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we present nuv, fuv and soft x-ray (0.3-10 kev) imaging and x-ray spectroscopic studies of two, 30' diameter, adjacent, segments of the x-ray, uv- and optically bright, vela-d "bullet" of the vela supernova remnant (snr), using the astrosat/uvit (with f169m, f172m filters) and astrosat/sxt instruments. the x-ray bright... | narrow band uv imaging and soft x-ray spectral studies of vela-d with astrosat. |
we present the results of our x-ray ejecta kinematic study of kepler's and tycho's supernova remnants (snrs) based on our chandra hetg observations, and of our far-infrared (fir) spectroscopic study of unpublished archival snr data from the infrared space observatory (iso). we report our measurements of the bulk radial... | x-ray kinematics and infrared spectroscopic studies of supernova remnants |
the acceleration of non-thermal particles in collisionless shocks, especially in supernova remnant shocks, is a long standing problem for revealing the origin of galactic cosmic-rays. in the most relied scenario, the galactic cosmic-rays originate in the diffusive shock acceleration mechanism, and the pressure of accel... | h alpha polarimetry as a powerful diagnostics of cosmic-ray modified shock |
x-ray observations of young supernova remnants (snrs) provide strong evidence for shock acceleration of particles to extremely high energies. x-ray synchrotron emission traces the sites of particle acceleration and constrains the timescales and maximum energies for the underlying process. combined with information glea... | probing particle acceleration in tycho's snr with x-ray polarization |
despite the importance of massive stars and star clusters for the energy content, stellar population and evolution of galaxies, the mechanism that ignites their formation in molecular clouds is still poorly addressed. infrared dark clouds (irdcs) are the likely precursors of massive stars. it has been suggested that ir... | the "shocking" interaction between supernova remnants and molecular clouds |
the iras 4a system is part of the southern filament of the perseus ngc 1333 molecular cloud. as most of the star forming regions, ngc 1333 is known to be heavily shaped by external triggers, such as shock fronts around ob stars or supernovae remnants, cloud-cloud collisions, and instabilities. recently, it has been hyp... | shocks in the surroundings of the ngc 1333 iras 4 system |
kepler's supernova remnant (snr) is believed to result from a type ia supernova, but to be interacting with dense circumstellar material (csm), which makes its progenitor system a mystery. using the chandra acis-s 741 ks effective exposure data and an advanced adaptive binning algorithm, we analyse the spectra from tes... | spatially resolved x-ray spectroscopy of kepler's supernova remnant: distinct properties of the circumstellar medium and the ejecta |
supernovae (sne) are known producers of dust grains based on infrared emission from young supernova remnants. however, in such remnants, the reverse shock that forms as the ejecta interact with the surrounding interstellar medium (ism) has not yet propagated back to the explosion center and the newly formed grains and ... | supernova grain evolution for explosions in pre-existing bubbles |
extreme astrophysical objects such as relativistic jets and supernova remnants exhibit nonthermal radiative spectra highlighting the presence and the generation of suprathermal particle distributions - i . e . cosmic rays. the maximum energy reached through diffusive shock acceleration in such environments is directly ... | nonlinear evolution of cosmic-ray driven instabilities |
several young supernova remnants exhibit thin x-ray bright rims of synchrotron radiation at their forward shocks. thin rims have been taken to indicate that shock-accelerated electrons rapidly cool downstream of the shock, requiring strong magnetic field amplification. but, magnetic field damping immediately behind the... | synchrotron x-ray rims in tycho's supernova remnant are energy dependent |
g23.33-0.30 is a 600 msun infrared dark molecular filament that exhibits large turbulent line widths and four rare nh3(3,3) masers, which are excited by a large-scale shock impacting the filament. g23.33-0.30 also displays a velocity gradient along its length, a velocity discontinuity across its width, shock-tracing si... | the interaction between the supernova remnant w41 and the filamentary infrared dark cloud g23.33-0.30 |
studies of populations of supernova remnants (snrs) in different galaxies provide a more representative picture of their importance for feedback and metal enrichment in a wide variety of galactic environments. we present our results on the snrs populations in a sample of nearby spiral galaxies, based on deep narrow-ban... | study of extragalactic supernova remnants |
