Ankur Upadhyaya
I am a second-year Ph.D. student in the Astronomy and Astrophysics group at the University of Warwick, UK, where I am actively involved in the extra-galactic and modeling team under the guidance of Dr. Elizabeth StanwayLink opens in a new window. My primary focus is on comparing the spectra of high redshift galaxies (z~5-7), gathered using the Near Infra Red Spectrograph (NIRSpec) instrument of the James Webb Space Telescope (JWST), with those derived from state-of-the-art Binary Population and Spectral Synthesis (BPASS) models. This project involves a comprehensive analysis where I assess the agreement between observations and models, aiming to identify areas for improvement in the existing models. Ultimately, the goal is to enhance our understanding of the early universe by developing models that better predict observations and characterize the physical conditions of Cosmic Dawn.
Before my current role, I completed my Master's thesis at the University of Geneva, Switzerland, where I worked with Prof. Daniel Schaerer and Dr. Rui Marques-Chaves. The focus of my research was the detection of Very Massive Stars (VMS) within Extreme UV-bright star-forming galaxies situated at redshifts (z) between 2 to 4. Utilizing the VMS models developed by Dr. Fabrice Martins and Dr. Ana Palacios from the University of Montpellier, France, I successfully identified the presence of VMS in these galaxies. This work led to additional projects investigating the existence of VMS in the Sunburst Cluster (z=2.37) and in the local universe. I collaborated with Dr. Eros Vanzella's team at INAF Bologna, Italy, to detect VMS in the Sunburst Cluster and collaborated with Dr. Fabrice Martins to extend the study to the local universe, resulting in multiple publications.
For further details on my academic contributions and a complete list of my publications, you can refer to NASA ADS via this linkLink opens in a new window. Additionally, my full CV is available upon request via this linkLink opens in a new window. Feel free to reach out if you have any inquiries or wish to learn more about my research works.
Publications:
First Author:
- Evidence for Very Massive Stars in extremely UV-bright star-forming galaxies at z ~ 2.2 - 3.6Link opens in a new window - Ankur Upadhyaya, Rui Marques-Chaves, et al. 2024, A&A, 686, A185 (2024).
Co-Author:
- Witnessing an extreme, highly efficient galaxy formation mode with resolved Ly and LyC emissionLink opens in a new window - Rui Marques-Chaves, Daniel Schaerer, Eros Vanzella,..., Ankur Upadhyaya et al. 2024, A&A, 691, A87 (2024).
- Inferring the presence of very massive stars in local star-forming regionsLink opens in a new window - Fabrice Martins, Daniel Schaerer, Rui Marques-Chaves, Ankur Upadhyaya 2023, A&A, 678, A159 (2023).
- Clues on the presence and segregation of very massive stars in the Sunburst Lyman-continuum cluster at z = 2.37Link opens in a new window - Uros Mestric, Eros Vanzella, Ankur Upadhyaya et al. 2023, A&A, 673, A50 (2023).
- An extreme blue nugget, UV-bright starburst at z = 3.613 with 90 per cent of Lyman continuum photon escapeLink opens in a new window - Rui Marques-Chaves, Daniel Schaerer,..., Ankur Upadhyaya et al. 2022, MNRAS, 517, 2972.
Conferences, Seminars, Summer Schools:
- Conference Talk: "Evidence for very massive stars in extremely UV-bright star-forming galaxies at z ~ 2.2-3.6" presented at the ESO GALCROSS conference in Brno, Czech Republic from 16-20 September 2024Link opens in a new window.
- Seminar Talk: "Importance of very massive stars at high redshift" presented at the A conversation on the interpretation of stellar populations in the high-redshift Universe science meeting on 29 August 2024 Link opens in a new windowheld at the University of Warwick, UK.
- Seminar Talk: "Wonders of the JWST: the peculiar N-emitters" presented at the extra-galactic and transients weekly seminar at the University of Warwick, UK on 18 Oct 2024.
- Conference Poster: "Evidence for very massive stars in extremely UV-bright star-forming galaxies at z ~ 2.2-3.6" presented at the Extreme Galaxies in their Extreme Environments at Extremely Early Epochs conference in Reykjavík, Iceland from April 29 - May 3, 2024Link opens in a new window.
- Summer School: Attended the "ACES: Advanced Cosmology and Extragalactic Summer SchoolLink opens in a new window" from 2-6 September 2024 at the University of Sussex, UK.
