Physics Without Frontiers Success Story

From Nepal to CERN: Santosh Parajuli's Journey in particle physics
Physics Without Frontiers Success Story
Santosh Parajuli
Sara Anzuinelli

ICTP’s Physics Without Frontiers (PWF) initiative is a global endeavor dedicated to inspiring, educating, and empowering university students in physics and mathematics, particularly in regions where the development of science and technology may still be in its early stages. PWF operates at the intersection of scientific education, diplomacy, and outreach, promoting collaboration among passionate volunteer scientists. PWF has worked with more than 10,000 students worldwide in 50 different countries. This initiative combines hands-on training, lectures, and networking opportunities, acting as catalysts for scientific progress. 

Santosh Parajuli is one of the thousands of students impacted by PWF. His attendance at a 2014 PWF masterclass in Nepal, his home country, inspired him to pursue a career in particle physics. His research interests were further reinforced after he was accepted into the a highly competitive CERN Summer School, a programme that only admits a select group of top-performing students from around the world. Today, he is a postdoctoral research associate at the University of Illinois, Urbana-Champaign, after earning his PhD at Southern Methodist University in Dallas, Texas.

In an interview with ICTP, Santosh talks about his academic journey and the important role that PWF played in getting him to where he is today.

Could you provide us with an introduction to your background and academic journey?

I am a postdoctoral research associate at the University of Illinois, Urbana-Champaign. At present, I am spending some time at CERN in Geneva, where I am working with the ATLAS collaboration. My journey in the field of particle physics has been both thrilling and enriching. It began with my participation in the PWF Master Class on Particle Physics in 2014, during my master’s degree at Kathmandu University, in Nepal. This pivotal experience introduced me to the world of particle physics. Following that, I had the privilege of being selected for a summer studentship at CERN in 2015, where I had the opportunity to immerse myself in the experimental particle physics research . Subsequently, I completed my PhD at the Southern Methodist University in Dallas, Texas. My doctoral thesis focused on the search for Higgs Boson pair production in multiple lepton final states using the ATLAS detector.

How did your family perceive your decision to pursue a career in particle physics?

I hail from Nepal, a region renowned for its rugged and mountainous terrain. My roots lie in this mountainous landscape. My family background is marked by modest beginnings, my parents did not have the privilege to explore the domains of physics and science. Despite all of this, my family has been an unwavering source of support and pride throughout my academic and scientific pursuits. Their support has been a driving force in my journey.

How has your participation in the Physics Without Frontiers program influenced your academic career? 

During my master’s degree in Nepal, particle physics was not a central focus of my curriculum. My pivotal moment arrived in 2014 when I stumbled upon a poster at my university advertising ICTP’s Physics Without Frontiers (PWF) masterclass in particle physics. Intrigued by the opportunity, I applied and was accepted into the program. I was really fascinated by this masterclass and by particle physics. Then, I discovered that I could further pursue my interests at CERN. These formative experiences served as a turning point in my academic journey, propelling me toward my subsequent pursuit of a PhD in particle physics in the United States. 

What inspired you to delve into the field of particle physics?

It was during my studies in classes 11 and 12 that I was introduced to the diverse classifications of fundamental particles. This exposure proved to be a moment of inspiration for me. The realization that these fundamental particles constitute the very building blocks of the universe we inhabit was a compelling revelation. I recognized that comprehending the universe at its most fundamental level necessitated a deep understanding of these elemental particles. This realization served as a powerful motivation to embark on a path in particle physics.

What’s the main focus of your scientific research?

Currently, my research encompasses two projects within the ATLAS experiment.

Firstly, I am actively involved in preparing for the forthcoming High Luminosity Large Hadron Collider (HL-LHC) era. The primary focus is to optimize the computational resources required for charged particle trajectory reconstruction in the new all-silicon Inner Tracker (ITk). To achieve this, we are developing graph neural networks (GNNs) based algorithms for track pattern reconstruction in the ITk that is well-suited for massively parallel computing architectures such as GPUs and FPGAs. 

In addition to this, I am also working on the search for non-resonant production of two Higgs bosons, a process predicted to be exceptionally rare within the confines of the Standard Model. My primary focus centered on final states comprising three electrons or muons. These projects are not only scientifically captivating but also hold the promise of advancing our understanding of fundamental particles and their interactions.

Could you share some insights into the state of physics education and research in Nepal? How do you see the future of scientific research and education evolving in your home country?

Before the advent of the internet era, access to educational resources was primarily concentrated in the capital city of Nepal, Kathmandu. However, with the proliferation of the internet and other technological advancements, the landscape of science education has evolved significantly. Now, access to scientific knowledge has expanded beyond the capital city to reach smaller cities and regions throughout Nepal. This development has led to the establishment of various universities and academic institutions offering programs in physics, chemistry, and other foundational sciences, as well as engineering and the medical field.

While there has been notable progress, it’s important to acknowledge that the pace of development has been gradual. Nonetheless, there are promising signs of growth and transformation. Many individuals, who pursued PhDs and postdoctoral research opportunities in the United States and Europe have chosen to return to Nepal. Upon their return, they have actively contributed to scientific research, education, and technology development within the country. This influx of expertise and knowledge has played a vital role in fostering scientific engagement, enabling research initiatives, and shaping the future of scientific education in Nepal. I am optimistic about the trajectory of scientific research and education in Nepal, and I believe that the combined efforts of individuals who have the capacity to contribute will continue to propel positive change. 

Looking ahead, what are your aspirations and long-term career goals?

I will dedicate the next few years to my current postdoctoral position. Given the opportunity, I aspire to return to Nepal and contribute to higher education in my home country. The specific field or area of focus may vary, but my primary aim is to engage in academia, where I can impart knowledge to new generations of students and inspire them in their academic journeys.

Publishing Date