Morphological Properties of the Crab Nebula: A Detailed Multiwavelength Study Based on New VLA, HST, Chandra, and XMM-Newton Images

Dubner, G.; Castelletti, G.; Kargaltsev, Oleg; Pavlov, G. G.; Bietenholz, M. F.; Talavera, A.

doi:10.3847/1538-4357/aa6983

Cited by 23 publications

(20 citation statements)

References 57 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The final column presents the residual after subtracting the model emission from the observed mm wave maps. The residual emission peaks in the centre, and appears to roughly follow the structure of the torus and the jet as seen in X-ray (Seward et al 2006;Madsen et al 2015) and in radio images (Velusamy et al 1992;Bietenholz et al 2015;Dubner et al 2017) of the Crab Nebula (see Fig. 1), which had also been remarked on by Bandiera et al (2002).…”

Section: Spatial Distribution Of Excess Emissionsupporting

confidence: 64%

The dust content of the Crab Nebula

Looze

Barlow

Bandiera

et al. 2019

Monthly Notices of the Royal Astronomical Society

Self Cite

View full text Add to dashboard Cite

We have modelled the near-infrared to radio images of the Crab Nebula with a Bayesian SED model to simultaneously fit its synchrotron, interstellar and supernova dust emission. We infer an interstellar dust extinction map with an average A V = 1.08 ± 0.38 mag, consistent with a small contribution ( 22%) to the Crab's overall infrared emission. The Crab's supernova dust mass is estimated to be between 0.032 and 0.049 M (for amorphous carbon grains) with an average dust temperature T dust =41±3 K, corresponding to a dust condensation efficiency of 8-12%. This revised dust mass is up to an order of magnitude lower than some previous estimates, which can be attributed to our different interstellar dust corrections, lower SPIRE flux densities, and higher dust temperatures than were used in previous studies. The dust within the Crab is predominantly found in dense filaments south of the pulsar, with an average V band dust extinction of A V = 0.20 − 0.39 mag, consistent with recent optical dust extinction studies. The modelled synchrotron power-law spectrum is consistent with a radio spectral index α radio =0.297±0.009 and an infrared spectral index α IR =0.429±0.021. We have identified a millimetre excess emission in the Crab's central regions, and argue that it most likely results from two distinct populations of synchrotron emitting particles. We conclude that the Crab's efficient dust condensation (8-12%) provides further evidence for a scenario where supernovae can provide substantial contributions to the interstellar dust budgets in galaxies.

show abstract

Section: Spatial Distribution Of Excess Emissionsupporting

confidence: 64%

The dust content of the Crab Nebula

Looze

Barlow

Bandiera

et al. 2019

Monthly Notices of the Royal Astronomical Society

Self Cite

View full text Add to dashboard Cite

show abstract

“…Left: VLA radio image of the Crab Nebula at 3GHz(Dubner et al 2017), overlaid with the position and 68% containment radius of FHESJ0534.5+2201 (white × marker and circle). The cyan marker indicates the location of PSRJ0534+2200 as determined from optical/radio measurements.…”

mentioning

confidence: 99%

The Search for Spatial Extension in High-latitude Sources Detected by the Fermi Large Area Telescope

Ackermann¹,

Ajello²,

Baldini³

et al. 2018

ApJS

183

162

View full text Add to dashboard Cite

We present a search for spatial extension in high-latitude (>  | | b 5) sources in recent Fermi point source catalogs. The result is the Fermi High-Latitude Extended Sources Catalog, which provides source extensions (or upper limits thereof) and likelihood profiles for a suite of tested source morphologies. We find 24extended sources, 19 of which were not previously characterized as extended. These include sources that are potentially associated with supernova remnants and star-forming regions. We also found extended γ-ray emission in the vicinity of the CenA radio lobes and-at GeV energies for the first time-spatially coincident with the radio emission of the SNR CTA 1, as well as from the Crab Nebula. We also searched for halos around active galactic nuclei, which are predicted from electromagnetic cascades induced by the e + e − pairs that are deflected in intergalactic magnetic fields. These pairs are produced when γ-rays interact with background radiation fields. We do not find evidence for extension in individual sources or in stacked source samples. This enables us to place limits on the flux of the extended source components, which are then used to constrain the intergalactic magnetic field to be stronger than 3×10 −16 G for a coherence length λ10 kpc, even when conservative assumptions on the source duty cycle are made. This improves previous limits by several orders of magnitude.

show abstract

“…Left: UV (λ = 291 nm) image of the Crab nebula[9]. The MAGIC and HEGRA extension upper limits of 2.2[10] and 1.5[11] are drawn as dash-dotted and dashed lines, respectively.…”

mentioning

confidence: 99%

Advanced search for the extension of unresolved TeV sources with H.E.S.S.

Holler¹,

Berge²,

Hahn³

et al. 2017

Proceedings of 35th International Cosmic Ray Conference — PoS(ICRC2017)

View full text Add to dashboard Cite

The resolution power of current Imaging Atmospheric Cherenkov Telescopes is presently restricted to scales of a few arcminutes. In the very high-energy (VHE; E > 100 GeV) gamma-ray regime, the measurement of source sizes that are comparable to or smaller than the resolution of the instrument is usually limited by statistics and in particular by the uncertainties in the characterisation of the instrument Point Spread Function (PSF). The PSF varies strongly with observation and instrument conditions demanding time dependent simulations of these conditions. Employing such simulations, we substantially improve our understanding of the H.E.S.S. PSF and are now able to probe source extensions well below one arcminute scale. We present the results of this new approach applied to known VHE gamma-ray sources and show how this enables us to reveal for the first time the extension of the Crab nebula at TeV gamma-ray energies, with a width of 52 assuming a Gaussian source shape. * Speaker.

show abstract

Morphological Properties of the Crab Nebula: A Detailed Multiwavelength Study Based on New VLA, HST, Chandra, and XMM-Newton Images

Cited by 23 publications

References 57 publications

The dust content of the Crab Nebula

The dust content of the Crab Nebula

The Search for Spatial Extension in High-latitude Sources Detected by the Fermi Large Area Telescope

Advanced search for the extension of unresolved TeV sources with H.E.S.S.

Contact Info

Product

Resources

About