One-sided Hα excess before the first pericentre passage in galaxy Pairs

Q1 Earth and Planetary Sciences

Monthly Notices of the Royal Astronomical Society: Letters Pub Date : 2024-06-12 DOI:10.1093/mnrasl/slae053

Jiwon Chung, J. Lee, Hyunjin Jeong

{"title":"One-sided Hα excess before the first pericentre passage in galaxy Pairs","authors":"Jiwon Chung, J. Lee, Hyunjin Jeong","doi":"10.1093/mnrasl/slae053","DOIUrl":null,"url":null,"abstract":"\n We present novel insights into the interplay between tidal forces and star formation in interacting galaxies before their first pericentre passage. We investigate seven close pair galaxies devoid of visible tidal disturbances, such as tails, bridges, and shells. Using integral field spectroscopy (IFS) data of extended Calar Alto Legacy Integral Field Area (eCALIFA), we unveil a previously unreported phenomenon: Hα emission, a proxy for recent star formation, exhibits a significant enhancement in regions facing the companion galaxy, reaching up to 1.9 times higher flux compared to opposite directions. Notably, fainter companions within pairs display a more pronounced one-sided Hα excess, exceeding the typical range observed in isolated galaxies with 2σ confidence level. Furthermore, the observed Hα excess in fainter companion galaxies exhibits a heightened prominence at the outer galactic regions. These findings suggest that tidal forces generated before the first pericentre passage exert a stronger influence on fainter galaxies due to their shallower potential wells by their brighter companions. This unveils a more intricate interplay between gravitational interactions and star formation history within interacting galaxies than previously understood, highlighting the need further to explore the early stages of interaction in galaxy evolution.","PeriodicalId":18951,"journal":{"name":"Monthly Notices of the Royal Astronomical Society: Letters","volume":"31 46","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Monthly Notices of the Royal Astronomical Society: Letters","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1093/mnrasl/slae053","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"Earth and Planetary Sciences","Score":null,"Total":0}

引用次数: 0

Abstract

We present novel insights into the interplay between tidal forces and star formation in interacting galaxies before their first pericentre passage. We investigate seven close pair galaxies devoid of visible tidal disturbances, such as tails, bridges, and shells. Using integral field spectroscopy (IFS) data of extended Calar Alto Legacy Integral Field Area (eCALIFA), we unveil a previously unreported phenomenon: Hα emission, a proxy for recent star formation, exhibits a significant enhancement in regions facing the companion galaxy, reaching up to 1.9 times higher flux compared to opposite directions. Notably, fainter companions within pairs display a more pronounced one-sided Hα excess, exceeding the typical range observed in isolated galaxies with 2σ confidence level. Furthermore, the observed Hα excess in fainter companion galaxies exhibits a heightened prominence at the outer galactic regions. These findings suggest that tidal forces generated before the first pericentre passage exert a stronger influence on fainter galaxies due to their shallower potential wells by their brighter companions. This unveils a more intricate interplay between gravitational interactions and star formation history within interacting galaxies than previously understood, highlighting the need further to explore the early stages of interaction in galaxy evolution.

查看原文本刊更多论文

星系对中第一次圆周运动之前的单侧Hα过量

我们对相互作用的星系在第一次圆周运动之前的潮汐力和恒星形成之间的相互作用提出了新的见解。我们研究了七个没有可见潮汐扰动（如尾、桥和壳）的近对星系。利用扩展卡拉奥托遗留积分场区（eCALIFA）的积分场光谱（IFS）数据，我们揭示了一个以前未曾报道过的现象：Hα发射，作为最近恒星形成的替代物，在面向伴星系的区域表现出显著的增强，与相反方向相比，通量最多可高达1.9倍。值得注意的是，伴星系对中较暗的伴星系显示出更明显的单侧Hα过量，超过了在孤立星系中观测到的典型范围，置信度为2σ。此外，在较暗的伴星系中观测到的 Hα 过度在星系外围区域表现得更为突出。这些研究结果表明，由于较暗星系的较亮伴星系的势阱较浅，在第一次圆周运动之前产生的潮汐力对较暗星系的影响更大。这揭示了相互作用星系内部引力相互作用和恒星形成历史之间的相互作用比以前所理解的更加错综复杂，突出了进一步探索星系演化中相互作用早期阶段的必要性。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Monthly Notices of the Royal Astronomical Society: Letters Earth and Planetary Sciences-Space and Planetary Science

CiteScore

8.80

自引率

0.00%

发文量

136

期刊介绍： For papers that merit urgent publication, MNRAS Letters, the online section of Monthly Notices of the Royal Astronomical Society, publishes short, topical and significant research in all fields of astronomy. Letters should be self-contained and describe the results of an original study whose rapid publication might be expected to have a significant influence on the subsequent development of research in the associated subject area. The 5-page limit must be respected. Authors are required to state their reasons for seeking publication in the form of a Letter when submitting their manuscript.