The environment of supernova remnant VRO 42.05.01 as probed with IRAM 30m molecular line observations

Context. The environment of supernova remnants (SNRs) is a key factor in their evolution, particularly at later stages of their existence. Mixed-morphology (MM) SNRs have a peculiar centre-filled X-ray shape that remains enigmatic. It is often assumed that they evolve in very dense environments, and that the X-ray morphology is due to interactions between the SNRs and their surroundings. Aims. We aim to determine whether VRO 42.05.01 is embedded in, and interacting with, a dense molecular environment. We also aim to understand the multi-wavelength emission from the environment of this SNR, and whether the interstellar material can be responsible for the the MM nature of the source, and for its strange radio and optical shape. Methods. We used the IRAM telescope in Pico Veleta, Spain, to search for signs of interaction between the SNR and neighbouring molecular clouds. We observed a region of 26′ × 14′ towards the west of VRO 42.05.01 and a region of 8′ × 4′ towards the north of the remnant in the 12CO J = 1−0, 13CO J = 1−0, and 12CO J = 2−1 transitions with the EMIR receiver. We made maps of the properties of the observed molecular clouds (peak temperatures, central velocities, velocity dispersions), as well as maps of column density along the line of sight, and ratio of the 12CO J = 2−1 to 12CO J = 1−0 transitions. We also analyse archival optical, infrared, and radio spectroscopic data for other hints on the nature of the medium. Results. We do not find conclusive physical proof that the SNR is interacting with the few, clumpy molecular clouds that surround it in the region of our observations, although there is some suggestion of such interaction (in a region outside our map) from infrared emission. We find that there is a velocity gradient in one of the molecular clouds that is consistent with a stellar wind blown by a 12−14 M⊙ progenitor star. We reassess the literature distance to VRO 42.05.01, and propose that it has a local standard of rest velocity of − 6 km s−1, and that it is located 1.0 ± 0.4 kpc away (the earlier distance value was 4.5 ± 1.5 kpc). We find that a dust sheet intersects VRO 42.05.01 and is possibly related to its double shell-shaped morphology.

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Infrared Analysis of Supernova Remnants

International Astronomical Union Colloquium ◽

10.1017/s0252921100102672 ◽

1988 ◽

Vol 101 ◽

pp. 363-378 ◽

Cited By ~ 1

Author(s):

Eli Dwek

Keyword(s):

Supernova Remnants ◽

Infrared Emission ◽

Infrared Analysis ◽

Atomic Processes ◽

Infrared Observations ◽

X Ray ◽

Physical Conditions ◽

The Galaxy ◽

Dust Grain ◽

Astronomical Satellite

AbstractInfrared observations of supernova remnants obtained with the Infrared Astronomical Satellite provide new insights into the dynamics and energetics of the remnants, and into their interaction with the ambient interstellar medium. In most remnants the infrared emission arises from dust that is collisionally heated by the X-ray emitting gas. The infrared observations can therefore be used as a diagnostic for the physical conditions of the shocked gas. In particular, it is shown that all the prominent X-ray remnants in the Galaxy and in the LMC cool mainly by dust grain collisions instead of atomic processes.

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Interaction between molecular clouds and MeV–TeV cosmic-ray protons escaped from supernova remnants

Publications of the Astronomical Society of Japan ◽

10.1093/pasj/psz058 ◽

2019 ◽

Vol 71 (4) ◽

Cited By ~ 2

Author(s):

Ken Makino ◽

Yutaka Fujita ◽

Kumiko K Nobukawa ◽

Hironori Matsumoto ◽

Yutaka Ohira

Keyword(s):

Gamma Rays ◽

Molecular Clouds ◽

Supernova Remnants ◽

Gamma Ray ◽

Cosmic Ray ◽

Iron Line ◽

X Ray ◽

Line Intensities ◽

Neutral Gas ◽

Additional Support

Abstract Recent discovery of the X-ray neutral iron line (Fe i Kα at 6.40 keV) around several supernova remnants (SNRs) show that MeV cosmic-ray (CR) protons are distributed around the SNRs and are interacting with neutral gas there. We propose that these MeV CRs are the ones that have been accelerated at the SNRs together with GeV–TeV CRs. In our analytical model, the MeV CRs are still confined in the SNR when the SNR collides with molecular clouds. After the collision, the MeV CRs leak into the clouds and produce the neutral iron line emissions. On the other hand, GeV–TeV CRs had already escaped from the SNRs and emitted gamma-rays through interaction with molecular clouds surrounding the SNRs. We apply this model to the SNRs W 28 and W 44 and show that it can reproduce the observations of the iron line intensities and the gamma-ray spectra. This could be additional support of the hadronic scenario for the gamma-ray emissions from these SNRs.

