Physics and performance ----------------------- 1) It is claimed that the top quark mass can be measured to a precision of 200MeV from an energy scan, yet the average energy lost to ISR is 25GeV at 500GeV, as well as beamstrahlung effects. How is the accuracy of the top quark measurement consistent with the uncertainty from the latter effects? 2) Comparison to LEP hadronic calorimeters is really very naive: this should rather be done to HERA or LHC-type calorimeters for which resolutions of 30-40%/sqrt(E) are obtained at lower extrapolated cost. What would the gains of the energy-flow approach be in this case? 3) Regarding the overall simulation results, what is gained by having 30 10**6 EM cells rather than 15 or 7 10**6, e.g. by decreasing the sampling frequency which would presumably affect only the EM resolution and/or e.g. by ganging together pads on opposite sides of an absorber layer? 4) The CALICE calorimeter approach is a global one with little or no emphasis on EM calorimetry with respect to overall calorimetry. At this stage, a lot of effort has already gone into the EM calo conceptual design and simulations and there is only one option actively under study. In contrast, the hadronic calorimetry consists of two competing options, one with digital readout of small gas cells, the other with analogue readout of larger-size tiles. Why have the UK groups chosen to join the EM calo effort rather than the perhaps less populated hadronic calo effort? 5) The Panel felt it was essential that the UK should play a leading role in the simulation effort. What is the current status of the simulation effort and what are the UK plans to contribute to this in a visible way over the next months? The TDR simulation had many idealised features: it was not based on a full reconstruction of fully simulated GEANT events, but rather on an idealised reconstruction, only the barrel calorimetry had been simulated and one Expects jets to become more collimated in the end-caps, the two hadronic calorimeter solutions were using totally different tools, the choice of G4 at the present moment for performing these hadronic calorimeter simulations is extremely questionable, etc. Hardware -------- 6) Are there competing technologies to Si-W, for example compensating calorimeters? What is the scope of other LC calorimeter studies throughout the world ? Where would the UK stand if Si-W was not the final chosen option? 7) Is there an issue of radiation damage to the silicon? Will the possibility of running cheaper lower-grade silicon at cyogenic temperatures be considered? 8) What is the status of elementary R&D on one layer of Si/W: connections, FE electronics, mechanics, signal/noise, etc? There was little experience with Si calorimetry in CALICE ~1 year ago: has this changed? 9) Regarding the prototype electronics design: will the on-board FPGAs provide intelligent processing of the data, or are they just passive? Costs and Manpower ------------------ 10) How will the UK provide the strong academic leadership necessary to provide effective coordination of a relatively large number of people spending small fractions of their time on the project? This is a major concern of the Panel. 11) How is the simulation work shared throughout the UK groups ? Who does what ? Who is leading the simulation effort, and how is it being co-ordinated across groups? What is the UK role in simulation within the wider collaboration - do the UK have an established role? Who in the UK will set up the simulation work based on GEANT4? Will GEANT3 and FLUKA also be considered? 12) In more detail, how is the electronics work broken down amongst institutes, including TD. Who does what ? Justify why Extra TD effort is necessary. Who is leading the electronics effort, and how is it being co-ordinated across groups? 13) The travel costs are felt to be high, in particular what are the "beam-time expenses". 14) The Panel was not convinced about the award of RAs (1.6 FTE's), and was confused about how the RA's were to be shared. How would the RAs be distributed across institutes, and why are they essential to the work? A workplan with deliverables would need to be provided. Are there RAs in post already, and are being applied for as assurance that they might be lost in the next RG round? Or are they really new posts?