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J/ApJ/478/603   New Herbig-Haro flows in L1448 and L1455     (Bally+ 1997)

New Herbig-Haro flows in L1448 and L1455 Bally J., Devine D., Alten V., Sutherland R.S. <Astrophys. J. 478, 603 (1997)> =1997ApJ...478..603B
ADC_Keywords: Stars, pre-main sequence ; Radial velocities Keywords: ISM: individual (L1448) - ISM: jets and outflows - stars: pre-main-sequence Abstract: We present a deep narrowband Hα and [S II] optical survey of a roughly 1deg2 region containing L1448 and L1455 in the southwestern region of the Perseus molecular cloud. We report the detection of 13 new groups of Herbig-Haro (HH) objects in this region. The L1448 core contains eight groups of Herbig-Haro objects (HH 193, HH 194, HH 195, HH 196, HH 197, HH 267, HH 268, and HH 277). Many of the new HH objects near L1448 have orientations similar to the L1448C molecular jet and L1448 IRS3 outflow. All four known infrared sources in L1448 power Herbig-Haro objects. L1448 IRS 1 is the likely source of HH 194, HH 195E, and possibly HH 268. L1448 IRS 2 drives HH 195, and L1448 IRS 3 may power HH 196 and possibly HH 193. HH 267 and HH 277 lie close to the axes of the IRS 2 and IRS 3 flows and may also be powered by one of these sources. Finally, the class 0 source L1448C powers HH 197. The L1455 core contains five new groups of HH objects (HH 278, HH 279, HH 280, HH 317, and HH 318). L1455 IRS 1 and L1455 IRS 2 are likely to power HH objects, but a unique association between each IRAS source and a specific HH object is difficult to make. Both clouds contain some HH objects whose driving sources cannot be conclusively identified. Most of the new HH objects are located near the cloud edges while some are in the interclump medium (ICM) more than 1pc from the nearest cloud core or known young stellar object. These observations provide further evidence that HH flows can extend far beyond the cloud cores containing their sources, and in some cases extend over greater distances than associated high-velocity millimeter-wavelength CO emission. Herbig-Haro objects associated with the terminal working surfaces of outflows located in the ICM can be used to probe the nature of the interclump gas in molecular clouds. The large number of HH objects found in relatively inactive star forming regions such as L1448 and L1455 indicates that shock heating and acceleration by protostellar outflows plays an important role in determining the ionization state and energetics of the ICM that surrounds low-mass star forming regions. Description: Images covering the region to the northwest of L1448 were obtained on 1993-11-01 with the 0.9m f/7.5 Cassegrain telescope Kitt Peak National Observatory (KPNO) with a Tektronix 2048x2048 pixel CCD (T2KA) which has a pixel scale of 0.68arcsec/pix and a total field of view of about 23arcmin. Observations in Hα used a narrowband filter centered at 656.2nm (3nm wide) and 674.5nm (8.3nm wide) for 671.6 and 673.1nm [SII] lines. The fields between L1448 and L1455 were observed wth the 1m reflector at the Mount Laguna observatory operated by San Diego State University on 1994-11-16, with a Loral 2048x2048 pixel CCD, and interference filters of width 7nm centered at 673nm ([SII]), 656.3nm Hα), and 665nm (continuum); the field of view is 13arcmin. Images covering roughly 1sq.deg ontaining L1448 and L1455 were obtained with the 0.6m Burrell Schmidt camera at KPNO on 1996-12-16, with a SITE 2048x2048 pixel CCD (2arcsec/pix) and interefernce filters centered on the Hα and [SII] lines with width=8nm. High-resolution spectra (R∼6000) were obtained with the 4m Mayall reflector at KPNO on 1994-11-12/14 and 1996-01-11 using both a 2x5'' slit and a multiaperture slitlet mask on the spectrograph, which gave a scale of 0.54Å/pix (24km/s resolution). File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 76 24 L1448 HH objects table2.dat 76 11 L1455 HH objects
Byte-by-byte Description of file: table1.dat table2.dat
Bytes Format Units Label Explanations
1- 2 A2 --- --- [HH] 4- 6 I3 --- HH HH identification number 7 A1 --- m_HH [ABCDE] Multiplicity index on HH 9 I1 h RAh Right ascension (1950) 11- 12 I2 min RAm Right ascension (1950) 14- 17 F4.1 s RAs Right ascension (1950) (1) 20- 21 I2 deg DEd Declination (1950) 23- 24 I2 arcmin DEm Declination (1950) 26- 27 I2 arcsec DEs Declination (1950) (1) 30- 33 F4.1 aW/m2 Ha Halpha flux (2) 36- 39 F4.1 aW/m2 [SII] ? [SII] flux (671.6+673.1nm) (2) 42- 45 I4 arcsec+2 Area Area of the source 48- 50 I3 km/s RV ? Radial velocity of the HH object 53- 55 I3 km/s DV ? Line width of the HH object 58- 76 A19 --- Notes Remarks about the source
Note (1): Coordinates are accurate to within a few arcseconds. Note (2): Line fluxes are in units of 10-15ergs/cm2/s and were calibrated by observations of the standard star Feige 34. Fluxes were determined by integrating the emission (summing the counts in each pixel) over the apparent extent of the HH object, then subtracting the background integrated over a nearby region of the same size that was free from HH emission.
History: * 03-Oct-1997: Prepared via OCR at CDS. * 03-Jul-2014: Standardized at CDS
(End) James Marcout, Patricia Bauer [CDS] 03-Oct-1997
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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