Physics highlights at ILC and CLIC

In this lecture, the physics potential for the e+e- linear collider experiments ILC and CLIC is reviewed. The experimental conditions are compared to those at hadron colliders and their intrinsic value for precision experiments, complementary to the hadron colliders, is discussed. The detector concepts for ILC and CLIC are outlined in their most important aspects related to the precision physics. Highlights from the physics program and from the benchmark studies are given. It is shown that linear colliders are a promising tool, complementing the LHC in essential ways to test the Standard Model and to search for new physics.Comment: 15 pages, 9 figures, presented at the 12th International School-Seminar "The Actual Problems of Microworld Physics" in Gomel, Belarus, July 22 - August 2, 201

Measurement of the Higgs decay to electroweak bosons at low and intermediate CLIC energies

In this paper a simulation of measurements of the Higgs boson decay to electroweak bosons in $e^+e^-$ collisions at CLIC is presented. Higgs boson production and subsequent $H\rightarrow ZZ^\ast$ and $H\rightarrow WW^\ast$ decay processes were simulated alongside the relevant background processes at 350 GeV and 1.4 TeV center-of-mass energy. Full detector simulation and event reconstruction were used under realistic beam conditions. The achievable statistical precision of the measured product of the Higgs production cross section and the branching ratio for the analysed decays has been determined.Comment: Talk presented at International Workshop on Future Linear Colliders (LCWS15), Whistler, Canada, 2-6 November 2015, CLICdp-Conf-2016-00

Ultra-Fast Hadronic Calorimetry

Calorimeters for particle physics experiments with integration time of a few ns will substantially improve the capability of the experiment to resolve event pileup and to reject backgrounds. In this paper the time development of hadronic showers induced by 30 and 60 GeV positive pions and 120 GeV protons is studied using Monte Carlo simulation and beam tests with a prototype of a sampling steel-scintillator hadronic calorimeter. In the beam tests, scintillator signals induced by hadronic showers in steel are sampled with a period of 0.2 ns and precisely time-aligned in order to study the average signal waveform at various locations with respect to the beam particle impact. Simulations of the same setup are performed using the MARS15 code. Both simulation and test beam results suggest that energy deposition in steel calorimeters develop over a time shorter than 2 ns providing opportunity for ultra-fast calorimetry. Simulation results for an "ideal" calorimeter consisting exclusively of bulk tungsten or copper are presented to establish the lower limit of the signal integration window.Comment: 10 pages, 16 figures, accepted for publication in NIM

Test beam studies of the light yield, time and coordinate resolutions of scintillator strips with WLS fibers and SiPM readout

Prototype scintilator+WLS strips with SiPM readout for large muon detection systems were tested in the muon beam of the Fermilab Test Beam Facility. Light yield of up to 137 photoelectrons per muon per strip has been observed, as well as time resolution of 330 ps and position resolution along the strip of 5.4 cm.Comment: 7 pages, 11 figures, version accepted for publication in NIM

Time and position resolution of the scintillator strips for a muon system at future colliders

Prototype scintilator + WLS strips with SiPM readout for a muon system at future colliders were tested for light yield, time resolution and position resolution. Depending on the configuration, light yield of up to 36 photoelectrons per muon per SiPM has been observed, as well as time resolution of 0.45 ns and position resolution along the strip of 7.7 cm. (C) 2016 Elsevier B.V. All rights reserved

Potential and challenges of the physics measurements with very forward detectors at linear colliders

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, Spai

Measurement of Th-232(n,5n gamma) cross sections from 29 to 42 MeV

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, Franc