1 Nigel Nation 30 April 2008 More crap Nigel Nation BU ATLAS Group Weekly Meeting 29 April 2008

1

Nigel Nation 30 April 2008

Morecrap

Nigel Nation

BU ATLAS Group Weekly Meeting 29 April 2008

2


Run 33182 (Dec 4 2007) castor/cern.ch/grid/atlas/t0/perm/DAQ/MuonWeekDec07/

169 files (Transfer problem number 50)

TGC sectors 9,10 and 11 were on.

Run Number and Numbers

3


EMS1C Residuals

4


First pass of raw data uses a Hough Transform to remove spurious hits.

2nd pass uses a scalable least squares algorithm allowing up to 12 tubes hit. This allows for an acceptance angle of 80 degrees perpendicular to

chamber surface (1.3π steradians)

No method to remove δ-rays or outliers

Data stored in structured root file for reprocessing Data file can be opened and viewed with self-

written OpenGL event display.

Method

5


Alignment with tracks Currently MOORE does not make tracks between chambers, only

between stations (EM-EI, EM-EO)

Need tracks in adjacent chambers 2D chamber alignment

translations in local chamber coordinates z & y

rotations about x axis

can be done between small and large chambers without TGC information

3D chamber alignment 6 A-line parameter comparison

This needs understanding of TGC 2nd coordinate

Requires alignment of TGCs relative to MDTs

Motivation for Method

6


Run 33182 (Dec 4 2007)

TGC

Hough Animation

7


Run 33182 (Dec 4 2007) TGC sectors 9,10 and 11 were on.

EMS.1C12 is triggered by TGC

No double pulses seen in TDC spectrum (Andrew Eppig)

Use RAW data files and filter leaving only 6-tube 6-row events

Use Hough Transform to locate tracks Only looking at 6 hits

EMS.1C12 Chamber

8


Hough 3D Image

9


EMS1C12 Tracks

621967 1484944114230657

10


Hough Histograms

11


Hough Results

Histogram is being incorrectly filled. As a result the peak is incorrectly found. Currently, top plot (previous slide) bin size is 5 where as bottom is 1.

Second pass of program locates peak from first histogram and expands about its peak. This is why it is failing.

This results in incorrectly found track along with its associated hits

12


Tracks

Hough does not pick out correct track

Bins are set incorrectly

13


Move to Least Squares Routine

Hough Transform is not working and need to generate track residuals.

14


What next?

Modify Hough Transform to get tracks and residuals?

Modify least squares to deal with more that 6 tubes hit?

Intention to be able to look at residuals independently of MOORE. The intention is to compare the two results BOTH the raw hit data and the segments data.

Look at delta-ray production.

15


References

http://homepages.inf.ed.ac.uk/amos/hough.html

Documents

1 Nigel Nation 30 April 2008 More crap Nigel Nation BU ATLAS Group Weekly Meeting 29 April 2008