The evolution of the jet from Herbig Ae star HD 163296 from 1999 to 2011

Abstract

Young A and B stars, the so-called Herbig Ae/Be stars (HAeBe), are surrounded by an active accretion disk and drive outflows. We study the jet HH 409, which is launched from the HAeBe star HD 163296, using new and archival observations from Chandra and HST/STIS. In X-rays we can show that the central source is not significantly extended. The approaching jet, but not the counter-jet, is detected in Ly alpha. In addition, there is red-shifted Ly alpha emission extended in the same direction as the jet, that is also absent in the counter-jet. We can rule out an accretion or disk-wind origin for this feature. In the optical we find the knots B and B2 in the counter-jet. Knot B has been observed previously, so we can derive its proper motion of 0.37+-0.01 arcsec/yr. Its electron density is 3000/cm^3, thus the cooling time scale is a few months only, so the knot needs to be reheated continuously. The shock speed derived from models of H alpha and forbidden emission lines (FELs) decreased from 50 km/s in 1999 to 30 km/s in 2011 because the shock front loses energy as it travels along the jet. Knot B2 is observed at a similar position in 2011 as knot B was in 1999, but shows a lower ionization fraction and higher mass loss rate, proving variations in the jet launching conditions.

14 pages, 8 figures, accepted by A&A

References in corpus (14)

• Accretion Rates in Herbig Ae stars
• Parameters of Herbig Ae/Be and Vega-type stars
• A search for strong, ordered magnetic fields in Herbig Ae/Be stars
• Recipes for stellar jets: results of combined optical/infrared diagnostics
• Discovery of a bipolar X-ray jet from the T Tauri star DG Tau
• T Tauri Jet Physics Resolved Near The Launching Region with the Hubble Space Telescope
• A Disk-Wind Model for the Near-Infrared Excess Emission in Protostars
• The HD 163296 Circumstellar Disk in Scattered Light: Evidence of Time-Variable Self-Shadowing
• A study of the magnetic field in the photospheric and circumstellar components of Herbig Ae stars
• Jets, accretion, coronae and all that: The enigmatic X-rays from the Herbig star HD 163296
• The nature of the soft X-ray source in DG Tau
• The discovery of an expanding X-ray source in the HH 154 protostellar jet
• Revealing the fastest component of the DG Tau outflow through X-rays
• The evolution of the X-ray emission of HH 2 - Investigating heating and cooling processes

Cited by in corpus (10)

• A Spatially Resolved Vertical Temperature Gradient in the HD 163296 Disk
• Relating jet structure to photometric variability: the Herbig Ae star HD 163296
• ALMA detection of the rotating molecular disk wind from the young star HD 163296
• Disk Dispersal: Theoretical Understanding and Observational Constraints
• Disk Illumination and Jet Variability of the Herbig Ae Star HD 163296 Using Multi-Epoch HST/STIS Optical, Near-IR, and Radio Imagery and Spectroscopy
• A localized kinematic structure detected in atomic carbon emission spatially coincident with a proposed protoplanet in the HD 163296 disk
• The UV Perspective of Low-Mass Star Formation
• Recollimation boundary layers as X-ray sources in young stellar jets
• A MUSE view of the asymmetric jet from HD 163296
• Pre main sequence: Accretion & Outflows