Cornell University Unit Name

"Conceptual Design for a Si/W Elecromagnetic calorimeter"

---

The overall design of a future ILC detector is mainly driven by the performance of the electromagnetic calorimeter. An unprecedented resolution on jet energies of 30%/sqrt(E) is required to accomplish sufficient separation of W and Z jets. This can only be achieved with a dense and highly segmented calorimeters. We have chosen a Silicon Tungsten sampling electromagnetic calorimeter of 30 longitudinal layers. The transverse granularity is given by silicon pads of 12 mm^2, readout by a chip for 1k pads directly bump bonded to the detector. The goal of this project is to work out the conceptual design of such a detector. Preserving the tungsten Moliere radius (RM=9.5mm) requires a challenging and aggressive integration of the mechanics, the sensors and the electronics. We aim for 1mm gap between the absorber plates. Within these constraints we need to answer many fundamental questions. How the sensors are fixed, how do we get the signals out, how the heat is transferred, and how the tungsten plates are assembled to form modules and then a barrel or an end cap. This is the main purpose of the project. Three institutes will participate, Annecy le Vieux (LAPP), University of Oregon and SLAC. A realistic design for the barrel, leading to the construction of small prototypes, has to be developed in 2006, followed by an end cap design. By the end of 2007, we should be able to proceed with a technical design. The present support in personnel and funding has to be increased to achieve our goals.

---

Please address the following questions in your statement.

• What are the goals of this R&D project. How does this R&D project address the needs of one or more of the detector concepts?

• If there are multiple institutions participating in this project, please describe the distribution of responsibilities.

• Are there significant recent results?

• What are the plans for the near future(about 1 year)? What are the plans on a time scale of 2 to 3 years?

• Are there critical items that must be addressed before significant results can be obtained from this project?

• Is the support for this project sufficient? Are there significant improvements that could be made with additional support?