What we have now:
Silicon pixels are diodes implanted on semiconductor wafers that offer high spatial resolution in a plane giving the position where the particle has passed to within few microns. Silicon microstrip modules use instead strips as detecting elements. Concerning these, we have thin and thick modules, single and double sided modules . Each module consists of 1 or 2 6'' silicon wafers and is read by many readout chips called APV. Single sided modules measure only one coordinate , double sided modules give instead stereo coordinates. Double sided modules consist of two single sided modules mounted back to back sligtly tilted.
|Layer #||Layer name||Avg. radius||Modules in z||Modules in phi||Total # of modules||Annotations|
|1||PIX barrel||41.05||8||18||128||cylinder divided in half with half modules at the borders|
|4||TIB1||255.||12||26-30||336+336=672||tilted double sided modules|
|8||TOB1||610||12||42||504+504=1008||double sided modules|
|Disc #||Disk name||Avg. z position||Modules in phi||N of rings||Total # of modules||Annotations|
|1||FPIX||34||24||7||In fact the disk is built like a "turbine disk" with 24 "blades"|
|3||TID||24-24-40||3||Rings 1 and 2 double sided|
|4||TID||24-24-40||3||Rings 1 and 2 double sided|
|5||TID||24-24-40||3||Rings 1 and 2 double sided|
|6||TEC||24-24-40-56-40-56-80||7||Rings 1, 2 and 5 double sided|
|7||TEC||24-24-40-56-40-56-80||7||Rings 1,2 and 5 double sided|
|8||TEC||24-24-40-56-40-56-80||7||Rings 1,2 and 5 double sided|
|9||TEC||24-40-56-40-56-80||6||Rings 2 and 5 double sided|
|10||TEC||24-40-56-40-56-80||6||Rings 2 and 5 double sided|
|11||TEC||24-40-56-40-56-80||6||Rings 2 and 5 double sided|
|12||TEC||40-56-40-56-80||5||Ring 5 double sided|
|13||TEC||40-56-40-56-80||5||Ring 5 double sided|
|14||TEC||56-40-56-80||4||Ring 5 double sided|
The TOB system consists of the following main components:
The TIB is made-out of two independent units (Forward and Backward TIB) each one containing four layers of silicon modules arranged in a tilted, cylindrical geometry.Single-(double)-sided detector modules carry one(two) silicon sensor(s) with an active area of about 61.5x116.9mm 2 . In each layer the modules are organized in longitudinal strings of 3 elements on both sides of the supporting structure. The position of the modules in such strings is optimized to assure full coverage from tracks coming from the interaction point. The supporting structure for each layer is made by two half cylinders.
Modules are mounted on a disk organized in petals. We have 8 inner petals and 8 outer petals for each disk. Sensors are mounted on both sides of a petal: so we have 4 positions of the sensors in z:these are named A,B,C,D in order of increasing z.Ring 1,3,5,7 are mounted on sides A and C; the other rings on sides B and D.
Detector Description Database
DDD is the
CMS project that is in charge of the detector database. Waiting for
the final database (in XML) to be ready we have now at least two
descriptions of the tracker:one as tz files for CMSIM and ORCA
and the other for OSCAR. There is also this first approximation of XML description.
The OSCAR description uses Geant4 and can be visualized with Iguana.
Tracker construction database
This is the reference page for tracker construction. There is a database ready to collect all information about the detector pieces. It is a Oracle relational database in Lyon and can be accessed through a Java program. It is necessary to install a stand-alone program on your computer. There is also the Tracker EDMS : a site that collects all mechanical drawings.
Tracker Detector Control System(DCS)
Tracker DCS is already operational on the test beam: it controls classical
"slow control"operating conditions(power supplies voltages, temperatures, humidities,leakage currents) and also Front End electronics configuration data and laser calibration data.
It is based on a Oracle Database plus a control system called SCADA.
The Tracker is self-calibrating and regular electronic calibration should take place in dedicated runs.
Objectives To build a set of graphics objects to help the visualisation of :
3D vs 2D : up to the level of the module, the structure is 3D. So the idea is to use 3D up to this level and then use 2D for further detail. Since single modules are planar in structure, this should not be a problem.
Not a replacement of what we still have but an addition to make what we still have really useful. Now the main problems inside Orca/Iguana are:
Why and when use a Web interface : in some cases you don't need to do complex manipulation (for example rotating a part of the detector in space), instead you just want to visualize some quantity. In this case a simple Web interface would be easier to develop and use. For example : display of data in the Construction Database. prototype
Why a stand-alone program? I some cases, it is absolutely necessary to work inside Orca, although difficult and slow this can be. Instead there is also the possibility that you want to process a lot of events (for example to sum the signal from many events) and you don't want to run Orca one week to get a single picture. In this case the idea is to run Orca in batch for one week, writing events ready to be displayed on disk and then use a fast stand-alone visualisation program to do the visual analysis. This program will get the detector and event description via XML files. DDD already has XML description of the detector; a similar description will be implemented/used to allow program indipendent transmission of events data between ORCA/Oscar and this visualisation stand-alone program. This format will be used for the "ready to be displayed events".
Tentative list of graphical objects to be developed:
Some open problems
java Mostratr npartwhere npart is a number 1-41.