Dear Colleagues:

As the year 2009 has come to a close it is fitting to take a look back at some of the accomplishments we all have achieved together.

I want to begin by welcoming the new members and several new institutions to the CLAS collaboration. The new additions have made the collaboration stronger this past year as has also been evident in the increased participation at collaboration meeting. The most recent CLAS meeting in November had well over 100 registered participants. 

The 6 GeV program: 

We had an outstanding harvest of publications in refereed journals, 16 in total including 6 in PRL/PLB, 9 in PRC/PRD, and 1 in EPJA. They span the entire physics spectrum from nuclear interactions to hadron spectroscopy and deeply virtual processes. These results could not have been achieved without individuals and groups working together in the run groups and physics working groups. Critical in this process have been the reviewers in the analysis and ad hoc committees who dedicated many hours to help achieve the final results and well-developed papers. Another sign of success is the many invited conference talks and the large number of presentations given by students and postdocs, reflecting their research on CLAS data. 

In coarse of the year we carried out a full experimental program of 34 scheduled weeks with two major run groups: The eg1-dvcs combined two highly-rated experiments to measure the DVCS process with the longitudinally polarized proton (NH3) target, and the single target spin asymmetry for semi-inclusive pion production. The length of the approved beam time made it necessary to subdivided the run into 3 section spanning the period from February to September. The eg6 run combined two highly-rated experiment., both using pressurized He-4 gas, and both measuring processes that have never been measured before: the search for hybrid mesons in coherent neutral eta-pion production, and the DVCS process. A new RTPC had to be built for the detection of low energy recoil alpha particle, that would accommodate more stringent requirements, and new electronics was needed to increase the readout speed by a large factor. While the eg1-dvcs group fully achieved its luminosity goals, and was able to collect additional data on polarized ND3, the eg6 run was scheduled for less than the full amount of approved beam time due to scheduling conflicts, and the commissioning of the new RTPC detector took significantly longer than planned. Still, the anticipated statistics will be sufficient to achieve the primary goals of both experiments. 

The HD-Ice target is being brought back to operation after its transfer from BNL to JLab. A new HD laboratory is nearly ready for occupancy and will house the target components, high field polarizing magnets, and cryogenic equipment.   A new in-beam cryostat is under construction that will allow the HD target operation in CLAS. 

The 12 GeV Upgrade:

The Hall B upgrade with CLAS12 had a very successful year 2009. The first European CLAS12 workshop was held in Genoa, Italy. Many MOU's related to the construction of CLAS12 base equipment were signed with Universities. The DOE Independent Project Review in September resulted in excellent results with no recommendations. The CLAS12 detector is now fully in construction mode. Contracts for the two superconducting magnets, the forward Toroid and the central 5 Tesla Solenoid magnet have both been awarded to a commercial company, and full designs are being prepared. Major detector components for the pre-schower calorimeter (PCAL) and the drift chamber systems have been ordered and received. Construction of the PCAL started early due to the NSF MRI proposal that was approved in 2008. The "clean room" in the EEL building has been restored to its original dedication as a class 10,000 clean room, and is being prepared for stringing the first region 2 drift chamber. Components for the barrel part of the Silicon Vertex Tracker are in procurement, and a first article module is being prepared. As a result of a workshop at Saclay we also decided to enhance the tracking capabilities of the central detector by adding several layers of micromegas.

A broad physics program was approved by PAC30 and PAC32, and PAC34 approved four more experiments to bring the total to 1,139 days of requested PAC time. Due to parallel running this corresponds to about 5 years of experiments. Several experiments require additions to the base equipment, such as the detection of neutrons at at large angles, and  the detection of high energy charged kaons for which CLAS12 in its current implementation is not optimized. Several groups in the collaboration have joined into initiatives to add detectors for high energy kaons and low momentum neutrons. These will be expansive additions to CLAS12 and require cooperation of many groups to raise the necessary funds and to develop the detectors. These and other initiatives reflect a growing involvement of international groups into defining the future directions of the research with CLAS12. This also presents great opportunities for students and young researchers to get involved in challenging hardware and software projects. 

None of what we have achieved in 2009 would have been possible without the effort of many people, from the highly dedicated collaborators and Hall B staff, the polarized target and fast electronics groups, to the effort of the accelerator operation group to provide high quality beam to Hall B. Fittingly, the year ended with a highly memorable end-of-the-run party for which the spokespersons of the eg1-dvcs and eg6 run groups  deserve the credit. 

The Year 2010:

While we cannot be completely sure how 2010 will turn out in terms of funding for research, the signs we receive make me hopeful that we will be able to complete the tentatively scheduled 33 weeks of running g9-FroST and g14-HDIce.  Without question, the 12 GeV upgrade and CLAS12 will play an increasingly important role in our activities this year. Construction and testing of detector component will be in full swing at several institutions. Let us all work together to make sure that 2010 will be a great year for the ongoing 6 GeV program and for our 12 GeV future!  

I wish you all a peaceful and successful year 2010.

Volker Burkert