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Dust destruction by supernovae is one of the main processes removing dust from the interstellar medium (ISM). Estimates of the efficiency of this process, both theoretical and observational, typically assume a shock propagating into a homogeneous medium, whereas the ISM possesses significant substructure in reality. We self-consistently model the dust and gas properties of the shocked ISM in three supernova remnants (SNRs), using X-ray and infrared (IR) data combined with corresponding emission models. Collisional heating by gas with properties derived from X-ray observations produces dust temperatures too high to fit the far-IR fluxes from each SNR. An additional colder dust component is required, which has a minimum mass several orders of magnitude larger than that of the warm dust heated by the X-ray emitting gas. Dust-to-gas mass ratios indicate that the majority of the dust in the X-ray emitting material has been destroyed, while the fraction of surviving dust in the cold component is plausibly close to unity. As the cold component makes up virtually all the total dust mass, destruction time-scales based on homogeneous models, which cannot account for multiple phases of shocked gas and dust, may be significantly overestimating actual dust destruction efficiencies, and subsequently underestimating grain lifetimes. [ABSTRACT FROM AUTHOR]

We search for far-infrared (FIR) counterparts of known supernova remnants (SNRs) in the Galactic plane (360° in longitude and |$b = \pm \, 1^{\circ }$|⁠) at 70–500  μ m with Herschel. We detect dust signatures in 39 SNRs out of 190, made up of 13 core-collapse supernovae (CCSNe), including 4 Pulsar Wind Nebulae (PWNe), and 2 Type Ia SNe. A further 24 FIR detected SNRs have unknown types. We confirm the FIR detection of ejecta dust within G350.1−0.3, adding to the known sample of ∼ 10 SNRs containing ejecta dust. We discover dust features at the location of a radio core at the centre of G351.2+0.1, indicating FIR emission coincident with a possible Crab-like compact object, with dust temperature and mass of Td  = 45.8 K and Md  = 0.18 M⊙, similar to the PWN G54.1+0.3. We show that the detection rate is higher among young SNRs. We produce dust temperature maps of 11 SNRs and mass maps of those with distance estimates, finding dust at temperatures |$15\, \lesssim \, T_d\, \lesssim \, 40$|  K. If the dust is heated by shock interactions the shocked gas must be relatively cool and/or have a low density to explain the observed low grain temperatures. [ABSTRACT FROM AUTHOR]

We search for far-infrared counterparts of known supernova remnants (SNRs) in the Galactic plane (10° < | l | < 60°) at 70–500 μm using the Herschel Infrared Galactic Plane Survey (Hi-GAL). Of 71 sources studied, we find that 29 (41   per cent) SNRs have a clear FIR detection of dust emission associated with the SNR. Dust from 8 of these is in the central region, and 4 indicate pulsar wind nebulae (PWNe) heated ejecta dust. A further 23 have dust emission in the outer shell structures which is potentially related to swept-up material. Many Galactic SNe have dust signatures but we are biased towards detecting ejecta dust in young remnants and those with a heating source (shock or PWN). We estimate the dust temperature and mass contained within three PWNe, G11.2–0.3, G21.5–0.9, and G29.7–0.3, using modified blackbody fits. To more rigorously analyse the dust properties at various temperatures and dust emissivity index β, we use point process mapping (PPMAP). We find significant quantities of cool dust (at 20–40 K) with dust masses of M d  =  0.34 ± 0.14 M⊙, M d  =  0.29 ± 0.08 M⊙, and M d  =  0.51 ± 0.13 M⊙ for G11.2–0.3, G21.5–0.9, and G29.7–0.3, respectively. We derive the dust emissivity index for the PWN ejecta dust in G21.5–0.3 to be |$\beta \, =\, 1.4 \pm 0.5$| compared to dust in the surrounding medium where |$\beta \, =\, 1.8 \pm 0.1$|⁠. [ABSTRACT FROM AUTHOR]

Shockwaves driven by supernovae both destroy dust and reprocess the surviving grains, greatly affecting the resulting dust properties of the interstellar medium (ISM). While these processes have been extensively studied theoretically, observational constraints are limited. We use physically motivated models of dust emission to fit the infrared (IR) spectral energy distributions of seven Galactic supernova remnants, allowing us to determine the distribution of dust mass between diffuse and dense gas phases, and between large and small grain sizes. We find that the dense (⁠|$\sim \! 10^3\ {\rm cm}^{-3}$|⁠), relatively cool (⁠|$\sim \! 10^3\ {\rm K}$|⁠) gas phase contains |$\gt 90{{\ \rm per\ cent}}$| of the dust mass, making the warm dust located in the X-ray emitting plasma (⁠|$\sim \! 1\ {\rm cm}^{-3}$| / |$10^6\ {\rm K}$|⁠) a negligible fraction of the total, despite dominating the mid-IR emission. The ratio of small (⁠|$\lesssim\!{10}\ {\rm nm}$|⁠) to large (⁠|$\gtrsim \! 0.1\ {\rm \mu m}$|⁠) grains in the cold component is consistent with that in the ISM, and possibly even higher, whereas the hot phase is almost entirely devoid of small grains. This suggests that grain shattering, which processes large grains into smaller ones, is ineffective in the low-density gas, contrary to model predictions. Single-phase models of dust destruction in the ISM, which do not account for the existence of the cold swept-up material containing most of the dust mass, are likely to greatly overestimate the rate of dust destruction by supernovae. [ABSTRACT FROM AUTHOR]

