Journal articles on the topic 'Outflows supernova remnants ISM'
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1
Chu, You-Hua. "CSI in Supernova Remnants." Proceedings of the International Astronomical Union 12, S331 (February 2017): 81–85. http://dx.doi.org/10.1017/s1743921317004926.
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AbstractSupernovae (SNe) explode in environments that have been significantly modified by the SN progenitors. For core-collapse SNe, the massive progenitors ionize the ambient interstellar medium (ISM) via UV radiation and sweep the ambient ISM via fast stellar winds during the main sequence phase, replenish the surroundings with stellar material via slow winds during the luminous blue variable (LBV) or red supergiant (RSG) phase, and sweep up the circumstellar medium (CSM) via fast winds during the Wolf-Rayet (WR) phase. If a massive progenitor was in a close binary system, the binary interaction could have caused mass ejection in certain preferred directions, such as the orbital plane, and even bipolar outflow/jet. As a massive star finally explodes, the SN ejecta interacts first with the CSM that was ejected and shaped by the star itself. As the newly formed supernova remnant (SNR) expands further, it encounters interstellar structures that were shaped by the progenitor from earlier times. Therefore, the structure and evolution of a SNR is largely dependent on the initial mass and close binarity of the SN progenitor. The Large Magellanic Cloud (LMC) has an excellent sample of over 50 confirmed SNRs that are well resolved by Hubble Space Telescope, Chandra X-ray Observatory, and Spitzer Space Telescope. These multi-wavelength observations allow us to conduct stellar forensics in SNRs and understand the wide variety of morphologies and physical properties of SNRs observed.
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Gusdorf, Antoine. "Feedback from young stars, the molecular signature of shocks and outflows." EPJ Web of Conferences 265 (2022): 00035. http://dx.doi.org/10.1051/epjconf/202226500035.
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Why do we study shocks ? Because they are there. Shocks are ubiquitous in the interstellar medium (ISM), where they constitute a major source of energy injection, together with photons and cosmic rays (CRs). Galactic shocks, and converging flows at the basis of the formation of molecular clouds and filaments, are examples of interstellar shocks. Shock waves are also generated during the birth, life and death of stars in the form of jets and protostellar outflows, stellar winds and supernovae and supernova remnants (SNRs). Hence, they are a major route of feedback of stars on galaxies. As such, they are a proficient tool to better understand the cycle of matter and energy in galaxies, but also the formation of stars. In this review, I will describe the recent advances on the study of shocks that can be observed and characterized with the IRAM instruments, with emphasis on the study of protostellar jets and outflows.
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Petre, R. "Supernova Remnants in the Magellanic Clouds." Symposium - International Astronomical Union 190 (1999): 74–77. http://dx.doi.org/10.1017/s0074180900117425.
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Over the past decade, substantial progress has been made in understanding the properties of Magellanic Cloud supernova remnants and their role in the ISM. Among the notable results are the “typing” of progenitors via the X-ray spectra of their remnants, the use of X-ray spectra to measure ISM abundances, and the discovery of remnants with unique properties. I summarize recent studies of MC SNRs, and describe how a refined understanding of the SNR population requires consideration of the unique attributes of each remnant.
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Wu, D., M. F. Zhang, S. S. Shan, and W. W. Tian. "MHD Simulation of Supernova Remnants." Proceedings of the International Astronomical Union 12, S331 (February 2017): 174–77. http://dx.doi.org/10.1017/s1743921317004902.
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AbstractWe present some Magnetohydrodynamic (MHD) simulations for supernova remnants (SNRs), which hints the thicknesses of SNRs’ shells are likely related to the density and density distribution of surrounding interstellar medium (ISM). The simulations show clear formation and evolution of reverse shocks. In addition, we find that stellar winds can blow a bubble around the progenitor stars then lead to weaker radio emission at the center of SNRs.
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Wandel, Amri. "Supernova Remnants and the ISM: Constraints from Cosmic-Ray Acceleration." International Astronomical Union Colloquium 101 (1988): 325–29. http://dx.doi.org/10.1017/s0252921100102581.
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AbstractSupernova remnants can reaccelerate cosmic rays and modify their distribution during the cosmic ray propagation in the galaxy. Cosmic ray observations (in particular the boron-to-carbon data) strongly limit the permitted amount of reacceleration, which is used to set an upper limit on the expansion of supernova remnants, and a lower limit on the effective density of the ISM swept up by supernova shocks. The constraint depends on the theory of cosmic ray propagation: the standard Leaky Box model requires a high effective density, > 1cm−3, and is probably inconsistent with the present picture of the ISM. Modifying the Leaky Box model to include a moderate amount of weak-shock reacceleration, a self consistent solution is found, where the effective density in this solution is ≈ 0.1 cm−3, which implies efficient evaporation of the warm ISM component by young supernova remnants, during most of their supersonic expansion.
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Zhu, Hui, and Wenwu Tian. "Distances of Galactic supernova remnants." Proceedings of the International Astronomical Union 9, S296 (January 2013): 378–79. http://dx.doi.org/10.1017/s1743921313009915.
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AbstractSupernova remnants (SNRs) play a key role in understanding supernovae explosion mechanisms, exploring the likely sources of Galactic cosmic rays and the chemical enrichment of interstellar medium (ISM). Reliable distance determinations to Galactic SNRs are key to obtain their basic parameters, such as size, age, explosion energy, which helps us to study their environment and interstellar medium. We review the methods to determine the distances to SNRs and highlight the kinematic distance measurement by Hi absorption and CO emission observations.
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Fujita, Y., J. Fukumoto, and K. Okoshi. "Evolution of Multiphase Hot Interstellar Medium in Elliptical Galaxies." Symposium - International Astronomical Union 188 (1998): 281–82. http://dx.doi.org/10.1017/s007418090011513x.
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Theoretical arguments indicate that the ISM is inhomogeneous; Mathews estimated that the ~ 1M⊙ of metal ejected by each supernova event into the ISM is trapped locally within the hot bubbles. Since in elliptical galaxies, there is no overlapping of expanding supernova remnants after galactic wind period, it is expected that this inhomogeneity persists for a long time. The observations also suggests that the ISM of elliptical galaxies is inhomogeneous. Based on these arguments, we studied the evolution of the multiphase (inhomogeneous) ISM.
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Meyer, D. M.-A., M. Pohl, M. Petrov, and L. Oskinova. "Non-thermal radio supernova remnants of exiled Wolf–Rayet stars." Monthly Notices of the Royal Astronomical Society 502, no. 4 (February 17, 2021): 5340–55. http://dx.doi.org/10.1093/mnras/stab452.
