Latest Weekly Briefs

Wed, 2017-06-21 17:53

Jefferson Lab Weekly Briefs
June 21, 2017

Physics

Jefferson Lab Published Journal Articles, June 11-17

  • I. G. Aznauryan, V. D. Burkert. "Electroexcitation of nucleon resonances of the [70,1-] multiplet in a light-front relativistic quark model." Phys. Rev. C 95, 065207.
  • P. G. Blunden and W. Melnitchouk. "A dispersive approach to two-photon exchange in elastic electron-nucleon scattering." Phys. Rev. C 95, 065209.
  • Ph. Boucaud, F. De Soto, J. Rodríguez-Quintero, and S. Zafeiropoulos. "Refining the detection of the zero crossing for the three-gluon vertex in symmetric and asymmetric momentum subtraction schemes." Phys. Rev. D 95, 114503.
  • Jeremy Green, Nesreen Hasan, Stefan Meinel, Michael Engelhardt, Stefan Krieg, Jesse Laeuchli, John Negele, Kostas Orginos, Andrew Pochinsky, and Sergey Syritsyn. "Up, down, and strange nucleon axial form factors from lattice QCD." Phys. Rev. D 95, 114502.
  • D. Ho, CLAS Collaboration. "Beam-Target Helicity Asymmetry for γn→π−p in the N* Resonance Region." Phys. Rev. Lett. 118, 242002.

Remember to submit your papers for approval to the Jefferson Lab Publications database.

History Archives Photo of the Week
This week's photo of the week features HUGS students gathering to tour CEBAF 25 years ago on May 29, 1992.

Center for Theoretical and Computational Physics

A new collinear factorization analysis of inclusive deep-inelastic scattering with nonperturbative jet correlators has shown that a novel spin-flip term associated with the invariant mass of the produced hadrons couples to the target's transversity distribution. This provides a hitherto neglected and large contribution to the twist-3 part of the g2 structure function, which can explain the discrepancy between recent calculations and empirical analyses. It also provides an extension of the Burkhardt-Cottingham sum rule, putting constraints on the small-x behavior of the transversity function, as well as an extension of the Efremov-Teryaev-Leader sum rule, suggesting a novel way to measure the tensor charge of the proton.

Facilities Management and Logistics

Limited Access to CEBAF Center F-Wing First Floor on June 24
This coming weekend, Warwick Plumbing & Heating subcontractors will be spraying foam in the Data Center as part of the Utilities Infrastructure Modernization (UIM) Data Center Upgrade project. There will be limited access on the first floor F-wing hallway on Saturday, June 24, due to spray foam hoses. Additionally, a slight odor will be present inside the Data Center likely throughout the weekend (the space will be ventilated for 24 hours after foam is sprayed). It's recommended that staff and Users avoid the first floor of the F-wing over the weekend. If you have any questions or concerns about this work, contact Michele Solaroli, x7751.

Annual Property Inventory Underway
Now through the end of August, Property Management staff members are verifying the physical location and serial number of randomly selected Jefferson Lab tagged property. When asked, Property Custodians must show Property Management personnel the items that they have assigned, at the correct location, and be able to show the tag # and serial #.

Reminders: If a tagged item is going to be put in a different location on-site for more than 30 days, a Movement Request must be submitted to the Property Management section; also, for any tagged item a Property Custodian plans to take off-site, the custodian must apply for and have a fully approved Property Pass or Temporary Property Movement (a loan) for the item.

More information about the property inventory and requirements can be found in the full memo.

Engineering

A Lessons Learned Pressure Systems training session for Design Authorities and System Owners is being held on June 27 at 1:30 p.m. in ARC 231/233. Speakers will discuss recent changes to the ASME Pressure Piping Code B31.3, operator training, and recent experiences in procuring and fabricating systems to the Pressure and Vacuum Systems Safety Supplement.

Preventive maintenance continues for the Electrical Engineering Support department (EES). The RF group performed testing in the Low Energy Recirculator Facility to determine klystron suitability for supporting the soon-to-be-installed C50-13 in zone 1L13. They also completed the removal of the waveguide in 1L13 prior to removing the old cryomodule. The fabrication and testing of control chassis for the Upgrade Injector Test Facility and Linac Coherent Light Source II (LCLS-II) continue. The polarized gun (PGUN) viewer control upgrade, along with cable pulling and termination in the injector, was completed by the Instrumentation and Control group. The Safety System group is supporting the ongoing upgrade to Hall A’s ion chamber system.

