An official website of the United States government
Abstract Planetary nebula (PN) surveys in systems beyond ∼10 Mpc often find high-excitation, point-like sources with [Oiii]λ5007 fluxes greater than the apparent bright-end cutoff of the planetary nebula luminosity function (PNLF). Here we identify PN superpositions as one likely cause for the phenomenon and describe the proper procedures for deriving PNLF distances when object blends are a possibility. We apply our technique to two objects: a model Virgo-distance elliptical galaxy observed through a narrowband interference filter, and the Fornax lenticular galaxy NGC 1380 surveyed with the MUSE integral-field unit spectrograph. Our analyses show that even when the most likely distance to a galaxy is unaffected by the possible presence of PN superpositions, the resultant value will still be biased toward too small a distance due to the asymmetrical nature of the error bars. We discuss the future of the PNLF in an era where current ground-based instrumentation can push the technique to distances beyond ∼35 Mpc.
more »
« less
The Planetary Nebula Luminosity Function in the Era of Precision Cosmology
One of the great surprises of the late 1980s was the discovery that the [O III] λ 5007 planetary nebula luminosity function (PNLF) could be used as a precision extragalactic standard candle. Despite the lack of any robust theory for the phenomenon, the technique passed a myriad of internal and external tests, and became an extremely reliable tool for obtaining distances to large galaxies within ∼ 20 Mpc. But in more recent years, the use of the technique has declined, due in part to the changing landscape of cosmology. Here we review the history of the PNLF, the experiments that confirmed its utility, and the reasons why interest in the method faded at the turn of the millennium. We also describe how and why the PNLF is making a comeback, and present some of the method’s recent results. Finally, we discuss how the PNLF must be analyzed in the era of precision cosmology, and detail the issues that must be overcome in order to address the current tension between local measures of the Hubble constant and values derived from the microwave background. If these issues can be understood, then the PNLF can provide a useful cross-check on distance measurements out to ∼ 40 Mpc.
more »
« less
- Award ID(s):
- 2206090
- PAR ID:
- 10428498
- Date Published:
- Journal Name:
- Frontiers in Astronomy and Space Sciences
- Volume:
- 9
- ISSN:
- 2296-987X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
Aims.We perform a deep survey of planetary nebulae (PNe) in the spiral galaxy NGC 300 to construct its planetary nebula luminosity function (PNLF). We aim to derive the distance using the PNLF and to probe the characteristics of the most luminous PNe. Methods.We analysed 44 fields observed with MUSE at the VLT, covering a total area of ∼11 kpc2. We find [O III]λ5007 sources using the differential emission line filter (DELF) technique. We identified PNe through spectral classification with the aid of the BPT diagram. The PNLF distance was derived using the maximum likelihood estimation technique. For the more luminous PNe, we also measured their extinction using the Balmer decrement. We estimated the luminosity and effective temperature of the central stars of the luminous PNe based on estimates of the excitation class and the assumption of optically thick nebulae. Results.We identify 107 PNe and derive a most-likely distance modulus $$ (m-M)_0 = 26.48^{+0.11}_{-0.26} $$ ($$ d = 1.98^{+0.10}_{-0.23} $$ Mpc). We find that the PNe at the PNLF cutoff exhibit relatively low extinction, with some high-extinction cases caused by local dust lanes. We present the lower limit luminosities and effective temperatures of the central stars for some of the brighter PNe. We also identify a few Type I PNe that come from a young population with progenitor masses > 2.5 M⊙but do not populate the PNLF cutoff. Conclusions.The spatial resolution and spectral information of MUSE allow precise PN classification and photometry. These capabilities also enable us to resolve possible contamination by diffuse gas and dust, improving the accuracy of the PNLF distance to NGC 300.more » « less
-
Abstract Thanks to the MUSE integral field spectrograph on board the Very Large Telescope (VLT), extragalactic distance measurements with the [Oiii]λ5007 planetary nebula luminosity function (PNLF) are now possible out to ∼40 Mpc. Here we analyze the VLT/MUSE data for 20 galaxies from the ESO public archive to identify the systems’ planetary nebulae (PNe) and determine their PNLF distances. Three of the galaxies do not contain enough PNe for a robust measure of the PNLF, and the results for one other system are compromised of the galaxy’s internal extinction. However, we obtain robust PNLF distances for the remaining 16 galaxies, two of which are isolated and beyond 30 Mpc in a relatively unperturbed Hubble flow. From these data, we derive a Hubble constant of 74.2 ± 7.2 (stat) ±3.7 (sys) km s−1Mpc−1, a value that is very similar to that found from other quality indicators (e.g., Cepheids, the tip of the red giant branch, and surface brightness fluctuations). At present, the uncertainty is dominated by the small number of suitable galaxies in the ESO archive and their less-than-ideal observing conditions and calibrations. Based on our experience with these systems, we identify the observational requirements necessary for the PNLF to yield a competitive value forH0that is independent of the Type Ia supernova distance scale.more » « less
-
ABSTRACT Feedback from active galactic nuclei and stellar processes changes the matter distribution on small scales, leading to significant systematic uncertainty in weak lensing constraints on cosmology. We investigate how the observable properties of group-scale haloes can constrain feedback’s impact on the matter distribution using Cosmology and Astrophysics with MachinE Learning Simulations (CAMELS). Extending the results of previous work to smaller halo masses and higher wavenumber, k, we find that the baryon fraction in haloes contains significant information about the impact of feedback on the matter power spectrum. We explore how the thermal Sunyaev Zel’dovich (tSZ) signal from group-scale haloes contains similar information. Using recent Dark Energy Survey weak lensing and Atacama Cosmology Telescope tSZ cross-correlation measurements and models trained on CAMELS, we obtain 10 per cent constraints on feedback effects on the power spectrum at $$k \sim 5\, h\, {\rm Mpc}^{-1}$$. We show that with future surveys, it will be possible to constrain baryonic effects on the power spectrum to $$\mathcal {O}(\lt 1~{{\ \rm per\ cent}})$$ at $$k = 1\, h\, {\rm Mpc}^{-1}$$ and $$\mathcal {O}(3~{{\ \rm per\ cent}})$$ at $$k = 5\, h\, {\rm Mpc}^{-1}$$ using the methods that we introduce here. Finally, we investigate the impact of feedback on the matter bispectrum, finding that tSZ observables are highly informative in this case.more » « less
-
null (Ed.)ABSTRACT In 21-cm cosmology, precision calibration is key to the separation of the neutral hydrogen signal from very bright but spectrally smooth astrophysical foregrounds. The Hydrogen Epoch of Reionization Array (HERA), an interferometer specialized for 21-cm cosmology and now under construction in South Africa, was designed to be largely calibrated using the self-consistency of repeated measurements of the same interferometric modes. This technique, known as redundant-baseline calibration resolves most of the internal degrees of freedom in the calibration problem. It assumes, however, on antenna elements with identical primary beams placed precisely on a redundant grid. In this work, we review the detailed implementation of the algorithms enabling redundant-baseline calibration and report results with HERA data. We quantify the effects of real-world non-redundancy and how they compare to the idealized scenario in which redundant measurements differ only in their noise realizations. Finally, we study how non-redundancy can produce spurious temporal structure in our calibration solutions – both in data and in simulations – and present strategies for mitigating that structure.more » « less
- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3389/fspas.2022.896326
