Taking a closer look at LHC

The TOTEM (Total Cross Section, Elastic Scattering and Diffraction Dissociation) experiment measures the total pp cross-section and study elastic and diffractive scattering at the LHC.  

Modest in size, TOTEM is installed near the point where protons collide in the center of the CMS detector. It uses silicon sensors installed in the LHC tunnel approximately 200 meters away from CMS.

The experiment measures particles scattering at very small angles from the LHC's proton-proton collisions, allowing scientists to study physical processes that can’t be studied by the other LHC experiments, such as how the shape and size of a proton varies with energy.

TOTEM scientists will study inelastic proton-proton collisions in which one proton survives and the other disintegrates and produces "debris" that continues traveling forward. They will also measure elastic collisions in which both protons survive and only slightly deflect each other.

The TOTEM experiment uses three detector types: Roman Pots with microstrip silicon detectors used to detect protons; and Cathode Strip Chambers and GEM Detectors that will measure the jets of forward-going particles that emerge from collisions when the protons break apart.

More information here...


The TOTEM collaboration comprises some 80 physicists from 11 universities and labs in 8 countries.


Xabier Cid Vidal, PhD in experimental Particle Physics for Santiago University (USC). Research Fellow in experimental Particle Physics at CERN from January 2013 to Decembre 2015. He was until 2022 linked to the Department of Particle Physics of the USC as a "Juan de La Cierva", "Ramon y Cajal" fellow (Spanish Postdoctoral Senior Grants), and Associate Professor. Since 2023 is Senior Lecturer in that Department.(ORCID).

Ramon Cid Manzano, until his retirement in 2020 was secondary school Physics Teacher at IES de SAR (Santiago - Spain), and part-time Lecturer (Profesor Asociado) in Faculty of Education at the University of Santiago (Spain). He has a Degree in Physics and a Degree in Chemistry, and he is PhD for Santiago University (USC) (ORCID).



CERN Directory

CERN Experimental Program

Theoretical physics (TH)

CERN Experimental Physics Department

CERN Scientific Committees

CERN Structure

CERN and the Environment



Detector CMS

Detector ATLAS

Detector ALICE

Detector LHCb

Detector TOTEM

Detector LHCf

Detector MoEDAL

Detector FASER

Detector SND@LHC



 For the bibliography used when writing this Section please go to the References Section

© Xabier Cid Vidal & Ramon Cid -  | SANTIAGO (SPAIN) |