Difference between revisions of "G2p Analysis Minutes"

Revision as of 16:51, 26 January 2011

Minutes of the weekly analysis meetings

1/26/2011: Present : Kalyan, Jixie, Melissa, Alex, Min, Pengjia, Jianping, Karl

• Jixie:

1)The coil will block almost half of the acceptance of one arm for the configuration that the field is 80 degrees with the beam and HRS at 6 degrees. Refer to https://hallaweb.jlab.org/dvcslog/g2p/9 for details. For HRS at 12.5 degrees, only single arm data will be available.

Need to mention this to Doug and Guy. Alan is waiting for the decition to finalize the design for the scattering chamber entrance window.

2)Still waiting for input of beam dump for the Geant4 simulation

• Kalyan: Search for probability of the 3rd arm. Inelastic cross sections have been shown here: https://hallaweb.jlab.org/dvcslog/g2p/5

For 74 degree and solid angle 60 mSr: The elastic Pr rate is about 4 kHz; the total inelastic rate for Pr in momentum range 0.25-0.4 is about 270 kHz.

Need to find out a way to reduce the inelastic rates. Increase the momentum range to 0.280Gev/c may help...

• Jp: About the BCM|BPM of the beam line

• Pengjia: Talked about the target cooling took place at UVA. The

maximum field provided by UVA solenoid is 5.0032 Tesla. He showed some pictures of the solenoid, the microwave generator, the pump system.

1/19/2011: Present : Kalyan, Jixie, Melissa, Karl, Min

• Kalyan : Working on third arm elastic rates. Looking at 2 options,

both on beam left: 1) Bigbite detecting protons at 74 degrees. Issues: manpower to install, no identified power supply and possible issue of overtaxing the power budget to the hall (Ed Folts). Guy may have power supply at Berkely. Jixie will follow up to see if power budget is real problem. 2) A small calorimeter at 42 degrees to be used as electron detector on the platform about 2 m from the can. Pros: simple design, little tech support needed. Cons: rate will be very low. PMTs near target field might have problems. Goal is to have a decision to present at the next collab meeting.

• Jixie: Working on the Geant4 simulation. Has created scattering

chamber and included the UVa target field map. Waiting for more information on the beam dump design. Initial goal is to look at radiation in the hall. Intermediate goal is to look at acceptance blockage by the target coils. Later, will be able to look at physics and issue of radiative tails at low Q2. Jixie will talk to Whitney Armstrong from Temple who created a geant 4 simulation of the target for SANE. Jixie is working with Min on SNAKE. John having difficulty to transfer code from solaris to linux. Will talk to Doug about impact of acceptance blockage on gep (target at 80 deg) for 12.5 degrees scattering.

• Min: Working on the fitting for SNAKE. Also interested to get

involved with the 3rd arm study.

• Melissa: Starting to look at target and detectors.

• All: Discussion of manpower and projects in need of manpower.