.g. 65 keV)

• The beamtime schedule for the next run (1998-3) has been posted. Proposals for the next run, 1998-4, which starts 3 August 1998 are due 1 June 1998. If you need a special operating mode from the APS (e.g. a special bunch pattern etc...), these need to be at the APS by 18 May 1998.
   
  

• The APS has replaced the collimator in the 5ID ratchet wall and they are currently repacking the ratchet wall with lead shielding. After the shielding is back in place, the APS will begin to reinstall the components in the ratchet wall and in the front of 5IDA. The APS is still investigating the reason for the failure.
   
  
• Researchers from DuPont are currently at DND performing startup operations with the Instron test machine. This unit will be used during the next operational schedule for Small and Wide Angle scattering work.
   
  
• Oxford Instruments is currently borrowing the 5IDD hutch to perform maintenence on liquid nitrogen pumps used by other CAT's. The height of 5IDD provides them with adequate height so the crane can remove the pump from its cryostat.
   
  
• Staff is approximately 90% finished with the installation of the manual beam stop in 5IDB and is working out some final kinks in the design. The APS has postponed validation of the 5ID Personnel Safety System until 4 May to make sure that the 5ID ratchet wall collimator work is complete. As a result, staff has sufficient time to install both of the stops for 5IDB and 5IDC, install the switches for the Personnel Safety System and insure that the stops move up and down smoothly. Staff is also working on the layout for the mirror tank installation scheduled to take place in July.

• The APS has been working diligently to discover the reason why the undulator beam hit the collimator inside of the 5ID shield wall. The APS survey group has been reverifying the alignment of all of the front end components, and a number of components have already been removed to allow access to the collimator and the wall. Staff has reinstalled the x-ray generator into 5IDA to work on the monochromator. As soon as the APS has finished its work on the shield wall, we will continue our work on the 5ID monochromator.
   
  

• Staff has submitted a design for Manual Beam Stops to be installed between 5IDB and 5IDC as well as 5IDC and 5IDD. The APS has approved the design and staff has procured all of the hardware for these stops. Once these stops are in place, under APS Personnel Safety System (PSS) control, and radiation checked, experimenters will be able to access 5IDC and 5IDD when running beam in 5IDB. Experimenters will also be able to access 5IDD when running in 5IDC. Staff is attempting to have these beam stops in place by the next PSS validation of the ID safety system. We anticipate this validation to take place either 27 April or 4 May.
   
  
• Staff has been working on the Phi drive of the four circle diffractometer. During the last run, we found that the resolution of the motion was not as high as the experimenters required. Staff has outfitted the motor with a higher resolution encoder (2000 lines per revolution instead of 1000 lines per revolution). Staff is also looking into procuring a gearbox for this motor to increase the resolution and the stability of motion.
   
  
• All beamtime requests for the May 19 have been received. We are currently working on the schedule for the next run. The schedule will be published early next week.
   
  
• The scientific staff position is still open, DND is still reviewing resumes for this position.
   
  
• The steel for the 5BM White Beam transport has been procured by the Argonne Machine Shop. Fabrication of the transport is continuing. DND Staff has had a meeting with the APS PSS group in order to determine the proper search requirements for the 5BMC station.
   
  
• DND has taken receipt of a Huber goniometer (a 1003 gomiometer) for the six circle as well as a pair of Huber slits that staff will outfit with the HSC-1 Huber Slit Controllers from X-ray Associates.
   
  
• DND has also taken receipt of a watchdog timer board for the Tomography setup. During DND's previous prototyping experiments with Tomography, we found that the CCD control program running under Windows 95 would intermittently fail and there was no way to restart the program without user intervention. The watchdog timer board will allow the main control system to restart the computer so that data collection can continue. In addition, we have installed a program called SAMBA on the beamline control computer. This program will allow the Windows 95 computer to store the CCD images directly onto the UNIX disk.
   
  A few minor notes....
   
