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The instrumentation of the very forward region of a detector at a future linear collider (ILC, CLIC) is briefly reviewed. The status of the FCAL R and D activity is given with emphasis on physics and technological challenges. The current status of studies on absolute luminosity measurement, luminosity spectrum reconstruction and high-energy electron identification with the forward calorimeters is given. The impact of FCAL measurements on physics studies is illustrated with an example of the sigma(HWW).BR(H - GT mu(+)mu(-)) measurement at 1.4 TeV CLIC. 37th International Conference on High Energy Physics (ICHEP), Jul 02-09, 2014, Valencia, Spain

The measurement of the Higgs production cross-section times the branching ratios for its decays into mu(+)mu(-) and ZZ* pairs at a 1.4 TeV CLIC collider is investigated in this paper. The Standard Model Higgs boson with a mass of 126 GeV is dominantly produced via WW fusion in e(+)e(-) collisions at 1.4 TeV centre-of-mass energy. Analyses of both decay channels are based on a full simulation of the CLIC_ ILD detector. All relevant physics and beam-induced background processes are taken into account. An integrated luminosity of 1.5 ab(-1) and unpolarised beams are assumed. For the H - GT ZZ* decay, the purely hadronic final state (ZZ* - GT q (q) over barq (q) over bar) is considered as well as ZZ* decays into two jets and two leptons (ZZ* - GT qql(+)l(-)). It is shown that the branching ratio for the Higgs decay into a muon pair times the Higgs production cross-section can be measured with 38% statistical uncertainty. It is also shown that the statistical uncertainty of the Higgs branching ratio for decay into a Z boson pair times the Higgs production crosssection can be measured with a precision of 18.3% and 5.6% for the hadronic and semi-leptonic ZZ* decays, respectively. 9th International Physics Conference of the Balkan-Physical-Union (BPU), Aug 24-27, 2015, Istanbul Univ, Beyazit Campus, Istanbul, Turkey

The future compact linear collider (CLIC) offers a possibility for a rich precision physics programme, in particular in the Higgs sector through the energy staging. This is the first paper addressing the measurement of the standard model Higgs boson decay into two muons at 1.4 TeV CLIC. With respect to similar studies at future linear colliders, this paper includes several novel contributions to the statistical uncertainty of the measurement. The latter includes the equivalent photon approximation employed to describe e(+) e(-) and e gamma interactions whenever the virtuality of the mediated photon is smaller than 4 GeV and realistic forward electron tagging based on energy deposition maps in the forward calorimeters, as well as several processes with the Beam-strahlung photons that results in irreducible contribution to the signal. In addition, coincidence of the Bhabha scattering with the signal and background processes is considered, altering the signal selection efficiency. The study is performed using a fully simulated CLIC_ILD detector model. It is shown that the branching ratio for the Higgs decay into a pair of muons BR(H - GT mu(+) mu(-)) times the Higgs production cross-section in WW-fusion sigma(H nu(nu) over bar) can be measured with 38% statistical accuracy at root s = 1.4 TeV, assuming an integrated luminosity of 1.5 ab(-1) with unpolarised beams. If 80 % electron beam polarisation is considered, the statistical uncertainty of the measurement is reduced to 25 %. Systematic uncertainties are negligible in comparison to the statistical uncertainty.

Three methods for handling beam-beam effects in luminosity measurement at ILC are tested and evaluated in this work. The first method represents an optimization of the LEP-type asymmetric selection cuts that reduce the counting biases. The second method uses the experimentally reconstructed shape of the $\sqrt{s'}$ spectrum to determine the Beamstrahlung component of the bias. The last, recently proposed, collision-frame method relies on the reconstruction of the collision-frame velocity to define the selection function in the collision frame both in experiment and in theory. Thus the luminosity expression is insensitive to the difference between the CM frame of the collision and the lab frame. The collision-frame method is independent of the knowledge of the beam parameters, and it allows an accurate reconstruction of the luminosity spectrum above 80 % of the nominal CM energy. However, it gives no precise infromation about luminosity below 80 % of the nominal CM energy. The compatibility of diverse selection cuts for background reduction with the collision-frame method is addressed., Comment: 17 pages, 5 figures, submitted as LC note, Preliminary Note Number = PREL-LC-PHSM-2012-001

