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The Integral Shaped Filament (ISF) is the nearest molecular cloud with rapid star formation, including massive stars, and it is therefore a star-formation laboratory. We use Gaia parallaxes, to show that the distances to young Class II stars (disks) projected along the spine of this filament are related to the gas radial velocity by $$ v = -{Dovertau} + K;qquad tau = 4,{rm Myr}, $$ where $K$ is a constant. This implies that the ISF is a standing wave, which is consistent with the Stutz & Gould (2016) Slingshot prediction. The $tau=4,{rm Myr}$ timescale is consistent with the Slingshot picture that the Orion Nebula Cluster (ONC) is the third cluster to be violently split off from the Orion A cloud (following NGC 1981 and NGC 1987) at few-Myr intervals due to gravito-magnetic oscillations. We also present preliminary evidence that the truncation of the ISF is now taking place $16^prime$ south of the ONC and is mediated by a torsional wave that is propagating south with a characteristic timescale $tau_{rm torsion} = 0.5,{rm Myr}$, i.e. eight times shorter. The relation between these two wave phenomena is not presently understood.
We study the fragmentation of the nearest high line-mass filament, the integral shaped filament (ISF, line-mass $sim$ 400 M$_odot$ pc$^{-1}$) in the Orion A molecular cloud. We have observed a 1.6 pc long section of the ISF with the Atacama Large Mil
(abridged) Within the Orion A molecular cloud, the integral-shaped filament (ISF) is a prominent, degree-long structure of dense gas and dust, with clear signs of recent and on-going high-mass star formation. We used the ArTeMiS bolometer camera at A
Using {it Gaia} Early Data Release 3 (EDR3) parallaxes and Bayesian inference, we infer a parallax of the Westerlund 1 (Wd1) cluster. We find a parallax of $0.34pm{0.05}$ mas corresponding to a distance of $2.8^{+0.7}_{-0.6}$ kpc. The new {it Gaia} E
Recent surveys of the Galactic plane in the dust continuum and CO emission lines reveal that large ($gtrsim 50$~pc) and massive ($gtrsim 10^5$~$M_odot$) filaments, know as giant molecular filaments (GMFs), may be linked to galactic dynamics and trace
We studied the filament structures and dense cores in OMC-2,3 region in Orion A North molecular cloud using the high-resolution N2H+ (1-0) spectral cube observed with the Atacama Large Millimeter/Submillimeter Array (ALMA). The filament network over