The CMS electromagnetic calorimeter (ECAL) measures the energy of electrons and photons produced in the LHC collisions with extreme precision. It includes, as main active element, 75848 scintillating crystals made of lead tungstate, a material that…
The CMS detector is going through multiple maintenance works during the LHC Long Shutdown 2 (LS2), the first year of which is approaching its end. The beginning of 2019 saw the CMS Tracker Pixel detector extraction that is now stored in a clean room…
With the connection of the final cable on October 4, CMS completed the installation of new on-detector electronics for the Hadron Calorimeter (HCAL) barrel detector. Following a series of upgrades to the electronics of  various HCAL subdetectors…
On July 25th, 2019, the very first GEM superchambers were installed into the CMS YE- endcap as part of the newest CMS muon subsystem, GE1/1. And while this was a fantastic accomplishment worth celebrating, it was only the beginning of the story.…
As part of the LHC Long Shutdown 2 (LS2) activities at CMS, the CMS Muon Cathode Strip Chamber (CSC) subsystem is having its electronics upgraded in the chambers closest to the beam line. This is done in anticipation of challenges it will face when…
The CMS Gas Electron Multiplier (GEM) subsystem will form an extra layer of detectors, along with the Cathode Strip Chambers (CSC) layers, closest to the beam. The GEM's ability to cope with a very high particle rate will greatly improve muon…
After the LHC was shut down in December 2018 following the successful completion of RUN 2 operation, CMS is undergoing an intensive upgrade and maintenance program during the current two-year break (“Long Shutdown 2” or LS2) in order to ensure an…
During LS2, CMS will install 144 additional muon detector modules specially designed to detect particles produced in the very forward region.    For the CMS experiment, Long Shutdown 2 (LS2) is like very prolonged open heart surgery. The main goal…
In February, the CMS and MoEDAL collaborations at CERN signed an agreement to hand over to MoEDAL a section of the LHC beam pipe that was located inside CMS between 2008 and 2013. The delicate object, 6 metres long and made of beryllium, will now be…
The CMS detector is built from several different layers, surrounding the beam pipe in which the LHC beams collide. The subdetector that is closest to the collisions is the pixel detector. It has a functionality similar to a digital camera taking 40…
After the LHC was shut down at the end of 2018, one might think that physicists working in the large experiments can sit back and relax. On the contrary, CMS will undergo an intensive upgrade and maintenance program during the two-year long break in…
A successful four years of CMS detector operation came to an end last week and now we are beginning a new chapter. The next two-years of Long Shutdown (LS2) will mark an important transition for CMS. Against a background of the intensive 5-yearly…