Morphological classification of new candidate PNe in an

Morphological classification of new candidate PNe in an IPHAS sample Kerttu Viironen IAC Collaboration: A. Mampaso (IAC) R. Corradi (ING, IAC), R. Greimel (Cambridge), L. Sabin (IAC) IPHAS collaboration

Overview: 1) PN morphology; introduction 2) IPHAS survey 3) Searching for PNe from IPHAS data 3) Morphology of the PN candidates at 18 h-20 h

PN morphology; introduction - PNe present various morphologies: - Elliptical, Bipolar, Point-Symmetric, Irregular, Stellar (Schwarz et al. 1992; classes author dependent) - Morphology connected to - abundances (bipolars overabundant in He, N; Corradi & Schwarz 1995) - location in Galaxy (median galactic latitude increase from bipolars to ellipticals and to rounds; Manchado & Villaver 2000) - central star properties (bipolars more massive progenitors; Corradi & Schwarz 1995) - All this should be explained theoretically; constraints theories

IPHAS survey Collaboration: ING, La Palma: Corradi, Leisy, Lennon, Skillen UK: Aungwerojwit (Warwick), Barlow, Hales, Wright (UCL), Drew (PI), Unruh (Imperial), Evans (ATC), Gaensicke (Warwick), Greimel, Irwin, Walton (Io. A), Knigge, Witham (Southampton), Morris, Phillipps (Bristol), Vink (Keele), Zijlstra (Manchester) Spain (IAC): Mampaso, Martin, Rodríguez-Flores, Rodríguez-Gil, Sabin, Viironen The Netherlands (Nijmegen): Groot, Morales-Rueda, van den Besselaar USA (Cf. A): Drake, Sokoloski & Steeghs (Cf. A) Australia (AAO/Macquarie): Parker

IPHAS survey IPHAS = the INT/WFC Photometric H Survey of the Northern Galactic Plane Area: all l in Northern Plane; – 5° < b < +5° (1800 deg 2) Mag. limit: ~ 20 in r’ Observations: 2. 5 m Isaac Newton Telescope (La Palma) + Wide Field Camera (4 -CCD mosaic, 2048 x 4200 pix, fov 34 x 34 arcmin 2, 0”. 33 pix-1) H (120 sec), Sloan r’ (30 sec) and i’ (10 sec) at two closely overlapped pointings per field

IPHAS survey A map of the sky: IPHAS survey area shown in green

IPHAS survey Analysis: Pipeline reduction and point-source photometric and astrometric catalogue generation by CASU. IPHAS data are available immediately to astronomers from UK, Spain and the Netherlands, and to ALL astronomers after 1 year from the date of observing. IPHAS web page: http: //www. iphas. org IPHAS overview: Drew et al. 2005, MNRAS , 362, 753 Other IPHAS related papers: see the IPHAS webpage!

The PN search IPHAS - There about 2000 PNe known in. Shiode et al. 2006 the Galaxy - Several hundreds are expected to be found by IPHAS - IPHAS goes deep → faint and/or distant PNe explored Search techniques: 1. Semi-automatic technique: photometric catalogue (r’-H colors) compact/small nebulae 2. visual inspection of mosaics medium/large nebulae

The PNe search; compact PNe E(B-V) giants r’-H Synthetic photometry constructed using Pickles (1998) library of flux-calibrated stellar spectra main sequence supergiants r’-i’ Drew et al. 2005

The PNe search; compact PNe Known PNe in IPHAS two-color diagram

The PNe search; compact PNe - Noise and saturated objects filtered out as well as the detection close to the borders of the CCDs or areas of bad pixels - Objects should be detected at least in Hα and r’ (matching distance 1 arcsec) - Object should be detected at least twice - The magnitude in Hα < 19. 5

The PNe search; compact PNe Final selection made visually (so far only 18 h-20 h region complete!) Automatically selected objects at 18 h-20 h + known PNe Total: 56314 objects 810 ed i stud (H M ied, ud 3 st ied 61 tud s not α) < 17

The PNe search; extended PNe Visual search from IPHAS r’ – Hα mosaics: - 15 x 15 pixel binning for lowest surface brightness nebulae - 5 x 5 pixel binning for intermediate size nebulae The three methods overlap → more complete

Candidate PNe in the IPHAS area at 18 h – 20 h region: 389 objects found 100 of these are known PNe 289 new candidate PNe - 133 with “clear morphology” → considered in the morphological study - 37 unresolved/barely resolved)

Morphology of the PNe/PN candidates Our study (133 candidate PNe in the galactic plane): Corradi & Schwarz 1995 (359 southern PNe):

Morphology of the PNe/PN candidates Our study (133 PNe in the galactic plane): Manchado & Villaver 2000 (<255 PNe in the galactic plane):

Conclusions - IPHAS is greatly increasing the number of northern Galactic PNe - We find a new faint round PNe population in the galactic plane

Thank You!

The PNe search; compact PNe Final selection made visually Known PNe in IPHAS two-color diagram IPHAS area; 18 h – 20 h region died tu 810 s α) < , M(H ied ud 13 st 6 ied t stud no 17