Modelling the red–blue asymmetries seen in the broad emission lines of core-collapse supernovae (CCSNe) is a powerful technique to quantify total dust mass formed in the ejecta at late times (>5 yr after outburst) when ejecta dust temperatures become too low to be detected by mid-infrared (IR) instruments. Following our success in using the Monte Carlo radiative transfer code damocles to measure the dust mass evolution in SN 1987A and other CCSNe, we present the most comprehensive sample of dust mass measurements yet made with damocles , for CCSNe aged between 4 and 60 yr after outburst. Our sample comprises multi-epoch late-time optical spectra taken with the Gemini/Gemini Multi-Object Spectrographs (GMOS) and Very Large Telescope (VLT) X-Shooter spectrographs, supplemented by archival spectra. For the 14 CCSNe that we have modelled, we confirm a dust mass growth with time that can be fit by a sigmoid curve that is found to saturate beyond an age of ∼30 yr, at a mass of 0.23 |$^{+0.17}_{-0.12}$|  M⊙. For an expanded sample including dust masses found in the literature for a further 11 CCSNe and six CCSN remnants, the dust mass at saturation is found to be 0.42 |$^{+0.09}_{-0.05}$|  M⊙. Uncertainty limits for our dust masses were determined from a Bayesian analysis using the affine invariant Markov chain Monte Carlo ensemble sampler emcee with damocles. The best-fitting line profile models for our sample all required grain radii between 0.1 and 0.5  |$\mu$| m. Our results are consistent with CCSNe forming enough dust in their ejecta to significantly contribute to the dust budget of the Universe. [ABSTRACT FROM AUTHOR]

The discovery with the Herschel Space Observatory of bright far-infrared and submm emission from the ejecta of the core-collapse supernova SN 1987A has been interpreted as indicating the presence of some 0.4-0.7 M☉ of dust. We have constructed radiative transfer models of the ejecta to fit optical to far-infrared observations from the literature at epochs between 615 d and 24 years after the explosion, to determine when and where this unexpectedly large amount of dust formed. We find that the observations by day 1153 are consistent with the presence of 3 × 10-3 M☉ of dust. Although this is a larger amount than has previously been considered possible at this epoch, it is still very small compared to the amount present in the remnant after 24 years, and significantly higher dust masses at the earlier epochs are firmly ruled out by the observations, indicating that the majority of the dust must have formed at very late times. By 8515-9200 d after the explosion, 0.6-0.8M☉ of dust is present, and dust grains with radii greater than 2 μm are required to obtain a fit to the observed spectral energy distribution (SED). This suggests that the dust mass increase at late times was caused by accretion on to and coagulation of the dust grains formed at earlier epochs. These findings provide further confirmation that core-collapse supernovae can create large quantities of dust, and indicate that the reason for small dust masses being estimated in many cases is that the vast majority of the dust forms long after most supernovae have been detectable at mid-infrared wavelengths. [ABSTRACT FROM AUTHOR]

We present complicated dust structures within multiple regions of the candidate supernova remnant (SNR) the 'Tornado' (G357.7–0.1) using observations with Spitzer and Herschel. We use point process mapping, ppmap , to investigate the distribution of dust in the Tornado at a resolution of 8 arcsec, compared to the native telescope beams of 5–36 arcsec. We find complex dust structures at multiple temperatures within both the head and the tail of the Tornado, ranging from 15 to 60 K. Cool dust in the head forms a shell, with some overlap with the radio emission, which envelopes warm dust at the X-ray peak. Akin to the terrestrial sandy whirlwinds known as 'dust devils', we find a large mass of dust contained within the Tornado. We derive a total dust mass for the Tornado head of 16.7  |$\rm M_{\odot }$|⁠ , assuming a dust absorption coefficient of κ300 = 0.56  |$\rm m^2\, kg^{-1}$|⁠ , which can be explained by interstellar material swept up by a SNR expanding in a dense region. The X-ray, infrared, and radio emission from the Tornado head indicate that this is a SNR. The origin of the tail is more unclear, although we propose that there is an X-ray binary embedded in the SNR, the outflow from which drives into the SNR shell. This interaction forms the helical tail structure in a similar manner to that of the SNR W50 and microquasar SS 433. [ABSTRACT FROM AUTHOR]