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Modeling the mixed-morphology supernova remnant IC 443

Astronomy and Astrophysics ◽

10.1051/0004-6361/202039940 ◽

2021 ◽

Vol 649 ◽

pp. A14 ◽

Cited By ~ 1

Author(s):

S. Ustamujic ◽

S. Orlando ◽

E. Greco ◽

M. Miceli ◽

F. Bocchino ◽

...

Keyword(s):

Blast Wave ◽

Parameter Space ◽

Supernova Remnants ◽

Ambient Medium ◽

Complex Structure ◽

Main Property ◽

Asymmetric Distribution ◽

Complex Environment ◽

X Ray ◽

Multi Wavelength

Context. The morphology and the distribution of material observed in supernova remnants (SNRs) reflect the interaction of the supernova (SN) blast wave with the ambient environment, the physical processes associated with the SN explosion, and the internal structure of the progenitor star. IC 443 is a mixed-morphology (MM) SNR located in a quite complex environment: it interacts with a molecular cloud in the northwestern and southeastern areas and with an atomic cloud in the northeast. Aims. In this work, we aim to investigate the origin of the complex morphology and multi-thermal X-ray emission observed in SNR IC 443 through the study of the effect of the inhomogeneous ambient medium in shaping its observed structure and an exploration of the main parameters characterizing the remnant. Methods. We developed a 3D hydrodynamic (HD) model for IC 443, which describes the interaction of the SNR with the environment, parametrized in agreement with the results of the multi-wavelength data analysis. We performed an ample exploration of the parameter space describing the initial blast wave and the environment, including the mass of the ejecta, the energy and position of the explosion, as well as the density, structure, and geometry of the surrounding clouds. From the simulations, we synthesized the X-ray emission maps and spectra and compared them with actual X-ray data collected by XMM-Newton. Results. Our model explains the origin of the complex X-ray morphology of SNR IC 443 in a natural way, with the ability to reproduce, for the first time, most of the observed features, including the centrally-peaked X-ray morphology (characteristic of MM SNRs) when considering the origin of the explosion at the position where the pulsar wind nebula CXOU J061705.3+222127 was at the time of the explosion. In the model that best reproduces the observations, the mass of the ejecta and the energy of the explosion are ~7 M⊙ and ~1 × 1051 erg, respectively. From the exploration of the parameter space, we find that the density of the clouds is n > 300 cm−3 and that the age of SNR IC 443 is ~8000 yr. Conclusions. The observed inhomogeneous ambient medium is the main property responsible for the complex structure and the X-ray morphology of SNR IC 443, resulting in a very asymmetric distribution of the ejecta due to the off-centered location of the explosion inside the cavity formed by the clouds. It can be argued that the centrally peaked morphology (typical of MM SNRs) is a natural consequence of the interaction with the complex environment. A combination of high resolution X-ray observations and accurate 3D HD modeling is needed to confirm whether this scenario is applicable to other MM SNRs.

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Exceptionally bright optical emission from a rare and distant gamma-ray burst

10.21203/rs.3.rs-1101440/v1 ◽

2021 ◽

Author(s):

Gor Oganesyan ◽

Sergey Karpov ◽

Martin Jelinek ◽

Gregory Beskin ◽

Samuele Ronchini ◽

...

Keyword(s):

Gamma Ray ◽

Massive Stars ◽

Optical Emission ◽

Gamma Ray Bursts ◽

Additional Component ◽

Relativistic Jets ◽

X Ray ◽

Forward Shock ◽

Multi Wavelength ◽

Wavelength Emission

Abstract Long gamma-ray bursts (GRBs) are produced by the dissipation of ultra-relativistic jets launched by newly-born black holes after the collapse of massive stars. Right after the luminous and highly variable gamma-ray emission, the multi-wavelength afterglow is released by the external dissipation of the jet in circumburst medium. We report the discovery of a very bright (10 mag) optical emission 28 s after the explosion of the extremely luminous and energetic GRB 210619B located at redshift 1.937. Early multi-filter observations allowed us to witness the end of the shock wave propagation into the GRB ejecta. We observed the spectral transition from a bright reverse to the forward shock emission, demonstrating that the early and late GRB multi-wavelength emission is originated from a very narrow jet propagating into an unusually rarefied interstellar medium. We also find evidence of an additional component of radiation, coming from the jet wings which is able explain the uncorrelated optical/X-ray emission.

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Measuring the distance to the black hole candidate X-ray binary MAXI J1348–630 using H i absorption

Monthly Notices of the Royal Astronomical Society Letters ◽

10.1093/mnrasl/slaa195 ◽

2020 ◽

Vol 501 (1) ◽

pp. L60-L64

Author(s):

J Chauhan ◽

J C A Miller-Jones ◽

W Raja ◽

J R Allison ◽

P F L Jacob ◽

...