sprite, the first nasa-funded 12u cubesat for astrophysics science, will use an ultraviolet light spectrograph with a photon-counting microchannel plate detector to provide spatial and spectral data on the light observed from low-redshift galaxies, active galactic nuclei, and shocked emission features of supernova remn... | progress on the design, implementation, and experimental evaluation of the electronics for the sprite cubesat |
sub-millimetre observations of galaxies at redshift z > 6 have revealed dust masses of up to 108 solar masses. as such systems are too young for significant dust enrichment by asymptotic giant branch stars to have occurred, core-collapse supernovae (ccsne) have been suggested as possible alternative dust producers. ... | hydrodynamic simulations of supernova remnants: dust destruction by the reverse shock |
linearly polarized balmer line emissions from supernova remnant shocks are studied taking into account the energy loss of the shock owing to the production of cosmic-rays. the polarization degree depends on the downstream temperature and the velocity difference between upstream and downstream regions. the former is der... | polarized balmer line emission from snr shocks: on the effects of cosmic-ray acceleration |
supernova remnants (snrs) drive large-scale shocks that locally enhance the density of the surrounding material. they also inject vast amounts of energy and momentum that largely perturb and disperse the interstellar medium (ism). the interplay between these two effects is considered paramount in regulating the star fo... | feedback from supernova remnants: triggering star formation in the ism |
a critical component to explaining the observation of cosmic ray acceleration at supernova remnants is the non-resonant bell's instability, where the relative drift between the thermal ions and the cosmic rays lead to the amplification of magnetic fields necessary to accelerate particles with diffusive shock accelerati... | understanding the breakdown of the bell instability in the limit of high cosmic ray current density |
we present a comprehensive x-ray spectroscopy and imaging study of supernova remnant w49b using archival xmm-newton observations. the overionization state of the shocked ejecta in w49b is clearly indicated by the radiative recombination continua of si xiv, s xv, and fe xxv, combined with the ly$\alpha$ lines of ca and ... | an xmm-newton x-ray view of supernova remnant w49b: revisiting its recombining plasmas and progenitor type |
supernova remnants are widely believed to be the sources responsible for the acceleration of galactic cosmic rays. over the last several years, observations made with the fermi gamma-ray space telescope have confirmed that cosmic-ray nuclei are indeed accelerated in some supernova remnants, including ic 443, which is a... | constraining the cosmic-ray acceleration efficiency in the supernova remnant ic 443 |
collisionless shocks in plasma are a common feature in astrophysical systems such as the earth's bow shock and supernova remnants. to improve our understanding of these fundamentally non-linear collisionless shocks, we probe the velocity distribution functions (vdfs) of these plasmas. recent laser experiments have recr... | reconstructing plasma velocity distribution functions using stochastic gradient descent |
in star-forming environments, shock-compressed magnetic fields occur in cloud-cloud collisions, in molecular clouds exposed to supernova remnants (snrs), and in photo-dissociation regions (pdrs). besides their dynamical role, they increase the cosmic ray flux above the galactic average, and the trapped particles contri... | signposts of shock-induced magnetic field compression in star-forming environments |
the most noticeable thing about mixed-morphology supernova remnant (mm snr) vro 42.05.01 is its shape, with a round shell of emission and a broad triangular wing that intersect in a sharp line. this puzzling shape has been attributed to the presence of an ambient medium with two densities: a dense medium in which the e... | the circumstellar and interstellar environment of vro 42.05.01. a peculiar mixed morphology snr |
the vela supernova remnant (snr) is an ideal laboratory for studying the physical processes associated with snr evolution in a highly inhomogeneous interstellar medium (ism). previous uv and optical absorption-line studies have revealed the remarkable nature of the highly disturbed interstellar gas interacting with the... | spatial and temporal variations in the physical conditions of clouds shocked by the vela supernova remnant |
magnetized collisionless (λmfp > > lshock) shocks are created throughout the universe including within super-nova remnants and the earth's atmosphere. when these shocks propagate into a magnetised background plasma where fields are aligned perpendicular to the flow velocity, density perturbations and voids can be... | effect of background magnetic fields on magnetised, collisionless shocks. |
supernovae are key drivers of the evolution of the interstellar medium of galaxies as they are main sources of heavy elements and kinetic energy. dense, fast-moving ejecta knots in supernova remnants (snrs) are prime sites for molecule and dust formation. whether dust is survived from the reverse shock is one of the un... | sofia far-infrared fifi-ls observations of co-rich knots in the supernova remnant cas a |
