Wide Field Surveys of Herbig-Haro Objects

Geysers in the Lagoon : new Herbig - Haro objects in M 8 ⋆

Aims. We search for direct evidence of ongoing star formation by accretion in the Lagoon Nebula (M8), using optical wide-field narrow-band imaging obtained at La Silla Observatory. Methods. We examine [S ] and Hα images for line-emission features that could be interpreted as signatures of outflow activity of the exciting

Herbig Haro Objects in the Orion Nebula 1

Discovery of new embedded Herbig - Haro objects in the ρ Ophiuchi dark cloud ⋆

We report here the discovery of a 30 ′′-chain of embedded Herbig-Haro (HH) objects in the ρ Ophiuchi dark cloud. These HH objects were first detected during a deep KS-band observation (completeness magnitude for point source∼19) made with NTT/SOFI. We confirm their nature with follow-up observations made with H2 v=1–0 S(1) narrow-band filter. We argue that they belong to two different jets eman...

6 A photoionized Herbig - Haro object in the Orion nebula

The spectra of Herbig Haro objects are usually characteristic of ionization and excitation in shock-heated gas, whether an internal shock in an unsteady outflow or a bow shock interface with the interstellar medium. We examine the eastern-most shock – the leading optically visible shock – of a Herbig Haro outflow (HH 529) seen projected on the face of the Orion Nebula, using deep optical echell...

The physics of turbulent and dynamically unstable Herbig–Haro jets

The overall properties of the Herbig–Haro objects such as centerline velocity, transversal profile of velocity, flow of mass, and flow of energy are explained adopting two models for the turbulent jet. The complex shapes of the Herbig–Haro objects, such as the arc in HH34, can be explained by introducing the combination of different kinematic effects such as velocity behavior along the main dir...