Detection of C2, CN, and NaID absorption in the AGB remnant of HD56126
| dc.creator | Bakker, Eric J. | |
| dc.creator | Waters, L. B. F. M. | |
| dc.creator | Lamers, Henny J. G. L. M. | |
| dc.creator | Trams, Norman R. | |
| dc.creator | Van der Wolf, Frank L. A. | |
| dc.date | 1995-10-23 | |
| dc.date.accessioned | 2026-07-07T02:20:20Z | |
| dc.date.available | 2026-07-07T02:20:20Z | |
| dc.description | We present the detection of molecular absorption lines in the optical spectrum of the post-AGB star HD56126. The C2 Phillips A^{1}Π_{u}-X^{1}Σ^{+}_{g} (1,0), (2,0), and (3,0); Swan d^{3}Π_{g}-a^{3}Π_{u} (0,0) and (1,0); and CN Red system A^{2}Π-X^{2}Σ^{+} (1,0), (2,0), (3,0), and (4,0) bands have been identified. From the identification of the molecular bands we find an expansion velocity of 8.5+-0.6 kms independent of excitation condition or molecular specie. On the basis of the expansion velocity, rotational temperatures, and molecular column densities we argue that the line-forming region is the AGB remnant. This is in agreement with the expansion velocity derived from the CO lines. We find column densities of log N_C2=15.3+-0.3 cm-2 and log N_CN=15.5+-0.3 cm-2, and rotational temperatures of T_rot=242+-20 K and T_rot=24+-5 K respectively for C2 and CN. By studying molecular line absorption in optical spectra of post-AGB stars we have found a new tracer of the AGB remnant. From comparison with the results of CO and IR observations it is possible to obtain information on non-spherical behavior of the AGB remnant. Using different molecules with different excitation conditions it should be possible to study the AGB remnant as a function of the distance to the star, and thus as a function of the evolutionary status of the star on the AGB. | |
| dc.description | Accepted by A&A main journal, 22 pages plain latex includes 9 postscript figures, uses psfig.sty | |
| dc.identifier | https://arxiv.org/abs/astro-ph/9510122 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/9510122 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/10179 | |
| dc.subject | Astrophysics | |
| dc.title | Detection of C2, CN, and NaID absorption in the AGB remnant of HD56126 | |
| dc.type | text |