energetic particles, with energies much larger than thermal energies, are observed in most astrophysical environments, but a full understanding of the acceleration processes is still missing. here, we make a comparison of the observed acceleration rates at various astrophysical environments like solar flares, crab nebu... | comparing particle acceleration rates of different astrophysical environments |
we investigate the diffusive shock acceleration of particles with mass to charge ratio, a/q > 1. we introduce he- and c-like particles at solar abundances into 2d hybrid (kinetic ions/fluid electrons) simulations of non-relativistic collisionless shocks. we find that particles with large a/q ratios are preferentiall... | hybrid simulations of acceleration of heavy nuclei at non-relativistic shocks |
collisionless shocks in space and astrophysical plasmas are among the main candidates to explain the acceleration of particles to very high energies. direct evidence of shock acceleration is given by spacecraft in the heliosphere, but how the properties of accelerated particles, like the energy spectrum, intensity, and... | particle acceleration and transport at collisionless shocks: effects of superdiffusion deduced from data analysis and numerical simulations |
strong shocks in collisionless plasmas, such as supernovae shocks and shocks driven by coronal mass ejections, are known to be a primary source of energetic particles. in this talk, i will discuss recent observations of nonstationarity and ion acceleration processes at high mach number quasi-perpendicular shocks. resul... | magnetic reflection of heavy ions from high mach number quasi-perpendicular shocks: mms observations |
we investigate electron heating in collisionless, non-relativistic, perpendicular electron-ion shocks from first principles. we employ numerical, fully kinetic, two-dimensional particle-in-cell simulations to follow the shock formation until the downstream steady-state in electron-ion temperature ratio te /ti is reache... | non-adiabatic electron heating in supernova remnant shocks |
diffusive shock acceleration (dsa) is an efficient mechanism that produces power-law distributions of nonthermal particles and is responsible for the acceleration of galactic cosmic rays (crs) at the forward shocks of supernova remnants (snrs). however, observations of nonthermal snr emission imply cr energy distributi... | a revised theory of diffusive shock acceleration |
the mechanisms of explosion of different type supernovae (sne) are discussed. at least four mechanisms are under detailed inspection of scientific community for core-collapse sne. they are the instability of standing accreting shock front that results in the large scale 3-dimensional hydrodynamic flows, the phase trans... | mechanisms of supernova explosion: modern status |
energy injection by supernovae is believed to be one of the primary sources which powers the expansion of supershells. there is a qualitative difference between isolated supernovae (sne) and overlapping sne. for typical interstellar medium (ism) conditions an isolated supernova loses most of the injected mechanical ene... | dynamics of supernova driven superbubbles |
recent suzaku observations revealed the presence of recombining plasmas (rps), which have ionization temperatures higher than electron temperatures. w28 is a middle-aged snr located on the galactic ridge. sawada et al. (2012) discovered a rp in the central region of the snr. in the northeastern region, co emissions and... | spatially resolved spectroscopy of w28 with suzaku |
we have obtained high-angular resolution images of kepler's supernova remnant (snr), a type ia remnant, using the hubble space telescope (hst) at two epochs separated by 10 years. based on the proper motions of the faint balmer filaments that are due to fast shocks, we established a distance of 5.1 kpc to the remnant (... | dual epoch hst imaging of kepler's supernova remnant -bright knot variability and search for a possible sn progenitor companion |
there is a clear connection between the evolutionary properties of a massive star and the properties of the resultant supernova and supernova remnant. here we present new results where we have modeled 45,000 supernova remnants to ages of 5000 years, and synthesized spectra for both shocked circumstellar material and sh... | classifying supernova remnant spectra with machine learning |
young supernova remnants (snrs) are among the most important sources of non-thermal x-rays in the sky and the likely sources of most of galactic cosmic rays. however, there are still many open questions on the physical conditions at their shock fronts, such as the magnetic field orientation and turbulence level. the x-... | first result of the ixpe observations of the supernova remnants cas a, tycho, and sn 1006 |
