Positive feedback, quenching, and sequential super star cluster (SSC) formation in NGC 4945

Author:

Bellocchi E1ORCID,Martín-Pintado J1,Rico-Villas F1ORCID,Martín S23ORCID,Jiménez-Sierra I1

Affiliation:

1. Centro de Astrobiología (CAB), CSIC-INTA , Ctra de Torrejón a Ajalvir, km 4, E-28850 Torrejón de Ardoz, Spain

2. European Southern Observatory , Alonso de Córdova, 3107, Vitacura, Santiago, 763-0355, Chile

3. Joint ALMA Observatory , Alonso de Córdova, 3107, Vitacura, Santiago, 763-0355, Chile

Abstract

ABSTRACT We have used ALMA imaging (resolutions 0.1–0.4 arcsec) of ground and vibrationally excited lines of HCN and HC3N toward the nucleus of NGC 4945 to trace the protostellar phase in super star clusters (proto-SSC). Out of the 14 identified SSCs, we find that eight are in the proto-SSC phase showing vibrational HCN emission with five of them also showing vibrational HC3N emission. We estimate proto-SSC ages of 5–9.7 × 104 yr. The more evolved ones, with only HCN emission, are close to reach the zero-age main sequence (ZAMS; ages ≳105 yr). The excitation of the parental cloud seems to be related to the SSC evolutionary stage, with high (∼65 K) and low (∼25 K) rotational temperatures for the youngest proto and ZAMS SSCs, respectively. Heating by the H ii regions in the SSC ZAMS phase seems to be rather local. The youngest proto-SSCs are located at the edges of the molecular outflow, indicating SSC formation by positive feedback in the shocked regions. The proto-SSCs in NGC 4945 seem to be more evolved than in the starburst galaxy NGC 253. We propose that sequential SSC formation can explain the spatial distribution and different ages of the SSCs in both galaxies.

Funder

European Union

Spanish Ministry of Science and Innovation

AEI

ALMA

NSF

NINS

NRC

MOST

KASI

NAOJ

Publisher

Oxford University Press (OUP)

Subject

Space and Planetary Science,Astronomy and Astrophysics

Cited by 2 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3