  
• Various users have noted two problems concerning the mouse on the 5BMB computer. The first problem has to do with the mouse locking up entirely. Staff has replaced the mouse and the problem has not returned. The second problem has to do with the focus not going from window to window as the mouse is moved across the screen. This is a function of the graphical display and has been traced to the Num Lock key being active. This will happen if the user turns on the Num Lock which is often done to use a graphical calculator. So, if this happens in the future, do not immediately reboot or logout, make sure the Num Lock key is inactive.
   
  
• APS has notified us that the Automated Teller Machine in the lobby of building 401 will now dispense $5 bills. Since the change machine near the vending machines in building 401 also takes $5 bills, experimenters can now at least buy a soda/sandwich if you are here late at night and don't have change. In addition, the APS has notified us that they anticipate to provide 5000 hours of user beam during the next fiscal year.

• The APS is continuing its investigations into the cause of the 5ID failure. The APS has formed an investigative committee that is meeting every Wednesday to go over any new information obtained during the week.
   
  

• DND has taken delivery of eight HSC-1 Huber Slit controllers from X-ray Associates. Each controller can control two motors. These controllers bolt onto Huber slits and provide complete motorized slit control. Orders will be placed for the Huber slits later this week and the staff will attempt to have them available for the next run.
   
  
• The 6 circle Huber goniometer was installed into 5BMB last week. During this installation, staff identified several design changes that need to be made so the instrument can be more easily aligned. The same modifications will be made on the powder diffractometer. The control software (spec) has been integrated into the existing DND control system. Northwestern researchers are currently using the diffractometer to study surface diffraction features from single crystals. Staff has identified several minor improvements that need to be made to the motor drive system. A 1003 Huber goniometer head has been ordered for this setup.
   
  
• The translation stages on the sample spinner for powder diffraction have been fitted with micrometer screws to allow for easier alignment of the stage. The encoder on the sample spinner passed a 24 hour burn in test. For flat plate samples, the encoder will allow us to position the sample to within 0.045 degrees.
   
  
• Work orders have been released to install hazardous and nonhazardous gas cylinder cabinets in the Chemical Laboratory and nonhazardous gas cylinder cabinets on the Experimental Floor. An additional storage rack for flammable gases has been ordered for gas storage outside of the building.

• The APS and DND staff have started working on the vacuum problem on 5ID. All of the components upstream of the monochromator in 5IDA have been removed from the beamline. The APS inspected the inside of the ratchet wall collimator with a boroscope on 31 March. There are clear signs of resolidified molten steel on the inside of the collimator as well as a depression due to the undulator beam. The APS is convening an investigation committee on 1 April to go over the incident and look at data that has been acquired to date. The DND Director has been invited to sit on this committee. In order to perform the inspections, we removed the x-ray tube that we are going to use to study the 5ID monochromator. We will coordinate reinstalling the x-ray tube and continuing our studies with the repair of the 5ID collimator.
   
  

• The Optistat cryostat used for EXAFS studies at liquid N2 temperatures developed a leak in its vacuum jacket. The leak is currently being repaired; however, the Optistat is currently usable.
   
  
• Certified Scientific has delivered a copy of spec that uses the DND motor/actuator interface for our four circle diffractometer. This software is a general purpose diffractometer control program. DND staff has installed the software and has begun testing the software with our 6 circle Huber diffractometer. Hardware has been installed to mount a scintillation detector on the two theta arm.
   
  
• Based on our results taken last week on quickexafs data, DND staff has upgraded the data collection system for this experiment to include a 4 Gigabyte disk for local storage as well as increase the memory used for collecting data in real time by a factor of 8. The software has been updated to record three ionization chambers so that further studies can be performed with a reference foil as well as a sample.
   
  
• The wire detector system has intermittent problems collecting data. We are working on this problem.
   
  
• The theta motor for the powder diffractometer has been repaired and reinstalled. An encoder has been installed on the sample spinner motor for the powder diffractometer. We are currently giving the encoder a long burn in test.
   
  
• Network data traffic was unacceptably slow between the SGI computers on the DND network. APS traced this problem to a misoconfiguration of the APS supplied ethernet switch. The systems are now communicating at their normal speeds.