the james webb space telescope (jwst) will enable near- and mid-infrared studies of supernovae (sn) and supernova remnants (snr) in the milky way and galaxies throughout the local universe and to high redshift. jwst's instrumentation provides imaging, coronography, and spectroscopy (r<3000) over the wavelength range... | observing supernovae and supernova remnants with jwst |
the newly discovered g306.3-0.9 is a young galactic supernova remnant (snr). chandra observation indicates a complex morphology dominated by a bright shock with an age of about 2500 yr. in this study, we investigate abundances and ionization state of plasma in snr using archival suzaku data. we also discuss the progeni... | an x- and gamma-ray study of the young supernova remnant g306.3-0.9 |
galactic cosmic rays are believed to be accelerated at supernova remnant (snr) shocks. in the hadronic scenario the tev gamma-ray emission from snrs originates from decaying pions that are produced in collisions of the interstellar gas and cosmic rays. using cosmic ray magnetohydrodynamic simulations performed with the... | constraining the coherence scale of the interstellar magnetic field using tev gamma-ray observations of supernova remnants |
one of the most important challenges for the largely accepted idea that galactic crs are accelerated in snr shocks is the maximum energy at which particles can be accelerated. the resonant streaming instability, long invoked for magnetic field amplification at shocks, can not provide sufficiently high fields and effici... | on the cosmic ray spectrum from type ii supernovae |
shocks are ubiquitous in the interstellar medium of galaxies, where they contribute to the energetic balance and to the cycle of matter, and where they are thought to be the primary sites for cosmic rays acceleration. most of the time: in jets and outflows, supernova remnants, or colliding flows, they are linked with s... | interstellar shock studies: the sofia/great contribution |
galactic cosmic rays (crs) are accelerated at the forward shocks of supernova remnants (snrs) via diffusive shock acceleration (dsa), an efficient acceleration mechanism that predicts power-law energy distributions of crs. however, observations of nonthermal snr emission imply cr energy distributions that are generally... | steep cosmic ray spectra in supernova remnants |
in the last years, with the increasing number of discovered γ-ray sources, important efforts have been dedicated to establish the origin of this high-energy emission using observations in other spectral bands. supernova remnants (snrs) have been proposed as possible generators of γ-rays in our galaxy, among other astro... | the interstellar medium towards three supernova remnants |
hydrodynamic instability experiments are being developed and carried out on the national ignition facility (nif) laser at llnl through the nif discovery science (basic science) program and the high energy density (hed) science program. the motivations are many, including supernova explosion dynamics; supernova remnant ... | hydrodynamic instabilities and mixing in high energy density settings on nif |
young supernova remnants (snrs) can have a reservoir of internal, cold stellar ejecta that have not yet been heated by the reverse shock. these can be traced in few ways: through the decay of radioactive elements (if the remnant is still very young), through infrared line emission (which can be faint), or through low-f... | the unshocked ejecta in cas a and tycho through low-frequency radio absorption |
we present the first results from a deep (900 ks) observation of the large magallenic cloud supernova remnant n132d with the chandra x-ray observatory. n132d is an o-rich supernova remnant (snr) of a 15-25 mθ progenitor and is the most x-ray luminous snr in the local group (lx ~ 1038 ergs/s [0.3-10.0 kev]). the chandra... | chandra legacy observation of lmc n132d: first results |
supernova remnants (snrs) in the local group offer unique insights into the origin of different types of supernovae. however, the intrinsic diversity and environment-driven evolution of snrs require the use of statistical methods to model snr populations in the context of their host galaxy. we introduce a semi-analytic... | statistical modelling of supernova remnant populations in the local group |
the study of astrophysical phenomena such as supernovae, accretion disks, galaxy formation, and large-scale structure formation requires computational modeling of, at a minimum, hydrodynamics and gravity. developing numerical methods appropriate for these kinds of problems requires a number of properties: shock-capturi... | crksph: a new meshfree hydrodynamics method with applications to astrophysics |
gamma ray emission from several middle aged supernova remnants (snrs) has been detected in space-based gev observations and ground-based tev observations. the characteristic pion-decay signature identified in spectra of the remnants ic443 and w44 provides strong evidence for cosmic ray (cr) proton acceleration in snrs.... | gamma ray emission from middle aged supernova remnants interacting with molecular clouds |