Keyword(s):

Black Hole ◽

Neutral Hydrogen ◽

Tangent Point ◽

X Ray ◽

Black Hole Candidate ◽

Upper Limit ◽

Local Standard ◽

Point Distance ◽

Spectral State ◽

Local Standard Of Rest

ABSTRACT We present neutral hydrogen (H i) absorption spectra of the black hole candidate X-ray binary (XRB) MAXI J1348–630 using the Australian Square Kilometre Array Pathfinder (ASKAP) and MeerKAT. The ASKAP H i spectrum shows a maximum negative radial velocity (with respect to the local standard of rest) of −31 ± 4 km s−1 for MAXI J1348–630, as compared to −50 ± 4 km s−1 for a stacked spectrum of several nearby extragalactic sources. This implies a most probable distance of $2.2^{+0.5}_{-0.6}$ kpc for MAXI J1348–630, and a strong upper limit of the tangent point distance at 5.3 ± 0.1 kpc. Our preferred distance implies that MAXI J1348–630 reached 17 ± 10 per cent of the Eddington luminosity at the peak of its outburst, and that the source transited from the soft to the hard X-ray spectral state at 2.5 ± 1.5 per cent of the Eddington luminosity. The MeerKAT H i spectrum of MAXI J1348–630 (obtained from the older, low-resolution 4k mode) is consistent with the re-binned ASKAP spectrum, highlighting the potential of the eventual capabilities of MeerKAT for XRB spectral line studies.

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Kink-driven magnetic reconnection in relativistic jets: consequences for X-ray polarimetry of BL Lacs

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3620 ◽

2020 ◽

Author(s):

G Bodo ◽

F Tavecchio ◽

L Sironi

Keyword(s):

Magnetic Reconnection ◽

Degree Of Polarization ◽

Polarization Angle ◽

Particle Injection ◽

X Ray ◽

Current Sheets ◽

Multi Wavelength ◽

Wavelength Emission ◽

Kink Instability ◽

Bl Lacs

Abstract We investigate with relativistic MHD simulations the dissipation physics of BL Lac jets, by studying the synchrotron polarization signatures of particles accelerated by the kink instability in a magnetically-dominated plasma column. The nonlinear stage of the kink instability generates current sheets, where particles can be efficiently accelerated via magnetic reconnection. We identify current sheets as regions where s = Jδ/B is above some predefined threshold (where B is the field strength, J the current density and δ the grid scale), and assume that the particle injection efficiency scales as ∝J2. X-ray emitting particles have short cooling times, so they only probe the field geometry of their injection sites. In contrast, particles emitting in the optical band, which we follow self-consistently as they propagate away from their injection sites while cooling, sample a larger volume, and so they may be expected to produce different polarimetric signatures. We find that the degree of polarization is roughly the same between X-ray and optical bands, because even the optical-emitting particles do not travel far from the current sheet where they were injected, due to lack of sufficient kink-generated turbulence. The polarization angle shows a different temporal evolution between the two bands, due to the different regions probed by X-ray and optical emitting particles. In view of the upcoming IXPE satellite, our results can help constrain whether kink-induced reconnection (as opposed to shocks) can be the source of multi-wavelength emission from BL Lacs.

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Multi-wavelength observations of the Blazar 4C +28.07

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab3538 ◽

2021 ◽

Author(s):

Davit Zargaryan ◽

Jonathan Mackey ◽

Thibault Barnouin ◽

Felix Aharonian

Keyword(s):

Photon Absorption ◽

Spectral Energy ◽

X Ray ◽

Radiation Fields ◽

Hole Radius ◽

Line Region ◽

Spectrum Radio ◽

Multi Wavelength ◽

Wavelength Emission ◽

Γ Ray

Abstract The active galactic nucleus 4C +28.07 is a flat spectrum radio quasar, one of the brightest at γ-ray energies. We study its multi-wavelength emission by analysing ∼12.3 years of Fermi-LAT data in the γ-ray band and Swift-XRT/UVOT available data in X-ray and Optical-to-Ultraviolet bands. In the γ-ray band, five flaring periods have been detected, and quasi-simultaneously with these flaring times, the X-ray and UVOT data detected by Swift-XRT/UVOT have also been analysed. In one of the brightest flare periods (Flare 5; observed on Oct 12, 2018) the γ-ray flux reached (6.7 ± 0.81) × 10−6 photon cm−2 s−1 (∼31 × higher than the mean flux over 12.3 years) with detection significance of σ = 6.1. The estimated variability time(∼2 hours) constrains the γ-ray emitting region size to ≤9 × 1014 cm, which is close to the black hole radius. The spectral energy distributions (SEDs) in the γ-ray band for the ∼12.3 years of data show an early cut-off at ∼14 GeV; beyond ∼60 GeV, however, the spectrum hardens and is detected up to ∼316 GeV. Similar spectral behaviour is also noticeable for the SEDs of flares, which can be linked to the photon absorption by the emitting region’s internal and external narrow-band radiation fields. In the quiescent period, the γ-ray emission was described by the Synchrotron-Self-Compton scenario, while the external photons contributions from the Disk and the broad-line region were required to explain the short-term flaring γ-ray emission. Considering the significance of the obtained results from 4C +28.07, we compared the parameters with 3C 279 and M87, to motivate further studies.