• The most notable event that has happened lately is that the APS has had to shutdown the 5ID beamline. There is a problem with the beampipe that runs through the shield wall that has resulted in a vacuum leak in our front end. The front end carries the x-ray beam from the storage ring to our beamline. Unfortunately, the APS reports to us that the repair will take several weeks, and the repair will be attempted during the next shut down. Consequently, the current DND schedule for the 5ID line is canceled.
   
  

• An automatic shutter opening algorithm has been added to the 5BM software. The user now has the option of automatically having the APS 5BMA and 5BMB shutters open after a refill. DND is the first CAT to have this feature installed.
   
  
• During the DND beamtime on the bending magnet, we investigated holding the energy of the beam constant while the beam decayed by changing the temperature of the monochromator cooling water as the ring current changed. While our initial results showed that this was feasible, we are still evaluating whether or not this would would be practical to implement. We also worked on taking EXAFS data in a continuous scanning mode (so called QuickEXAFS).
   
  
• The x-ray generator has been placed inside of the 5IDA enclosure so that we can continue our studies on the 5ID monochromator. Replacement pieces have been made in the machine shop.
   
  
• All hardware has been installed to mount a scintillation detector and slits on the 6 circle Huber diffractometer.We will need to reevaluate this mounting arrangement if heavier detectors are used.
   
  
• Last week, we found a problem with the Ge detector system that is being contributed by DuPont. The problem was traced to the amplifier module. We are in the process of sending it back to Ortek for evaluation and repair.
   
  
• The TDC module for the wire detector system has been returned by Struck. Initial tests show that the module is working properly.
   
  
• A representative from Instron is currently at DND assisting the staff as the Instron is calibrated and commissioned.

• On 4 March, members of all the DND institutions participated in DND Technical Meeting at Northwestern University. The equipment and scientific needs in five major areas of DND research were discussed in focus groups. These areas included EXAFS, Powder Diffraction, Surface Science, Crystallography, and Materials Science.

• In order to better control access to the DND radioactive sealed sources, the key for the sealed source drawer is located in a keysafe. If you need to use the source, you must be authorized to do so and obtain the combination from the Director We will periodically change the combination on this keysafe to minimize unauthorized use. Sources must be returned after use and must not be left unattended without proper postings.

• The new sample spinner for powder diffraction has been commissioned and is working well. We will make a few changes to it in order to make it easier to align. This spinner will spin capillaries as well as rock flat plates. The mounting arrangement is a standard IUCR (i.e. Huber) mount.

• During the current run, the gearbox that drives the theta motor on the power diffractometer failed. We are sending the gearbox back to the vendor for repair and ordering a spare. This currently limits the use of the diffractometer to capillary samples. Flat plates can be accommodated as well with advanced notice since the sample spinner mentioned above does have some angular control.

• We have ordered SPEC from Certified Scientific Software to control the diffractometers on the beamline. We had a meeting with the APS on 6 March to discuss the proposed mezzanine structure in 5-ID-D. The APS is looking at the proposed design to make sure that all safety issues are considered.

• A new motor control rack was installed above 5BMA to control all of the servo motors in the BM first optics enclosure. This work was done in preparation for staging mirror tank installation.

• We are currently receiving resumes for the new scientific staff position.

• We installed hardware to support our monochromatic vacuum slits in 5BMB. We have three of these systems in house.

• The cryopump for the 5ID monochromator was overhauled as part of its regular maintenance cycle. During the overhaul we found that the impeller was scraping against the inside of the pump casing. Since this could have introduced vibrations into the cooling lines that would have affected the ID mono stability, we did not make any changes to the ID mono during the shut down. We did open the monochromator and performed a visual inspection. During the DND beamtime, we found that a large part of the "instability" in the monochromator is due to an approximately 30 Hz ripple that modulates the intensity. We will continue to investigate solutions to this problem during the DND beamtime days left in the current run. Over the weekend, the burst disk on the cryopump failed. The burst disk was replaced and the system was brought back to operational status.

• The DND sector underwent a complete power shutdown over the weekend on 2/21 for twelve hours. The staff is still bringing up and recalibrating our systems.
   
