who am i?
DESCRIPTION
Who am I?. Daniel John Kirby Carnegie Mellon Physics Class of 2013 In Hall A June-July 2012. Task: Implement systems to make FASTBUS readout faster (using CODA). The Goal: Reducing Deadtime. Main Sources of Deadtime Conversion Readout. Mathematical Model. Tasks to Implement. - PowerPoint PPT PresentationTRANSCRIPT
Who am I?
●Daniel John Kirby●Carnegie Mellon Physics Class of 2013●In Hall A June-July 2012
Task: Implement systems to make FASTBUS readout faster (using
CODA)
The Goal: Reducing Deadtime
Main Sources of Deadtime Conversion
Readout
Mathematical Model
Tasks to Implement
Multiblock Readout
SFI sequencing
Event Blocking and Parallel Buffering
Module Buffering
Sparsification
Library Implementation
Sparsification
Event Blocking Illustrated
Thanks to Dave Abbott for this idea.
Increasing the Buffer Depth
Parallel Buffering
Split TDC buffer into two distinct buffers.Readout and trigger acceptance can happen
concurrently
Sequential vs. Parallel Buffering
Looking Forward: Parallel Module Buffering
Reduces effective trigger rate.Thanks to Igor Rachek for original concept.Thanks to Bryan Moffit for help improving this diagram.
Effect of Module Buffering
Acknowledgements
Once again I'd like to extend special thanks to:
Bogdan Wojtsekhowski Bryan Moffit Dave Abbott Igor Rachek
Magnetic Field in Gas Cherenkov Counter By: Austin Milby, Menchville High School, class 2013
Physics is COOL!
Magnetic Field in Gas Cherenkov Counter Introduction
WHAT: Shielding of PMT’s from magnetic field generated by BigBite
WHY: Magnetic field can cause electrons in PMT to change direction and bend away from dynodes, resulting in skewed data
HOW: By implementing a magnetic shielding box for use in the Cherenkov Counter, we can reduce the presence of the magnetic field around the PMT’s which will result in more accurate data
Study done by SLAC found that Y-orientation of PMT is most severely affected by magnetic field.
Need field to be bellow 1 Gauss!
Detector of the BigBite spectrometer in A1n experiment
I am working with magnetic shielding of the PMT for the Gas Cherenkov counter
BigBite magnet and the field components
Field components are of 5-10 GaussAt PMT the field need to be reducedto the level of 0.5-1 Gauss
Bz component, Gauss
By component, Gauss
Bx component, Gauss
-100cm 100cm
-100cm 100cm
-100cm 100cm
7
2
-2
10
5
1
-1
-2.5
-4
(through center of Cherenkov Counter)
The layout of the PMTs in the counters
Design of Magnetic Shielding Box being considered for use in detector. It will be placed in green area on picture.
Mirror
PMT face
Center of counter where data on previous slide was obtained
BigBite Magnet and the Field Components (2)
(Data taken along purple line)
Bx component, Gauss
By component, Gauss
Bz component, Gauss
(Along surface of PMTs)
100cm -100cm
100cm -100cm
100cm -100cm
Magnetic Shielding
Black box outlines location of PMTs in shielding box.
PMT faces
NOTE: Data taken with external field of 20 Gauss and current in compensation coil set at 120 amps