Herbig-Haro Objects HH 434–436: Part of a Giant Flow Driven by the Central Source A/B of IRAS 04325+2402?

Abstract

While carrying out a wide-field survey of nearby star-forming regions for Herbig-Haro (HH) objects we discovered three Herbig-Haro objects, HH 434-436, in a similar to2' x 2' (0.08 x 0.08 pc) region near L1536. HH 434 consists of three knots. HH 435 shows a bow shock shape, and HH 436 is an elongated patch. Spectroscopic observations indicate that the excitation levels of HH 434-436 are different : HH 436 has a high excitation level, while 434A has an intermediate, and 435 has a low excitation level. The overall morphology of HH 434-436 shows a bow shock shape and suggests that HH 434-436 may be a single bow shock fragmented into separate knots. Near-infrared observations of the region in the JHK' broad bands and H-2 upsilon = 1-0 S(1) narrow band were also carried out, but no embedded source was detected. The overall bow shock of HH 434-436 points back toward an embedded multiple system, IRAS 04325+2402. Moreover, from Hubble Space Telescope Near Infrared Camera and Multi-Object Spectrometer 3 observations HH 434-436 are located on the expected outflow axis of the central source A/B of this multiple system. On the basis of these facts we propose that HH 434-436 may be driven by the central source A/B of IRAS 04325+2402; therefore, they are probably part of a giant HH flow, which has a scale of 2.4 pc, although the possibility that HH 434-436 are three distinct flows cannot be completely ruled out.