Medical Imaging Group Meeting Minutes : 12th February 2004

 

Attendees : P Nolan, A Boston, M Ibison, H Scraggs,  S Gros,

                   J Norman, A Mather, G Turk, B McGuirk, D Seddon

 

Conference Deadlines : Tomorrow (13/02/04) abstracts needed for both IoP and poster day.  Jenny and Seb who are giving talks at the IoP will also give their Posters from Portland. 

Jenny -  GREAT results

Seb - 

Gerard – Results from Cologne run

Andy – Results from comparison of MCNP and GEANT4

 

Need consistent list of collaborators.

 

Similar presentations will be given at next weeks Daresbury meeting.  Each student needs a 10 minute presentation, focusing on results from Jenny’s data set from the GREAT detector looking in particularly at back detector results as we won’t be doing this in the project due to lack of money.  Andy will also present his results from the comparison of simulations including trends and explanations for any deviations from trends, also giving minima from each program.  They will want to look at PSA.

 

Dave is going to send both Jenny and Andy poster perfect pictures for their upcoming talks.  Helen is going to set up web page for medical imaging along with getting a page set up for Dave to put his images onto.  Need to discuss internal access pages as can actually be seen externally.

 

The Daresbury meeting will be a morning meeting with possible expansion into afternoon for open discussions.  Attendees will be the group from Liverpool (us) along with a group of clinicians from the university, the Daresbury group, Melbourne clinicians and clinicians from Christies hospital, Manchester.  Catherine Dale will also be in attendance.

 

Chris Hall has to be contacted with a list of names from our group and to get a timetable for Wednesday.  Travel has to be arranged as well.

 

Conference to attend has also been brought up.  The group as a whole needs to start scouting for possible conferences.  A couple of workshops have already been found.

Medical meeting in Brighton that Barry would like to attend.

 

Visitors :

Next week sees the arrival of two students from Melbourne.  Need to find work spaces for them.  They will be working alongside students for the next 2 weeks.  These students are coming from the clinician aspect.

The group from Ganil are arriving on Monday to do scan of their detector.  We think the issues of biasing have been resolved.  Barry to test detector.  Space is an issue on the raid.

 

 

 

 

Frame and Feed Through :

Original spacing for the feed throughs is 10 cm.  Cannot unscrew SMA connectors with this tolerance.  Suggest made that a 5mm space is included at regular spaces to minimise number of connectors in close proximity to each other.  There will be 28 connectors in all. Two test inputs on one side and on the other end Bias shutdown and PT500.

Peter Cook to be approached to see if a tool can be made to remove SMA connectors with 15mm and 10mm spacing.

Frame to be desined with slippage in to account for the unknown position of both crystals.  Once scan completed will know precise information. Also if strip close to edge dies need enough slippage to be able to move detectors laterally in frame so get overlap of crystals again (30mm). The gap between detectors will be 200mm, not going to 400mm to start with. Need to find out size of tube required to hold Rat. 

Action : Ask Christie’s next week.

Peter Cook to be approached about manufacturing the frame in house.  This will reduce cost.  Slew ring with gear £1350.

The frame will have to retrofitted to include BGO ball once it gets here.

 

Status of Scan :

Scan has been stable since Monday.  John recompiled kernel as it seems that one of the problems was with dual processor.  Clocks not synced so some jobs were trying to execute before they were supposed to be.  The detector (EXOGAM07) is running without any shutdown and one crystal is not fully biased as it breaks down.  John has also recompiled the online sort so that 1024 files can be written out and the system will not crash after 131 files.  Using the online sort to write to disc worked flawlessly.  There is a new Eurgam disc handler that can read compressed data.  A compressed file is ½ size of uncompressed and take 23% longer to sort.  John can also suppress the output from daq system to write out only risetime and energy parameters further reducing the data size.

 

Grants:

Andy’s EPSRC startup grant has been accepted.  The 125K will go towards a new raid for the sole purpose of detector scans and imaging project.

 

Andy Mather’s talk :

6×6×2 planar simulated in both GEANT (Andy) and MCNP (Gerard).  Output files converted to Java script and analysised using the same packages.  2 – 4 events looked at.

Found that simulations can resolve two interactions in the same segment much better than a real detector can so 2 interactions within 1 mm of each other packaged into one event.  It was noticed that around 900 keV something in the GEANT simulations is giving a kick to the results.  Helen to contact Mike Schumaker at Guelph to see if this has been seen in TIGRESS simulations.

Need to experimentally calibrate what fraction of full energy events are the first interaction.

Lewis palafox – thesis – sim of coaxial detector – where is the minimum?