Galactic Planetary Nebulae in the AKARI Far-Infrared Surveyor Bright Source Catalog (original) (raw)

Planetary nebulae near the Galactic center: Identifications

Astronomy and Astrophysics, 2004

We surveyed the central 4 x 4 degrees of the Galactic center for planetary nebulae in the light of [S III] λ9532 and found 94 PNe that were not previously known, plus 3 that were previously identified as possible candidates. For 63 of these 97 objects, we obtained spectra that are consistent with highly reddened PN while the other 34 could not be recovered spectroscopically and remain unverified. Of the 94 candidates, 54 and 57 were detected via radio at 3 and 6 cm, respectively. An additional 20 PNe candidates were found during follow-up Hα imaging but have not yet been verified spectroscopically. Based on the properties of IRAS sources in this region of the Galaxy, and on the total luminosity of the Galactic bulge, the expected number of PNe is ∼ 250, only 50% more than the 160 PNe candidates now known. Thus, surveys for PNe in the bulge are approximately two-thirds complete with the remainder likely hidden behind dust.

c © ESO 2009 Astronomy &Astrophysics Candidate planetary nebulae in the IPHAS photometric catalogue

2009

Context. We have carried out a semi-automated search for planetary nebulae (PNe) in the INT photometric H-alpha survey (IPHAS) catalogue. We present the PN search and the list of selected candidates. We cross correlate the selected candidates with a number of existing infrared galactic surveys in order to gain further insight into the nature of the candidates. Spectroscopy of a subset of objects is used to estimate the number of PNe present in the entire candidate list. Aims. The overall aim of the IPHAS PN project is to carry out a deep census of PNe in the northern Galactic plane, an area where PN detections are clearly lacking. Methods. The PN search is carried out on the IPHAS photometric catalogue. The candidate selection is based on the IPHAS and 2MASS/UKIDSS colours of the objects and the final candidate selection is made visually. Results. From the original list of ∼600 million IPHAS detections we have selected a total of 1005 objects. Of these, 224 are known objects, leavin...

HASH: the Hong Kong/AAO/Strasbourg Hα planetary nebula database

By incorporating our major recent discoveries with re-measured and verified contents of existing catalogues we provide, for the first time, an accessible, reliable, on-line SQL database for essential, up-to date information for all known Galactic planetary nebulae (PNe). We have attempted to: i) reliably remove PN mimics/false ID's that have biased previous studies and ii) provide accurate positions, sizes, morphologies, multi-wavelength imagery and spectroscopy. We also provide a link to CDS/Vizier for the archival history of each object and other valuable links to external data. With the HASH interface, users can sift, select, browse, collate, investigate, download and visualise the entire currently known Galactic PNe diversity. HASH provides the community with the most complete and reliable data with which to undertake new science. 1. Introduction PNe, the ejected, ionised shrouds of dying stars, are a complex and brief (∼25,000 year) phase of late stellar evolution. They offer rich science as vital probes of stellar nucleosynthesis processes in mid to low-mass stars. These stars make-up 90% of all stars above 1 solar mass. They provide a detectable, fossil record of stellar mass loss off the AGB/post-AGB and are powerful tracers of our Galaxy's star-forming history. Furthermore, they are useful kinematical probes visible to large Galactic distances due to their rich, strong, emission line spectra. These scientific levers and others encourage the search for and study of PN in our own and other Galaxies. We are currently in a golden age of PN discovery. New high sensitivity, wide-field, narrow-band, Galactic plane surveys undertaken on the UK Schmidt Telescope in Australia [1][2], the Isaac Newton telescope on La Palma [3] and now the ESO/VST in Chile [4] have facilitated this. These Hα surveys have provided significant Galactic PNe discoveries that have more than doubled the totals accumulated by all telescopes over the previous 260 years, e.g. [5][6][7][8] and these proceedings, including posters by Kronberger et al. and Acker et al. Most new PNe found are more redenned, evolved and of lower surface brightness than previous compilations such as [9][10] and [11] while others are faint but compact and more distant. The scope of any future large-scale PNe studies, particularly those of a statistical nature or undertaken to understand true PNe diversity and evolution, should now reflect this fresh PN population landscape. Studies should make us of the combined sample of ∼3500 Galactic PNe now available in our HASH database. HASH takes into account recent major discoveries and the power invested in the wide-field, high sensitivity, high resolution, multi-wavelength imaging surveys now available across much of the electromagnetic spectrum.

Planetary nebulae and how to find them: A concise review

Frontiers in Astronomy and Space Sciences

This review provides useful background and information on how we find, vet and compile Planetary Nebulae (PNe) candidates and verify them. It presents a summary of the known Galactic PNe population and their curation in the Hong Kong/AAO/Strasbourg/Hα PNe catalogue, “HASH”. It is a simple introduction for anyone interested in working with PNe, including postgraduate students entering the field and for more general interest too.

New Galactic Planetary nebulae selected by radio and multiwavelength characteristics

Monthly Notices of the Royal Astronomical Society

We have used the Cornish radio catalogue combined with the use of multiwavelength data to identify 62 new Planetary Nebula (PN) candidates close to the Galactic mid-plane. Of this sample 11 have weak optical counterparts in deep narrow band Hα imaging that allows their spectroscopic follow-up. We have observed eight of these candidates spectroscopically, leading to the confirmation of 7 out of 8 as PNe. All but one of our sample of newly detected PNe appear to be of Type I chemistry with very large [NII]/Hα ratios. This indicates that our selection method heavily favours detection of this kind of PN. Cornish is a low Galactic latitude survey where young objects and Type I PNe (thought to derive from higher mass progenitors) are more plentiful, but where optical extinction is large. The very high success rate in correctly identifying PNe in this zone proves the efficacy of our radio and multiple multi-wavelength diagnostic tools used to successfully predict and then confirm their PN nature, at least in the cases where an optical counterpart is found and has been observed. The study reinforces the effective use of a combination of multi-wavelength and optical data in the identification of new Galactic PNe and especially those of Type I chemistries whose dusty environments often prevents their easy detection in the optical regime alone.

Milky Way and Magellanic Cloud Surveys for Planetary Nebulae

Proceedings of the International Astronomical Union

The recent on-line availability of large-scale, wide-field surveys of the Galaxy and Magellanic Clouds in several optical and near/mid-infrared passbands has provided unprecedented opportunities to refine selection techniques and eliminate contaminants in PN surveys. This has been coupled with new surveys offering improved detection rates via higher sensitivity and resolution. This will permit more extreme ends of the PN luminosity function to be explored and enable studies of under represented PN evolutionary states. Known PNe in our Galaxy and LMC have thus been significantly increased over the last few years due primarily to the advent of narrow-band imaging in important nebula lines such as Hα, [O iii] and [S iii]. These PNe are generally of lower surface brightness, larger angular extent, in more obscured regions and in later stages of evolution than those in most previous surveys. A more representative PN population for in-depth study is now available, particularly in the LMC where the known distance adds considerable utility for derived PN parameters. Future prospects for Galactic and LMC PNe research are briefly highlighted.

Candidate planetary nebulae in the IPHAS photometric catalogue

Astronomy and Astrophysics, 2009

Galactic Planetary Nebulae in the AKARI Far-Infrared Surveyor Bright Source Catalog (original) (raw)

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