1997•Publications of the Astronomical Society of the PacificOpen access

Herbig-Haro Objects in the \rho Ophiuchi Cloud

Bruce A. Wilking, Richard D. Schwartz, Tina Marie Fanetti, E. D. Friel

Open full text 26 citations

Abstract

Using deep, narrow-band images of the main ρ Oph dark cloud centered on the wavelengths of Hα and [S~II], we present evidence for three new Herbig-Haro objects. This increases the total number in the cloud to five. In addition, positions for 5 candidate Herbig-Haro objects are given. Relatively high [S~II]/Hα ratios indicate low excitation conditions for all of these nebulae. We list potential exciting stars for each Herbig-Haro object and candidate by identifying nearby young stellar objects with strong infrared excesses and/or millimeter continuum emission. The location of most of these nebulae near the cloud edges underscores the important role that extinction by dust plays in the ρ Oph cloud in masking the presence of Herbig-Haro objects. Among the newly identified Herbig-Haro objects is a jet-like string of emission nebulae emanating from the classical T Tauri star SR~4. [S~II] emission is also found coincident with a knot of strong molecular hydrogen emission associated with the highly-collimated VLA~1623 molecular outflow. Indeed, the low excitation nature of all of the objects in our study, coupled with the high extinction of the cloud, suggests that a deep survey for shocked molecular hydrogen at λ=2.122 μm would be the best way to search for evidence of strong winds from the large population of young stellar objects in the cloud.

Open-access reader

About this research paper

What this paper is about

Using deep, narrow-band images of the main ρ Oph dark cloud centered on the wavelengths of Hα and [S~II], we present evidence for three new Herbig-Haro objects. This increases the total number in the cloud to five. In addition, positions for 5 candidate Herbig-Haro objects are given. Relatively high [S~II]/Hα ratios indicate low excitation conditions for all of these nebulae. We list potential exciting stars for each Herbig-Haro object and candidate by identifying nearby young stellar objects with strong infrared excesses and/or millimeter continuum emission. The location of most of these nebulae near the cloud edges underscores the important role that extinction by dust plays in the ρ Oph cloud in masking the presence of Herbig-Haro objects. Among the newly identified Herbig-Haro objects is a jet-like string of emission nebulae emanating from the classical T Tauri star SR~4. [S~II] emission is also found coincident with a knot of strong molecular hydrogen emission associated with the highly-collimated VLA~1623 molecular outflow. Indeed, the low excitation nature of all of the objects in our study, coupled with the high extinction of the cloud, suggests that a deep survey for shocked molecular hydrogen at λ=2.122 μm would be the best way to search for evidence of strong winds from the large population of young stellar objects in the cloud.

Why it matters

OpenAlex reports 26 citations for this work. Citation counts describe recorded attention and do not establish research quality.

Key contribution

A contribution statement is not available in the OpenAlex record.

Method / approach

Method details are not available in the OpenAlex metadata.

Main findings

Findings are not separately available in the OpenAlex metadata.

Limitations

Limitations are not available in the OpenAlex metadata.

Applications

Application details are not available in the OpenAlex metadata.

Available abstract

Using deep, narrow-band images of the main ρ Oph dark cloud centered on the wavelengths of Hα and [S~II], we present evidence for three new Herbig-Haro objects. This increases the total number in the cloud to five. In addition, positions for 5 candidate Herbig-Haro objects are given. Relatively high [S~II]/Hα ratios indicate low excitation conditions for all of these nebulae. We list potential exciting stars for each Herbig-Haro object and candidate by identifying nearby young stellar objects with strong infrared excesses and/or millimeter continuum emission. The location of most of these nebulae near the cloud edges underscores the important role that extinction by dust plays in the ρ Oph cloud in masking the presence of Herbig-Haro objects. Among the newly identified Herbig-Haro objects is a jet-like string of emission nebulae emanating from the classical T Tauri star SR~4. [S~II] emission is also found coincident with a knot of strong molecular hydrogen emission associated with the highly-collimated VLA~1623 molecular outflow. Indeed, the low excitation nature of all of the objects in our study, coupled with the high extinction of the cloud, suggests that a deep survey for shocked molecular hydrogen at λ=2.122 μm would be the best way to search for evidence of strong winds from the large population of young stellar objects in the cloud.

Key concepts: Herbig–Haro object, Astrophysics, Physics, Astronomy, Young stellar object, Molecular cloud, Stars, T Tauri star

Related papers

Back to paper searchBrowse research topicsOriginal source
Herbig-Haro Objects in the \rho Ophiuchi Cloud — Research Paper | ScholarLens