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ABSTRACT A signification fraction of Galactic massive stars (${\ge}8\, \rm M_{\odot }$) are ejected from their parent cluster and supersonically sail away through the interstellar medium (ISM). The winds of these fast-moving stars blow asymmetric bubbles thus creating a circumstellar environment in which stars eventually die with a supernova explosion. The morphology of the resulting remnant is largely governed by the circumstellar medium of the defunct progenitor star. In this paper, we present 2D magneto-hydrodynamical simulations investigating the effect of the ISM magnetic field on the shape of the supernova remnants of a $35\, \mathrm{M}_{\odot }$ star evolving through a Wolf–Rayet phase and running with velocity 20 and $40\, \rm km\, \rm s^{-1}$, respectively. A $7\, \mu \rm G$ ambient magnetic field is sufficient to modify the properties of the expanding supernova shock front and in particular to prevent the formation of filamentary structures. Prior to the supernova explosion, the compressed magnetic field in the circumstellar medium stabilizes the wind/ISM contact discontinuity in the tail of the wind bubble. A consequence is a reduced mixing efficiency of ejecta and wind materials in the inner region of the remnant, where the supernova shock wave propagates. Radiative transfer calculations for synchrotron emission reveal that the non-thermal radio emission has characteristic features reflecting the asymmetry of exiled core-collapse supernova remnants from Wolf–Rayet progenitors. Our models are qualitatively consistent with the radio appearance of several remnants of high-mass progenitors, namely the bilateral G296.5+10.0 and the shell-type remnants CTB109 and Kes 17, respectively.
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McKee, Christopher F. "Supernova Remnant Shocks in an Inhomogeneous Interstellar Medium." International Astronomical Union Colloquium 101 (1988): 205–22. http://dx.doi.org/10.1017/s0252921100102386.
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AbstractThe inhomogeneity of the interstellar medium (ISM) has a profound effect on the propagation of the interstellar shock generated by a supernova and on the appearance of the resulting supernova remnant (SNR). Low mass supernovae produce remnants that interact with the “pristine” ISM, which has density inhomogeneities (clouds) on a wide range of scales. The shock compresses and accelerates the clouds it encounters; inside the blast wave, the clouds are hydrodynamically unstable, and mass is injected from the clouds into the intercloud medium. Embedded clouds interact thermally with the shock also, adding mass to the hot intercloud medium via thermal evaporation or subtracting it via condensation and thermal instability. Mass injection into the hot intercloud medium, whether dynamical or thermal, leads to infrared emission as dust mixes with the hot gas and is thermally sputtered. The remnants of massive supernovae interact primarily with circumstellar matter and with interstellar material which has been processed by the ionizing radiation and wind of the progenitor star. After passing through any circumstellar material which may be present, the shock encounters a cavity which tends to “muffle” the SNR. The remnants of massive supernovae therefore tell us more about the late stages of the evolution of massive stars than about the ISM.
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Kemball, Athol J. "Stellar masers, circumstellar envelopes and supernova remnants." Proceedings of the International Astronomical Union 3, S242 (March 2007): 236–45. http://dx.doi.org/10.1017/s1743921307013063.
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AbstractThis paper reviews recent advances in the study or circumstellar masers and masers found toward supernova remnants. The review is organized by science focus area, including the astrophysics of extended stellar atmospheres, stellar mass-loss processes and outflows, late-type evolved stellar evolution, stellar maser excitation and chemistry, and the use of stellar masers as independent distance estimators. Masers toward supernova remnants are covered separately. Recent advances and open future questions in this field are explored.
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Wang, Zhenru. "Historical Supernovae and Supernova Remnants." International Astronomical Union Colloquium 145 (1996): 323–31. http://dx.doi.org/10.1017/s0252921100008174.
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The oldest historical supernova (SN), recorded by ancient Chinese in 14th Century B.C. on pieces of tortoise shells or bones, is identified with the aid of modern space γ-ray observations. Hard X-rays with energy up to 20 keV were observed from IC 443 by the X-ray satellite Ginga. We infer from these observations the age of IC 443 is ∼ 1000 — 1400 yrs. The result supports the hypothesis that IC 443 is the remnant of the historical SN 837 that occurred during the Tang Dynasty. The association between the supernova remnant (SNR) CTB 80 and SN 1408 has been hotly debated for about ten years and is briefly reviewed and discussed here. A new picture is presented to explain this association. High energy emission from historical SNRs can persist in a multiphase interstellar medium (ISM). As a result, the study of the relationship between SNRs and ancient guest stars has gained new vitality.
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Kostic, P. "A new numerical code for hydrodynamical 3D simulations of supernova remnants." Serbian Astronomical Journal, no. 199 (2019): 65–82. http://dx.doi.org/10.2298/saj1999065k.
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We develop a 3D hydrodynamical code written in C programming language to study the expansion of supernova remnants (SNRs) in the surrounding medium. It is based on the MUSCL-Hancock finite volume scheme with the HLLC Riemann solver. The code initiates the supernova remnant already in the Sedov phase and simulates hydrodynamics of the subsequent remnant expansion. The simulation is optimized for studies of large scale interaction of a supernova remnant with the interstellar medium (ISM). After a detailed description of the code, and three tests of hydrodynamics, we present the results for a single remnant expanding into a uniform and fractally structured ISM, as the first application of the code. The simulation of SNR expanding in a uniform medium is compared with the Sedov law of expansion and Sedov self-similar solution to density, velocity and pressure profiles. The results indicate that the simulation presented here reproduces well the hydrodynamics of the supernova remnant expansion and is very practical due to its simplicity and speed. The SNR evolution in fractal ISM shows that clumps disturb the blast wave and produce interference of bow shocks, resulting in turbulent motions and inhomogenities inside the remnant.
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TELEZHINSKY, IGOR, and BOHDAN HNATYK. "HIGH ENERGY SIGNATURES OF POST ADIABATIC SUPERNOVA REMNANTS." Modern Physics Letters A 22, no. 35 (November 20, 2007): 2617–29. http://dx.doi.org/10.1142/s0217732307025601.
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Between the well-known adiabatic and radiative stages of the Supernova remnant (SNR) evolution there is, in fact, a transition stage with a duration comparable to the duration of adiabatic one. Physical existence of the transition stage is motivated by cooling of some part of the downstream hot gas with formation of a thin cold shell that is joined to a shell of swept up interstellar medium (ISM). We give an approximate analytical method for full hydrodynamical description of the transition stage. On its base we investigate the evolution of X-ray and γ-ray radiation during this stage. It is shown that formation of a dense shell during the transition stage is accompanied by the decrease of X-ray luminosity because of hot gas cooling and increase of gamma-ray flux according to the increase of target proton density and CR energy in the newly born shell. The role of nonuniformity of ISM and its influence on the high energy fluxes from the SNRs is also discussed.
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Orr, Matthew E., Drummond B. Fielding, Christopher C. Hayward, and Blakesley Burkhart. "Bursting Bubbles: Clustered Supernova Feedback in Local and High-redshift Galaxies." Astrophysical Journal Letters 924, no. 2 (January 1, 2022): L28. http://dx.doi.org/10.3847/2041-8213/ac479f.
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Abstract We compare an analytic model for the evolution of supernova-driven superbubbles with observations of local and high-redshift galaxies, and the properties of intact H i shells in local star-forming galaxies. Our model correctly predicts the presence of superwinds in local star-forming galaxies (e.g., NGC 253) and the ubiquity of outflows near z ∼ 2. We find that high-redshift galaxies may “capture” 20%–50% of their feedback momentum in the dense ISM (with the remainder escaping into the nearby CGM), whereas local galaxies may contain ≲10% of their feedback momentum from the central starburst. Using azimuthally averaged galaxy properties, we predict that most superbubbles stall and fragment within the ISM, and that this occurs at, or near, the gas scale height. We find a consistent interpretation in the observed H i bubble radii and velocities, and predict that most will fragment within the ISM, and that those able to break out originate from short dynamical time regions (where the dynamical time is shorter than feedback timescales). Additionally, we demonstrate that models with constant star cluster formation efficiency per Toomre mass are inconsistent with the occurrence of outflows from high-z starbursts and local circumnuclear regions.
