Avalanche Photo Diodes for charged particle detection

Introduction

Together with the Universitat de Barcelona we are evaluating the application of Avalanche Photo Diodes (APDs) for the detection of charged particles. APDs are extensively used as devices for the detection of light in particle physics experiment (Silicon PhotoMultipliers^?) and have demonstrated advantages: standard CMOS process allows for cheap and reliable production. Thanks to the advance of micro-electronics highly granular devices can be built. For application in the detection of charged particles in the innermost layers of a collider experiment the challenge is to achieve close to 100% fill factor and to extract the data from the pixel array at high speed.

Publications on the APD design and read-out system are found here:

Proc. Eurosensors XXIV

Nucl.Instrum.Meth. A650 (2011) 120-124

JINST 6 (2011) C01015

Nucl.Instrum.Meth. A650 (2011) 120-124

Proc. LCWS2011

Test Beam

Test beam June 2012. After initial tests in the lab, a small scale prototype has been prepared for a first test in a beam of charged particles at the CERN SPS.

Participants: Eva Vilella (UB), Oscar Alonso, Juan Trenado (UB), Marcel Vos (IFIC), Marça Boronat (IFIC) Dates: 18-24 June, arrival on Thursday 14 to obtain dosimeters and prepare during the weekend Paperwork (CERN): register to CERN as "visitor", but make sure a valid contract is included in the User's Office database. This can be done remotely, through EDH. Paperwork (AIDA): we'll try to fund travel cost through AIDA Arrival to CERN on Thursday 14 to obtain dosimeters and prepare during the weekend. For rules on dosimeters see: http://service-rp-dosimetry.web.cern.ch/service-rp-dosimetry/

To read out such a small prototype with good efficiency we have incorporated a small trigger based on..... Thanks to .... CNM The trigger card and two APD devices are held together in a compact mechanical support structure. The mechanical structure has been designed by Jose Vicente Civera of the mechanics department at IFIC. The three devices are prealigned to 10 micron. Any particle producing a trigger must traverse also the two prototypes. The two devices confirm each other's reading. The "AND" can be formed of hits in both planes to suppress noise hits in long read-out time operation. The second devices can be used to reject events where the particle arrived during the dead time in the prototype read-out (both devices are run off the same clock and read-out is synchronous to the level of a ns).

Test beam October 2012 foreseen for 12-16 October. See the SPS user schedule

Shift instructions

Shifter instructions. For control of the telescope, see the manual below.

In case of any problem with the beam, or the access to the experimental area, you can call the SPS control room (extension 77500). Please, don't call if it isn't strictly necessary. Make sure you have the following information ready; they will typically ask this type of questions. We're in experimental area H6B. We're counting room HNA457. We're door PPE156. We're experiment "DEPFET TB" The responsible person is: Marcel Vos

Useful documents

EUDET status report

EUDET telescope manual manual. This is an old version. The new one is on the MAC in H6.

Software

The conversion program takes raw data from the telescope and converts it into the standard LCIO format for analysis. For the data conversion you need an installation of LCIOC and the eudaq package. This version, provided by Benjamin Schwenker (add a thank you to the paper if you use his code) is independent of Eutelescope. It expects 8 consecutive frames for the DEPFET pxd6+dcdbv2 system. This code must be modified to use for APDs.

tar ball with the source

Photos

setup

setup

setup

setup

setup

TB

-- Main.vos - 25 May 2012