sn 1996cr ranks among the closest and brightest supernovae (sne) detected, and exhibits a unique spectral evolution compared to typical type-ii sne. the emission is attributed to the ejecta propagating through increasingly dense circumstellar material, probably a circumstellar shell leftover from the past evolution of ... | witnessing the birth of a supernova remnant |
x-ray observations are one of the strong tools to study acceleration sites of cosmic rays, not only with synchrotron emission but also with thermal emission from heated plasma. thermal x-rays with emission lines give us plenty of information on temperature, density, plasma time scale and so on, for heated interstellar ... | x-ray observations of supernova remnants - environment study of acceleration sites |
as recognized prominently by the apra program, interpretation of nasa astrophysical mission observations requires significant products of laboratory astrophysics, for example, spectral lines and transition probabilities, electron-, proton-, or heavy-particle collision data. availability of these data underpin robust an... | computational laboratory astrophysics to enable transport modeling of protons and hydrogen in stellar winds, the ism, and other astrophysical environments |
the proximity of sn 1987a and the wealth of observations collected at all wavelenght bands since its outburst allow us to study in details the evolution of a supernova remnant (snr) from the immediate aftermath of the sn explosion till its expansion through the highly inhomogeneous circumstellar medium (csm). we invest... | three-dimensional hydrodynamic modeling of sn 1987a from the supernova explosion till the athena era |
supernova remnant (snr) ctb 37b, morphologically characterized by an incomplete radio shell, is spatially coincident with the extended tev source hess j1713-381 and harbours a magnetar, cxou j171405.7-381031. it is still debating whether the gamma-ray emission originates from the decay of neutral pions produced by prot... | mopra co-line observation towards snr ctb37b |
tycho's supernova remnant (snr) is the expanding remnant from sn 1572, the penultimate galactic supernova to have been recorded by contemporary observers. its optical light is almost exclusively faint hydrogen balmer emission around the periphery of the snr, produced where fast nonradiative shocks encounter partly neut... | expansion of the optical remnant from tycho’s supernova |
we present an analysis of a suzaku observation made of the galactic supernova remnant (snr) 3c 396 (g39.2-0.3). this snr was detected by prior spitzer irac and mips surveys of galactic snrs and the measured infrared colors for 3c 396 are consistent with emission from shocked ionized gas. a chandra observation suggests ... | a suzaku observation of the galactic supernova remnant 3c 396 (g39.2-0.3) |
radiative shocks are strong shocks which are characterized by a plasma at high temperatures emitting an important fraction of its energy as radiation. radiative shocks are found in many astrophysical systems, including stellar accretion shocks, supernovae remnants, jet driven shocks, etc. in the case of stellar accreti... | laboratory experiments on radiative shocks relevant to stellar accretion |
sn 1987a is the great supernova of the hst era. it is the only case where we have detailed knowledge of the pre-existing structure in the circumstellar gas. it is the only case where we can observe the details of a transition from supernova to supernova remnant. an unbroken string of observations is the essential tool ... | saints: images of sn 1987a |
collisionless shocks of supernova remnants (snr) are thought to be the acceleration sites of high-energy cosmic rays (crs). efficient particle production in the diffusive shock acceleration process requires turbulent amplified magnetic fields in the shock's precursor. here we report results of new particle-in-cell (pic... | nonlinear evolution of the nonresonant instability upstream of a young supernova remnant shock |
shock formation from high-mach number plasma flows is observed in many astrophysical objects such as supernova remnants and gamma ray bursts. these are collisionless shocks as the ion-ion collision mean free path is much larger than the system size. it is believed that seed magnetic fields can be generated on a cosmolo... | laboratory astrophysical collisionless shock experiments with interpenetrating plasma flows on omega and nif |
the nature and origin of interstellar dust are still not well understood. models of dust evolution in galaxies have shown that the dust destruction rate by sn shocks in the interstellar medium (ism) exceeds the dust injection rates by stellar sources and supernovae (sne), and that these source cannot account for the du... | the origin of dust in the magellanic clouds |
in a radio polarization study of the supernova remnant (snr) of sn1006, we found evidence for variable faraday rotation toward the fr-i radio galaxy eso 328-13. the background source lies on the eastern edge of the snr, and its jets are aligned east to west. the core and western lobe lie within the remnant's interior, ... | constraining the post-shock magnetic field strength of sn1006 from the rotation measure of radio galaxy eso 328-13 |