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Sarbadhicary, Sumit K., Carles Badenes, Laura Chomiuk, Damiano Caprioli, and Daniel Huizenga. "Supernova remnants in the Local Group – I. A model for the radio luminosity function and visibility times of supernova remnants." Monthly Notices of the Royal Astronomical Society 464, no. 2 (October 8, 2016): 2326–40. http://dx.doi.org/10.1093/mnras/stw2566.
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Abstract Supernova remnants (SNRs) in Local Group galaxies offer unique insights into the origin of different types of supernovae (SNe). In order to take full advantage of these insights, one must understand the intrinsic and environmental diversity of SNRs in the context of their host galaxies. We introduce a semi-analytic model that reproduces the statistical properties of a radio continuum-selected SNR population, taking into account the detection limits of radio surveys, the range of SN kinetic energies, the measured interstellar medium (ISM) and stellar mass distribution in the host galaxy from multi-wavelength images and the current understanding of electron acceleration and magnetic field amplification in SNR shocks from first-principle kinetic simulations. Applying our model to the SNR population in M33, we reproduce the SNR radio luminosity function with a median SN rate of ∼3.1 × 10−3 per year and an electron acceleration efficiency, εe ∼ 4.2 × 10−3. We predict that the radio visibility times of ∼70 per cent of M33 SNRs will be determined by their Sedov–Taylor lifetimes, and correlated with the measured ISM column density, NH ($t_{\rm {vis}} \propto N_{\rm H}^{-a}$, with a ∼ 0.33) while the remaining will have visibility times determined by the detection limit of the radio survey. These observational constraints on the visibility time of SNRs will allow us to use SNR catalogues as ‘SN surveys’ to calculate SN rates and delay-time distributions in the Local Group.
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Duric, N., S. M. Gordon, W. M. Goss, F. Viallefond, and C. Lacey. "The relativistic ISM in M33: Role of the supernova remnants." Astrophysical Journal 445 (May 1995): 173. http://dx.doi.org/10.1086/175683.
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Gusdorf, A., R. Güsten, S. Anderl, T. Hezareh, and H. Wiesemeyer. "The molecular emission from old supernova remnants." Proceedings of the International Astronomical Union 9, S296 (January 2013): 178–82. http://dx.doi.org/10.1017/s1743921313009435.
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AbstractSupernovae constitute a critical source of energy input to the interstellar medium (ISM). In this short review, we focus on their latest phase of evolution, the supernova remnants (SNRs). We present observations of three old SNRs that have reached the phase where they interact with the ambient interstellar medium: W28, IC443, and 3C391. We show that such objects make up clean laboratories to constrain the physical and chemical processes at work in molecular shock environments. Our studies subsequently allow us to quantify the impact of SNRs on their environment in terms of mass, momentum, and energy dissipation. In turn, their contribution to the energy balance of galaxies can be assessed. Their potential to trigger a further generation of star formation can also be investigated. Finally, our studies provide strong support for the interpretation of γ-ray emission in SNRs, a crucial step to answer questions related to cosmic rays population and acceleration.
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Meyer, D. M.-A., M. Petrov, and M. Pohl. "Wind nebulae and supernova remnants of very massive stars." Monthly Notices of the Royal Astronomical Society 493, no. 3 (February 26, 2020): 3548–64. http://dx.doi.org/10.1093/mnras/staa554.
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ABSTRACT A very small fraction of (runaway) massive stars have masses exceeding $60\!-\!70\, \rm M_{\odot }$ and are predicted to evolve as luminous blue variable and Wolf–Rayet stars before ending their lives as core-collapse supernovae. Our 2D axisymmetric hydrodynamical simulations explore how a fast wind ($2000\, \rm km\, \rm s^{-1}$) and high mass-loss rate ($10^{-5}\, \rm M_{\odot }\, \rm yr^{-1}$) can impact the morphology of the circumstellar medium. It is shaped as 100 pc-scale wind nebula that can be pierced by the driving star when it supersonically moves with velocity $20\!-\!40\, \rm km\, \rm s^{-1}$ through the interstellar medium (ISM) in the Galactic plane. The motion of such runaway stars displaces the position of the supernova explosion out of their bow shock nebula, imposing asymmetries to the eventual shock wave expansion and engendering Cygnus-loop-like supernova remnants. We conclude that the size (up to more than $200\, \rm pc$) of the filamentary wind cavity in which the chemically enriched supernova ejecta expand, mixing efficiently the wind and ISM materials by at least $10{{\ \rm per\ cent}}$ in number density, can be used as a tracer of the runaway nature of the very massive progenitors of such $0.1\, \rm Myr$ old remnants. Our results motivate further observational campaigns devoted to the bow shock of the very massive stars BD+43°3654 and to the close surroundings of the synchrotron-emitting Wolf–Rayet shell G2.4+1.4.
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Katsuragawa, Miho, Shiu-Hang Lee, Hirokazu Odaka, Aya Bamba, Hideaki Matsumura, and Tadayuki Takahashi. "On the Formation of Over-ionized Plasma in Evolved Supernova Remnants." Astrophysical Journal 938, no. 1 (October 1, 2022): 23. http://dx.doi.org/10.3847/1538-4357/ac8cf9.
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Abstract One of the outstanding mysteries surrounding the rich diversity found in supernova remnants (SNRs) is the recent discovery of over-ionized or recombining plasma from a number of dynamically evolved objects. To help decipher its formation mechanism, we have developed a new simulation framework capable of modeling the time evolution of the ionization state of the plasma in an SNR. The platform is based on a one-dimensional hydrodynamics code coupled to a fully time-dependent nonequilibrium ionization calculation, accompanied by a spectral synthesis code to generate space-resolved broadband X-ray spectra for SNRs at arbitrary ages. We perform a comprehensive parametric survey to investigate the effects of different circumstellar environments on the ionization state evolution in SNRs up to a few 104 yr. A two-dimensional parameter space, spanned by arrays of interstellar medium (ISM) densities and mass-loss rates of the progenitor, is used to create a grid of models for the surrounding environment, in which a core-collapse explosion is triggered. Our results show that a recombining plasma can be successfully reproduced in the case of a young SNR (a few 100 to 1000 yr old) expanding fast in a spatially extended low-density wind, an old SNR (>a few 1000 yr) expanding in a dense ISM, or an old SNR broken out from a confined dense wind region into a tenuous ISM. Finally, our models are confronted with observations of evolved SNRs, and an overall good agreement is found except for a couple of outliers.
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Xu, Siyao. "Mirror Diffusion of Cosmic Rays in Highly Compressible Turbulence Near Supernova Remnants." Astrophysical Journal 922, no. 2 (December 1, 2021): 264. http://dx.doi.org/10.3847/1538-4357/ac2d8f.
