# Analysis of the 4-Cell Problem in the LHCb's Electromagnetic Calorimeter

- Institution: CERN
- Department: Summer Student Lecture Programme General
- Speaker: Jinkyu So
- Year: 2025
- Language: English
- Subjects: Mathematics, Biology
- Source: [CERN](https://videos.cern.ch/record/3023152)
- Licence: [CERN](http://copyright.web.cern.ch)
- Who can watch: Tweens profiles and older (sources give no ratings; placed by Invisible Network from the source's own words)

Jinkyu is an undergraduate physics student at Hanyang University in Seoul, South Korea. He has been working as a research intern with the KCMS Elementary Particle Physics group at his university.

This summer, he has been involved in Data Quality and Monitoring for the LBD group in LHCb, focusing on a project analyzing the 4-Cell Problem in the LHCb electromagnetic calorimeter. This issue, which has been recurring throughout the past year, often goes unnoticed, leaving potentially affected data included in the ntuples used for research. His work has centered on identifying the impact of this problem, understanding its behavior, and assessing whether the data can still be used for specific types of analyses. In this presentation, he will share the details of his investigation, as well as his contributions and insights for future occurrences..

0:00:00 Slide 1

0:01:42 Slide 2

0:03:01 Slide 3

0:04:48 Slide 4

0:06:14 Slide 5

0:07:57 Slide 6

0:09:39 Slide 7

0:10:46 Slide 8

0:11:51 Slide 9

## Lectures

1. [Analysis of the 4-Cell Problem in the LHCb's Electromagnetic Calorimeter](https://invisiblenetwork.ai/learn/cern/3023152/82c428c78103), 14 min (CERN's player)