Narrowband Imaging in [O III] and Hα to Search for Intracluster Planetary Nebulae in the Virgo Cluster

摘要: We have identified intracluster planetary nebulae (PNs) in a Virgo Cluster core field by imaging with the Subaru Suprime-Cam through two narrowband filters centered at redshifted wavelengths of [O III] λ5007 and Hα 6563 A lines; broadband images V R were acquired to check for emission adjacent continuum. Emission-line objects are then selected from two-color diagram III]-Hα versus III]-(V+R), which is calibrated using PNs M84 (Jacoby et al.). Using both allows us distinguish bona fide high-redshift emission-line galaxies bright end luminosity function. Spectroscopic observations subsample these made Telescopio Nazionale Galileo Very Large Telescope region around an field, respectively. The confirm efficiency combined III]+Hα identify true PNs. also obtained first spectrum PN that shows doublet signal-to-noise ratio greater than 10 its emission. From results based on spectroscopic follow-up, we derive lower limit fraction light contributed stars surveyed position cluster core: it amounts 10%.