Jefferson Lab Weekly Briefs March 11, 2009

Jefferson Lab Weekly Briefs

March 11, 2009

12 GeV Upgrade

The construction contractor for the Central Helium Liquefier building addition is finalizing administrative submittals to obtain approval for onsite work. The first phase of the work is relocation of a fire hydrant and expansion of the asphalt pavement on the east side of the existing CHL building. Phase 1 work is scheduled to start in April and has a one-month duration. Upon completion of Phase 1, the Cryogenics Group will relocate the helium tube trailer to the east side of the CHL building.


In Hall A, after losing more than three days of beam, experiment E06-014, Precision Measurements of the Neutron d2, resumed stable production running and is expected to reach its goals with the four-day extension to March 16.

Hall B continues to run the eg1-dvcs experiment using an extremely well-performing polarized target. The extension of the run until March 16 will allow experimenters to collect the data expected for this run period. The CLAS collaboration had a very successful meeting on the physics program of the upgraded CLAS12 detector for the JLab 12GeV Upgrade. About 120 people participated in the meeting, discussing exciting physics perspectives for CLAS12, the upgraded CLAS detector for 12 GeV. Representatives of the French, Italian and European funding agencies presented talks on their support of the JLab upgrade.

The Spin Asymmetries of the Nucleon Experiment in Hall C has completed measurements of scattering asymmetries with the proton target polarization oriented perpendicular to the beam. For both 4.7 GeV and 5.9 GeV running, the experiment obtained about 75 percent of the statistics planned in the proposal.  The remainder of the running time will be dedicated to running with the target polarization parallel to the beam at both 4.7 and 5.9 GeV.


Last week, the accelerator started off well, but the performance was affected later by some magnet box supplies and the beamline vacuum at 1L04. Three box supplies each tripped off a couple of times during the week. On Friday, the passes for both Halls A and C were changed and so was the Wien angle. On Sunday, the vacuum at 1L04 started to deteriorate. Early Monday, the vacuum at 1L04 was getting worse and beam delivery was interrupted. As of Tuesday morning, the recovery of the vacuum was still in progress. 

Free-Electron Laser (FEL)

FEL staff had a good week of running despite a slow start due to snow days. Staffers provided light in the user labs on several days, doing some demonstrations of beam profiles in acrylic. The team continues to acquire interesting mirror performance data. The director of the Office of Naval Research was hosted for a visit on Friday.

Theory Center

A new paper (arXiv:0902.4256 [nucl-th]) explores quark-hadron duality in semi-inclusive pion electroproduction on proton and neutron targets. Using the spin-flavor symmetric quark model, ratios of pi+ and pi- cross sections are computed for both unpolarized and polarized scattering and realizations of duality in several symmetry-breaking scenarios are discussed. The model calculations allow one to understand some of the key features of recent JLab data on semi-inclusive pion production at low energies.

JLab's Safety Numbers

65 Days since Last Recordable Accident (JLab record: 331)
182 Days since Last Lost Workday Accident (JLab record: 676)

JLab Calendar of Events

March 11: JLab Colloquium in CC auditorium, 4 p.m.
March 12-13: Spin Structure at Long Distance Workshop
March 17: Virginia Statewide Tornado Drill
March 25-27: International Workshop on Positrons at Jefferson Lab
April 14: 12 GeV Upgrade Groundbreaking
April 14: Science Series Lecture: Hurricane Hunting
May 2-5: APS April Meeting in Denver
May 25: Memorial Day holiday, lab closed

Environment, Safety, Health & Quality

An incident involving an undocumented work restriction was recently investigated. A worker with a heightened sensitivity to certain fumes was transferred to another department. He and his previous supervisor had an informal agreement that if fume exposure caused issues, his work would be relocated out of the affected area. This occurred approximately once every three months. Previously, the worker had been verbally instructed by a physician to avoid these types of fumes; however, there was no formal work restriction issued by either this physician or by JLab's Occupational Medicine Department.

