An Open Source Code to Simulate the First Galaxies

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K23437
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0203:Particle-, nuclear-, astro-physics, and related fields
• Research Institution: The University of Tokyo
• Principal Investigator: Hartwig Tilman 東京大学, 大学院理学系研究科(理学部), 助教 (00843434)
• Project Period (FY): 2019-08-30 – 2022-03-31
• Keywords: Public Software / Star Formation / Frst Stars / Milky Way / Semi-analytical Model

Outline of Final Research Achievements

With a team of 11 international scientists, we have developed the semi-analytical model A-SLOTH (Ancient Stars and Local Observables by Tracing Halos). It is the first public code that connects the formation of the first stars and galaxies to observables. We now publish the source code to make it accessible to the public.
On top of dark matter merger trees, A-SLOTH applies analytical recipes for baryonic physics to model the formation of the first generations of stars with unprecedented precision and fidelity. It samples individual stars and includes radiative, chemical, and mechanical feedback. It is calibrated based on six observables. A-SLOTH has versatile applications with moderate computational requirements and can now be used by the scientific community.

Free Research Field

Astrophysics

Academic Significance and Societal Importance of the Research Achievements

A-SLOTH is the first public semi-analytical model that connects the formation of the first stars and galaxies to observables. The code release paper has 11 co-authors from 5 countries, which demonstrates the international support and interest in this project.