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Nomenclature revisited

Nomenclature revisited. No more than 5 mins or so on this From yesterday and subsequent feedback it is clear that many here are: Keen to take this opportunity to try to progress this vexing problem Keen to avoid foreign telephone numbers Like the idea of simplicity

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Nomenclature revisited

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  1. Nomenclature revisited • No more than 5 mins or so on this • From yesterday and subsequent feedback it is clear that many here are: • Keen to take this opportunity to try to progress this vexing problem • Keen to avoid foreign telephone numbers • Like the idea of simplicity • Appreciate the need to identify objects as PN associated with a particular galaxy • It would be GREAT to take something away from this meeting

  2. Assumptions • Let us assume any host galaxy will ALWAYS have a name (even if we have to make up a new one) • Let us assume that any object can also have an alternative name associated with a given project or team – after all egos need to be catered for • BUT each object ALSO adheres to OUR new Universal PN Locator (UPL) for extragalactic PN • Let us assume that the CDS will be happy with our preferred new UPL nomenclature • As usual the devil is in the detail…

  3. Problems • Objects subsequently identified as contaminants • In a numbered scheme 1-n a removed object `m’ will leave a gap in what may been a nice ordered sequence • It does’nt matter! • Even in commercial data-bases such gaps are quite acceptable and common

  4. Problem #2 Intracluster PN • How do we name them? • Some suggestions • Attach them to closest named galaxy • Include additional `IC’ to PN e.g. • PNIC-NGC7793-2415 or PN-ICNGC7793-2415 • Just have PN-NGC7793-2415 • Include the constellation in the name instead of a galaxy? • Where does a galaxy end and intergalactic medium begin? • Note any IC PN associated with free-floating GC’s or whatever would still work IF assume GC’s have a name

  5. Problem #3 special cases • They always crop up! • We will not satisfy everyone with ANY adopted system • There is probably no perfect scheme • If we are 90% there that would be a result. • So…………??? • PN-M31-1 to PN-M31-2786 or • PN GM31JHHMMSSss(s)+/-DDMMSSs(s) • Or something else? • We can decide

  6. Observational challenges Q.A.Parker (Macquarie University/AAO)

  7. The discussion…. • Just a brief (relatively), simple pre-amble to get the discussion going • In fact at this stage I rather like the idea of somewhat chaotic (not too chaotic) discussion • Let’s see what might emerge before we settle down and consider more specific questions on Friday during Dick’s afternoon discussion session….. • So lets use this time to frame some questions for tomorrow and I’ll show some specific prepared questions from Dick at the end

  8. Fainter, Finer, Further, FasterFull coverage & Feory Fainter Full coverage Finer Technology Faster Further

  9. Basic science • PNLF as standard candle • PN as Dynamical tracers • PN as laboratories of nebula physics and comparison with theory • Abundance variations and gradients within and between stellar systems • Stellar evolution of low & intermediate mass stars • PN-ISM interaction • And plenty of other stuff!

  10. Technology • This both dictates and limits what we can observationally achieve at any given epoch and in any wavelength domain • It is at the HUB of the challenge wheel • It creates the spokes which enable us to tackle all these issues • Q: Are we driving it or is it driving us? • Can we influence design/instrumentation to suit our needs? • What route are we taking on the science road? • This depends on who is behind the wheel and the quality of the map! • This discussion is about trying to get a good map! • Of course there are many drivers, in different cars some in the same race some on a totally different route altogether!

  11. Technology • Larger/multi aperture telescopes of all kinds • Multi-wavelength capabilities from earth and space UV/Opt/IR/radio • Higher resolution capabilities • More efficient/powerful detectors, spectrographs, interferometers • Fibre/IFU/multi-slit technologies combined with narrow band capabilities, innovative techniques (e.g. nod and shuffle, tunable filters) • The next big thing we have’nt thought of yet!

