Summary :

The ILC Physics Case can be summarized in two main domains: precision measurements and discovery potential. Whereas the principal aim of the precision measurements concerns the Higgs, a secondary but very important aim is to study the top: to determine accurately its mass and to measure its couplings to the SM vector bosons. The top mass will be obtained at 350 GeV, by scanning the threshold of the top pair production. The top couplings to the photon and the Z0 will be measured at about 500 GeV.

For both measurements, a precise mastering of the ElectroWeak loop corrections is essential since it appears that they induce sizeable corrections to the leading mechanisms (typically 5-10%) far larger than the precision achievable at the ILC.

The goals of the TYL project “top-ILC” are twofold: strengthen further the 500 GeV analysis that has been developed in the past years using semi-leptonic events (0), and design means to control theoretically and experimentally the ElectroWeak loop corrections.

In that respect, following the first top-ILC workshop held in KeK (2013) one of the approach that is pursued is to assess the potential of the double leptonic events, where both W’s decay leptonically.

Using Monte Carlo events provided by GRACE(1), it has been shown that experimentally one can cope with the two missing neutrinos and that a Matrix Element(2) analysis of the events using Leading Order expressions(3) should provide top-coupling measurements with an accuracy similar to the one attained using the semi-leptonic events, but with different systematical effects.

French members :
F. Le Diberder, E. Kou, R. Poeschl, F. Richard

Japanese members :
K. Fujii, A. Ishikawa, Y. Kio, Y. Kurihara, T. Suehara, Y. Sumino, T. Tanabe

References :
(0) M.S. Amjad et al. : arXiv:1307.8102 (2013) (1) Progress of Theoretical Physics, Vol. XX, No. X, October 1999 (2) H.J. Behrends et al., CELLO Collab. Z. Phys. C43 (1989) (3) G. Kane, G. Ladinsky and C.P. Yuan, Phys. Rev. D 45 (1992)

website :

Summary :
A compact and highly granular electromagnetic calorimeter at ILC is one of the key requirements for PFA high precision jet reconstruction and realization of ILC physics potential. R&D of silicon-tungsten calorimeter is the goal of this project. We plan to finalize the optimization of the ECAL geometry (dimensions and number of layers), to build and to test a detector (so-called "active sensor unit", or ASU) with 1024 channels per PCB serving 4 silicon sensors with 16x16 pixels, improve the DAQ software and to work on integration of several ASUs into one ILC full-scale detector. In parallel, Tokyo University plans irradiation tests and Kyushu University - tests of different designs of silicon sensors.

French members :
V. Balagura, M. Anduze, V. Boudry, J-C. Brient, R. Cornat, T. Tran

Japanese members :
Y. Kamiya, D. Jeans,

References :
[1] T.H.Tran, "ILD SiW ECAL and sDHCAL dimension-performance optimisation", report at LCWS'13, arXiv:1404.3173 [physics.ins-det]
[2] Ch.Kozakai et al., "Robustness of a SiECAL used in Particle Flow Reconstruction", report at LCWS'13, arXiv:1404.0124 [physics.ins-det]
[3] T.Tomita et al., "A study of silicon sensor for ILD ECAL", report at LCWS'13, arXiv:1403.7953 [physics.ins-det]
[4] Editors: T.Behnke et al., "The International Linear Collider Technical Design Report - Volume 4: Detectors", arXiv:1306.6329 [physics.ins-det]

website :
https://twiki.cern.ch/twiki/bin/view/CALICE/SiWEcal

Summary :
R&D of distributed computing for future large projects like ILC
•Evaluate and gain experience of emerging technologies such as cloud
•More studies on data storage and data transfer
•Both topics will be seen from the long distance point of view

To exchange ideas and knowledge between the two centers
•Re-establish the collaboration beyond the previous Comp_3 project
•Long-term collaboration has a benefit

French members :
P-E. Macchi, L. Caillat-Vallet, B. Delaunay, Y. Hamar, J-Y. Nief, M. Puel

Japanese members :
H. Matsunaga, G. Iwai, K. Murakami, T. Sasaki, S. Suzuki, W. Takase, Y. Watase

References

website