Tour of the CERN was the never-forgotten exclusive tour inside the experiments chamber. It was something that I would not get everywhere except at CERN.

In this article, I will share about the tour I have joined during my stay at CERN. The Tour of The CERN was arranged by committee exclusively for CERN Summer Student. The tour was divided into several parts depends on the number of CERN facilities that can be visited during that summer. Because of the limited number of seat for each part of the tour, the summer student must reserve their place on the first-come-first-served basis. Eventually, I could visit three out of four CERN’s biggest particle detector: ATLAS, CMS, and LHCb.

Visiting CERN’s Largest Particle Detector : ATLAS

The first tour was to visit ATLAS cavern where the biggest and largest particle detector in the world was built. ATLAS is located near the Globe of Science and Innovation. It is also located near the SR-1 building where I have used to work before. ATLAS (A Toroidal LHC ApparatuS) is one of the seven particle detector experiments (one out of four big particle detector) at CERN.

As the biggest and largest particle detector at CERN, it has 46 metres long and 25 metres in diameter. It weighs approximately 7000 tonnes. The electronics are so advanced and are inter-connected using 3000 km of cable. ATLAS collaboration involves roughly 3,000 physicists from over 175 institutions in 38 countries. Together with CMS, ATLAS involved in the discovery of a particle consistent with the Higgs boson in July 2012.

Visiting CERN’s Heaviest Particle Detector : CMS

The second tour was to visit CMS cavern. CMS (compact muon solenoid) is one of two large general-purpose particle detector at CERN beside ATLAS. CMS is the heaviest particle detector at CERN. CMS is located in its cavern at Cessy, France. In terms of size, CMS is 21.6m long, 15m in diameter, and weighs about 14000 tonnes hence the name “compact”. There are approximately 3800 people from 199 scientific institutes and 43 countries work at CMS.

Visiting CERN’s beautiful detector : LHCb

The third tour was to visit LHCb. Unlike ATLAS and CMS that have their cavern newly built, the LHCb is located in the same cavern as DELPHI which has been decommissioned after the experiment of LEP is stopped. LHCb (Large Hadron Collider beauty) is located in Ferney-Voltaire, France at CERN LHC Point 8. The detector is 4500 tonnes weight and specially designed to record B-Mesons decay. There are approximately 840 people representing 60 scientific institutes from 16 countries build and operate this detector.

The LHCb detector is different compared to other LHC experiments such as ATLAS and CMS. While the others surround the entire collision point with layers of sub-detectors just like an onion, the LHCb detector stretches for 20m along the beam pipe. Its sub-detectors stacked behind each other like books on a shelf. This structure of the detector is based on the behavior of B-Mesons when they are formed from proton collisions.

Visiting CERN’s Antimatter Facility : ALPHA, ASACUSA, ATRAP

So, I went back to CERN Meyrin site to visit its Antiproton Decelerator (AD) facilities. The Antiproton is an “antimatter” of a proton, so some people said that it is an antimatter facility to make it sounds cool. The Antiproton Decelerator facilities house some experiment collaboration. The decelerated antiprotons are ejected to one of the several connected experiments. At that time of my visit, I saw ALPHA, ASACUSA, and ATRAP experiments were being conducted on that facility.

Visiting CERN’s Radioactive Ion Beam Facility : ISOLDE

The next facility that I visited was ISOLDE. ISOLDE (Isotope Separator On-Line Detector) is located at CERN Meyrin site, near the Proton-Synchrotron Booster (PSB). It is operated by the ISOLDE collaboration which consists of CERN and 17 countries across the globe. The facility is dedicated to the production of a large variety of radioactive ion beams. They will be used for many different experiments in the fields of nuclear and atomic physics, solid-state physics, materials science and life sciences.

Visiting CERN’s Cryogenic Test Facility : SM18

The next one to be visited is something cool, literally cool. One of the important components of the LHC is the superconducting magnet. Therefore, CERN has built its own test facility for the superconducting magnet called SM18. The SM18 facility at CERN is a world’s leading magnet test facility for testing magnets and instrumentation. The test facility can provide low temperature (1.9 K up to 80 K) and up to high currents (20 kA). It is located near Prévessin-Moëns, France.

Visiting CERN’s Data Center : Building 513

The last facility that I visited was the CERN Data Center or Computer Center building. As the experiments generate petabytes of data, it is crucial for CERN to have this vast Data Center. Moreover, CERN is an international laboratory which responsible for distributing the experiment data across the globe. Therefore, every scientist and researcher can participate in the research by analyzing the data remotely. The building 513 hosts CERN’s Tier-0 data center. The Tier-0 responsible for storing the raw data, first pass reconstruction, and distribution of raw data to the Tier 1s. It also responsible for reprocessing of data during LHC down-times.

CERN called its data center as Worldwide LHC Computing Grid (WLCG). The WLCG is a global collaboration of computer centers which consists of four layers tiers data center. It was launched in 2002 to provide a resource to store, distribute and analyze the 15 petabytes of data generated every year by the LHC. It now links thousands of computers and storage systems in over 170 centers across 41 countries. The grids serve a community of over 8000 physicists with near real-time access to LHC data. The Grid gives users the power to process, analyze and in some cases to store LHC data.

On the next article, I will talk about the workshop for Summer Student that is exciting! Hope to see you around :).

to be continued…