Planetary nebulae as standard candles. X. Tests in the Coma I region. J/ApJ/462/1 J/ApJ/462/1 PNe in the Coma I region Planetary nebulae as standard candles. X. Tests in the Coma I region. G H Jacoby R Ciardullo W E Harris Astrophys. J. 462 1 1996 1996ApJ...462....1J Nebulae, planetary distance scale galaxies: clusters: individual (Coma I) We present the result of an [OIII]500.7nm survey for planetary nebulae (PNe) in three galaxies of the Coma I group: NGC 4278 (Hubble type E1), NGC 4494 (E1), and NGC 4565 (edge-on Sb). Using the planetary nebula luminosity function (PNLF), we derived distances to NGC 4494 (12.8+/-0.9Mpc), NGC 4564 (10.5^+0.8^_-1.0_Mpc), and NGC 4278 (10.2^+0.7^_-1.0_Mpc). The larger distance for NGC 4494 is significant beyond the 99% confidence level when the common systematic errors in all three distances are removed. This agrees with the results of the globular cluster luminosity function and surface brightness fluctuation methods, both of which place NGC 4565 in front of NGC 4494. The large separation is also consistent with the results of Virgocentric flow models, which predict triple-valued solutions to the Hubble flow in that direction.
NGC 4278 planetary nebulae NGC 4494 planetary nebulae ID ID number --- RAh Right ascension (J2000) h RAm Right ascension (J2000) min RAs Right ascension (J2000) s DEd Declination (J2000) deg DEm Declination (J2000) arcmin DEs Declination (J2000) arcsec Rad Isophotal radius from galaxy arcmin m5007 Lambda5007 magnitude (m5007=-2.5logF5007 - 13.74) mag Note Note number=1 S when PNe that are part of the statistical samples --- NGC 4565 planetary nebulae ID ID number --- RAh Right ascension (J2000) h RAm Right ascension (J2000) min RAs Right ascension (J2000) s DEd Declination (J2000) deg DEm Declination (J2000) arcmin DEs Declination (J2000) arcsec z PN distance from galactic plane arcsec m5007 Lambda5007 magnitude (m5007=-2.5logF5007 - 13.74) mag Note S when PNe that are part of the statistical samples --- Astrometric reference stars Name Galaxy name --- ID Star identification --- RAh Right ascension (J2000) h RAm Right ascension (J2000) min RAs Right ascension (J2000) s DEd Declination (J2000) deg DEm Declination (J2000) arcmin DEs Declination (J2000) arcsec Patricia Bauer CDS 1996Sep06Robin Ciardullo <rbc@astro.psu.edu> J_ApJ_462_1.xml