The Chandra Planetary Nebulae Survey (ChanPlaNS): III. X-ray Emission from the Central Stars of Planetary Nebulae

Abstract

We present X-ray spectral analysis of 20 point-like X-ray sources detected in Chandra Planetary Nebula Survey (ChanPlaNS) 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-ray-emitting sources at PN cores display relatively "hard" ($\ge 0.5$~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, $L_{\mathrm{X}}$, that appear uncorrelated with the CSPN bolometric luminosity, $L_{\mathrm{bol}}$; and (2) lower-temperature plasmas with $L_{\mathrm{X}}/L_{\mathrm{bol}}\sim 10^{-7}$. 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.

A-c-c-e-p-t-e-d by ApJ; ChanPlaNS website: http://lama.cis.rit.edu/chanplans/; remember to tip your servers!

References in corpus (5)

• A Debris Disk around the Central Star of the Helix Nebula?
• The Chandra Planetary Nebula Survey (ChanPlaNS). II. X-ray Emission from Compact Planetary Nebulae
• The Discovery of Infrared Rings in the Planetary Nebula NGC 1514 During the WISE All-Sky Survey
• Very Late Thermal Pulses Influenced by Accretion in Planetary Nebulae
• Rummaging inside the Eskimo's parka: Variable asymmetric PN fast wind and a binary nucleus?

Cited by in corpus (18)

• The gas-to-extinction ratio and the gas distribution in the Galaxy
• Planetary Nebulae: Sources of Enlightenment
• Catalogue of central stars of planetary nebulae: Expanded edition
• Formation and X-ray Emission from Hot Bubbles in Planetary Nebulae. II. Hot bubble X-ray emission
• A New Radio Molecular Line Survey of Planetary Nebulae: HNC/HCN as a Diagnostic of Ultraviolet Irradiation
• The Herschel Planetary Nebula Survey (HerPlaNS) - a comprehensive dusty photoionization model of NGC6781
• Forming H-shaped and barrel-shaped nebulae with interacting jets
• The post-common-envelope X-ray binary nucleus of the planetary nebula NGC 2392
• Planetary nebulae with Wolf-Rayet-type central stars -- I. The case of the high-excitation NGC 2371
• Sampling Molecular Gas in the Helix Planetary Nebula: Variation in HNC/HCN with UV Flux
• Chandra observations of the planetary nebula IC 4593
• A carbon-rich hot bubble in the planetary nebula NGC 5189
• Variable jets at the termination of the common envelope evolution
• Planetary nebulae hosting accreting white dwarfs: A possible solution for the mysterious cut-off of Planetary Nebula Luminosity Function?
• Evidence for the disruption of a planetary system during the formation of the Helix Nebula
• The rare extended radio-loud narrow-line Seyfert 1 galaxy SDSS J1030+5516 at high resolution
• A catalogue of 108 extended planetary nebulae observed by GALEX
• Planetary Nebulae in the eROSITA eRASS1 catalog