  
• The Advanced Photon Source is in the process of upgrading our computer network closet. The new upgrade will provide DND with 24 switched 10 Base T Ethernet and 6 100 Base T Ethernet connections. The switched 10 Mb/s links will feed the office area. While we investigate the best way to use this extra capability, we have placed orders for equipment that will bring one of the 100 MB/s links to the experimental floor. We anticipate that this capability will be in place for the run beginning 9 March 1998. Currently, we just have one 10 MB/s link running to the experimental floor. This extra capacity should significantly increase the data transfer throughput from the experimental floor to the LOM and the rest of the world.
   
  
• The time frame generator for the wire detector system has been sent back to Struck for repair. This only affects the use of the 2D wire detector.
   
  
• The first order has been placed with Argonne Central Shops to begin procurement of the 5BM shielded transport. This transport will bring the beam from 5BMA into the 5BMC and 5BMD stations.
   
  
• We are currently building a sample spinner for the powder diffractometer. All parts have arrived and the staff is performing fit up work.
   
  
• Cable Tray has been installed in the 5IDB and 5IDC enclosures.
   
  
• Representatives from Blake Industries are currently here aligning the diffractometer for the surface science instrument.

DND-CAT has come a long way from a paper proposal to the APS to the facility it is now. We were fortunate to have Joe Georgopoulos as our director for the birth of the project. I know that I speak for the entire staff in saying that we will all miss Joe and hope that he comes back to visit. Everyone here at DND wishes Joe the best in his new career. Now, we must continue to move forward and develop our facility to make the best use of the high brightness and high energies x-rays that the APS offers us.

This is an exciting and busy time at DND. We have in excess of one hundred registered users and we have engaged in a wide variety of experiments including crystallography, powder diffraction, small angle and polymer scattering, EXAFS, etc... We have begun our first experiments on the undulator and can now routinely provide x-rays up to 90 keV on our bending magnet. Also, we are still building. We have not yet realized our goal of splitting the bending magnet beamline. When that is completed later this year, the output of our bending magnet stations will double. We are also staging a major upgrade to insert focusing x-ray mirrors on the undulator and one bending magnet beamline. We also plan on another upgrade to incorporate sagittal focusing on the bending magnet beamline and finish a number of smaller projects. We also continue to work with the APS on systems which benefit the entire APS community. For example, on our bending magnet beamline, we are currently testing a prototype system to allow beamline computers to open APS controlled x-ray shutters. In order to help with these and other projects, we are searching for another beamline scientist to work in our group.

While the scientific staff at DND has its own projects, most of our efforts are dedicated to providing a facility which meets the scientific needs of our members. In order to do this, communication between the staff, our Management Board, and our membership is very important. In order to facilitate this, DND-CAT is planning a Technical Meeting at our APS facility on March 4 1998. Each DND member organization has a representative which is coordinating efforts at that institution for this meeting. Feel free to contact us if you need help in locating your coordinator. I hope that this meeting has a large turnout since it provides input as to the direction that DND takes.

I look forward to seeing/meeting you at our March 4 DND-CAT Technical Meeting.

John Quintana

As I close this chapter of my career and move on to new challenges, I realize that I have been privileged to be associated with DND. This project started with all the right elements for success in place, thanks to the vision and guidance of Jerry Cohen, Dean of Engineering at Northwestern and Bob Johnson of Du Pont (now retired). Their vision was later shared by Phil Rudolf of Dow. DND is probably the best conceived and managed Collaborative Access Team at the APS.

The second element of success is our staff. Without a dedicated group of people with a sense of mission and virtually unlimited reserves of energy and motivation, DND would not be the first CAT outside Argonne to begin operations or the CAT with by far the largest user base. I will miss the warm and productive environment that I shared with John and Denis, Alan and John, JerrieLea and Mike. With John at the helm now, DND operations are about to make the transition from adolescence to adulthood. I wish them all success.

Finally, DND has the best users at the APS! You were the first to start producing exciting science and your number is still growing by leaps and bounds. It has been a pleasure and a privilege working for you.

My best regards to all
Joe Georgopoulos

Reservations for the March/April (Operating cycle 1998-2) operations schedule are due on or before January 16, 1998.

Access the future schedules and the reservation form and then submit your reservation electronically.