User:SWASTIK961/sandbox

• Comment: Add reliable, secondary and independent references to the subject. Fade258 (talk) 02:04, 22 July 2025 (UTC)

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SWASTIK961/sandbox draft

C. Swastik (Swastik Chowbay)
Born	(1994-09-24) September 24, 1994 India
Nationality	Indian
Education	PhD in Astrophysics (Indian Institute of Astrophysics / Pondicherry University, expected 2024)
Alma mater	Indian Institute of Astrophysics, Pondicherry University
Occupation(s)	Research fellow, astronomer, astrophysicist
Scientific career
Fields	Stellar spectroscopy; exoplanet host characterization; galactic chemical evolution; protoplanetary disk imaging
Institutions	Department of Physics, Università degli Studi di Milano
Doctoral advisor	Prof. Ravinder K. Banyal

C. Swastik (born 24 September 1994), also known as Swastik Chowbay, is an Indian astronomer and Type B Research Fellow at the Department of Physics, Università degli Studi di Milano (UNIMI). He received his PhD in astrophysics from the Indian Institute of Astrophysics and Pondicherry University under the supervision of Prof. Ravinder K. Banyal.

Dr. Swastik C in 2024

Career and research

Dr. Chowbay investigates how stellar chemistry, age, and kinematics relate to planet formation and conducts high-contrast imaging of protoplanetary disks.

Major publications

• “Age Distribution of Exoplanet Host‑Stars: Chemical and Kinematic Age Proxies from Gaia DR3” (*Astronomical Journal*, 166, 91, 2023). Showed that stars hosting giant planets are typically younger, α‑poor, and part of the Galactic thin disk, while hosts of small planets are older and kinematically distinct.
• “Galactic Chemical Evolution of Exoplanet Host‑Stars: Are High‑Mass Planetary Systems Young?” (*AJ*, 164, 60, 2022). An analysis of 968 host stars using HARPS‑GTO, CKS, and CPS found that low-mass planets form earlier, while giant planets emerged later in iron-enriched environments.
• “Host‑star Metallicity of Directly Imaged Wide‑orbit Planets” (*AJ*, 161, 114, 2021). Analyzed HARPS, FEROS, and UVES spectra of 22 stars and found that Jupiter-mass planets correlate with host metallicity, whereas super‑Jupiters do not.
• “Carbon Abundance of Stars in the LAMOST–Kepler Field” (*AJ*, 164, 181, 2022).
• “Protoplanetary Disk Imaging” (*A&A*, 680, A114, 2023). Contributed VLT/SPHERE imaging studies (e.g., LkCa 15 and PDS 70) in polarized light.

Ongoing research

Dr. Chowbay is leading efforts in the detection and characterization of exoplanets using advanced facilities: JWST (infrared spectroscopy for atmospheric studies), VLT/ERIS with adaptive optics and coronagraphy for high-contrast direct imaging, and VLT/SPHERE for multi-wavelength planet imaging and disk-science applications

Techniques & instrumentation

Dr. Chowbay has significant experience in high-contrast astronomical imaging. He has served as Co‑PI on multiple VLT/SPHERE observing proposals and conducted approximately 100 hours of host-star spectroscopy at the Himalayan Chandra Telescope (HESP/HFOSC). He is proficient in advanced observational techniques—such as adaptive optics, coronagraphy, and differential imaging—using instruments like VLT/SPHERE to directly image protoplanetary disks and detect exoplanets at close angular separations, including work on systems like HD 141569A, LkCa 15, and PDS 70.

Impact and notability

Dr. Chowbay is known for predicting the phenomenon that “stars hosting giant planets are younger”, an insight that supports the core-accretion model and clarifies how galactic chemical evolution influences planet types.

References

• ArXiv/Banyal et al., *Age analysis of extrasolar planets: Insight from stellar isochrone models*.
• IIA staff profile: Dr. Ravinder K. Banyal (IIA).
• ASI‑2023 abstract: *Are giant planet‑hosting stars young?*

External links

• Google Scholar profile
• ResearchGate profile