The involvement of the group in the ATLAS tracking detector consist of several projects :

• Sensor development and installation of the Insertable B-layer (IBL) for run 2
• New tracking detector (front end electronics, mechanics) to be installed for Phase II ( 2025 – 2028 )
• RD53

The ATLAS Inner Detector provides charged particle tracking with high efficiency over the pseudorapidity range of || < 2:5. The Pixel detector, shown in Fig. 1, is the innermost part of the ID. It has approximatively 80 million channels: 67 million in its 3 cylindrical, barrel layers and 13 million in its 3 forward and backward endcap disk layers.

The performance of the innermost layer (B-layer) of the Pixel detector is critical to the full realization of the physics capabilities of the ATLAS experiment. This performance must be maintained to ensure good vertexing and b tagging for the LHC Phase I upgrade physics program, despite increased event pileup and eventual problems in the present B-layer and other Pixel layers.

Exploiting new technology, an additional layer inside the B-layer, the Insertable B-Layer (IBL), maintains robust tracking despite effects arising from luminosity, hardware lifetime, and radiation. The IBL also provides improved precision for vertexing and tagging.

Group members : Abdenour Lounis (staff), Aboud Fallou (engineer), Maurice Cohen-Solal (engineer), Clara Nellist (post doc), Ahmed Bassalat (PhD), Evangelongelos Gkougkousis (PhD), Gisèle Martin-Chassard (staff Omega), Damien Thienpont (staff Omega), Jeanne Tongbong (staff Omega)