43 research outputs found
TUIMP: The Universe In My Pocket. Free astronomy booklets in all languages
TUIMP (www.tuimp.org) is an international project to produce little astronomy
booklets. These booklets, folded from just one sheet of paper, can be used in
classrooms, at open public conferences, or during visits of observatories and
planetariums. They are free to download from the internet, the only thing which
is needed is a color printer (in absence of a printer, the booklets can also be
directly consulted on line, even with just a mobile phone). The booklets are
intended for children from nine years old and for anyone curious of astronomy.
They are written in a simple language, amply illustrated, revised and
translated by professional astronomers. So far, they are being published in six
languages, others languages are to come. Everyone is invited to download the
booklets and use them in their outreach activities.Comment: to be published in the proceedings of the CAP2018 conference
Communicating astronomy with the public in Fukuoka, Japa
Planetary nebulae in M32 and the bulge of M31: Line intensities and oxygen abundances
We present spectroscopy of planetary nebulae in M32 and in the bulge of M31
that we obtained with the MOS spectrograph at the Canada-France-Hawaii
Telescope. Our sample includes 30 planetary nebulae in M31 and 9 planetary
nebulae in M32. We also observed one H II region in the disk of M31. We
detected [O III]4363 in 18 of the planetary nebulae, 4 in M32 and 14
in the bulge of M31. We use our line intensities to derive electron
temperatures and oxygen abundances for the planetary nebulae.Comment: 17 pages, 12 figures, accepted by Astronomy & Astrophysics Supplement
Serie
A VLT study of metal-rich extragalactic H II regions. I. Observations and empirical abundances
We have obtained spectroscopic observations from 3600 Angstrom to 9200
Angstrom with FORS at the Very Large Telescope for approximately 70 H II
regions located in the spiral galaxies NGC 1232, NGC 1365, NGC 2903, NGC 2997
and NGC 5236. These data are part of a project aiming at measuring the chemical
abundances and characterizing the massive stellar content of metal-rich
extragalactic H II regions. In this paper we describe our dataset, and present
emission line fluxes for the whole sample. In 32 H II regions we measure at
least one of the following auroral lines: [S II]4072, [N II]5755, [S III]6312
and [O II]7325. From these we derive electron temperatures, as well as oxygen,
nitrogen and sulphur abundances, using classical empirical methods (both
so-called "Te-based methods" and "strong line methods"). Under the assumption
that the temperature gradient does not introduce severe biases, we find that
the most metal-rich nebulae with detected auroral lines are found at
12+log(O/H)~8.9, i.e. about 60% larger than the adopted solar value. However,
classical abundance determinations in metal-rich H II regions may be severely
biased and must be tested with realistic photoionization models. The
spectroscopic observations presented in this paper will serve as a homogeneous
and high-quality database for such purpose.Comment: Accepted for publication in Astronomy and Astrophysic