About Me
I am Navonil from Kolkata, India. I am currently a Final year BS-MS Dual degree student pursuing Physics Major at the Indian Institute of Science Education and Research (IISER), Kolkata, India. My research area is Astrophysics and Cosmology. I am mainly interested in Super Massive Black holes, Cosmology, Large Scale Structure and Gravitational Waves.
Astrophysics Doctoral Researcher
Here are some more details about me and my research interest and ongoing work.
- Institute:Astronomisches Rechen-Institut (ARI), Universität Heidelberg, Germany
- Current City: Heidelberg, Germany
- Degree: PhD in Astrophysics
- Email:navonil.saha@uni-heidelberg.de
navonilastro@gmail.com
My Journey in the field of Astrophysics took off in 2019. During my second year , I got intersted in Astrophysics and wanted to carry forward with it as my main field of study in the future.
The topics on which I got really intersted was Cosmology and Gravitational Waves .
Currently I am working on my Masters thesis on "Matched filter Galaxy group finder", where I am developing an algorithm
for finding group of galaxy clusters and haloes, which are the storehouses of Dark Matter, with the help of technique called Mathched filtering. In future this will be of help for the detection of Dark matter haloes using
Large scale spectroscopic surverys like DESI.
I also interested in working on differnt models of Star formation rate density (SFRD) history in the "Multiverse" which could eventually tell us how the galaxies and ultimately
life forms. I try to adress this by comparison between the SFRDs in these models not only in our universe (or the so called "Standard Cosmolgy") but also in differnt cosmologies as well both using Theoretical and Numerical approaches.
Another topic which I am interested in is Super-Massive Black hole binaries, specifically in the domain of Extreme Mass ratio Inspirals (EMRI's) which is of great importance in the region that will be covred by future Space-based Gravitational Wave detectors like LISA.
I usually try to adress this using N-body Simulations.
Skills
I generally use the follwing Programming Languages and Softwares for my work. However, I am still in the process of learning some of these completely. I also often like to involve myself in small Web Development Projects whenever I get time.
Education
5 Year BS-MS Dual Degree Program
2018 - 2023
Indian Institute of Science Education and Research (IISER), Kolkata, India
All India Senior School Certificate Examination (AISSCE)
2016 - 2018
Aditya Academy Secondary School,Barasat,WB,India, Central Board of Secondary Education (CBSE)
All India Secondary School Examination (AISSE)
2006 - 2016
Aditya Academy Secondary School,Barasat,WB,India, Central Board of Secondary Education (CBSE)
Work Experience
Masters Thesis (MS) Project
Institute for Astronomy , The University of Edinburgh , UK
Supervisors : Prof. John Peacock and Dr. Shadab Alam
MS Thesis Fellow (May 2022 - Present)
MS Thesis fellow at the Institute for Astronomy , The University of Edinburgh , UK under the supervision of Prof. John Peacock , FRS, FRSE and Dr. Shadab Alam . I am working on developing a Matched filter Galaxy group finder . It is now well established that structure in our universe formed by gravitational instability, which magnifies initial density fluctuations and concentrates matter (predominantly dark matter) into nonlinear clumps called dark matter "haloes". Galaxies form within these structures, and a central task for cosmology is to understand how the resulting galaxy populations depend on the properties of the haloes that they inhabit. Next-generation galaxy surveys aim to use the galaxy distribution as a proxy for the overall mass density, in order to study fundamental issues such as the nature of gravity and the properties of the "dark energy" that drives the accelerating cosmic expansion. In this work, it is therefore essential to have a detailed knowledge of the mapping between dark and visible matter. One way of approaching this is to study galaxy groups and clusters, since these systems must correspond to individual dark matter haloes. The state of the art in galaxy groups is the catalogue created from the GAMA spectroscopic survey (https://arxiv.org/abs/1106.1994). The current state of the art group finding algorithms use only spectroscopically observed galaxies, ignoring much larger samples with photometric redshifts. In this project I am focusing on developing a new group finding algorithm based on the technique of matched filtering.Research Projects
National Astronomical Observatory of Japan, Japan
Supervisors : Dr. Maria Dainotti
Research Collaborator (March 2022 - Present)