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Abstract Recent gamma-ray observations have revealed inhomogeneous diffusion of cosmic rays (CRs) in the interstellar medium (ISM). This is expected, as the diffusion of CRs depends on the properties of turbulence, which can vary widely in the multiphase ISM. We focus on the mirror diffusion arising in highly compressible turbulence in molecular clouds (MCs) around supernova remnants (SNRs), where the magnetic mirroring effect results in significant suppression of diffusion of CRs near CR sources. Significant energy loss via proton–proton interactions due to slow diffusion flattens the low-energy CR spectrum, while the high-energy CR spectrum is steepened due to the strong dependence of mirror diffusion on CR energy. The resulting broken power-law spectrum of CRs matches well the gamma-ray spectrum observed from SNR/MC systems, e.g., IC443 and W44.
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Yasuda, Haruo, Shiu-Hang Lee, and Keiichi Maeda. "Resurrection of Nonthermal Emissions from Type Ib/c Supernova Remnants." Astrophysical Journal 925, no. 2 (February 1, 2022): 193. http://dx.doi.org/10.3847/1538-4357/ac3b49.
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Abstract Supernova remnants (SNRs) are important objects in investigating the links among supernova (SN) explosion mechanism(s), progenitor stars, and cosmic-ray acceleration. Nonthermal emission from SNRs is an effective and promising tool for probing their surrounding circumstellar media (CSM) and, in turn, the stellar evolution and mass-loss mechanism(s) of massive stars. In this work, we calculate the time evolution of broadband nonthermal emissions from Type Ib/c SNRs, whose CSM structures are derived from the mass-loss history of their progenitors. Our results predict that Type Ib/c SNRs make a transition of brightness in radio and γ-ray bands from an undetectable dark for a certain period to a rebrightening phase. This transition originates from their inhomogeneous CSM structures in which the SNRs are embedded within a low-density wind cavity surrounded by a high-density wind shell and the ambient interstellar medium (ISM). The “resurrection” in nonthermal luminosity happens at an age of ∼1000 yr old for a Wolf-Rayet star progenitor evolved within a typical ISM density. Combining with the results of Type II SNR evolution recently reported by Yasuda et al., this result sheds light on a comprehensive understanding of nonthermal emissions from SNRs with different SN progenitor types and ages, which is made possible for the first time by the incorporation of realistic mass-loss histories of the progenitors.
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Labrie, Kathleen, and Chris J. Pritchet. "The impact of supernova remnants on the ISM in Starburst galaxies." Proceedings of the International Astronomical Union 2004, IAUS222 (March 2004): 185–86. http://dx.doi.org/10.1017/s1743921304001966.
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Williams, Rosa N. M. "Supernova remnants in the Magellanic Clouds." Proceedings of the International Astronomical Union 4, S256 (July 2008): 443–53. http://dx.doi.org/10.1017/s1743921308028846.
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AbstractAt the 1998 IAU Symposium on the Magellanic Clouds, Dr. Robert Petre observed that we were reaching a time where it was possible “to study the MC SNRs at a level of detail comparable with many Galactic remnants”, while retaining the benefits of a global view in the MCs. Over the past decade, many researchers have taken advantage of these newly accessible populations. New MC-wide surveys at various wavelengths have enabled broader searches for SNR candidates, extending our census of MC SNRs to less prominent objects — older SNRs, SNRs in complex regions, et cetera. The use of light-echoes has provided a new avenue to probe young SNRs. Higher spatial and spectral resolutions in many wavelength regimes have enabled detailed studies of individual remnants, revealing progenitor types, pulsar-wind nebulae, expansion details, and environmental effects.Perhaps the newest conceptual development is the increasing use of the MC SNRs to study physical problems of wider significance to many fields of astronomy. For example, researchers have examined the energy and hot gas inputs of MC SNRs to the ISM, including their collective effects within superbubbles, in order to evaluate their effects on stellar feedback cycles in a galaxy. Other scientists have investigated the fraction of SNR energies going to the acceleration of cosmic rays, which has significant implications for the role of SNRs in cosmic-ray production. Most recently, the onslaught of Spitzer data has led to new exploration of dust in MC SNRs, allowing us to probe dust creation, depletion, and destruction in the MC SNR populations. In summary, the study of SNRs in the MCs appears to have “come of age” over the past decade, becoming a mature field with rich potential for future scientific work.
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Dubner, Gloria. "Radio Observations of Supernova Remnants and the Surrounding Interstellar Medium." Symposium - International Astronomical Union 199 (2002): 284–90. http://dx.doi.org/10.1017/s0074180900169128.
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Supernova Remnants (SNRs) play essential roles in the dynamics of galaxies by injecting large amounts of energy which can accelerate particles generating cosmic radiation, create large, hot, low density bubbles, and maintain turbulent cloud motions. SNRs shock waves can also compress nearby dense clouds, inducing fragmentation and perhaps collapse into protostars, thus joining the extremes in the life-cycle of stars. The present review illustrates how high quality low frequencies radio observations of galactic SNRs and the surrounding interstellar medium (ISM), can help in the understanding of the many aspects of the nature of the remnants, as well as the consequences of their interaction with the ambient gas.
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Chu, You-Hua. "Multi-wavelength View of the Interstellar Medium in the Large Magellanic Cloud." Publications of the Astronomical Society of Australia 15, no. 1 (1998): 136–40. http://dx.doi.org/10.1071/as98136.
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AbstractThe Large Magellanic Cloud (LMC) has been surveyed in optical emission lines, X-rays, radio continuum, HI, and CO lines. These surveys provide views of the interstellar medium (ISM) in the LMC of unprecedented clarity, allowing us to study astrophysical processes and to examine the relationship among the different phases of the ISM. Multi-wavelength images are used to illustrate the physical structures of supernova remnants, superbubbles, and supergiant shells, as well as the global interstellar structure of the LMC.
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Wang, Zhenru. "The Morphologies of SNRs and Their ISM and CSM." Symposium - International Astronomical Union 188 (1998): 260–61. http://dx.doi.org/10.1017/s0074180900115037.
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Recently, many unusual morphologies of supernova remnants (SNRs) have been discovered: semicircular shell; center-brightened but without center point source; two-lobed; bipolar; irregular, etc. To understand these varieties of morphologies, we have made theoretical models. One of the main reasons of their unusualness is the multiphase structure of the interstellar medium (ISM) and circumstellar medium (CSM) where they evolved, and the CSM is connected with their progenitor.
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Sarbadhicary, Sumit K., Davide Martizzi, Enrico Ramirez-Ruiz, Eric Koch, Katie Auchettl, Carles Badenes, and Laura Chomiuk. "Testing the Momentum-driven Supernova Feedback Paradigm in M31." Astrophysical Journal 928, no. 1 (March 1, 2022): 54. http://dx.doi.org/10.3847/1538-4357/ac3094.
