About Me

I specialize in the study of Galaxy Formation and Evolution. My primary focus is on understanding how galaxies changes their properties along the large scale structures (LSSs). I am deeply interested in understanding star formation activities and am keen on exploring properties such as morphology, chemical abundance, kinematics, and dynamics across various cosmic web density regimes. My work aim to provide crucial insights into galaxy formation and evolution. Most of my research has been based on datasets from Subaru's HSC-SSP. Additionally, I've recently incorporated JWST data to further delve into the morphology of galaxies.

Past and current research works

A central question in galaxy evolution is how star formation in galaxies correlates with various physical parameters and how these relationships might have changed over time. Delving into this central question, my past and current research endeavors aim to shed light on the intricate interplay between star formation and the evolving cosmic environment.
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1. Mapping the Large Scale Structure and Environmental Dependence of SF Galaxies (Laishram et al; under review)

Employed narrow-band imaging to understand galaxy evolution within the cosmic web. Introduced a technique using Hyper Supreme-Cam on the Subaru Telescope, enhancing redshift estimation precision. Investigated environmental impacts on galaxy properties in the LSS.

2. Hα and Continuum Size of Star Forming Galaxies around CAMIRA Cluster at z∼0.4 (paper in prep)

Explored the environmental effects on galaxy morphology and star formation around CAMIRA clusters. Analyzed star formation in emission line galaxies, revealing centralized star formation in cluster core galaxies possibly due to ram-pressure stripping.

3. Exploring Triple Narrow Band with HSC-SSP (in prep)

Used triple narrow-band filters to map Hα+[OII] “dual emitters” and study their relationship. Developed an empirical relationship for dust extinction using the [OII]/Hα ratio, highlighting environmental influences on galaxy dust content.

4. Filamentary Overdensities at z∼1.5: Star Forming Activities and Morphology Analysis (paper in prep)

Examined a filamentary overdensity of [OII]-selected galaxies in the COSMOS field using the Subaru HSC and JWST. Investigated the correlation between star formation activities and environment, uncovering higher star-forming activities and merger rates in overdense regions.

5. Ongoing Project: Nebular Properties of Star-Forming Galaxies

Studying nebular emission lines and the chemical abundance in galaxies' interstellar medium, especially at z∼1.5. Comparing the state of the ISM to both local and higher redshift galaxies using key nebular emission lines, in preparation for upcoming surveys like Subaru/PFS and VLA/MOONS.

Education

PhD Astronomy

October 2021 -- Present • Astronomical Institute, Tohoku University, Sendai, Japan

MSc Astronomy

October 2019 -- September 2021 • Astronomical Institute, Tohoku University, Sendai, Japan

Bachelor of Engineering in Computer Science & Engineering

2014 -- 2018 • JSS Science and Technology University, India

Academic Visiting

CIERA, Northwestern University, Chicago

October 2023 - Present • Working with Prof Allison Strom

IPAC/Caltech, Pasadena, California

August 2023 - September 2023 • Working with Dr Takahiro Morishita

NAOJ, Subaru Telescope Hilo Base Facility, USA

November 2022 – December 2022 • Working with Prof Yusei Koyama

Complete CV

For a comprehensive view of my academic and professional journey, you can download my complete CV below.

Download Complete CV

Ronaldo Laishram

I'm a PhD student working in Galaxy Formation and Evolution
at Tohoku University, Japan.