Very low mass microcables for the ALICE silicon strip detector

Proposal of abstract for LEB99, Snowmass, Colorado, 20-24 September 1999The ALICE Inner Tracker (ITS) silicon strip layers will use kapton/aluminium microcables (12/14 um thickness) exclusively for all interconnections to and from the front-end chips and hybrids, completely eliminating traditional wirebonding. Benefits are increased robustness and an extra degree of dimensional freedom. Utilising a low-power, low temperature and low-force (10-15 grams) single-point TAB bonding process, aluminium traces are directly bonded through bonding windows in the kapton foil to bond pads on the chips and the hybrid. The same technique is also used to interconnect these microcables to create multi-layer bus structures with "bonded via's". A double-sided strip detector using prototype cables has been installed in the NA57 experiment in 1998

Operation and calibration of the Silicon Drift Detectors of the ALICE experiment during the 2008 cosmic ray data taking period

The calibration and performance of the Silicon Drift Detector of the ALICE experiment during the 2008 cosmic ray run will be presented. In particular the procedures to monitor the running parameters (baselines, noise, drift speed) are detailed. Other relevant parameters (SOP delay, time-zero, charge calibration) were also determined

The ALICE experiment at the CERN LHC

ALICE (A Large Ion Collider Experiment) is a general-purpose, heavy-ion detector at the CERN LHC which focuses on QCD, the strong-interaction sector of the Standard Model. It is designed to address the physics of strongly interacting matter and the quark-gluon plasma at extreme values of energy density and temperature in nucleus-nucleus collisions. Besides running with Pb ions, the physics programme includes collisions with lighter ions, lower energy running and dedicated proton-nucleus runs. ALICE will also take data with proton beams at the top LHC energy to collect reference data for the heavy-ion programme and to address several QCD topics for which ALICE is complementary to the other LHC detectors. The ALICE detector has been built by a collaboration including currently over 1000 physicists and engineers from 105 Institutes in 30 countries. Its overall dimensions are 161626 m3 with a total weight of approximately 10 000 t. The experiment consists of 18 different detector systems each with its own specific technology choice and design constraints, driven both by the physics requirements and the experimental conditions expected at LHC. The most stringent design constraint is to cope with the extreme particle multiplicity anticipated in central Pb-Pb collisions. The different subsystems were optimized to provide high-momentum resolution as well as excellent Particle Identification (PID) over a broad range in momentum, up to the highest multiplicities predicted for LHC. This will allow for comprehensive studies of hadrons, electrons, muons, and photons produced in the collision of heavy nuclei. Most detector systems are scheduled to be installed and ready for data taking by mid-2008 when the LHC is scheduled to start operation, with the exception of parts of the Photon Spectrometer (PHOS), Transition Radiation Detector (TRD) and Electro Magnetic Calorimeter (EMCal). These detectors will be completed for the high-luminosity ion run expected in 2010. This paper describes in detail the detector components as installed for the first data taking in the summer of 2008

Invited Article: Electric solar wind sail: Toward test missions

The electric solar wind sail (E-sail) is a space propulsion concept that uses the natural solar wind dynamic pressure for producing spacecraft thrust. In its baseline form, the E-sail consists of a number of long, thin, conducting, and centrifugally stretched tethers, which are kept in a high positive potential by an onboard electron gun. The concept gains its efficiency from the fact that the effective sail area, i.e., the potential structure of the tethers, can be millions of times larger than the physical area of the thin tethers wires, which offsets the fact that the dynamic pressure of the solar wind is very weak. Indeed, according to the most recent published estimates, an E-sail of 1 N thrust and 100 kg mass could be built in the rather near future, providing a revolutionary level of propulsive performance (specific acceleration) for travel in the solar system. Here we give a review of the ongoing technical development work of the E-sail, covering tether construction, overall mechanical design alternatives, guidance and navigation strategies, and dynamical and orbital simulations

Electric Solar Wind Sail Propulsion System Development

The electric solar wind sail (E-sail) was invented in 2006 and has thereafter been developed rapidly. This paper is a progress report of E-sail technical development as it stands in August 2011. We conclude that E-sail development is well underway, no major problems have been encountered so far and a revolutionary level of performance (1 N in nite Isp thrust from 100-200 kg package) seems realistic

Assembly and validation of the ALICE silicon microstrip detector

The two outermost layers of the ALICE Inner Tracking System consist of 1698 double-sided silicon microstrip modules, which form the Silicon Strip Detector (SSD). The SSD modules offer several novelties, which include the use of TAB-bonding technique for the connection of the front-end electronic via thin aluminium-polyimide cables. The module as well as its parts will be described and the assembling procedure illustrated