We present observations of the pulsar-wind nebula (PWN) region of SNR 0540-69.3. The observations were made with the Atacama Compact Array (ACA) in Bands 4 and 6. We also add radio observations from the Australia Compact Array at 3 cm. For 1.449–233.50 GHz, we obtain a synchrotron spectrum |$F_{\nu } \propto \nu ^{-\alpha _{\nu }}$|⁠ , with the spectral index αν = 0.17 ± 0.02. To conclude how this joins the synchrotron spectrum at higher frequencies, we include hitherto unpublished AKARI mid-infrared data, and evaluate published data in the ultraviolet (UV), optical, and infrared (IR). In particular, some broad-band filter data in the optical must be discarded from our analysis due to contamination by spectral line emission. For the UV/IR part of the synchrotron spectrum, we arrive at |$\alpha _{\nu } = 0.87^{+0.08}_{-0.10}$|⁠. There is room for 2.5 × 10−3 M⊙ of dust with a temperature of ∼55 K if there are dual breaks in the synchrotron spectrum, one around ∼9 × 1010 Hz and another at ∼2 × 1013 Hz. The spectral index then changes at ∼9 × 1010 Hz from αν = 0.14 ± 0.07 in the radio to |$\alpha _{\nu } = 0.35^{-0.07}_{+0.05}$| in the millimetre-to-far-IR range. The ACA Band 6 data marginally resolve the PWN. In particular, the strong emission |$\text{$\sim$} 1\hbox{$.\!\!^{\prime \prime }$}5$| south-west of the pulsar, seen at other wavelengths, and resolved in the 3 cm data with its 0.″8 spatial resolution, is also strong in the millimetre range. The ACA data clearly reveal the supernova remnant shell ∼20–35 arcsec west of the pulsar, and for the shell we derive αν = 0.64 ± 0.05 for the range 8.6–145 GHz. [ABSTRACT FROM AUTHOR]

We have modelled the near-infrared to radio images of the Crab Nebula with a Bayesian SED model to simultaneously fit its synchrotron, interstellar (IS), and supernova dust emission. We infer an IS dust extinction map with an average A V = 1.08 ± 0.38 mag, consistent with a small contribution (⁠|${\lesssim }22{{\ \rm per\ cent}}$|⁠) 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  |${{\ \rm per\ cent}}$|⁠. This revised dust mass is up to an order of magnitude lower than some previous estimates, which can be attributed to our different IS 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 αradio = 0.297 ± 0.009 and an infrared spectral index αIR = 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  |${{\ \rm per\ cent}}$|⁠) provides further evidence for a scenario where supernovae can provide substantial contributions to the IS dust budgets in galaxies. [ABSTRACT FROM AUTHOR]

In order to understand the contribution of core-collapse supernovae to the dust budget of the early Universe, it is important to understand not only the mass of dust that can form in core-collapse supernovae but also the location and rate of dust formation. SN 2005ip is of particular interest since dust has been inferred to have formed in both the ejecta and the post-shock region behind the radiative reverse shock. We have collated eight optical archival spectra that span the lifetime of SN 2005ip and we additionally present a new X-shooter optical–near-IR spectrum of SN 2005ip at 4075 d post-discovery. Using the Monte Carlo line transfer code damocles, we have modelled the blueshifted broad and intermediate-width H α, H β, and He  i lines from 48 to 4075 d post-discovery using an ejecta dust model. We find that dust in the ejecta can account for the asymmetries observed in the broad and intermediate-width H α, H β, and He  i line profiles at all epochs and that it is not necessary to invoke post-shock dust formation to explain the blueshifting observed in the intermediate-width post-shock lines. Using a Bayesian approach, we have determined the evolution of the ejecta dust mass in SN 2005ip over 10 yr presuming an ejecta dust model, with an increasing dust mass from ∼10−8 M⊙ at 48 d to a current dust mass of ∼0.1 M⊙. [ABSTRACT FROM AUTHOR]

Theoretical models predict that core-collapse supernovae (CCSNe) can be efficient dust producers (0.1-1.0 M☉), potentially accounting for most of the dust production in the early Universe. Observational evidence for this dust production efficiency is however currently limited to only a few CCSN remnants (e.g. SN 1987A, Crab nebula). In this paper, we revisit the dust mass produced in Cassiopeia A (Cas A), a ~330-yr old O-rich Galactic supernova remnant (SNR) embedded in a dense interstellar foreground and background. We present the first spatially resolved analysis of Cas A based on Spitzer and Herschel infrared and submillimetre data at a common resolution of ~0.6 arcmin for this 5 arcmin diameter remnant following a careful removal of contaminating line emission and synchrotron radiation. We fit the dust continuum from 17 to 500 μm with a four-component interstellar medium and supernova (SN) dust model.We find a concentration of cold dust in the unshocked ejecta of Cas A and derive a mass of 0.3-0.5M☉ of silicate grains freshly produced in the SNR, with a lower limit of ≥0.1- 0.2 M☉. For a mixture of 50 per cent of silicate-type grains and 50 per cent of carbonaceous grains, we derive a total SN dust mass between 0.4 and 0.6M☉. These dust mass estimates are higher than from most previous studies of Cas A and support the scenario of SN-dominated dust production at high redshifts. We furthermore derive an interstellar extinction map for the field around Cas A which towards Cas A gives average values of AV = 6-8 mag, up to a maximum of AV = 15 mag. [ABSTRACT FROM AUTHOR]