Researchers from the Technological Scientific Center of Valparaíso, of the Federico Santa María Technical University, will participate in the largest experiment in the world, monitoring the data collection of its third period of activity.
Three years have passed since the Large Hadron Collider (LHC) entered the maintenance stage: physicists, engineers and technicians from different countries around the world -including Chile- participated in the upgrade that sought to increase the capacity of the accelerator, the number of collisions and its energy to levels never seen before. After this update process, the most powerful collider at a global level began another period of experimentation (Run 3), which will allow testing the standard model of particle physics with greater precision and analyzing larger volumes of data for the exploration of new phenomena.
Located 100 meters underground on the Franco-Swiss border, and with a length of 27 kilometers, this circular underground ring is cataloged, until now, as the largest machine created in the history of mankind. Inside, beams of protons collide at almost the speed of light, with the aim of recreating the conditions existing in the universe shortly after the Big Bang to discover new physics, as happened in 2012 with the experimental demonstration of the Higgs boson.
The role of Chile in the LHC
In the latest update of its technology, our country played a fundamental role through the development of 32 subatomic particle detector modules. This important national commitment was carried out by the Valparaíso Scientific and Technological Center (CCTVal), belonging to the Federico Santa María Technical University (UTFSM), in conjunction with the Pontifical Catholic University of Chile (PUC), and finally, after eight years of work , the detectors were tested and installed during 2021 on the New Small Wheel of the ATLAS muon spectrometer (one of the four LHC experiments and the largest of them).
With the commissioning of the Collider, which began on April 23, what is coming is a testing period of the technologies developed and the improvements implemented, among which are the detectors manufactured in Chile. Additionally, during this process national scientists will have direct participation supervising this new phase of data collection.
Edson Carquín, doctor in physics and researcher at CCTVal and USM, and doctoral student Cristián Allendes, are part of the Chilean researchers who will carry out functions in this new stage of the LHC at CERN, carrying out tasks of monitoring the acquisition systems of data from the ATLAS control room.
“During our stay we will supervise the start-up of ATLAS, which is extensive and detailed: each one of the systems is tested, it is verified that there are no errors at the software level, that all the cables are well connected, we attend to the alerts in case that they turn on due to some technical problem and, in short, we are careful that the detectors and the accelerator work well”, indicates Carquín, who will travel to Switzerland in September. Allendes, for his part, is already at CERN carrying out these tasks.
Along with them, there are several scientists who participate in our country’s collaboration with ATLAS, such as Dr. William Brooks, leader of the cluster of national researchers, and doctors CCTVal Nicolás Viaux and Sebastián Tapia; the latter has also collaborated with other international laboratories such as Brookhaven National Laboratory (BNL), in the United States, and currently heads the research group on jets (jets of particles resulting from collisions) produced in heavy ion shocks and reconstructed at the LHC .
“In the accelerator there are collisions of ions and protons. With the latter, new physics (such as the Higgs) are sought, while in ions we study the Quark-Gluon-Plasma, a unique state of matter that existed shortly after the Big Bang. Part of my job is to be in charge of the software used for data reconstruction, event selection and analysis. I am responsible for the software to work and to carry out the developments, coordination and management that this requires”, comments the researcher.
National Job Projections
Currently, there are two focuses that the Great Collider has: the study of the Higgs boson and the search for new particles, and also the study of nuclear physics. What is relevant is that in both areas Chile has a presence through various institutions, and specifically in the case of the Federico Santa María Technical University and the CCTVal, Dr. Tapia assures that there are great possibilities to continue projecting new works and collaborations.
“For the detector to work and collect data satisfactorily, part of the tasks is monitoring collisions. From now on, it would be ideal for more and more students and researchers to travel to carry out these tasks. Along with this, I think it would be interesting to delve into the technical part, developing and controlling software for the experiment. That would allow us to integrate computer science students working on artificial intelligence, for example. And of course, it would also be important to continue deepening our contribution in the area of physics. The capacities for it exist in our country”, he points out.
At the moment, the LHC continues to test all of its systems and it is expected that the first collisions at an initial energy of 900 GeV (gigaelectronvolts) will begin in the coming days. However, this will increase progressively at the beginning of July until it reaches the design capacity, that is, 13.6 TeV (teraelectron volts), which corresponds to the highest energy that has been achieved to date. With its operations projected until 2025, in the best of cases, the LHC experiments will allow new interactions to be tested and rare phenomena to be observed in order to understand the composition of matter in greater depth, a process that will include the participation of scientists and researchers from the country such as important part of the largest experiment in history.