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Abstract Momentum feedback from isolated supernova remnants (SNRs) have been increasingly recognized by modern cosmological simulations as a resolution-independent means to implement the effects of feedback in galaxies, such as turbulence and winds. However, the integrated momentum yield from SNRs is uncertain due to the effects of SN clustering and interstellar medium (ISM) inhomogeneities. In this paper, we use spatially resolved observations of the prominent 10 kpc star-forming ring of M31 to test models of mass-weighted ISM turbulence driven by momentum feedback from isolated, nonoverlapping SNRs. We use a detailed stellar age distribution (SAD) map from the Panchromatic Hubble Andromeda Treasury survey, observationally constrained SN delay-time distributions, and maps of the atomic and molecular hydrogen to estimate the mass-weighted velocity dispersion using the Martizzi et al. ISM turbulence model. Our estimates are within a factor of two of the observed mass-weighted velocity dispersion in most of the ring, but exceed observations at densities ≲0.2 cm−3 and SN rates >2.1 × 10−4 SN yr−1 kpc−2, even after accounting for plausible variations in SAD models and ISM scale height assumptions. We conclude that at high SN rates the momentum deposited is most likely suppressed by the nonlinear effects of SN clustering, while at low densities, SNRs reach pressure equilibrium before the cooling phase. These corrections should be introduced in models of momentum-driven feedback and ISM turbulence.
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Hanasz, M., D. Wóltanski, K. Kowalik, and H. Kotarba. "Cosmic-ray driven dynamo in galaxies." Proceedings of the International Astronomical Union 6, S274 (September 2010): 355–60. http://dx.doi.org/10.1017/s1743921311007265.
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AbstractWe present recent developments of global galactic-scale numerical models of the Cosmic Ray (CR) driven dynamo, which was originally proposed by Parker (1992). We conduct a series of direct CR+MHD numerical simulations of the dynamics of the interstellar medium (ISM), composed of gas, magnetic fields and CR components. We take into account CRs accelerated in randomly distributed supernova (SN) remnants, and assume that SNe deposit small-scale, randomly oriented, dipolar magnetic fields into the ISM. The amplification timescale of the large-scale magnetic field resulting from the CR-driven dynamo is comparable to the galactic rotation period. The process efficiently converts small-scale magnetic fields of SN-remnants into galactic-scale magnetic fields. The resulting magnetic field structure resembles the X-shaped magnetic fields observed in edge-on galaxies.
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Feijen, K., S. Einecke, G. Rowell, C. Braiding, M. G. Burton, and G. F. Wong. "Modelling the gamma-ray morphology of HESSJ1804−216 from two supernova remnants in a hadronic scenario." Monthly Notices of the Royal Astronomical Society 511, no. 4 (February 15, 2022): 5915–26. http://dx.doi.org/10.1093/mnras/stac320.
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ABSTRACT HESS J1804−216 is one of the brightest yet most mysterious TeV γ-ray sources discovered to date. Previous arc-minute scale studies of the interstellar medium (ISM) surrounding this TeV γ-ray source revealed HESS J1804−216 is likely powered by a mature supernova remnant (SNR) or pulsar, hence its origin remains uncertain. In this paper, we focus on the diffusive escape of cosmic ray protons from potential SNR accelerators. These cosmic rays interact with the ISM to produce TeV γ-rays. We utilize the isotropic diffusion equation solution for particles escaping from a shell, to model the energy-dependent escape and propagation of protons into the ISM. This work is the first attempt at modelling the spatial morphology of γ-rays towards HESS J1804−216, using arc-minute ISM observations from both Mopra and the Southern Galactic Plane Survey. The spectral and spatial distributions of γ-rays for the two nearby potential SNR counterparts, SNR G8.7−0.1 and the progenitor SNR of PSR J1803−2137, are presented here. We vary the diffusion parameters and particle spectrum and use a grid search approach to find the best combination of model parameters. We conclude that moderately slow diffusion is required for both candidates. The most promising candidate to be powering the TeV γ-rays from HESS J1804−216 in a hadronic scenario is the progenitor SNR of PSR J1803−2137.
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Leonidaki, I., P. Boumis, and A. Zezas. "The First Systematic Multi-wavelength Survey of Extragalactic Supernova Remnants." Proceedings of the International Astronomical Union 9, S296 (January 2013): 222–25. http://dx.doi.org/10.1017/s1743921313009502.
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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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Hausman, M. A., and W. W. Roberts. "Spiral tracers and prestellar incubation periods in a cloudy interstellar medium." Symposium - International Astronomical Union 106 (1985): 571–72. http://dx.doi.org/10.1017/s0074180900243180.
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We present further results of our model of the interstellar medium in spiral galaxies (Roberts and Hausman, 1983; Hausman and Roberts, 1983). The ISM is simulated by a system of particles, representing gas clouds, which orbit ballistically in a spiral-perturbed galactic gravitational field, collide inelastically with one another, and receive velocity impulses from expanding supernova remnants. Star formation may be triggered in the clouds by either collisions or SNR interactions.
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Rho, J., M. Andersen, A. Tappe, H. Gomez, M. Smith, J. P. Bernard, T. Onaka, and J. Cami. "Dust and Molecule Formation and Processing in Supernovae and their Remnants." Proceedings of the International Astronomical Union 10, H16 (August 2012): 583–85. http://dx.doi.org/10.1017/s1743921314012277.
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AbstractSupernovae (SNe) produce, fragment and destroy dust, molecules and nucleosynthetic elements, and reshape and modify the ISM. I will review recent infrared observations of supernova remnants (SNRs) and SNe which show that SNe are important sites of dust and molecule formation and are major dust creators in the Universe. Detection of carbon monoxide (CO) fundamental band from the young SNR Cas A indicates that astrochemical processes in SNRs interacting with molecular clouds provide astrophysical laboratories to study evolution of the ISM returning material from dense clouds into the more diffuse medium and galactic halo. Two dozen SNRs are known to be interacting with molecular clouds using H2 and millimeter observations. Recent Spitzer, Herschel and SOFIA observations along with ground-based observations have greatly advanced our understanding shock processing and astrochemistry of dust, H2, high J CO, and other neutral and ionized molecules and polycyclic aromatic hydrocarbon (PAH). Ionized molecules and warm layer of molecules that are excited by UV radiation, X-rays, or cosmic rays will be described. Finally I will discuss how astrochemical processes of dust and molecules in SNRs impact the large scale structures in the ISM.
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McKee, Christopher F. "Dust Destruction in the Interstellar Medium." Symposium - International Astronomical Union 135 (1989): 431–44. http://dx.doi.org/10.1017/s0074180900125434.
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Grains are injected into the interstellar medium (ISM) from evolved stars and supernovae; in addition, supernova ejecta may condense onto pre-existing grains before becoming well-mixed with the interstellar gas. Once in the ISM, grains can grow by accretion, but are also subject to destruction by interstellar shocks. The current status of the theory of shock destruction of interstellar grains is reviewed briefly. Small grains are destroyed by thermal sputtering in fast, nonradiative shocks; large grains are destroyed by grain-grain collisions and eroded by nonthermal sputtering in radiative shocks. The dominant shocks in the ISM are from supernova remnants (SNRs), and the mass of grains destroyed is proportional to the energy of the SNR. In a multiphase ISM, these shocks destroy the grains at a rate proportional to the volume filling factor of the phase; since the density of the hot phase is too low for efficient grain destruction, most of the destruction occurs in the warm phase. Not all SNRs are effective at destroying grains, however: some are above the gas disk, and some —Type IPs in associations—are highly correlated in space and time. The galactic SN rate is observed to about 2.2 per century (van den Bergh, 1983), but the effective supernova rate for grain destruction is estimated to be only about 0.8 per century. As a result, the timescale for the destruction of a typical refractory grain in the ISM is inferred to be about 4 × 108 yr for either a two-phase or a three-phase ISM. Most of the refractory material in the ISM (other than carbon) is injected by supernovae, not evolved stars; the net injection timescale is estimated as about 1.5 × 109 yr. Comparison of the destruction and injection timescales indicates that the fraction of grains injected by stars which survive in the ISM is only about 20%. Most of the refractory material in interstellar grains must, therefore, have accreted onto the grains in the ISM. Nonetheless, a significant fraction of dust formed in stars survives in the ISM and may be detectable in meteorites and interplanetary dust particles.