  12. The Planetary Nebula Spectrograph

  13. Do we want more of these? • More with better resolution and wavelength coverage? • What about tunable filters that can rapidly image a series of diagnostic nebular lines over a wide field at a given redshift that can then be phased through the entire depth of a cluster…. • TTF on the AAT was a start but although a powerful and unique capability it has been de-commissioned

  14. The observational challenge…. • AIM: To be able to obtain for external PN the kinds of observational detail we find in our own Galaxy: • High S/N, high resolution spectra permitting accurate nebular parameters to be determined across a wide wavelength range • Accurate radial velocities/expansion velocities • High quality imaging (in lines) across a wide wavelength regime – data-cubes • Fine tune theory/models with detailed observations of diverse PN populations in widely different environments

  15. Specifics • Optical: IFU’s, FLAMES, GIRAFFE, 2dF etc • Active and Adaptive optics (optical/NIR) • New facilities: Spitzer, VISIR, CRIRES • Future facilities:SKA, OWL, JWST +++ • Faster computers more powerful, precise and sophisticated n-body simulations and photoionisation codes • What else do we want??

  16. Fainter • IF we simply probe fainter via a combination of LGP, system efficiency gains, AO and exposure times we can: • Push PNLF to limits is external galaxies at greater distance • Obtain higher S/N for more useful nebular diagnostic lines in our own galaxy, LMC and local group and perhaps begin to sample more basic lines in more distant galaxies • Abundance determinations in systems >10Mpc • Detection of halos, additional morphological features, lower surface brightness PNe…

  17. Fainter…………. New ID due to lobes being seen for first time - “the Wing-nut” –was a compact `point symmetric’ PN…. ID in PK catalogue followed up by Acker and removed

  18. What you first see isn’t necessarily what you get

  19. Nebula spectroscopy

  20. Finer Resolution • Both in imaging and spectroscopically and across wider wavelength domain • Ability to discriminate finer morphological detail • Measure accurate expansion velocities and systemic velocities in external systems • Reaction interfaces with ISM • Removal of contaminants in spectra that were overlapping in lower res systems

  21. PNe halos

  22. Faster! • We are truly entering an era of the data avalanche in many branches of science • AVO/Astrogrid initiatives to federate/incorporate/manage these massive petabyte catalogues, data points, images etc etc • Coupled with vast storage and processing capabilities as technology and Moores law allows • We need to be able to handle/understand and disseminate results in a timely fashion and easily relate one sample to another • In the PN field, particularly in the extragalactic domain, we will soon have tens of thousands of individual PN crying out for further study

  23. Further • Problems • Extreme faintness • Only visible as point sources in all but closest neighbours with current technology • Contamination

  24. In distant PN we would like to: • Detect/study Central stars • Detect/study Outer halos • Detect highly evolved examples • Determine PN morphologies • Determine nebular abundances • All in increasingly remote galaxies

  25. Some desires picked up from this meeting • Badly need better/any spectra of PN candidates in Intracluster medium • Also need better simulations to leverage observations • Want to determine multi-dimensional PNLF’s • Want to detect central stars and directly determine spectral and photometric properties

  26. A brief `hot of the telescope’ presentationOrtwin Gerhard

  27. Specific Questions (Dick Shaw)these will be discussed on Friday afternoon • What are the key scientific EGPN questions to address? • What tools and techniques are needed to address them? • Can these issues best be tackled by large collaborations?

  28. Should we aim for: • Complete census of PN in Local Group to >5mags below peak L(5007)  understand origins of PNLF, late type populations, SFH • Wide field imaging: FPA with selected filters or special imaging spectrographs (e.g. PN.S); IFU’s

  29. Can we perform: • Morphological studies of complete samples of PN in at least 2 local group galaxies • E.g. via HST/STIS or MCAO on 8m’s • Census of intra-cluster PNe + velocities  understand galaxy dynamics, IC stellar population • Wide field imaging (FPA) with narrow & intermediate-band filters

  30. Surveys • Survey for Miras, Carbon stars in nearby galaxies • Synoptic Time-domain surveys • UV spectroscopic surveys of the LG PNe to understand C production in late stages of stellar evolution HST/STIS and any future UV space mission(s)

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