ALMA-IMF. XXI.: N$_2$H$^+$ kinematics in the G012.80 protocluster: Evidence for filament rotation and evolution
J. Salinas, A. M. Stutz, R. H. ‘Alvarez-Guti’errez, N. A. Sandoval-Garrido, F. Louvet, R. Galv’an-Madrid, F. Motte, M. Armante, T. Csengeri, J. Braine, A. Ginsburg, M. Valeille-Manet, L. Bronfman, P. Sanhueza, D. D’iaz, G. Busquet, A. Koley, M. Bonfand, M. Fern’andez-L’opez, N. Castro-Toledo, R. Veyry, G. Bernal-Mesina
arXiv:2510.03447v1 Announce Type: new
Abstract: (abridged) We aim to characterize kinematic processes in the G012.80 protocluster. We principally focus on the N$_2$H$^+$(1$-$0) emission to trace the dense and cold gas. Additionally, we use lines such as DCN(3$-$2), H41$alpha$, C$^{18}$O(1$-$0), and SiO(5$-$4), as well as continuum maps. We perform a N$_2$H$^+$ hyperfine spectral line fitting to analyze multiple velocity components and spectral parameters. We estimate velocity gradients, column densities, and line-mass profiles for the two main filaments in G012, named R1 and R2. Line-mass profiles follow $lambda$($omega$) = 5660 M$_{odot}$ pc$^{-1}$($omega$/pc)$^{0.30}$ (R1) and $lambda$($omega$) = 6943 M$_{odot}$ pc$^{-1}$($omega$/pc)$^{0.20}$ (R2), which are much larger than those of typical low-mass filaments. R1 and R2 show disparate position-velocity (PV) features. R1 exhibits a transverse velocity gradient of 10.4 kms$^{-1} $pc$^{-1}$ and few dense cores. This gradient is interpreted with a simple rotation toy model, combined with line-mass profile, and corresponds to a rotational timescale of 0.1 Myr. In contrast, R2 exhibits compact velocity structures ($Delta$V arXiv:2510.03447v1 Announce Type: new
Abstract: (abridged) We aim to characterize kinematic processes in the G012.80 protocluster. We principally focus on the N$_2$H$^+$(1$-$0) emission to trace the dense and cold gas. Additionally, we use lines such as DCN(3$-$2), H41$alpha$, C$^{18}$O(1$-$0), and SiO(5$-$4), as well as continuum maps. We perform a N$_2$H$^+$ hyperfine spectral line fitting to analyze multiple velocity components and spectral parameters. We estimate velocity gradients, column densities, and line-mass profiles for the two main filaments in G012, named R1 and R2. Line-mass profiles follow $lambda$($omega$) = 5660 M$_{odot}$ pc$^{-1}$($omega$/pc)$^{0.30}$ (R1) and $lambda$($omega$) = 6943 M$_{odot}$ pc$^{-1}$($omega$/pc)$^{0.20}$ (R2), which are much larger than those of typical low-mass filaments. R1 and R2 show disparate position-velocity (PV) features. R1 exhibits a transverse velocity gradient of 10.4 kms$^{-1} $pc$^{-1}$ and few dense cores. This gradient is interpreted with a simple rotation toy model, combined with line-mass profile, and corresponds to a rotational timescale of 0.1 Myr. In contrast, R2 exhibits compact velocity structures ($Delta$V