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van der Swaluw, Eric, Abraham Achterberg, and Yves A. Gallant. "The interaction of pulsar winds with old supernova remnants." International Astronomical Union Colloquium 177 (2000): 513–14. http://dx.doi.org/10.1017/s0252921100060450.
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Shock waves in young supernova remnants (SNR) are generally considered to be the places where production and acceleration of charged particles (relativistic electrons and cosmic rays) take place. Older remnants can be re-energised if an active pulsar catches up with the shell of the remnant (Shull, Fesen, & Saken 1989). In that case a pulsar-driven wind can inject energetic particles into the shell, resulting into a rejuvenation of the radio emission of the old remnant due to the presence of additional relativistic electrons.Radio observations of CTB80 (Angerhofer et al. 1981) and G5.4-1.2 (Frail & Kulkarni 1991) give evidence for the importance of the presence of an active pulsar close to the old shell of the remnants. In the first case the pulsar is believed to be inside the SNR. In the second case the pulsar is thought to have penetrated the shell of the SNR, and resides in the interstellar medium (ISM). We intend to investigate the physics which are connected with these kind of systems. One expects new effects resulting from the interaction of the three different shocks; the SNR shock, the bowshock bounding the pulsar wind nebula (PWN) and the (pulsar) wind termination shock. The dynamics of the system is described by a hydrodynamics code. We use the results from the hydrodynamics code to investigate the process of acceleration and transport of particles which are advected by the flow and diffuse with respect to the flow. We have applied the latter to a simple problem, the case of a spherically expanding SNR.
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Smith, R. Chris. "The UM/CTIO Magellanic Cloud Emission-line Survey." Publications of the Astronomical Society of Australia 15, no. 1 (1998): 163–64. http://dx.doi.org/10.1071/as98163.
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AbstractThe Magellanic Clouds are unique in providing us with sites to study the interstellar medium (ISM) and its components at all scales. To promote the pursuit of such studies, we have begun the Magellanic Cloud Emission-line Survey (MCELS), a deep imaging survey of both of these nearby galaxies in the emission of Hα, [S II], and [O III]. The emission-line images will be used in detailed optical and multiwavelength studies of H II regions, supernova remnants, planetary nebulae, superbubbles, and supergiant shells. Together with parallel surveys at other wavelengths, this survey will provide the foundation upon which to build a deeper understanding of the ISM in the Clouds and other galaxies, from small scales (∼1 pc) all the way up to global scales.
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Höflich, Peter A., Dietrich Baade, Alexei M. Khokhlov, Lifan Wang, and J. Craig Wheeler. "Aspherical supernova explosions." Symposium - International Astronomical Union 212 (2003): 387–94. http://dx.doi.org/10.1017/s0074180900212473.
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Core collapse supernovae (SN) are the final stages of stellar evolution in massive stars during which the central region collapses, forms a neutron star (NS), and the outer layers are ejected. Recent explosion scenarios assumed that the ejection is due to energy deposition by neutrinos into the envelope, but detailed models do not produce powerful explosions. There is new and mounting evidence for an asphericity and, in particular, for axial symmetry in several supernovae which may be hard to reconcile within the spherical picture. This evidence includes the observed high polarization and its variation with time, pulsar kicks, high velocity iron-group and intermediate-mass elements material observed in remnants, direct observations of the debris of SN 1987A, etc. Some of the new evidence is discussed in more detail. To be in agreement with the observations, any successful mechanism must invoke some sort of axial symmetry for the explosion. We consider jet-induced/dominated explosions of core collapse supernovae. Our study is based on detailed 3-d hydrodynamical and radiation transport models. We find that the observations can be explained by low velocity, massive jets which stall well within the SN envelope. Such outflows may be produced by MHD-mechanisms, convective dominated accretion disks on the central object or asymmetric neutrino emissions. Asymmetric density/chemical distributions and, for SN 2002ap, off-center energy depositions have been identified as crucial for the interpretation of the polarization.
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Hanasz, M., D. Woltanski, and K. Kowalik. "Interstellar and intergalactic dynamos." Proceedings of the International Astronomical Union 8, S294 (August 2012): 225–36. http://dx.doi.org/10.1017/s1743921313002573.
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AbstractWe review recent developments of amplification models of galactic and intergalactic magnetic field. The most popular scenarios involve variety of physical mechanisms, including turbulence generation on a wide range of physical scales, effects of supernovae, buoyancy as well as the magnetorotational instability. Other models rely on galaxy interaction, which generate galactic and intergalactic magnetic fields during galaxy mergers. We present also global galactic-scale numerical models of the Cosmic Ray (CR) driven dynamo, which was originally proposed by Parker (1992). We conduct a series of direct CR+MHD numerical simulations of the dynamics of the interstellar medium (ISM), composed of gas, magnetic fields and CR components. We take into account CRs accelerated in randomly distributed supernova (SN) remnants, and assume that SNe deposit small-scale, randomly oriented, dipolar magnetic fields into the ISM. The amplification timescale of the large-scale magnetic field resulting from the CR-driven dynamo is comparable to the galactic rotation period. The process efficiently converts small-scale magnetic fields of SN-remnants into galactic-scale magnetic fields. The resulting magnetic field structure resembles the X-shaped magnetic fields observed in edge-on galaxies.
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Chris Smith, R. "The UM/CTIO Magellanic Cloud Emission-line Survey." Symposium - International Astronomical Union 190 (1999): 28–31. http://dx.doi.org/10.1017/s0074180900117346.
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The Magellanic Clouds are unique in providing sites to study the interstellar medium (ISM) and its components at all scales. To promote the pursuit of such studies, we have begun the Magellanic Cloud Emission-line Survey (MCELS), a deep imaging survey of both of these nearby galaxies in the emission of Hα, [S II], and [O III]. The emission-line images will be used in detailed optical and multiwavelength studies of H II regions, supernova remnants, planetary nebulae, superbubbles, and supergiant shells. Together with parallel surveys at other wavelengths, this survey will provide the foundation upon which to build a deeper understanding of the ISM in the Clouds and other galaxies, from small scales (~1 pc) all the way up to global scales. We present a sample of recent and current work using the MCELS dataset.
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Cassidy, Andrew, Alexander Rosu-Finsen, Jérôme Lasne, Martin R. S. McCoustra, and David Field. "Acceleration of ion recombination reaction rates in cold dark clouds through spontaneous polarization charge on CO ice mantles." Proceedings of the International Astronomical Union 15, S350 (April 2019): 390–91. http://dx.doi.org/10.1017/s1743921319009281.
