Agns Acker Strasbourg

1
Cambridge 2006 September 11-13
Workshop on science with new-generation
optical/NIR Galactic Plane surveys Planetary
Nebulae (ionized nebulae)

• Agnès Acker (Strasbourg)
• Quentin Parker (Sydney)
• Brent Miszalski (Sydney-Strasbourg)

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Planetary nebulae / Ionized nebulae
Summary Planetary nebulae as tracers of stellar
populations PN as probes to understand chemical
gradients in the Galaxy Our objectives we need
both south and north surveys Spectroscopy /
imagery a contribution at IPHAS
from the OHP Telescopes 1.2 and 1.5
m Example of 3 Kronenberger objects
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Planetary nebulae good tracers of stellar
populations
Ha, NIII
OIII

• emission concentrated
• in narrow radiations
• Visibles at large distances

Hb
SII
OI

• Final stage of the evolution of stars with low
  masses (lt 8 Msol)
• 90 of all stars in the Galaxy
• ages from a few 108 to 1010 yrs

1/18
4
Planetary nebulae good tracers of stellar
populations

• PN as probes to understand.....
• A gradient within the bulge ?
• - Is the median oxygen abundance in the bulge
  larger
• with respect to that for disk objects ?
• - Is the abundance distribution similar to that
• found by Zoccali et al. (2003) from bulge
  giants ?
• - Do the O/H gradient flatten in the most
  internal parts of the Galaxy, and possibly
  changes sign,
• in agreement with results from abundance
  
• determinations from B-type stars ?
• Górny et al. 2004,
  Todt et al 2004,
• 
  Costa, 2006 (Hawaii)

2/18
5
Planetary nebulae good tracers of stellar
populations

• PN as probes
  to understand...
• A revisited radial gradient
• - The flattening in the gradient at R 10 kpc
• Do the flattening reflects the lower star
  formation rate in the outer part of the disk
  compared to the regions closer to the galactic
  center ?
• Stasinska 2004
• When dynamics of the Galaxy is considered,
• is there a minimum of abundances near the
  corotation radius ?
• Lépine et al. 2002
• - What happens at R 10 kpc (and beyond) ?
•  

3/18
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Planetary nebulae good tracers of stellar
populations
PN as probes
to understand... PN as constraints in
chemodynamical evolution models - Younger PNe
have a flatter radial gradient Is there a time
variation in the gradient ? - Is there a
vertical gradient ? Indications are
contradictory and non-conclusive See Maciel,
Lago Costa 2006, Maciel et al. 2003, Costa,
Uchida Maciel 2003, Escudero, Costa Maciel
2004, Stasinska 2004, Köppen 2005  
4/18
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Planetary nebulae good tracers of stellar
populations

• Our immediate objectives
• Chemical and kinematical study of PN
• in the Bulge and in the discs (thin and
  thick)
•    
• ? compare the properties
• of these galactic populations
•     for longitudes between - 50 and 50
• and latitudes from - 12 to 12
• Special focusing on PN from massive
  progenitors
•   Individual study of selected very large PN
• (Observations planed with FLAMES/VLT,
  AAOmega, Gemini - north)
• ? We need surveys for the whole Galaxy
• (SSH and IPHAS)

5/18
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IPHAS
AAO/UKST H? Survey
6/18
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Galactic distribution of all known PN -
SECGPN, Strasbourg-ESO catalogue (Acker et al.
1992, 1996) - MASH 1 and MASH 2 from AAO/UKST H?
Survey
IPHAS
Brent Miszalski
7/18
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The AAO/UKST H? Survey
233 SHS plates (4²) covering the southern
galactic plane
18 fields covering 15 around the
bulge
8/18
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The IPHAS Survey
Spectroscopy / imagery a
contribution from the OHP
Observatoire de Haute-Provence, France
9/18
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Spectroscopy at the T 1.93 m ?
Carelec spectrograph (Cassegrain focus)
Range 380-750 nm 0.3 nm / px
But. The telescope is devoted to the extrasolar
planets
10/18
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Imagery at the T 1.20 m OHP
Focus Cassegrain Camera CCD - 5 µm/arcsec
Focus Newton F720 cm f/6
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Spectroscopy at the T 1.52m OHP
Focus COUDE F 40,50 m f/27 - 200
microns / arcsec
Aurélie spectrograph Camera CCD (2000 pix)
R from 6 000 to 100 000
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But. Lowest Aurélie Resolution 6000 (
0.05nm/px) ? only 80 nm of spectral range?
region around Ha selected

NII
Ha
NII
SII
OIII
Hb
13/18
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Other bright Lines as Diagnostics

• In these multi-dimensional
  plots,
• differences between systems are easily probed.

LMC
N 4697

• we need (1) more data !
• (2) a confrontation of data with theory in
  multi-dimensional
• emission-line space

From Robin Ciardullo
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Preliminary OHP results 3 faint objects
discovered by Kronenberger
SII 200 sec
U 200 sec
U 30 sec
Kr 21
R 6000 1800 sec
Ha 200 sec
- 59 km/s
images J.F. Soulier July 2006
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Results 3 faint objects from Kronenberger
Te 8
R 6000 1800 sec
U 30 sec
Ha 200 sec
RV - 92 /- 1 km/s.
I(6717)/I(6730) 0,80 ? Density (part/cm3)
1000
images J.F. Soulier July 2006
16/18
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Results 3 faint objects from Kronenberger
KrBN

R 6000 1800 sec
not a typic PN other spectra and images
needed !
Ha
I(NII) / I(Ha) 5.2 I(SII) / I(Ha) 2
I(6717)/I(6730) 0.5 ? ? possibly very high
electron density
17/18
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Tel 1.93 m reserved for extrasolar planets
research
Conclusion on OHP Tel 1.2 m and 1.5
m OK for imagery spectroscopy
But spectrograph Aurelie has short
spectral range ? gt 3 exposures
needed But location price/night
40 (1.2 m) to 240 (1.5
m) ------------------------ OHP could bring a
valuable contribution to the follow-up of the
IPHAS survey
18/18