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2015-03-18T07:49:28Z

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===Scanforth===
* follow the tracks from the primary vertex
* at all stopping points, open a volume
* volume: 3 up, 5 down, 7x7 mm2 (max 7x7 mm2 at the 5th plate down)
*

===About Brick Number===
Example you have to scan brick 36423

in the scanning scripts put 36423
but in Sysal (ChangerStatus.txt file) the brick number MUST be ONLY the 4 last number : 6423

===Create Prediction (for the ScanForth for ex)===
manually create prediction for the scan forth: [[Create Scanforth Prediction]]

or here:
{
#include "scan.C"
EdbScanProc sproc;
sproc.eProcDirClient="/terabig/scan/MICROSCOPE3/ONLINE"; // work directory
EdbPattern pred;
// track stopped at pl24
pred->AddSegment(1,44480.9,16508.4,-0.123,0.04,32); // last BT from the track in linked_tracks.root (-> affine transformation applied!)
EdbAffine2D *aff = new EdbAffine2D(0.998787,-0.003071,0.000637,0.995767,326.291107,-348.701843); // AFF from Pl24
int id[4]={36423,24,1,300};
aff->Invert(); // to "unapply" AFF transformation
pred.Transform(aff); // to "unapply" AFF transformation
pred.Print();
OverwriteErrors(pred,50.,50.,0.,0.6,0.6);
sproc.WritePred(pred,id);
}

===Screen Function===
All the scanning processes should be started in a screen function in order to be able to access from everywhere. In addition, it's very easy to kill an process when it hangs (just kill the screen).

- screen -S myscreen : create a new screen
- screen -r : reattach to the screen
- screen -x : additionally attach to the screen
- inside the screen in order to deattach: Ctrl A D
- inside the screen to close: exit

===Avoid Odyssey Crashes===
Start process with a remote desktop and when it's running, close the remote desktop.

rdesktop -g 1272x930 -k de-ch -u scanner lheppc9

=== Scanning efficiency issues ===

<pre>
Dear Francesco,

this happens when you hit the tracking timeout. In this case, ZERO tracks
are generated.
Try increasing the timeout in SmartTracker8.xxx
Cheers

Cristiano

----- Original Message -----
From: "Francesco Di Capua" <fdicapua@mail.cern.ch>
To: <opera-scanonline@cern.ch>
Sent: Friday, July 18, 2008 10:38 AM
Subject: sysal with high fog

>
> Dear All,
> we received a brick (n.117472) related to the CC event 22877818 with very
> high level of fog,
> we located and reconstructed vertex in intercalibration areas (see
> picture),
> in order to have a reasonable scanning speed the intercalibration areas
> was done with high treshold (900,840) and slope tolerance to 0.4 rad.
> Quality of data is not very good, low efficiency and a lot of views with
> few tracks found (see surface plot).
> Trying to do a better quality volume for vertex analysis, we tried to
> decrease tresholds and increase slope tolerance to 0.6, but we found a
> strange behaviour of Sysal, the scanning seem to start but not microtracks
> at all are found during data taking.
> Do you have any suggestion for parameters to be used in this difficult
> conditions?
>
> Thanks
> Francesco
>
>
</pre>

===Track momentum calculation===

<pre>
Letter from Frederic:
Dear all,

I add a new function in check_vertex_totalscan.C which allows to
estiomate the momentum of a track (using MCS from Magali study). You
just have to call the function PMCS with the trackID as argument.
Exemple below:

void PMCS(int IDTR)
{
//EdbTrackFitter tf; // create track fitter object
EdbMomentumEstimator tf;
tf.SetParPMS_Mag(); //set parameters for detheta=f(theta) (angular
dependance of BT resolution)
tf.eDT0=0.002; //Change a parameter
for(int i=0; i<gAli->Ntracks(); i++ ){
EdbTrackP *t = gAli->GetTrack(i);
float p = tf.PMS_Mag(*t);
float pmin=tf.ePmin; // 90% CL minimum momentum
float pmax=tf.ePmax; // 90% CL maximum momentum
if (IDTR == t->ID())cout << p << " - " << fabs(p-pmin) << " + "
<< fabs(p-pmax) <<endl;
}
}

</pre>
===Track momentum calculation for scanback or scanforth track===

A new script /terabig/scan/macros/testP.C do the momentum calculation of a track using data
from scanback or scanforth. It works in the same way as explain above. (see comments inside
the scripts for details).

===Vertex between 2 BT (or tracks)===
A new script /terabig/scan/macros/vertex_BT.C allows to calculate the vertex position between 2 BT.
It returns the vertex position and the IP (the closest distance between the 2 BT).
In the same script you have another possibilty to estimate the vertex position between a known BT
( that you have to specify) and all the BT from a cp file (that you have to specify).

=== IP between a vertex and a BT (or track)===

The script /terabig/scan/macros/vertex.C allows to check if a BT from a cp file
can be attached to a known vertex that you have to specify.
The output is the IP of the BT w.r.t to the vertex.

=== Change placement of emulsion on stage ===
to do this, you have to change two settings in the opposit way

* in PlateChanger, change in Stage Homing the Stage limiter offset on X and Y
* in Machine default of the Stage, change the XYreference (in opposit way)

Scanning Tips and Tricks - Revision history

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