# Gravitational collapse of the OMC-1 region

## TL;DR

This study uses new large-scale N2H+ observations to analyze the gas dynamics of the Orion A cloud's OMC-1 region, revealing evidence of gravitational collapse through accelerated motions towards the Orion Nebula Cluster.

## Contribution

It provides the first detailed kinematic evidence of gravitational collapse in the OMC-1 region using large-scale molecular line observations.

## Key findings

- Detection of blue-shifted profiles indicating inward motions.
- Gas dynamics consistent with gravitational collapse models.
- Explanation of the physical and kinematic structure of OMC-1.

## Abstract

We have investigated the global dynamical state of the Integral Shaped Filament in the Orion A cloud using new N$_2$H$^+$ (1-0) large-scale, IRAM30m observations. Our analysis of its internal gas dynamics reveals the presence of accelerated motions towards the Orion Nebula Cluster, showing a characteristic blue-shifted profile centred at the position of the OMC-1 South region. The properties of these observed gas motions (profile, extension, and magnitude) are consistent with the expected accelerations for the gravitational collapse of the OMC-1 region and explain both the physical and kinematic structure of this cloud.