Research Collaborator at NAOJ under the supervision of Dr. Maria Dainotti.We are working on an Open source and webpage-app for optical lightcurve repository of GRBs. We present a compilation of 527 all WITH MEASURED REDSHIFT LCs of all Gamma Ray Bursts (GRB) detected by the following satellites and ground based Telescopes: Swift UVOT, RATIR, Mitsune, the Subaru Telescope, Tarot, [GROND], from 1993 to 2021. This is the largest repository of GRB optical lightcurves (LCs) published to date. We created a user-friendly interface through a web-based tool to house the repository where the GCN information can be retrieved using the GCN crawler, along with the position, LCs, filter information, and the possibility to visualize the fitting with the Simple Power Law, the Broken Power Law, and the Willingale function. The fitting can be performed with a simple Chi^2 or with Monte Carlo Markov Chain simulations to retrieve the best fit parameters.University of Geneva , Switzerland
Supervisors : Prof. Lucas Lombriser and Dr. Daniele Sorini
Research Intern (March 2021 - December 2021)
Research Intern in the Department of Theoretical Physics, Center for Cosmology and Astroparticle Physics under the supervision of Prof. Lucas Lombriser, SNSF Professor, Department of Theoretical Physics, Center for Cosmology and Astroparticle Physics, University of Geneva. I was mainly working in the field of Theoretical Cosmology. I was part of The Deep Thought Alpha Project and working on Theoretical Cosmology. My main project involves comparing different Star formation models and compare their Star formation rate density (SFRDs) in the multiverse that is comparing these models both in our universe or the Standard Cosmology as well as observing how the models change with respect to each other for different Universes / Cosmology. I was mainly working on two models namely the Bousso and Leichenauer (2008) Model of Star formation : https://arxiv.org/pdf/0810.3044v1 and the Sorini - Peacock (2021) Model of Star formation : https://arxiv.org/abs/2109.01146, along with these I have also studied about the Hernquist-Springel formalism for cosmic star formation . In this project I am also working closely with Dr. Daniele Sorini , Post-Doctoral Fellow working with Prof. John Peacock, FRS, FRSE at the Institute for Astronomy , The University of Edinburgh who are also part of this project. I have recently given a talk on my work titled "Star Formation in the Multiverse" as part of this project, The link of the talk : My TalkScuola Internazionale Superiore di Studi Avanzati (International School for Advanced Studies), Trieste, Italy
Supervisor : Dr. Enrico Barausse
Reading Project (April 2021 - September 2021)
GRAMS-ERC Research Intern in the Department of Astrophysics and Cosmology , International School for Advanced Studies (SISSA), Trieste, Italy, under the supervision of Dr. Enrico Barausse, Associate Professor , Department of Astrophysics and Cosmology, SISSA , Italy. I worked on N-body simulation study of Extreme Mass Ratio Inspirals (EMRIs) and it's relationship with the Post Newtonian evolution of Super Massive Black Hole triplets, and it's possible detection using future space based Gravitational Wave detectors like LISA. I was mainly working on the previous works by Matteo Bonetti , Francesco Haardt, Alberto Sesana and Enrico Barausse : https://arxiv.org/abs/1604.08770v2.National Centre for Radio Astrophysics (NCRA) - TIFR and IUCAA, India
NCRA and IUCAA Faculties
Winter Project Intern (December 2020 - January 2021)
I was selected as a Winter School Intern in 13th Radio Astronomy Winter School (RAWSC), 2020 conducted jointly by National Centre for Radio Astrophysics (NCRA) - Tata Institute of Fundamental Research (TIFR) and Inter University Center for Astronomy and Astrophysics (IUCAA) . The main Project that our group was doing specifically was to analyze different experimental approaches towards detecting Radio sources in our universe using different computational approaches. I also worked on the analysis of Vela radio pulsar data from The Ooty Radio Telescope, and analysis of neutral hydrogen absorption line data and quasar and spectroscopic data from our own Indian Radio Telescope, The Giant Metrewave Radio Telescope (GMRT) and completed experimental projects. Here are the reports of the differt projects : REPORTSInter-University Centre for Astronomy and Astrophysics (IUCAA) , India
IUCAA Faculties
Summer School Intern (May 2020 - June 2020)
