The Reconstruction of Supersymmetric Theories at High Energy Scales

The reconstruction of fundamental parameters in supersymmetric theories requires the evolution to high scales, where the characteristic regularities in mechanisms of supersymmetry breaking become manifest. We have studied a set of representative examples in this context: minimal supergravity and a left--right symmetric extension; gauge mediated supersymmetry breaking; and superstring effective field theories. Through the evolution of the parameters from the electroweak scale the regularities in different scenarios at the high scales can be unravelled if precision analyses of the supersymmetric particle sector at e+ e- linear colliders are combined with analyses at the LHC.Comment: 36 pages, latex, 6 figure

ROSAT observations of two 'cooling flow' EMSS Galaxies

We present ROSAT observations of two luminous L~10^44 erg/s EMSS galaxies, MS1019+5139 and MS1209+3917, previously classified as 'cooling flow' galaxies. MS1019+5139 does not appear to be spatially extended (<13 kpc) while its spectrum is well fit by a power law with Gamma = 1.73 +0.19-0.18; X-ray variability on a timescale of ~ years is also clearly detected. MS1209+3917 shows no evidence of spatial extension (<50 kpc) but it shows variability, while its spectrum can be fit with thermal bremsstrahlung emission (kT=1.8 +0.9-0.4 keV) or a power law model (Gamma = 2.50 +0.44-0.42, but with excess photoelectric absorption above the Galactic value). All the above argue against thermal emission from a group of galaxies or a galaxy but in favour of an AGN (possibly BL Lac) interpretation. We conclude that no 'normal' galaxies with high X-ray luminosities have yet been detected in the EMSS survey that could be significant contributors to the X-ray background.Comment: 6 pages, LaTeX, 6 postscript figures included, to appear in MNRA

Bottom-Up Reconstruction Scenarios for (un)constrained MSSM Parameters at the LHC

We consider some specific inverse problem or "bottom-up" reconstruction strategies at the LHC for both general and constrained MSSM parameters, starting from a plausibly limited set of sparticle identification and mass measurements, using mainly gluino/squark cascade decays, plus eventually the lightest Higgs boson mass. For the three naturally separated sectors of: gaugino/Higgsino, squark/slepton, and Higgs parameters, we examine different step-by-step algorithms based on rather simple, entirely analytical, inverted relations between masses and basic MSSM parameters. This includes also reasonably good approximations of some of the relevant radiative correction calculations. We distinguish the constraints obtained for a general MSSM from those obtained with universality assumptions in the three different sectors. Our results are compared at different stages with the determination from more standard "top-down" fit of models to data, and finally combined into a global determination of all the relevant parameters. Our approach gives complementary information to more conventional analysis, and is not restricted to the specific LHC measurement specificities. In addition, the bottom-up renormalization group evolution of general MSSM parameters, being an important ingredient in this framework, is illustrated as a new publicly available option of the MSSM spectrum calculation code "SuSpect".Comment: 52 pages, 22 figures. Slight reorganization of sections, a few more results for the neutralino sector, one appendix added on neutralino sector calculation details. Version to appear in Phys. Rev.

Simulation of the CLIC Beam Delivery System Using BDSIM

This note describes the simulation of the CLIC beam delivery system (BDS) using a Geant4 [1] based program BDSIM. BDSIM is designed flexibly in order to track particles through the BDS of a generic linear collider and includes particle interactions and production of secondaries in materials. The code itself is described in Section 2 and this note serves as initial documentation for the programme. The detailed input to the program is controlled by an optics file and cards file, described in Section 10 and Section 11 respectively and the processes present are outlined in Section 4. Results are presented for the tracking performance of the program (Section 3) and its use in determining the backgrounds from halo particles (Section 5); particular emphasis is placed on the determination of muon production rates (Section 6) due to halo loss upstream of the interaction point (IP). Some earlier studies of energy deposition in spoilers are also included for completeness in Section 7. The simulation of a laserwire system is introduced in Section 8

Beam Delivery System in ILC

The challenges of the International Linear Collider (ILC) Beam Delivery System (BDS) are reviewed and compared with the achievements in SLC and FFTB. An overview is provided of the necessary R&D for the BDS design, beam simulations and benchmarking in test facilities, especially the ATF2 facility under construction at KEK. The major issues are explored both from the beam dynamics and the technological point of view, as well as the plans foreseen and the schedule to address them

Prospects for Top Flavour Violation at a Future Linear Collider

The possibility of flavour violaion via a coupling Ztc at centre of mass energies of 300GeV is discussed. Possible limits on a right-handed coupling are obtained and the prospects compared to those at the LHC

Test Beams for ILC Final Focus

The International Linear Collider (ILC) will require 250 GeV-500 GeV electron and positron beams to be focused down to a few nanometers in the vertical dimension at the interaction point. This will require unprecedented specifications for the final focus region and related controls. To this end, a set of international test facilities are being planned to address key performance goals of beam delivery sub-systems. These test facilities are described and future plans outlined

Detector Simulation

The interim status of the 1998/9 ECFA/DESY simulation programme is described. The fast simulation program, SIMDET, and the full GEANT simulation, BRAHMS, are shown to be working and being used in physics and detector studies for a future linear collider. An alternative fast simulation program, SGV, is also available. A selection of physics and detector study results are shown and an overview given of which tools to use for which purpose

Summary of Laser-wire Mini Workshop

A summary is presented of the laser-wire mini workshop held as part of Nanobeam 2005. Topics that were covered include machine optics studies of the ILC diagnostics section, simulation of laser-wires in the ILC beam delivery system, the development of pulsed laser stacking plus applications, a laser interferometer in an optical cavity, fast laser-wire scanning with electro-optics, and status reports on the ATF and PETRA laser-wire systems