1999AJ....117..974C


Query : 1999AJ....117..974C

1999AJ....117..974C - Astron. J., 117, 974-980 (1999/February-0)

The density, extinction, and excitation characteristics of NGC 6445.

CUESTA L. and PHILLIPS J.P.

Abstract (from CDS):

We have acquired [O III] λ5007, H I λλ6563 and 4861, and [S II] λλ6717 and 6731 imaging of the bipolar outflow source NGC 6445. As a result, we find that density is preferentially enhanced within an interior optical/radio emission annulus and takes a maximum value ∼1.1x103 cm–3. Visual extinction appears also to be enhanced within this regime, taking values ∼0.8 mag greater than for the enveloping shell, a result that is shown to imply ratios Av/N(H2) comparable to that of NGC 7027 and at least 4 times greater than for the interstellar medium. Finally, we investigate the variation of excitation through the projected nebular envelope. While the nucleus possesses excitation properties consistent with normal (radiatively excited) sources, it appears that line ratios toward the source periphery may indicate the presence of appreciable shock activity.

Abstract Copyright: ∼

Journal keyword(s): ISM: Dust, Extinction - ISM: Kinematics and Dynamics - planetary nebulae: individual (NGC 6445)

Simbad objects: 2

goto Full paper

goto View the references in ADS

Number of rows : 2
N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2026
#notes
1 NGC 6445 PN 17 49 15.0282384611 -20 00 34.159640072   18.9       ~ 302 0
2 NGC 7027 PN 21 07 01.571952 +42 14 10.47120   10.358 8.831 10.157   ~ 2541 1

To bookmark this query, right click on this link: simbad:objects in 1999AJ....117..974C and select 'bookmark this link' or equivalent in the popup menu