The undocumented medical restriction information was not made known to the new supervisor. Subsequently, fume exposure occurred, which resulted in a work-related medical issue. The investigative team solicited feedback for corrective actions; these actions address issues such as employee and supervisor feedback to Occupational Medicine staff of emerging medical conditions, as well as Occupational Medicine staff followup on emerging issues during each employee's triennial physical examination.

Please remember that safety is everyone's responsibility; provide feedback to both your supervisor and Occupational Medicine if you have emerging medical issues and obtain the necessary restrictions if they will impact your work.

Computing and Networking Infrastructure (CNI)

CNI Maintenance Period Set for Tuesday, March 17
The CNI group is currently planning a maintenance period for 5-10 p.m. on Tuesday, March 17. During this time, e-mail, home directories, group areas, etc. will be unavailable while the central file server is upgraded. Other items are currently being planned, so continue to check the webpage for additional updates.

Default Settings for Windows Printers to Change
Recently, it was discovered that the default settings for some Windows printers were incorrect. A change announced last year to make black and white, double-sided printing the default was not applied to all printers. Beginning March 17, the Computer Center will work through existing print queues to correct this. You will still be able to print in color, or single-sided if desired, but you will need to explicitly select these options when you submit a print job.

E-mail Outage and Reconfiguration Begins Friday, March 20, 10 p.m. Through 3 p.m., Saturday, March 21
The IT division's CNI group will perform a major reconfiguration of users' e-mail, requiring an outage. The outage will begin Friday, March 20 at 10 p.m. and last through 3 p.m. on Saturday, March 21. No e-mail services will be available during the outage. E-mail sent to JLab addresses from offsite will queue and be delivered after the outage. Reading or sending e-mail from within JLab (including webmail and offsite computers configured to use JLab's e-mail servers) will fail during the outage.

The location of e-mail folders is being changed. Currently, JLab account holders have e-mail folders that are stored in their home directories (/home/user on Unix or J: drive on Windows). The reconfiguration will move these folders out of account holders' home directories and place them on a standalone, isolated file system. Account holders will not have direct access to this new file system. All access to these folders will require an IMAP mail client (i.e. Thunderbird, Pine configured as an IMAP client, etc). Further information about this reconfiguration will be available on the CNI group web page as the date approaches. Alias Change
Some staff and users at JLab use the shorthand to login to the central servers from on and offsite. Starting after the March 17 CNI maintenance period, will resolve to from offsite instead of as it is now. After that time, users will need to login to instead. A similar change to the alias from onsite is also being tested. Start specifying the machine you want to login to, since the alias may not point to what you expect in the future.

Mathematica 7 Now Available
The latest version of Mathematica is now available for use at the lab. On any of the central systems (jlabl1, etc.) you can type 'use mathematica/7' to add the latest version ot your path. Then you can run version 7 by just typing mathematica as usual. This version will become the default after the April 7 maintenance period.


Pager System Upgrade
JLab is replacing its aging pager system to improve availability and reliability. A graded distribution of pagers for the new system will take place Monday, March 23Thursday, March 26. Pagers currently used with the old system will no longer receive messages after March 31. Details about the transition to the new service can be found here.

Come and Join the JAG Dog Training Club!
The JAG Dog Training Club will begin training again in April. Come to the organizational meeting on Wednesday, March 18, at noon in VARC Room 72, the BEAMS Classroom. Whether you want to train in puppy kindergarten, basic manners, therapy dog or dog sports, the JAG Dog Training Club is the organization for you! Whether you're the owner of a new dog or puppy, or if you're a serious canine enthusiast or competitor, the club can help you gain the most from your companion dog. Pizza will be served at the meeting, so R.S.V.P. to Joyce Miller, x7163, or to Brian Kross, x7022.

Interested in golf?
Come out and join the Jefferson Lab Golf League. The league will start play March 30 and go through September. Team members play Monday evenings at Newport News Golf Club, starting at around 4:30 p.m. No experience is necessary. If you are interested and would like more information, ask one of the people already in the Golf League or call Danny Machie (x7501). Check out additional details and see who is already in the Golf League at the Golf League webpage.

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