Summer School Intern at The Inter-University Centre for Astronomy and Astrophysics (IUCAA) in their Introductory Summer School in Astronomy and Astrophysics (ISSAA) program in the summer of 2020, where I worked mainly on the related and sub disciplinary areas related to Multi Messenger Astronomy. We were trained on the various sub disciplinary field of Astronomy and Astrophysics by the Scientist and expert faculties at IUCAA, some of which included Radiative Processes, Stellar Structure and ISM, Solar Physics, Photometry and Spectroscopy, Active Galaxies, Cosmology, Structure formation in the Universe, Strong Gravitational Lensing, Dark matter and dark energy, Galaxies and Galactic Dynamics, Atomic Clocks , basic to intermediate Radio Astronomy and Gravitational waves including LIGO India.Indian Institute of Technology (IIT), Kharagpur, India
Supervisor : Dr. Bibhudatta Sahoo
Summer Intern (May 2019 - July 2019)
I pursued a Summer Project at Indian Institute of Technology (IIT), Kharagpur in the Department of Electronics and Electrical Communication Engg. under Dr. Bibhudatta Sahoo , Associate Professor, Department of Electronics and Electrical Communication Engg., IIT, Kharagpur in the topic of “Sensor-Signal Conditioning using Cypress Semiconductor Programmable System on Chip (PSoC) 5LP” which mainly dealt with Programmable Gain to Lowpass filtering to again Programmable Gain to Analog-to-Digital Conversion(through ADC) then finally Digital Signal Processing (using VDAC), here I worked with the PSoC 5LP microcontroller to develop a system where I first fed in a Digital Sine wave generated through a sine wave generator and then pass the signal through a low pass filter of a Direct Memory Access(DMA) to a Voltage Digital To Analog Converter (VDAC), the signal was checked using an Oscilloscope and then the analog signal was fed in to the Delta Sigma Analog To Digital (ADC) converter , the output digital values was again checked through a computer hyper terminal such as Putty and the input digital values which is being sent to VDAC is same as the one obtained from the delta sigma ADC. This indicates that our input signal is same as the output signal. In the seond part of the project, I ,generated a sine wave signal and send it through a Programmable Gain Amplifier (PGA) giving a specific gain to the signal ,and then fed the output to a ADC and then the output of the ADC to a VDAC and observed the gained signal through a Oscilloscope, which also came out to be the same with a preferable gain added to it. Here is a detailed report of my project : REPORT.Seminars, Conferences and Workshops attended
32nd meeting of Indian Association for General Relativity and Gravitation (IAGRG 32)
Indian Institute of Science Education and Research Kolkata, India
December 2022 - December 2022
Summer School on Cosmology 2022
International Centre for Theoretical Physics (ICTP), Italy
July 2022 - August 2022
Machine Learning in Solar Physics and Space Weather (SPARC) Workshop 2022
Center of Excellence in Space Sciences India (CESSI), IISER Kolkata, India
June 2022 - July 2022
Summer School on Gravitational Wave Astronomy 2022
International Centre for Theoretical Sciences, India
May 2022 - June 2022
Gravitational Wave Open Data Workshop (ODW) - 2022
LIGO - Virgo - KAGRA Collaboration
May 2022 - May 2022
First IAGRG School on Gravitation and Cosmology
Indian Association for General Relativity and Gravitation (IAGRG)
May 2022 - May 2022
NSM Astrophysics GPU Bootcamp
NVIDIA
May 2022 - May 2022
Physics of the Early Universe (PEU) - 2022 Workshop
International Centre for Theoretical Sciences , India
January 2022 - January 2022
Next Generation Event Horizon Telescope (ngEHT) November 2021 meeting
Event Horizon Telescope (EHT) Collaboration
November 2021 - November 2021
PyAR(Python and Research) SIP Workshop
University of California, Santa Cruz
July 2021 - August 2021
Gravitational Wave Science Communicator's Programme (GWSCP)
LIGO India , IUCAA Pune
January 2021 - February 2021
Introductory Summer School in Astronomy and Astrophysics (ISSAA) 2020
Inter-University Centre for Astronomy and Astrophysics (IUCAA) , India
May 2020 - June 2020
My gallery
I love to do Photography, whenever I find some time I set out with my camera . Being from the City of Joy , Kolkata in India , it is one of the best place for street photogrpahy. Apart from street photogrpahy , I also like to travel a lot and try to capture those moments through my lens. Here ,are some of my shots. For more please visit my Instagram profile @navonil_saha.
Contact
If you have any queries regarding my work or anything related to it, please fell free to contact me via Email or any of my Social media handles.
Location:
Astronomisches Rechen-Institut (ARI), ZAH, Universität Heidelberg, Mönchhofstraße 12-14, 69120 Heidelberg, Germany
Call:
+49 15212549404; +91 9674142937