Dust-distances to planetary nebulae

Kaler, J. B.; Lutz, J. H.

doi:10.1086/131593

Cited by 51 publications

(58 citation statements)

References 6 publications

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“…their values of N H estimated from the c Hβ logarithmic extinction coefficient determined in Frew (2008) and Frew et al (2013). We used the relationships E B−V = c Hβ (0.61 + 0.024c Hβ ), adopted from Kaler & Lutz (1985), A V = R V E B−V with R V = 3.1, and N H = 1.8 × 10 21 mag −1 cm −2 A V (Bohlin et al 1978) to convert c Hβ to N H . For cases where c Hβ = 0 we have set log N H (cm −2 ) = 19.6.…”

Section: Median Energy As a Proxymentioning

confidence: 99%

THE CHANDRA PLANETARY NEBULA SURVEY (ChanPlaNS). III. X-RAY EMISSION FROM THE CENTRAL STARS OF PLANETARY NEBULAE

Montez

Kastner

Balick

et al. 2015

ApJ

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We present X-ray spectral analysis of 20 point-like X-ray sources detected in Chandra Planetary Nebula Survey observations of 59 planetary nebulae (PNe) in the solar neighborhood. Most of these 20 detections are associated with luminous central stars within relatively young, compact nebulae. The vast majority of these point-like X-rayemitting sources at PN cores display relatively "hard" ( 0.5 keV) X-ray emission components that are unlikely to be due to photospheric emission from the hot central stars (CSPN). Instead, we demonstrate that these sources are well modeled by optically thin thermal plasmas. From the plasma properties, we identify two classes of CSPN X-ray emission: (1) high-temperature plasmas with X-ray luminosities, L X , that appear uncorrelated with the CSPN bolometric luminosity, L bol and (2) lower-temperature plasmas with L X /L bol ∼ 10 −7 . We suggest these two classes correspond to the physical processes of magnetically active binary companions and self-shocking stellar winds, respectively. In many cases this conclusion is supported by corroborative multiwavelength evidence for the wind and binary properties of the PN central stars. By thus honing in on the origins of X-ray emission from PN central stars, we enhance the ability of CSPN X-ray sources to constrain models of PN shaping that invoke wind interactions and binarity.

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Section: Median Energy As a Proxymentioning

confidence: 99%

THE CHANDRA PLANETARY NEBULA SURVEY (ChanPlaNS). III. X-RAY EMISSION FROM THE CENTRAL STARS OF PLANETARY NEBULAE

Montez

Kastner

Balick

et al. 2015

ApJ

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“…Using the observed reddening to the PN (A V = 4.1 ± 0.10), we obtain a distance of D = 5.9 ± 2.2 kpc. The error on the distance is estimated following the approach of Kaler & Lutz (1985), and is probably optimistic as it does not account for any internal reddening in the nebula (if present, D is overestimated). The diamond in Fig.…”

Section: Distancementioning

confidence: 99%

The “Príncipes de Asturias” nebula: a new quadrupolar planetary nebula from the IPHAS survey

