| Name: | Amrutha S |
| Affiliation: | Indian Institute of Astrophysics |
| Conference ID: | ASI2025_583 |
| Title: | Understanding Stellar Initial Mass Function in the different regions of NGC 628 using MUSE and UVIT observations |
| Authors: | S Amrutha 1,2, Mousumi Das 1 |
| Authors Affiliation: | 1 S Amrutha, Mousumi Das Affiliation ( Indian Institute of Astrophysics, Bangalore - 560034, India)
2 S Amrutha Affiliation (Pondicherry University, Puducherry-605014, India) |
| Mode of Presentation: | Poster |
| Abstract Category: | Galaxies and Cosmology |
| Abstract: | We present a pilot study on the high-mass end of the stellar initial mass function (IMF) in
NGC 628. We focus on variations across the arm, interarm, and spur regions. Our research
emphasizes H$\alpha$ emission primarily detected from O stars, using VLA/MUSE, as well
as UV emissions from both O and B stars obtained with UVIT in star-forming clumps
(SFCs). We estimated the populations of O stars and massive B stars (mass above 10 solar
mass). Subsequently, we found the median stellar IMF index for each region. Our findings
indicate that the IMF index steepens when SFCs are populated with O stars of mass up to 100
solar mass. Notably, the interarm region exhibits a steeper, bottom-heavy IMF than the arms
and spurs across all cases. Furthermore, the ratio of massive to less massive B stars (with
masses ranging from 3 to 10 solar mass) yields a consistent IMF value, even when O stars are
populated differently, making B star mass ratios a more reliable indicator of the IMF. We also
present variations of the IMF with different properties of the SFCs, which gives crucial
results in understanding the IMF. |