A major effort from the Cryogenics department and Mechanical Engineering group continues to close out the design and documentation effort to support installation of the LCLS-II Cryogenics Plants 1 & 2. Progress is good, but it continues to be a challenge to deliver the documentation in time to support the project schedule. Conceptual modeling for Jefferson Lab Electron-Ion Collider Interaction Region magnets continues. Many groups within Engineering continue to work with the 12 GeV project to support efforts to complete the Hall B solenoid and get it delivered, installed and commissioned by the end of the year. Multiple shift operations are being planned to support this effort throughout the summer.

Environment, Safety, Health and Quality

Calibration and Control of Measurement and Test Equipment
 
Measurement and Test Equipment (M&TE) is used for inspections, acceptance testing, data collection, process monitoring, maintenance, repair and calibration of installed facility equipment and instruments to determine compliance to a requirement. Calibration of M&TE is required on a periodic basis to ensure accuracy of readings. Use the following resources to determine how frequently M&TE requires calibration:

  • Manufacturers' instructions,
  • Published standard practices, or
  • Other written instructions if it contains the above information.

Per Jefferson Lab’s Graded Approach Procedure, exceptions to the above requirements are allowed for infrequently used M&TE. If it is used at intervals exceeding the recommended frequency (e.g., a piece of M&TE is only needed every five years, but the recommended frequency is annually), Jefferson Lab does not require that it be maintained in a “Calibrated” state. However, prior to use, M&TE calibration status must be current. Per Jefferson Lab’s Calibration and Control Procedure for M&TE, the owner has the option to make a conscious decision to calibrate the item only at intervals to correspond to actual use.

Computing and Networking Infrastructure

Jefferson Lab Campus-Wide Phone Outage Scheduled for Saturday, July 8
Jefferson Lab’s landline telephone system will be down intermittently on Saturday, July 8, 8 a.m.- 5 p.m. The outage will permit equipment upgrades. Across Jefferson Lab, the outage will disrupt landline telephone services, voicemail and fax machine services. This outage will also affect Jefferson Lab and university phones in the ARC, but not the commercial tenants in the ARC.

To Get Help and Report Emergencies During the Outage:
- Use a cell phone to call 911.
- After you are advised to hang up by the 911 Dispatch Operator, immediately call the Jefferson Lab Security cell phone at 757-342-9868. Advise Security of the 911 call, the nature of the emergency and the location of the emergency.
- Or activate the closest fire alarm box if no cell phone or coverage to alert Security of your issue. (Security will send an officer to investigate; however response times will vary.) And if or when possible, follow up with a call to the Security cell at 757-342-9868 to advise them of the situation.

Inquiries during the outage can be made to Jefferson Lab Security’s cell phone at 757-342-9868. For more information regarding this outage, contact the IT Division Helpdesk at helpdesk@jlab.org or x7155.

Announcements

Annual Electricity Reduction Test Set for June 22
For one hour on Thursday, June 22, Jefferson Lab will reduce the amount of electricity it is drawing from the power grid, as part of a region-wide drill to reduce stress on the grid. For 2-3 p.m., pre-identified work centers will reduce electricity use by turning off or turning down equipment not necessary for critical work or safety. In addition, all employees will be asked to also minimize unnecessary electricity use in their offices and work areas. A Site-Wide Alert message will be sent out notifying the lab community of the load-reduction event and request that pre-identified areas reduce their electrical use, and in general across the lab, unneeded lights and appliances be turned off. For the June 22 test: Those individuals/groups using systems that are electrically power intensive, such as DC power supplies, operations in the Test Lab VTA (vertical test area) or cavity test areas, should plan work such that energy-intensive operations do not occur during the 1:45-3:15 p.m. test period. If this work will be stopped or reduced for the test, these systems should be powered down by 1:45 p.m. At the end of the annual test or an actual event, a SWA message will be sent out. For more information about the electricity reduction test, see the full memo.

TIAA-CREF Individual Counseling Sessions Offered Summer/Fall 2017
TIAA-CREF is offering Individual Counseling Sessions, where you can discuss your personal financial situation with a TIAA-CREF financial consultant on a confidential basis. The consultant will be available at Jefferson Lab on July 27 and August 17 in Support Service Center room 22i to discuss how to help you achieve your financial goals by investing in financial solutions, such as mutual funds, brokerage, life insurance and annuities. To schedule an appointment, call TIAA-CREF at (800) 732-8353, Monday through Friday, 9 a.m.–8 p.m. (ET). See the full announcement here.

Jefferson Lab Calendar of Events

June 22-23: Joint Hall A & C Summer Collaboration Meeting
June 29-30: SoLID Collaboration Meeting
July 4: Independence Day holiday; Jefferson Lab closed

JLab Weekly Briefs is an ongoing publication providing information on the status of safety, accelerator operations, experiments, free-electron laser, reviews, upcoming activities and special events. Deadline for submission is every Tuesday by 10 a.m. Submit new items to: the Communications Office or contact Kandice Carter at x7263.