January 30, 2015 - Mott Group Meeting

Folks,

Let's meet next Friday, January 30th at 1:30pm EST in TL-2236. Some topics are listed below.

In the meantime, the Run 1 wiki has been updated run a chronology of events/logbook entries and the final on-line spreadsheet of runs and on-line results: https://wiki.jlab.org/ciswiki/index.php/Run1_-_January_2015

Blue Jeans and Wiki

Toll Free Phone number: 1-888-240-2560
Int'l Call Phone numbers: http://bluejeans.com/numbers
Meeting ID: 175023762#
Web connection for desktop sharing: http://bluejeans.com/175023762
Wiki: https://wiki.jlab.org/ciswiki/index.php/January_30,_2015_-_Mott_Group_Meeting

Lessons learned from Run 1

1. Small aperture mouts may be impractical. Thin foils on backing on larger aperture mount seemed okay.
2. Replace viewer with either gridded chromox or YAG crystal, and learn how to use video and image tools
3. Make measurement, analysis, data logging as automatic and convenient as possible: Media:DataAnaScreen.pdf Media:DataAnaScreen.pptx
4. Improve or standardize our capability for beam characterization (emittance, momentum, energy spread, bunch length)

Sibling thickness measurement status

FESEM measurements

profile of each target to sample thickness

profiles of 2-3 targets multiple foil locations (tests uniformity + preparation technique)

Sibling list

::0.050 um, 6809-B (done)

0.225 um, 7029-B

0.350 um, 5613-D (changed from A)

0.500 um, 5275-C

0.625 um, 7028-B

::0.750 um, 5134-B (done)

0.870 um, 3057-C

1.000 um, 5385-B

Notes

• FESEM resolution is about 1.5 nm @ 15keV (l=h/p)
• Sibling list of foils used (note, 0.05um foil 12 does not have sibling and both 0.35um foils 8 and 14 have same sibling)
• Images saved as TIFF (highest quality of TIFF, BMP, JPEG)
• ImageJ is free image analysis software hosted by NIH

Rough first analysis of two foils

File:ThicknessAu5134b.pdf

File:Asym vs thickness.pdf

Divvy-up analysis and summary writing

Analysis systematics

Energy and Time Cuts

• Suggestion described here File:ETCut.pdf and take from Grames thesis, pp.56-73

Low and High Threshold

Polarimeter Systematics using "nominal" beam

Deadtime

Beam current

Target position

Beam position : 0.22um(1) and 1um(15)

Dump dipole

Polariimeter Systematics using "off-nominal" beam

PITA

Spin Dance

Spot size

Cavity phase

Beam measurements

Momentum

Harp calibration

Emittance

Energy spread

Target Thickness Extrapolation

High Threshold Foils : 2,4,5

Low Threshold Foils : 1,8,12,13,14,15

Goals/plans for beam test opportunity : Monday Feb 9 + Tuesday Feb 10

Test hardware TOF veto at 31MHz and 62MHz (6 hours)

Test FADC without TDC (2 hours)

Test FADC delayed operation (2 hours)

Measure emittance with Run 1 conditions (3 hours)