Are all post-starbursts mergers? HST reveals hidden disturbances in the majority of PSBs
| العنوان: | Are all post-starbursts mergers? HST reveals hidden disturbances in the majority of PSBs |
|---|---|
| المؤلفون: | Elizaveta Sazonova, Katherine Alatalo, Timothy M. Heckman, Lauranne Lanz, Kristina Nyland, Ute Lisenfeld, Gregory F. Snyder, K. Decker French, C. M. Urry, Kate Rowlands, Susana E. Deustua, Justin A. Otter, Yuanze Luo, Anne M. Medling, Andreea Petric |
| سنة النشر: | 2021 |
| مصطلحات موضوعية: | Physics, media_common.quotation_subject, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Structural evolution, Asymmetry, Astrophysics - Astrophysics of Galaxies, Galaxy, Residual flux, Space and Planetary Science, Sky, Astrophysics of Galaxies (astro-ph.GA), Hubble space telescope, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Galaxy Astrophysics, media_common |
| الوصف: | How do galaxies transform from blue, star-forming spirals to red, quiescent early-type galaxies? To answer this question, we analyzed a set of 26 gas-rich, shocked post-starburst galaxies with Hubble Space Telescope (HST) imaging in B, I, and H bands, and Sloan Digital Sky Survey (SDSS) i-band imaging of similar depth but lower resolution. We found that post-starbursts in our sample have intermediate morphologies between disk- and bulge-dominated (S\'ersic n$=1.7^{+0.3}_{-0.0}$) and have red bulges, likely due to dust obscuration in the cores. Majority of galaxies in our sample are more morphologically disturbed than regular galaxies (88%, corresponding to >3$\sigma$ significance) when observed with HST, with asymmetry and S\'ersic residual flux fraction being the most successful measures of disturbance. Most disturbances are undetected at the lower resolution of SDSS imaging. Although ~27% galaxies are clear merger remnants, we found that disturbances in another ~30% of the sample are internal, caused by small-scale perturbations or dust substructures rather than tidal features, and require high-resolution imaging to detect. We found a 2.8$\sigma$ evidence that asymmetry features fade on timescales ~200 Myr, and may vanish entirely after ~750 Myr, so we do not rule out a possible merger origin of all post-starbursts given that asymmetric features may have already faded. This work highlights the importance of small-scale disturbances, detected only in high-resolution imaging, in understanding structural evolution of transitioning galaxies. Comment: 31 pages, 19 figures, 2 figure sets, 1 machine-readable table; accepted to ApJ |
| اللغة: | English |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::beb1363f1439744a270ca9d0d36e1253 http://arxiv.org/abs/2105.09956 |
| Rights: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....beb1363f1439744a270ca9d0d36e1253 |
| قاعدة البيانات: | OpenAIRE |
| الوصف غير متاح. |