The impact of X-rays on molecular cloud fragmentation and the IMF

Abstract

Star formation is regulated through a variety of feedback processes. In this study, we treat feedback by X-rays and discuss its implications. Our aim is to investigate whether star formation is significantly affected when a star forming cloud resides in the vicinity of a strong X-ray source. We perform an Eulerian grid simulation with embedded Lagrangian sink particles of a collapsing molecular cloud near a massive, 10^7 M_o black hole. The chemical and thermal changes caused by radiation are incorporated into the FLASH code. When there is strong X-ray feedback the star forming cloud fragments into larger clumps whereby fewer but more massive protostellar cores are formed. Competitive accretion has a strong impact on the mass function and a near-flat, non-Salpeter IMF results.

6 pages, 4 figures. Accepted for publication in Astronomy and Astrophysics

References in corpus (12)

• The Two Young Star Disks in the Central Parsec of the Galaxy: Properties, Dynamics and Formation
• Modeling Collapse and Accretion in Turbulent Gas Clouds: Implementation and Comparison of Sink Particles in AMR and SPH
• Star formation through gravitational collapse and competitive accretion
• Diagnostics of irradiated dense gas in galaxy nuclei. II. A grid of XDR and PDR models
• Star Formation Around Super-Massive Black Holes
• A Direct Multigrid Poisson Solver for Oct-Tree Adaptive Meshes
• On the Constancy of the Characteristic Mass of Young Stars
• Instabilities of Spiral Shocks -- II. A quasi-steady State in the multi-phase inhomogeneous ISM
• The Stellar Mass Spectrum in Warm and Dusty Gas: Deviations from Salpeter in the Galactic Centre and in Circum-Nuclear Starburst Regions
• The star formation efficiency and its relation to variations in the initial mass function
• The Chandra View of Galaxy Mergers
• Physical Characteristics of a Dark Cloud in an Early Stage of Star Formation toward NGC 7538: an Outer Galaxy Infrared Dark Cloud?