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Triggering nuclear and galaxy activity in the Bullet cluster

Astronomy and Astrophysics ◽

10.1051/0004-6361/201833601 ◽

2020 ◽

Vol 634 ◽

pp. A137

Author(s):

S. Puccetti ◽

F. Fiore ◽

A. Bongiorno ◽

K. Boutsia ◽

R. Fassbender ◽

...

Keyword(s):

Infrared Emission ◽

Point Sources ◽

Photometric Redshifts ◽

X Ray ◽

Cluster Galaxies ◽

Star Forming ◽

Multi Wavelength ◽

Cluster Environment ◽

Infrared Sources ◽

Trigger Mechanisms

The analysis of a cluster environment is a valuable instrument to investigate the origin of gas fuelling and trigger mechanisms in active galactic nuclei (AGN) and star-forming galaxies. To this purpose, we present a detailed analysis of the point-like X-ray sources in the Bullet cluster field. Based on ∼600 ks Chandra observations, we produced a catalogue of 381 X-ray point sources up to a distance of ∼1.5 virial radius and with flux limits ∼1 × 10−16 and ∼8 × 10−16 erg cm−2 s−1 in the 0.5–2 keV and 2–10 keV bands, respectively. We find a strong (up to a factor 1.5–2) and significant (≥4σ) over-density in the full region studied 0.3R200 < R < 1.5R200. We identified optical (R band) and infrared (Spitzer IRAC) counterparts for ∼84% and ∼48% of the X-ray sources, respectively. We obtained new spectroscopic redshifts for 106 X-ray sources and collected from the literature additional 13 spectroscopic and 8 photometric redshifts of X-ray sources. Twenty-nine X-ray sources turned out to be cluster members. Spectroscopic and photometric redshifts of optical and infrared sources were also collected, and these sources were used as ancillary samples. We used these multi-wavelength data to characterise the nature of the Bullet cluster X-ray point sources. We find that the over-density in the region 0.3R200 < R < R200 is likely due to X-ray AGN (mostly obscured) and star-forming galaxies associated with the cluster, while in the more external region this over-density is likely to be mostly due to background AGN. The fraction of cluster galaxies hosting an X-ray detected AGN is 1.0 ± 0.4%, which is nearly constant with the radius; this fraction is similar to that reported in other clusters of galaxies at similar redshift. The fraction of X-ray bright AGN (L2 − 10 keV > 1043 ergs s−1) in the region 0.3R200 < R < R200 is 0.5−0.2+0.6%, which is higher than that in other clusters at similar redshift and more similar to the AGN fraction in the field. Finally, the spatial distributions of AGN and star-forming galaxies, which we selected for their infrared emission, appear similar, thus suggesting that both are triggered by the same mechanism.

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The First Systematic Multi-wavelength Survey of Extragalactic Supernova Remnants

Proceedings of the International Astronomical Union ◽

10.1017/s1743921313009502 ◽

2013 ◽

Vol 9 (S296) ◽

pp. 222-225

Author(s):

I. Leonidaki ◽

P. Boumis ◽

A. Zezas

Keyword(s):

Supernova Remnants ◽

Star Formation Rate ◽

Narrow Band ◽

Formation Rate ◽

Host Galaxies ◽

X Ray ◽

Different Types ◽

Multi Wavelength ◽

Nearby Galaxies ◽

Optically Detected

AbstractWe present the largest sample of multi-wavelength Supernova Remnants (SNRs) in six nearby galaxies, based on Chandra archival data and deep optical narrow-band Hα and [Sii] images as well as spectroscopic observations. We have identified 37 X-ray selected thermal SNRs, 30 of which are new identifications and ~ 400 optical SNRs, for 67 of which we spectroscopically verified their shock-excited nature. We discuss the properties of the X-ray/optically detected SNRs in different types of galaxies and hence different environments, in order to address their dependence on their Interstellar Medium (ISM). We also discuss the SNR populations in the context of the star formation rate of their host galaxies. We cross-correlate parameters of the optically detected SNRs with parameters of coincident X-ray emitting SNRs in order to understand their evolution and investigate possible selection effects.

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