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تسجيل مستخدم جديدA new [Oiii] lamda5007 {AA} Galactic Bulge Planetary Nebula Luminosity Function
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The Planetary Nebulae Luminosity Function (PNLF) describes the collective luminosity evolution for a given population of Planetary Nebulae (PN). A major paradox in current PNLF studies is in the universality of the absolute magnitude of the brightest PNe with galaxy type and age. The progenitor central-star mass required to produce such bright PNe should have evolved beyond the PNe phase in old, red elliptical galaxies whose stellar populations are ~10~Gyr. Only by dissecting this resolved population in detail can we attempt to address this conundrum. The Bulge of our Galaxy is predominantly old citep{Z03} and can therefore be used as a proxy for an elliptical galaxy, but with the significant advantage that the population is resolvable from ground based telescopes. We have used the MOSAIC-II camera on the Blanco 4-m at CTIO to carefully target ~80 square degrees of the Galactic Bulge and establish accurate [Oiii] fluxes for 80% of Bulge PNe currently known from the Acker and MASH catalogues. Construction of the [Oiii] Bulge PNLF has allowed us to investigate placement of PNe population sub-sets according to morphology and spectroscopic properties the PNLF and most importantly, whether any population subset might constitute the bright end of the LF. Our excellent, deep data also offers exciting prospects for significant new PNe discoveries and [Oiii] morphological studies.
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Planetary Nebulae (PN) emit enormous amount of energy in several emission lines. Measuring the line-flux for PNe in a given stellar population, the Planetary Nebula Luminosity Function (PNLF) can be compiled. Surveys of PNe revealed that the faint-en
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The planetary nebula luminosity function (PNLF) has been used as an extragalactic distance indicator since the 1980s, but there are still unsolved problems associated with its use. One of the most serious involves PNLF distances beyond ~ 10 Mpc, whic
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