J/ApJ/644/1006 HH 529 spectroscopy (Blagrave+, 2006)
A photoionized Herbig-Haro object in the Orion nebula.
Blagrave K.P.M., Martin P.G., Baldwin J.A.
<Astrophys. J., 644, 1006-1027 (2006)>
=2006ApJ...644.1006B 2006ApJ...644.1006B
ADC_Keywords: H II regions ; Stars, pre-main sequence ; Spectroscopy
Keywords: dust, extinction - H II regions - ISM: Herbig-Haro objects
Abstract:
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 easternmost 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 echelle
spectroscopy, showing that the spectrum of this gas is consistent with
photoionization by theta1 Ori C. By modeling the emission lines, we
determine a gas-phase abundance of Fe that is consistent with the
depleted (relative to solar) abundance found in the Orion
nebula-evidence for the presence of dust in the nebula and therefore in
the Herbig-Haro outflow. The spectrum also allows for the calculation
of temperature fluctuations, t2, in the nebula and the shock. These
fluctuations have been used to explain discrepancies between
abundances obtained from recombination lines versus those obtained
from collisionally excited lines, although to date there has not been
a robust theory for how such large fluctuations (t2>0.02) can be.
Description:
Spectra were obtained using the echelle spectrograph on the 4m Blanco
telescope at the Cerro Tololo Inter-American Observatorycovering the
spectral range from the near-UV (3500Å) to the near-IR (7500Å).
Three sets of red and blue spectra were obtained on two dates in 1997
and 1998.
Objects:
-----------------------------------------
RA (2000) DE Designation(s)
-----------------------------------------
05 35.3 -05 23 HH 529 = HH 529
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 111 443 Summary of double Gaussian fits to observed
echelle spectra
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 F8.3 0.1nm ID ? Wavelength identification (1)
10 A1 --- f_ID [ns] nebular or shock component
12- 19 A8 --- Ion Ion identification
21 A1 --- f_S/N [?] A low S/N (2.6<S/N<5.2) flag
23- 30 F8.3 0.1nm Wave Observed wavelength of line peak (3)
32- 36 F5.1 km/s Vel ? Line velocity
38- 40 F3.1 km/s e_Vel ? Uncertainty in Vel
42- 45 F4.1 km/s FWHM Line Full-Width at Half-Maximum (4)
47- 50 F4.1 km/s e_FWHM Uncertainty in FWHM
52- 59 F8.4 10-16W/m2/arcsec2 Icorr Reddening-corrected
surface brightness (5)
61- 66 F6.4 10-16W/m2/arcsec2 e_Icorr Uncertainty in Icorr (5)
68- 72 F5.1 --- S/N Signal-to-Noise (6)
74- 79 F6.4 --- Ratio ? Shock-to-nebula surface brightness
ratio (Is/In) (7)
81- 86 F6.4 --- e_Ratio ? Uncertainty in Ratio
88-111 A24 --- Notes Additional notes (8)
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Note (1): Wavelength of line, in air. Wavelengths are from the Atomic Line
List v2.04 (http://www.pa.uky.edu/~peter/atomic/, maintained by P.A.M.
van Hoof), except O II from Blagrave & Martin (2004ApJ...610..813B 2004ApJ...610..813B).
Note (3): Adjusted to rest frame of nebular H+ as defined by median of
first six unblended H I Balmer lines.
Note (4): A quoted FWHM of 28.3±0.0 is the result of a constrained
double Gaussian fit.
Note (5): Calculated from the best-fit Gaussian area and its 68.3%
confidence interval. The red shock lines have been adjusted by a
factor of 0.85 to correct for slit coverage differences between the
red and blue spectra. The nebular lines are not adjusted. In units of
10-13erg/s/cm2/arcsec2.
Note (6): From surface brightness and 68.3% confidence interval.
Note (7): The shock-to-nebula ratio is entered within the nebula row
and the shock row is left blank.
Note (8): Additional notes as follows:
C = constrained double Gaussian fit
T = constrained triple Gaussian fit
S = single Gaussian fit
R = red echelle spectrum
B = blue echelle spectrum
avg = average of two orders
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 21-Sep-2007