P. Kajdic,1,2 B. Reipurth,3 A. C. Raga,4 and J. Walawender3
1 Departamento de Ciencias Espaciales, Instituto de Geofísica, Universidad Nacional Autónoma de México, 04510 México, D. F. Mexico. (primoz@geofisica.unam.mx).
2 Instituto de Astronomía, Universidad Nacional Autónoma de México, México.
3 Institute for Astronomy, University of Hawaii, 640 North A'ohoku Place, Hilo, Hawaii 96720–2700, USA. (reipurth@ifa.hawaii.edu, joshw@ifa.hawaii.edu).
4 Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Apdo. Postal 70–543, 04510 México, D. F., Mexico. (raga@nucleares.unam.mx).
Received 2009 August 6 ]]> Accepted 2009 November 5
RESUMEN
En este trabajo estudiamos objetos Herbig–Haro ubicados en la región alrededor de la cabeza del glóbulo cometario CG 30. Se presentan dos conjuntos de imágenes ópticas. El primero consta de imágenes obtenidas con el New Technology Telescope de 3.5 m en 1995 en tres líneas de emisión: Hα, [SII]λλ6731,6716 Å y [O II]λ3729 Å. El segundo conjunto es la imagen en Hα del complejo CG 30/31/38 obtenida en 2006 con el Telescopio Subaru de 8 m. Se ha estudiado los movimientos propios usando las imágenes en Hα de ambas épocas. Debido a la alta resolución de nuestras imágenes hemos podido, por primera vez, resolver el objeto HH 120 en diez nudos y medir movimientos propios para algunos de ellos. Hemos descubierto varios nuevos objetos HH que se ven mejor en nuestra imagen en [SII], como también un gran chorro bipolar, HH 950, que sale de la cabeza de CG 30. Proponemos que dos fuentes submilimétricas previamente conocidas emiten los flujos HH 120 y HH 950. Las dos fuentes podrían ser objetos binarios. Esto se debe a que (1) los vectores de movimiento propio de los nudos de HH 120 sugieren que este objeto está compuesto de dos flujos y (2) la estructura del flujo HH 950 sugiere que la dirección del eje del chorro ha cambiado en el pasado.
ABSTRACT
In this work we study Herbig–Haro objects located in the region around the head of the cometary globule CG 30. Two sets of optical images are presented. The first set was obtained with the 3.5 m New Technology Telescope in 1995 in three emission lines: Ha, [S II]λλ6731,6716 Å and [O II]λ3729 Å. The second set is an Ha image of the CG 30/31/38 complex obtained in 2006 with the 8 m Subaru telescope. A proper motion study of the HH objects in the region was performed using the Ha images from both epochs. Due to the high resolution of our images we were able, for the first time, to resolve the HH 120 object into ten knots and measure proper motions for some of them. We discovered several new HH objects which are best seen in our [S II] image as well as a large bipolar jet, HH 950, emerging from the head of CG 30. We suggest that two previously known submillimeter sources are the driving sources for the HH 120 and HH 950 flows. They could both be binary sources, because (1) the proper motion vectors of the HH 120 knots suggest that this object is actually composed of two outflows and (2) the structure of the HH 950 flow suggests that the direction of the jet axis has changed in the past.
Key Words: ISM: globules — ISM: jets and outflows — ISM: Herbig–Haro objects — stars: formation.
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]]>ACKNOWLEDGMENTS
We are grateful to an anonymous referee for a very careful and helpful report. We thank Ralf Launhardt for providing the accurate positions of the sub–millimeter sources and Klaus Hodapp for providing us with the original infrared image of the CG 30. Primoz Kajdic acknowledges the Dirección General de Estudios de Posgrado of the Universidad Nacional Autónoma de México for a scholarship supporting his graduate studies. This study has been supported by the NSF through grant AST0407005. This material is based upon work supported by the National Aeronautics and Space Administration through the NASA Astrobiology Institute under Cooperative Agreement No. NNA04CC08A issued through the Office of Space Science.
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