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AbstractWe propose a role for CO ice mantles in ion recombination reactions, and demonstrate how the subsequent fall in the degree of gas phase ionization decreases the time required for cloud collapse under gravity by a factor of 5-6. Experimental results demonstrate that CO films prepared at cryo-temperatures spontaneously harbour electric fields immediately upon growth. Using what is known from observations about prestellar cloud conditions in the ISM, we explain how this phenomenon can lead to an acceleration in ion recombination reaction rates. The result is a pathway for cloud collapse to occur before cloud disruption by supernova remnants.
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Winkler, P. Frank, Yasser Rathore, and R. Chris Smith. "A Digital Emission-Line Survey of the Small Magellanic Cloud." Symposium - International Astronomical Union 190 (1999): 97–98. http://dx.doi.org/10.1017/s0074180900117462.
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We present results on the SMC from the first full season of the Michigan/CTIO Magellanic Cloud Emission-Line Survey, being carried out from CTIO. Images are being obtained in Hα, [S II] λλ 6717, 6731, and [O III] λ 5007, plus red and green continuum bands for star subtraction. Data from the 1996–97 season have been assembled into large mosaic images which reveal the rich variety of nebulosity in the SMC in unprecedented detail. These are providing definitive samples of the active, occasionally violent, ISM on scales including superbubbles, wind-blown bubbles, supernova remnants, H II regions, and planetary nebulae.
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Feigelson, Eric D. "Do neutron stars produce jets?" Canadian Journal of Physics 64, no. 4 (April 1, 1986): 474–78. http://dx.doi.org/10.1139/p86-087.
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The evidence for jets emanating from neutron stars is reviewed. Isolated radio pulsars do not appear to produce collimated outflows. A few supernova remnants, notably the Crab nebula, exhibit jetlike protrusions at their outer boundaries. These are probably "blowouts" of the plasma in the remnant rather than true jets from a neutron star. However, several cases of degenerate stars in X-ray binary systems do make jets. SS433 has twin precessing jets moving outward at v ~ 0.26c, and Sco X-1 has radio lobes with v ~ 0.0001c. Cyg X-3 appears to eject synchrotron plasmoids at high velocities. Other X-ray binaries associated with variable radio sources are discussed; some are interesting candidates for collimated outflow. G109.1-1.0 is an X-ray binary in a supernova remnant that may have radio or X-ray jets. It is not clear in all these cases, however, that the compact object is a neutron star and not a black hole or white dwarf.A tentative conclusion is reached that isolated neutron stars do not produce jets, but degenerate stars in accreting binary systems can. This suggests that the presence of an accretion disk, rather than the characteristics of an isolated pulsar's dipole magnetosphere, is critical in making collimated outflows.
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Green, D. A. "The Spectral Turnover of the “Filled-Center” Supernova Remnant 3C 58: Implications for When Acceleration Occurs." International Astronomical Union Colloquium 142 (1994): 817–21. http://dx.doi.org/10.1017/s0252921100078143.
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AbstractIRASobservations the “filled-center” supernova remnant 3C 58 are used to derived upper limits of 0.4, 0.4, 0.8, and 1.5 Jy for its infrared flux density at 12, 25, 60, and 100 μm, respectively. These values imply a break in the spectrum of 3C58 above a few tens of gigahertz—two orders of magnitude below the break in the spectrum of the Crab Nebula—with a change of spectral index across the break for 3C 58 of more than 0.5. This is similar to previous results for another “filled-center” remnant, G74.9+1.2, from radio observations alone. This implies that their emission isnotdominated by a constant injection rate of particles with a power-law distribution. Either the break is due to synchrotron losses in the past, with little particle injection in recent times or it is intrinsic to the acceleration mechanism at work (presumably from a central neutron star).Subject headings: acceleration of particles — ISM: individual (3C 58) — radiation mechanisms: nonthermal — supernova remnants
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Wang, Qingde, and David J. Helfand. "An X-ray survey of OB associations in the Large Magellanic Cloud." Symposium - International Astronomical Union 148 (1991): 224–25. http://dx.doi.org/10.1017/s0074180900200466.
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Based on Einstein IPC data, we have completed a census of X-ray emission from and around OB associations in the LMC. In addition to an apparent correlation of young, X-ray bright supernova remnants with recent star formation regions, we detect diffuse X-ray emission from over two dozen other associations; luminosities in the 0.16–3.5 keV band range from ˜ 3 × 1034 (the detection threshold) to ˜ 1036erg s−1. The mean X-ray luminosity of the ˜ 50 undetected associations is ˜ 1034erg s−1 and the emission from all associations contributes ˜ 4% to the total diffuse X-ray emission from the galaxy. Implications of this survey for ISM bubble evolution is discussed.
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Kannan, Rahul, Federico Marinacci, Christine M. Simpson, Simon C. O. Glover, and Lars Hernquist. "Efficacy of early stellar feedback in low gas surface density environments." Monthly Notices of the Royal Astronomical Society 491, no. 2 (November 4, 2019): 2088–103. http://dx.doi.org/10.1093/mnras/stz3078.
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ABSTRACT We present a suite of high-resolution radiation hydrodynamic simulations of a small patch (1 kpc2) of the interstellar medium (ISM) performed with arepo-rt, with the aim to quantify the efficacy of various feedback processes like supernova (SN) explosions, photoheating, and radiation pressure in low gas surface density galaxies (Σgas ≃ 10 M⊙ pc−2). We show that radiative feedback decrease the star formation rate and therefore the total stellar mass formed by a factor of approximately two. This increases the gas depletion time-scale and brings the simulated Kennicutt–Schmidt relation closer to the observational estimates. Radiation feedback coupled with SN is more efficient at driving outflows with the mass and energy loading increasing by a factor of ∼10. This increase is mainly driven by the additional entrainment of medium-density (10−2 cm−3 ≤ n < 1 cm−3) warm (300 K ≤ T < 8000 K) material. Therefore, including radiative feedback tends to launch colder, denser, and more mass- and energy-loaded outflows. This is because photoheating of the high-density gas around a newly formed star overpressurizes the region, causing it to expand. This reduces the ambient density in which the SN explode by a factor of 10–100 which in turn increases their momentum output by a factor of ∼1.5–2.5. Finally, we note that in these low gas surface density environments, radiative feedback primarily impact the ISM via photoheating and radiation pressure has only a minimal role in regulating star formation.
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Priestley, F. D., H. Chawner, M. Matsuura, I. De Looze, M. J. Barlow, and H. L. Gomez. "Revisiting the dust destruction efficiency of supernovae." Monthly Notices of the Royal Astronomical Society 500, no. 2 (November 5, 2020): 2543–53. http://dx.doi.org/10.1093/mnras/staa3445.
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ABSTRACT 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.
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Derlopa, S., P. Boumis, A. Chiotellis, W. Steffen, and S. Akras. "First 3D morpho-kinematic model of supernova remnants. The case of VRO 42.05.01 (G166.0+4.3)." Monthly Notices of the Royal Astronomical Society 499, no. 4 (August 14, 2020): 5410–15. http://dx.doi.org/10.1093/mnras/staa2336.
