Search
References
Cross-match
Download
Acknowledgement
☰
Display data from paper
Data:
OH
GLE01 - OH maser mapping of the evolved star HD 179821: evidence for interacting outflows
Interferometry data
Short title
: Gledhill et al. (2001)
Authors
: Gledhill, T. M. Yates, J. A. Richards, A. M. S.
Journal
: Monthly Notices of the Royal Astronomical Society, Volume 328, Issue 1, pp. 301-310.
Bibcode
:
2001MNRAS.328..301G
Abstract
The evolved star HD 179821 continues to be the subject of much debate as to whether it is a nearby (D=1kpc) post-asymptotic giant branch (post-AGB) star or a distant (D=6kpc) high initial mass (M
i
>=30M
solar
) post-red supergiant. We have mapped the OH maser emission around HD 179821 in the 1612- and 1667-MHz lines with the MERLIN interferometer array at a resolution of 0.4arcsec and 0.35kms
-1
. The OH emission lies in a thick shell with inner and outer radii of 1.3 and 2.9吆
15
m (D=6kpc) and expansion velocity of 30kms
-1
. Although we find some evidence for acceleration and for deviations from spherical symmetry, the bulk of the maser emission is consistent with a constant-velocity spherical shell. The extent of the shell agrees with H
2
O and OH dissociation models and supports a distance estimate of 6kpc. However, the shell is incomplete and appears to have been disrupted by more recent collimated outflow activity within the last 1500yr. We suggest that this activity is also responsible for the active envelope chemistry (in particular the presence of HCO
+
) and for the apparent offset of the star from the centre of the shell. The luminous yellow hypergiant star IRC +10420 also shows signs of recent outflows, and HD 179821 may be at a similar, perhaps slightly earlier, phase of evolution. We suggest that the SiO thermal emission arises from the same detached envelope as the OH maser emission as in IRC +10420. If so then this would strengthen the connection between these two stars and probably rule out a post-AGB status for HD 179821.
Download as
:
Table (CSV)
View paper statistics
Detection table from Gledhill et al. (2001)
Export table to csv
Hide
/
Show
individual components
Non-detection table from Gledhill et al. (2001)
Export table to csv
Hide
/
Show
individual components
Display associated data
IRAS source
IRAS coordinates (RA, Dec)
IRAS flux density (F12,F25,F60,F100)
2MASS source
2MASS coordinates (RA, Dec)
2MASS magnituted (J,H,K)
Variable star
Variable star parameters
Star Formation Region name
Star Formation Region parameters
WISE source
WISE coordinates (RA, Dec)
WISE magnitudes (w1, w2, w3, w4)
Akari IRC source
Akari IRC coordinates (RA, Dec)
Akari IRC fluxes (S09, S18)
Akari FIS source
Akari FIS coordinates (RA, Dec)
Akari FIS fluxes (S65, S90, S140, S160)
View images
DSS (optical)
2MASS (JHK)
WISE (4-22 um)
IRAC (3-8 um)
GLIMPSE 360 (3.6-4.5 um)
PACS color (70-160 um)
SPIRE color (250-500 um)
AKARI color (60-160 um)
NVSS (1.4 GHz)
SDSS (optical+NIR)
Image size
:
arcsec (default is 120 arcsec)
Get selected data
X
Position of H
2
O maser detection
DSS colored
2MASS colored
WISE colored
SDSS color
IRAC color I1,I2,I4
GLIMPSE 360
PACS color (70-160 um)
SPIRE color (250-500 um)
NVSS (1.4GHz)
UKIDSS K
2MASS K