Observing Proposals:
Hubble Space Telescope (HST):
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Co-PI in Cycle 31: Successful allocation of 23 Orbits of HST Observation with WFC3 instrument: High-resolution imaging of the ionizing and non-ionizing radiation of extreme starbursts at z ~ 2.4Link opens in a new window - Rui Marques-Chaves, Daniel Schaerer, John Chisholm, Pascal Oesch,.., Ankur Upadhyaya, Eros Vanzella, Uros Mestric, et al.
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Co-PI in Cycle 30: Successful allocation of 5 Orbits of HST Observation with WFC3 and ACS instruments: Unveiling the origin and nature of the UV-brightest Lyman continuum emitting star-forming galaxyLink opens in a new window - Rui Marques-Chaves, Daniel Schaerer, John Chisholm, Floriane Leclercq, Ankur Upadhyaya.
Very Large Telescope (VLT):
- Co-PI in Cycle P113: Successful allocation of 5 hours of FORS2 Observation: Confirmation of Very Massive Stars and an unusual IMF in a UV bright starburst at z ∼ 2 - Rui Marques-Chaves, Daniel Schaerer, Fabrice Martins, Ankur Upadhyaya.
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Co-PI in Cycle P111: Successful allocation of 16 hours of FORS2 Observation: Observations of the ionizing spectra in the Lyman continuum of distant starbursts - Rui Marques-Chaves, Daniel Schaerer,.., Ankur Upadhyaya.
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Co-PI in Cycle P110: Successful allocation of 18 hours of Xshooter Observation: Xshooter Survey of Extremely UV and Lyα Luminous Star-forming Galaxies at z=2.0-3.6 - Rui Marques-Chaves, Daniel Schaerer,.., Ankur Upadhyaya.
Leadership:
- Representative of all Physics PhD students of the Department of Physics at the Physics Research Committee (PRC)Link opens in a new window of the University of Warwick, UK for the year 2023/24.
- Co-organizer of the UK-wide extra-galactic science meeting titled "A conversation on the interpretation of stellar populations in the high-redshift UniverseLink opens in a new window" held on 29 August 2024 at the University of Warwick, UK.
Honors & Awards:
- Warwick Ph.D. Prize ScholarshipLink opens in a new window for top 3% candidates worth around £200,000 associated with the University of Warwick, United Kingdom. The scholarship covers the Ph.D. tuition fee, and living stipend for 4 years at the UKRI rates, along with other benefits.
- Scholarship worth CHF 12500 for the academic year 2021-22 by the Hans Wilsdorf FoundationLink opens in a new window of Geneva, Switzerland associated with the University of Geneva, Switzerland.
Teaching:
- Senior Graduate Teaching Assistant (GTA) for the 2nd year Undergraduate Electronics Lab PX271 and PX283 for the academic year 2024/25 at the University of Warwick, UK.
- Senior Graduate Teaching Assistant (GTA) for the 1st year Undergraduate Physics Lab PX151 and PX152 for the academic year 2023/24 at the University of Warwick, UK.
- Freelance Tutor of Physics and Mathematics for students following the International Baccalaureate (IB) and other curricula in Geneva, Switzerland during the year 2020-2022.
- Post Graduate Teacher (PGT) of Physics at the central government of India funded Kendriya Vidyalaya (KV) school in the year 2018/2019.
- Freelance Tutor for high and secondary school students in India from 2012 to 2020.
Education:
- PhD Astrophysics - University of Warwick, UK.
- MSc Astrophysics - University of Geneva, Switzerland.
- MSc Physics - National Institute of Technology Agartala, India.
- BSc Physics - Gauhati University, India.
Coming from a poor background, I am deeply passionate about addressing issues related to the upliftment of impoverished people. The challenges of my upbringing have instilled in me a profound belief that poverty is a primary source of human suffering. One of my life goals is to combat human misery, starting with the eradication of poverty. I am convinced that the immediate threat to human civilization is not an external force like an asteroid strike but rather certain negative human impulses that have the potential to bring about our downfall. I believe that unless we collectively suppress these detrimental impulses and nurture positive ones, humanity may face a precarious future. In my view, individual actions of kindness play a crucial role in fostering positive impulses and can be practiced in everyday life. Such actions include extending help, providing motivation, offering encouragement, and simply being kind to others. Unfortunately, poverty poses a significant challenge to amplifying these positive qualities, often bringing out the worst in humanity.
As part of one of the first generations with widespread access to the Internet, I have personally experienced the transformative power of decentralized information. This accessibility has enabled me to climb from the bottom of the societal hierarchy to study science and engage in scientific research at top institutions worldwide. If you are interested in learning more about me or my research work, please feel free to reach out. I am eager to share my experiences and discuss how we can collectively contribute to making a positive impact on the world.