Issue |
A&A
Volume 407, Number 1, August III 2003
|
|
---|---|---|
Page(s) | 51 - 59 | |
Section | Extragalactic astronomy | |
DOI | https://doi.org/10.1051/0004-6361:20030732 | |
Published online | 17 November 2003 |
The Local Group Census: Planetary nebulae in IC 10, Leo A and Sextans A*
1
Dipartimento di Astronomia e Scienza dello Spazio, Universitá di Firenze, L.go E. Fermi 2, 50125 Firenze, Italy
2
Isaac Newton Group of Telescopes, Apartado de Correos 321, 38700 Santa Cruz de La Palma, Canarias, Spain
3
Instituto de Astrofísica de Canarias, c. vía Láctea s/n, 38200, La Laguna, Tenerife, Canarias, Spain
4
School of Pure and Applied Physics, Queen's University Belfast, Belfast BT7 9NN, Northern Ireland, UK
5
ST-ECF, ESO, Karl-Schwarzschild-Strasse 2, 85748 Garching bei München, Germany
6
Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK
7
Physics Department, UMIST, PO Box 88, Manchester M60 1QD, UK
Corresponding author: R. Corradi, rcorradi@ing.iac.es
Received:
28
March
2003
Accepted:
6
May
2003
In the framework of our narrow-band survey of the Local
Group galaxies, we present the results of the search for planetary
nebulae (PNe) in the dwarf irregular galaxies
IC 10, Leo A and Sextans A.
Using the standard on-band/off-band technique, sixteen new candidate
PNe have been discovered in the closest starburst galaxy, IC 10. The
optical size of this galaxy is estimated to be much larger than
previously thought, considering the location of the new PNe in an area
of 3.6 kpc 2.7 kpc. We also confirm the results of previous
studies for the other two dwarf irregular galaxies, with the detection
of one candidate PN in Leo A and another one in Sextans A. We review the
number of planetary nebulae discovered in the Local Group to date and
their behaviour with metallicity. We suggest a possible fall in the
observed number of PNe when [Fe/H] ≪ –1.0, which might indicate that
below this point the formation rate of PNe is much lower than for
stellar populations of near Solar abundances. We also find
non-negligible metallicity effects on the [O iii] luminosity of the
brightest PN of a galaxy.
Key words: planetary nebulae: general / galaxies: individual: Leo A, Sextans A, IC 10
© ESO, 2003
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.