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ABSTRACT We present the first three-dimensional (3D) morpho-kinematic (MK) model of a supernova remnant (SNR), using as a case study the Galactic SNR VRO 42.05.01. We employed the astrophysical code SHAPE in which wide field imaging and high-resolution spectroscopic data were utilized, to reconstruct its 3D morphology and kinematics. We found that the remnant consists of three basic distinctive components that we call: a ‘shell’, a ‘wing’, and a ‘hat’. With respect to their kinematical behaviour, we found that the ‘wing’ and the ‘shell’ have similar expansion velocities (Vexp = 115 ± 5 km s−1). The ‘hat’ presents the lowest expansion velocity of the remnant (Vexp = 90 ± 20 km s−1), while the upper part of the ‘shell’ presents the highest velocity with respect to the rest of the remnant (Vexp = 155 ± 15 km s−1). Furthermore, the whole nebula has an inclination of ∼3°–5° with respect to the plane of the sky and a systemic velocity of Vsys = −17 ± 3 km s−1. We discuss the interpretation of our model results regarding the origin and evolution of the SNR and we suggest that VRO 42.05.01 had an interaction history with an inhomogeneous ambient medium most likely shaped by the mass outflows of its progenitor star.
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Kim, Jeong-Gyu, Munan Gong, Chang-Goo Kim, and Eve C. Ostriker. "Photochemistry and Heating/Cooling of the Multiphase Interstellar Medium with UV Radiative Transfer for Magnetohydrodynamic Simulations." Astrophysical Journal Supplement Series 264, no. 1 (December 19, 2022): 10. http://dx.doi.org/10.3847/1538-4365/ac9b1d.
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Abstract We present an efficient heating/cooling method coupled with chemistry and UV radiative transfer that can be applied to numerical simulations of the interstellar medium (ISM). We follow the time-dependent evolution of hydrogen species (H2, H, H+), assume carbon/oxygen species (C, C+, CO, O, and O+) are in formation–destruction balance given the nonsteady hydrogen abundances, and include essential heating/cooling processes needed to capture the thermodynamics of all ISM phases. UV radiation from discrete point sources and the diffuse background is followed through adaptive ray tracing and a six-ray approximation, respectively, allowing for H2 self-shielding; cosmic-ray heating and ionization are also included. To validate our methods and demonstrate their application for a range of density, metallicity, and radiation fields, we conduct a series of tests, including the equilibrium curves of thermal pressure versus density, the chemical and thermal structure in photodissociation regions, H i-to-H2 transitions, and the expansion of H ii regions and radiative supernova remnants. Careful treatment of photochemistry and cosmic-ray ionization is essential for many aspects of ISM physics, including identifying the thermal pressure at which cold and warm neutral phases coexist. We caution that many current heating and cooling treatments used in galaxy formation simulations do not reproduce the correct thermal pressure and ionization fraction in the neutral ISM. Our new model is implemented in the MHD code Athena and incorporated in the TIGRESS simulation framework, for use in studying the star-forming ISM in a wide range of environments.
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Cosentino, G., I. Jiménez-Serra, J. C. Tan, J. D. Henshaw, A. T. Barnes, C.-Y. Law, S. Zeng, et al. "Negative and positive feedback from a supernova remnant with SHREC: a detailed study of the shocked gas in IC443." Monthly Notices of the Royal Astronomical Society 511, no. 1 (January 12, 2022): 953–63. http://dx.doi.org/10.1093/mnras/stac070.
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ABSTRACT Supernova remnants (SNRs) contribute to regulate the star formation efficiency and evolution of galaxies. As they expand into the interstellar medium (ISM), they transfer vast amounts of energy and momentum that displace, compress, and heat the surrounding material. Despite the extensive work in galaxy evolution models, it remains to be observationally validated to what extent the molecular ISM is affected by the interaction with SNRs. We use the first results of the ESO–ARO Public Spectroscopic Survey SHREC to investigate the shock interaction between the SNR IC443 and the nearby molecular clump G. We use high-sensitivity SiO(2-1) and H13CO+(1-0) maps obtained by SHREC together with SiO(1-0) observations obtained with the 40-m telescope at the Yebes Observatory. We find that the bulk of the SiO emission is arising from the ongoing shock interaction between IC443 and clump G. The shocked gas shows a well-ordered kinematic structure, with velocities blue-shifted with respect to the central velocity of the SNR, similar to what observed towards other SNR–cloud interaction sites. The shock compression enhances the molecular gas density, n(H2), up to >105 cm−3, a factor of >10 higher than the ambient gas density and similar to values required to ignite star formation. Finally, we estimate that up to 50 per cent of the momentum injected by IC443 is transferred to the interacting molecular material. Therefore, the molecular ISM may represent an important momentum carrier in sites of SNR–cloud interactions.
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Blandford, R. D. "The Phenomena of High Energy Astrophysics." Symposium - International Astronomical Union 214 (2003): 3–20. http://dx.doi.org/10.1017/s0074180900194124.
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A brief summary of some highlights in the study of high energy astrophysical sources over the past decade is presented. It is argued that the great progress that has been made derives largely from the application of new technology to observation throughout all of the electromagnetic and other spectra and that, on this basis, the next decade should be even more exciting. However, it is imperative to observe cosmic sources throughout these spectra in order to obtain a full understanding of their properties. In addition, it is necessary to learn the universal laws that govern the macroscopic and the microscopic behavior of cosmic plasma over a great range of physical conditions by combining observations of different classes of source. These two injunctions are illustrated by discussions of cosmology, hot gas, supernova remnants and explosions, neutron stars, black holes and ultrarelativistic outflows. New interpreations of the acceleration of Galactic cosmic rays, the cooling of hot gas in rich clusters and the nature of ultrarelativistic outflows are outlined. The new frontiers of VHE γ-ray astronomy, low frequency radio astronomy, neutrino astronomy, UHE cosmic ray physics and gravitational wave astronomy are especially promising.
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Dufour, Reginald J., Brent A. Buckalew, Patrick L. Shopbell, and Donald K. Walter. "The chaotic ISM of the post(?)-starburst galaxy NGC 1569." Symposium - International Astronomical Union 212 (2003): 549–50. http://dx.doi.org/10.1017/s0074180900212801.
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We present the results and analysis of HST-wfpc2 imagery of the starburst galaxy NGC 1569 (d = 2.2 Mpc), which permit unprecedented resolution (~ 1pc) of the ionized gas and stellar population. The primary data in our analysis consists of images taken through narrow-band filters isolating Hβ, Hα, [O iii]λ5007, and [S ii]λλ6717+30, as part of go Program 8133. A variety of color-coded and grey-scaled maps of the morphology, ionization structure, and dust distribution are presented. Unsharp masks of the Hα images show a very chaotic structure for the ionized gas, with numerous filaments and arc-like bright rim features across the entire galaxy, but without significant large-scale ionization variations. Variations in the ionization and line-of-sight reddening occur on smaller scales (~ 10 – 50 pc), with numerous low-ionization semi-stellar knots seen throughout the main body of the galaxy, even within the ‘hole’ in the ionized gas distribution around the central super star clusters previously noted from H i maps. Several of these features have strong [S ii] emission indicative of being supernova remnants. We combine these data with archival wide-band HST-wfpc2 imagery to quantitatively evaluate the source(s) of the (largely photo-) ionized gas.