Mampaso¹,

Corradi

Viironen³

et al. 2006

A&A

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Context. The Isaac Newton Telescope Photometric Hα Survey (IPHAS) is currently mapping the Northern Galactic plane reaching to r = 20 mag with typically 1 resolution. Hundreds of Planetary Nebulae (PNe), both point-like and resolved, are expected to be discovered. We report on the discovery of the first new PN from this survey: it is an unusual object located at a large galactocentric distance and has a very low oxygen abundance. Aims. Detecting and studying new PNe will lead to improved estimates of the population size, binary fraction and lifetimes, and yield new insights into the chemistry of the interstellar medium at large galactocentric distances. Methods. Compact nebulae are searched for in the IPHAS photometric catalogue, selecting those candidates with a strong Hα excess in the r − Hα vs. r − i colour-colour diagram. Searches for extended nebulae are by visual inspection of the mosaics of continuum-subtracted Hα images at a spatial sampling of 5 × 5 arcsec 2 . Follow-up spectroscopy enables confirmation of the PNe, and their physico-chemical study. Results. The first planetary nebula discovered via IPHAS imagery shows an intricate morphology: there is an inner ring surrounding the central star, bright inner lobes with an enhanced waist, and very faint lobular extensions reaching up to more than 100 . We classify it as a quadrupolar PN, a rather unusual class of planetary showing two pairs of misaligned lobes. From long-slit spectroscopy we derive T e [Nii] = 12 800 ± 1000 K, N e = 390 ± 40 cm IPHAS makes use of the Wide Field Camera (WFC) of the 2.5 m Isaac Newton Telescope (INT) at the Observatorio del Roque de los Muchachos on La Palma, Spain. A narrow-band Hα filter (λ c = 6568 Å; FWHM = 95 Å) and two broad-band Sloan r , i filters are used for matched 120, 30, and 10 s exposures, respectively, spanning the magnitude range 13 ≤ r ≤ 20 for point sources. The survey area is covered in double pass, such that every pointing is repeated at an offset of 5 arcmin in both right ascension and declination. Pipeline data reduction and dataThe object, whose official name is IPHASX J012507.9+635652, is called as "Nebulosa de los Príncipes de Asturias" after its dedication by the Instituto de Astrofísica de Canarias to the Spanish Princes on the occasion of their wedding, which took place in Madrid on May, 22nd, 2004. distribution are handled by the Cambridge Astronomical Survey Unit (CASU http://archive.ast.cam.ac.uk/).IPHAS is the first fully-photometric Hα survey of the Galactic plane, and it will complement the recently completed photographic survey of the southern Galactic plane performed with the AAO UK Schmidt Telescope (Parker et al. 2005) http://www-wfau.roe.ac.uk/sss/halpha/index.html.IPHAS is expected to discover up to 50 000 new emissionline stars, including young stars (T Tau, Herbig AeBe stars, etc.), and evolved ones (post-AGB, LBVs, etc.), as well as different classes of interacting binaries (CVs, symbiotic stars, etc.) in addition to thousands of extended nebulae such as planetary nebu...

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“…In our opinion CKS used the latter: Calibration was based on two sets of extinction distances, Kaler & Lutz (1985) and G86; two examples of cluster membership, Ps 1 and NGC 2818; and two spectroscopic parallaxes, those of NGC 246 and NGC 1514. Expanding shell and gravity distances were explicitly excluded.…”

Section: Calibration Strategies and The 'Short' And 'Long' Statisticamentioning

confidence: 99%

On the distances of planetary nebulae

Smith

2015

Monthly Notices of the Royal Astronomical Society

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Past calibrations of statistical distance scales for planetary nebulae have been problematic, especially with regard to 'short' vs. 'long' scales. Reconsidering the calibration process naturally involves examining the precision and especially the systematic errors of various distance methods. Here we present a different calibration strategy, new for planetaries, that is anchored by precise trigonometric parallaxes for sixteen central stars published by Harris et al. (2007) of USNO, with four improved by Benedict et al. using the Hubble Space Telescope. We show how an internally consistent system of distances might be constructed by testing other methods against those and each other. In such a way systematic errors can be minimized.Several of the older statistical scales have systematic errors that can account for the short-long dichotomy. In addition to scale-factor errors all show signs of radius dependence, i.e. the distance ratio [scale/true] is some function of nebular radius. These systematic errors were introduced by choices of data sets for calibration, by the methodologies used, and by assumptions made about nebular evolution. The statistical scale of Frew and collaborators (2008, 2014) is largely free of these errors, although there may be a radius dependence for the largest objects. One set of spectroscopic parallaxes was found to be consistent with the trigonometric ones while another set underestimates distance consistently by a factor of two, probably because of a calibration difference. 'Gravity' distances seem to be overestimated for nearby objects but may be underestimated for distant objects, i.e. distance-dependent. Angular expansion distances appear to be suitable for calibration after correction for astrophysical effects (e.g. Mellema 2004). We find extinction distances to be often unreliable individually though sometimes approximately correct overall (total sample).Comparison of the Hipparcos parallaxes (van Leeuwen 2007) for large planetaries with our 'best estimate' distances confirms that those parallaxes are overestimated by a factor 2.5, as suggested by Harris et al.'s result for PHL 932. There may be negative implications for Gaia parallaxes for these objects. We suggest a possible connection with the much smaller overestimation recently shown for the Hipparcos Pleiades parallaxes by Melis et al. (2014).

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Dust-distances to planetary nebulae

Cited by 51 publications

References 6 publications

THE CHANDRA PLANETARY NEBULA SURVEY (ChanPlaNS). III. X-RAY EMISSION FROM THE CENTRAL STARS OF PLANETARY NEBULAE

THE CHANDRA PLANETARY NEBULA SURVEY (ChanPlaNS). III. X-RAY EMISSION FROM THE CENTRAL STARS OF PLANETARY NEBULAE

The “Príncipes de Asturias” nebula: a new quadrupolar planetary nebula from the IPHAS survey

On the distances of planetary nebulae

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