The excitation function of the reaction (232) Th(n, 5n gamma)(228) Th from 29 to 42 MeV has been measured for the first time at the quasi-monoenergetic neutron beam of the UCL cyclotron CYCLONE employing the Li-7(p,n) source reaction. Taking advantage of the good energy resolution of the planar High-Purity Germanium (HPGe) detectors, prompt gamma-ray spectroscopy was used to detect the gamma-rays resulting from the decay of excited states of nuclei created by the (n,xn) reactions. The neutron beam was characterized by a combination of time of flight measurements carried out using a liquid scintillation detector and a U-238 fission ionization chamber. Fluence measurements were performed using a proton recoil telescope. The results are compared with TALYS-1.4 code calculations.

This paper summarizes the physics potential of the CLIC high-energy e+e- linear collider. It provides input to the Snowmass 2013 process for the energy-frontier working groups on The Higgs Boson (HE1), Precision Study of Electroweak Interactions (HE2), Fully Understanding the Top Quark (HE3), as well as The Path Beyond the Standard Model -- New Particles, Forces, and Dimensions (HE4). It is accompanied by a paper describing the CLIC accelerator study, submitted to the Frontier Capabilities group of the Snowmass process.

The fragmentation of neutron-rich Sn-132 nuclei produced in the fission of U-238 projectiles at 950 A MeV has been investigated at the FRagment Separator (FRS) at GSI. This work represents the first investigation of fragmentation of medium-mass radioactive projectiles with a large neutron excess. The measured production cross sections of the residual nuclei are relevant for the possible use of a two-stage reaction scheme (fission + fragmentation) for the production of extremely neutron-rich medium-mass nuclei in future rare-ion-beam facilities. Moreover, the new data will provide a better understanding of the memory effect in fragmentation reactions. (C) 2011 Elsevier B.V. All rights reserved.

The production cross sections of neutron-rich fission residues produced in reactions induced by a U-238 beam impinging onto Pb and Be targets were investigated at the Fragment Separator (FRS) at GSI. These data allowed us to discuss the optimum energies in fission for producing the most neutron-rich residues. 4th International Workshop on Nuclear Fission and Fission-Product Spectroscopy, May 13-16, 2009, Cadarache, France

Experiments with radioactive nuclear beams have enabled us to investigate nuclear properties far from stability. Glauber model analysis of total interaction cross sections measurements provides a useful method to determine effective matter radii. In this work we have taken advantage of the relativistic heavy ion facility at GSI for producing and investigate total interaction cross sections of more than hundred medium-mass nuclei along long isotopic chains. International Conference on Nuclear Structure and Dynamics, May 04-08, 2009, Dubrovnik, Croatia

The excitation function of the reaction Th-232(n,5n gamma)Th-228 from 29 to 42 MeV has been measured for the first time at the quasi-monoenergetic neutron beam of the UCL cyclotron CYCLONE employing the Li-7(p,n) source reaction. Taking advantage of the good energy resolution of the planar High Purity Germanium (HPGe) detectors, prompt gamma-ray spectroscopy was used to detect the gamma rays resulting from the decay of excited states of nuclei created by the (n,xn) reactions. The neutron beam was characterized by a combination of time of flight measurements carried out using a liquid scintillation detector and a U-238 fission ionization chamber and fluence measurements carried Out using a proton recoil telescope. The preliminary results are compared with calculations performed using the TALYS-0.72 code. International Conference on Nuclear Data for Science and Technology, Proceedings, Apr 22-27, 2007, Nice, France

Pb-207(n,2n gamma)Pb-206 cross section were measured for incident neutron energies between 6 and 20 MeV with the white neutron beam produced at GELINA. The gamma-ray production cross section for the main transition (803 kcV, 2(+)- GT 0(+)) in Pb-206 is compared to results obtained at Los Alamos and to the TALYS and EMPIRE-II code predictions. 12th International Symposium on Capture Gamma-Ray Spectroscopy and Related Topics, Sep 04-09, 2005, Univ Notre Dame, Notre Dame, IN