At the high energy physics department of the “Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas” (CIEMAT) the fundamental objective is the study of the elementary constituents of matter, radiation, and the forces that are responsible for their interactions using energetic collisions at particle accelerators and detectors in underground labs.
The research activities of the CIEMAT are intimately related to the experimental program at the CERN (The European laboratory for Nuclear Research at Geneva in Switzerland), since investigation into progressively smaller distances in this field implies ever increasing higher energy requirements. For this purpose, the largest scientific machine ever made by man, the Large Hadron Collider (LHC), will soon be inaugurated at the CERN. Designed to reach a new energy horizon, this particle accelerator will make protons collide at very high speeds thanks to superconductive electromagnet technology that was developed specifically for this purpose and applied over its large circumference of 27 kilometres. The LHC and its four detectors (CMS, ATLAS, ALICE and LHCb) will be used to study the consequences of the collisions, aiming to detect fundamental particles that are yet to be discovered, like Higg’s boson, a hypothetical particle predicted by theoretical physicists to explain the origins of mass or supersymmetrical particles. These detectors use the interaction between these particles and matter to produce electronically detectable electric or light signals that are collected through millions of channels and stored as data on hard drives, which are subsequently processed in bulk by dedicated computers and sophisticated software developed to reconstruct and simulate the passage of the detected particles through the detector.
The next few months will be crucial for the project, since it is estimated that by April 2008 the first beams will circulate the LHC and June of the same year should see the first of the collisions and data collection. Spanish scientists have participated at all stages of the project, from the design of the experiment, the installation and the adjustments of the equipment, to the preparation for the data processing, and this collaboration is expected to be maintained for the analysis of the produced data. In particular, several groups from the CIEMAT will work at the CMS and ALICE detectors.
The Compact Muon Solenoid (CMS) is a multipurpose cylindrical detector 15 meters in diameter and 21 meters long, weighing over 12500 tons, very complex and with several subsystems devoted to detect the different types of particles. The CIEMAT has collaborated in the construction of the system, specialised in the measurements of muons, as well as the development and implementation of the distributed computing systems GRID that is necessary to gather the data from the detector.
ALICE (A Large Ion Collider Experiment), unlike the previously mentioned detector, is a very specialised experiment, focused on the physics arising from the collisions of the atomic nuclei that will be produced at the collider, and not of the protons themselves. By studying these collisions, the characteristics of matter at extremely high temperatures and densities can be studied. ALICE is also a cylindrical detector but slightly smaller than the CMS. It is 12 meters in diameter, 12 meters long and has a different structure, adapted to the task it is aimed for and will also be fully installed at the CERN before long. The CIEMAT’s contribution to this project includes the GRID infrastructure, scientific calculus and the processing of the data produced by the detector.