Sindhu Murthy stands in the HGCAL Module Assembly Center at Carnegie Mellon. She looks at a computer to see data on the upgrade project.

Murthy Develops System to Improve CERN Upgrade Project

By Kirsten Heuring Email Kirsten Heuring

Heidi Opdyke

While helping build modules to upgrade CERN's next-generation Large Hadron Collider, Sindhu Murthy realized there was no easy way to track parts or share information. She designed a database to streamline the project and shared it with researchers across the world.

鈥淥ne thing it greatly reduced was human error,鈥� said Murthy, a Ph.D. student in 91视频鈥檚 Department of Physics. 鈥淚t鈥檚 made the process faster.鈥�

Carnegie Mellon is one of six institutions across the globe serving as Module Assembly Centers (MACs). These centers create parts for CERN鈥檚 high-granularity calorimeter (HGCAL) upgrade, which will be part of the more advanced high luminosity Large Hadron Collider (HL-HDC) scheduled to begin operations in June 2030. Researchers will install the new modules into CERN鈥檚 Compact Muon Solenoid (CMS) detector, increasing the quality and quantity of data collected on subatomic particles. By investigating these particles, physicists hope the research will help explain how the universe works at its most basic level.

Each module is an eight-inch, six-sided device made of several precisely aligned parts. These pieces differ depending on where the module will be installed in the detector. Technicians must select the correct parts then align them within a range smaller than the thickness of a human hair.

Murthy joined the assembly team six years ago when she arrived at Carnegie Mellon. She said she was drawn to the university and the project because she wanted to develop tools that could help make discoveries in high-energy physics.

Murthy studies particles that could reveal new physics beyond the Standard Model.

鈥淲orking on the upgrade would really give me the opportunity to understand what鈥檚 happening with the instrument before I start looking at the data,鈥� Murthy said. 鈥淭hat鈥檚 exactly what made it exciting for me.鈥�

As she built the modules, she noticed CERN did not have a dedicated database for the technicians to record the modules鈥� parts and specifications. She decided to create her own.

鈥淚 told her, 鈥楾ake good notes, and don鈥檛 lose them,鈥欌�� said John Alison, associate professor of physics and Murthy鈥檚 advisor. 鈥淚 assumed she would create a Google Sheet to record the information in an ad hoc way. Sindhu took this as an opportunity to implement something more scalable.鈥�

Sindhu Murthy stands in her office with her arms crossed. She smiles at the camera.
Sindhu Murthy designed a system to make module assembly easier and more consistent for CERN's HGCAL upgrade.

Murthy designed software that tracks every part used in the modules. If a technician scans a piece that does not go with the others, the software alerts the technician so they can replace the part before assembly. The software also guides technicians through the assembly process.

鈥淚t鈥檚 reduced the mental burden on the technicians because they don鈥檛 need to remember what part they鈥檙e using. If they forget the rules or the steps of the assembly, it鈥檚 on the screen for them,鈥� Murthy said.

A database helps ensure every part meets CERN鈥檚 quality standards. The system asks users examine each piece before assembly and check off a list of specifications. If a part does not meet the standards, technicians flag the issue and select a different part, and technicians log assembled modules that fail testing into the database.

鈥淏ecause of the database, we can track the progress and quality of the module assembly that we are doing, and all this feeds into ensuring that only the best modules are going on the detector,鈥� Murthy said.

Murthy first implemented the system at Carnegie Mellon as a test. She found that the system reduced assembly time for the modules and the overall quality improved. After seeing the success, other assembly centers adopted the system as well. All of the teams now host an identical database, and this standardization helps them to track parts, monitor quality and share information between the six centers

For her efforts, Murthy earned a CMS Award, which recognizes individuals who have made significant contributions to the CMS experiment. Alison said that Murthy substantially improved the module assembly process.

鈥淭his database infrastructure will be critical throughout production; we literally couldn鈥檛 operate without it,鈥� Alison said. 鈥淲ithout Sindhu鈥檚 efforts, we鈥檇 be completely lost.鈥�

Murthy plans to continue contributing to the HGCAL upgrade project at Carnegie Mellon and beyond. Once the upgraded detector is operational, she said she is looking forward to making discoveries with it.

鈥淚 am really excited to see what we are able to do with all the extra information once the detector is ready,鈥� Murthy said.