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arXiv · 1510.02251

Ongoing star formation in the proto-cluster IRAS 22134+5834

Yuan Wang·Marc Audard·Francesco Fontani·Álvaro Sánchez-Monge·Gemma Busquet·Aina Palau·Henrik Beuther·Jonathan C. Tan·Robert Estalella·Andrea Isella·Frederic Gueth·Izaskun Jiménez-Serra
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Abstract

IRAS 22134+5834 was observed in the centimeter with (E)VLA, 3~mm with CARMA, 2~mm with PdBI, and 1.3~mm with SMA, to study the continuum emission as well as the molecular lines, that trace different physical conditions of the gas to study the influence of massive YSOs on nearby starless cores, and the possible implications in the clustered star formation process. The multi-wavelength centimeter continuum observations revealed two radio sources within the cluster, VLA1 and VLA2. VLA1 is considered to be an optically thin UCHII region with a size of 0.01~pc and sits at the edge of the near-infrared (NIR) cluster. The flux of ionizing photons of the VLA1 corresponds to a B1 ZAMS star. VLA2 is associated with an infrared point source and has a negative spectral index. We resolved six millimeter continuum cores at 2~mm, MM2 is associated with the UCHII region VLA1, and other dense cores are distributed around the UCH{\sc ii} region. Two high-mass starless clumps (HMSC), HMSC-E (east) and HMSC-W (west), are detected around the NIR cluster with N$_2$H$^+$(1--0) and NH$_3$ emission, and show different physical and chemical properties. Two N$_2$D$^+$ cores are detected on an NH$_3$ filament close to the UCHII region, with a projected separation of $\sim$8000~AU at the assumed distance of 2.6~kpc. The kinematic properties of the molecular line emission confirm the expansion of the UCHII region and that the molecular cloud around the near infrared (NIR) cluster is also expanding. Our multi-wavelength study has revealed different generations of star formation in IRAS 22134+5834. The formed intermediate- to massive stars show strong impact on nearby starless clumps. We propose that while the stellar wind from the UCHII region and the NIR cluster drives the large scale bubble, the starless clumps and HMPOs formed at the edge of the cluster.

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Yuan Wang, Marc Audard, Francesco Fontani, Álvaro Sánchez-Monge, Gemma Busquet, Aina Palau, Henrik Beuther, Jonathan C. Tan, Robert Estalella, Andrea Isella, Frederic Gueth, Izaskun Jiménez-Serra. 2015-11-19. Ongoing star formation in the proto-cluster IRAS 22134+5834. https://doi.org/10.1051/0004-6361%2F201526637

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