Experimental High Energy Physics | ML | Data Science

Arnab Laha

Postdoctoral Researcher · University of the Witwatersrand, Johannesburg, SA  ·  ATLAS Collaboration, CERN

I am currently working as a postdoctoral researcher at the University of the Witwatersrand, Johannesburg, South Africa. I work on the ATLAS experiment at CERN. My current research focuses on Dark Sector searches and the Calorimeter Fast Simulation pipeline for the ATLAS detector.

I obtained my Ph.D. in Experimental High Energy Physics from IISER Pune, India, under the supervision of Prof. Sourabh Dube. My doctoral research focused on searches for physics beyond the Standard Model (BSM) in multilepton final states using at the CMS experiment at CERN. In addition to physics analyses, I contributed to the development and improvement of CMS tracking software in preparation for the High-Luminosity LHC upgrade.

Outside physics, I am an amateur photographer, a keen motorbike rider, and a passionate football fan of Argentina and Barcelona.

Arnab Laha

Arnab Laha · Wits University


01

Research

BSM Search
Search for Beyond Standard Model Signatures

Searches for BSM phenomena in multilepton final states, model-independently and/or targeting specific models: Vector-like leptons, seesaw mechanisms, and leptoquarks. Machine learning to enhance search sensitivity. Currently working on searches exploring Dark Sector models in the ATLAS experiment. Designing a cut-based strategy for emerging jets search using Full Run 3 ATLAS dataset.

CMS Simulation · HL-LHC
Phase 2 Tracking in CMS Fast Simulation

Implementation of the Phase 2 tracker geometry and tracking in the CMS Fast Simulation package for the HL-LHC upgrade, enabling faster Monte Carlo event generation for HL-LHC physics studies.

ATLAS Simulation · HL-LHC
Fast Calorimetry for Long Lived Particles

Working on ATLAS Fast Calorimeter simulation software (AF3) to implement fast reconstruction of long-lived particles in the ATLAS calorimeter.

Machine Learning
Latent Space Representation of HEP Data

Investigating hidden patterns in multidimensional HEP data using PCA, UMAP, and Autoencoders for lepton classification on CERN Open Data. Also uses GANs to speed up W+jets and Z+jets event simulation at LHC.

CMS Service Work
B-Tagging Contact, CMS EXOTICA Group

Reviewing heavy flavor tagging usage in CMS EXOTICA analyses and supporting analyzers with b-tagging tool implementation in liaison with the CMS b-tagging object group. Over 40 analyses reviewed.


02

Publications

Ongoing
Search for first- and second-generation VLLs using full Run 2 + partial Run 3 data at CMS
Review stage in collaboration. I participated in the working phase of this analysis with two main analysts from IISER group.
prep
Constraining Vector-like electron, muon and tau models reinterpreting ATLAS √s = 8 TeV multilepton search
Manuscript in preparation
2022
The CMS Collaboration · Physical Review D

Full publication list on iNSPIRE HEP


03

Teaching & Outreach

Machine Learning and its Physics Application (PH6232)
Teaching Assistant (co-instructor) · Course GitHub
Spring 2023
Lectures on Feynman Diagrams
EHEP Mini-Course, IISER Pune
July 2022
World of Physics: Quantum Mechanics (PHY 202)
Teaching Assistant
Spring 2020
Physics Lab Instructor
INSPIRE Camp, IISER Pune
Jan 2020
Experimental Lab — BSMS 2nd Year (PHY 221)
Teaching Assistant
Fall 2019
Experimental Lab — BSMS 1st Year (PHY 121)
Teaching Assistant
Spring 2019

04

Contact

Office

Room P232
Physics Building
University of the Witwatersrand
Private Bag 3
Wits 2050, Johannesburg, South Africa