charge exchange, the semi-resonant transfer of an electron from a neutral atom to an excited state in an energetic ion, can occur in plasmas where energetic ions are incident on a cold, at least partially neutral gas. supernova remnants, especially in the immediate shock region, provide conditions conducive to charge e... | high-resolution studies of charge exchange in supernova remnants with magellan, xmm-newton, and micro-x |
we present a summary of far-infrared imaging observations of the inner 40 pc of the galactic center addressing the dense, dusty torus around sgr a*, massive star formation, and dust production around massive stars and in the sgr a east supernova remnant. observations of warm dust emission were performed using the faint... | revealing the galactic center in the far-infrared with sofia/forcast |
the amplification of magnetic fields is a central ingredient in understanding particle acceleration in supernova remnant shocks. i will present results from multi-dimensional particle-in-cell simulations of shock formation and particle acceleration for different magnetization levels. these first principles simulations,... | magnetic field amplification and particle acceleration in high mach number shocks |
in congiu et al. (submitted), we compile the largest catalog of classified ionized nebulae available in the literature from the data of the phangs-muse survey. the catalog contains 40000 nebulae classified using a specifically developed model-comparison-based classification algorithm. using this catalog we are able to ... | classification of ionized nebulae in the phangs-muse sample: a bayesian approach |
we propose to use wfc3 narrowband imaging to obtain hst 2nd epoch h-alpha, [s ii] and [o iii] images of an isolated shock-cloud interaction in the cygnus loop that was previously observed in 1994 using wfpc2. the two sets of images separated by over 30 years will allow us to characterize the evolution of the shocked ga... | evolution of an isolated shock-cloud interaction along the southeastern boundary of the cygnus loop supernova remnant |
charged particles accelerated by interplanetary shocks can escape from the shock without returning to it. however, the simplest version of the model of diffusive shock acceleration (dsa) does not include an energy-dependent escape from the foreshock region. we present a model for interplanetary shock acceleration that ... | model for the energetic particles spectrum at interplanetary shocks resulting from acceleration and escape sourced by a preexisting population with power law energy spectrum |
we will present optical images and spectra of a few stars that are projected within the cygnus loop supernova remnant's boundaries that show evidence for aninteraction of recent stellar mass loss material with the remnant's forward shock. shock interactions are visible in the spectra and morphology of these star's mass... | a new distance determination to the cygnus loop |
the galacting supernova remnant g349.7+0.2 is interacting with amolecular cloud. its gamma-ray emission has been revealed with hessand fermi-lat and is interpreted as the result of a pion decay processdue to accelerated protons impacting with the cloud. previous chandraand suzaku observations have shown that the x-ray ... | studying the gamma-ray emitting supernova remnant g349.7+0.2 |
energy-transport effects can alter the structure that develops as a supernova evolves into a supernova remnant. the rayleigh taylor instability is thought to produce structure at the interface between the stellar ejecta and the circumstellar matter, based on simple models and hydrodynamic simulations. simulations predi... | how high energy fluxes may affect rayleigh-taylor instability growth in young supernova remnants |
we have developed an inversion method for determination of the characteristics of the acceleration mechanism directly and non-parametrically from observations, in contrast to the usual forward fitting of parametric model variables to observations. this is done in the frame work of the so-called leaky box model of accel... | non parametric determination of acceleration characteristics in supernova shocks based on spectra of cosmic rays and remnant radiation |
using integral field data we extract the optical spectra of shocked interstellar clouds in kepler's supernova remnant located in the inner regions of our galaxy, as well as in the large magellanic cloud, the small magellanic cloud, ngc 6822, and ic 1613. using self-consistent shock modeling, we make a new determination... | calibrating interstellar abundances using snr radiative shocks - *in his memory, who passed away on december 22, 2018 - by i. seitenzahl |
the origin of magnetic fields in high-redshift and present-day galaxies is a long-standing problem. in this talk, we present a model for the seeding and evolution of magnetic fields in protogalaxies. supernova (sn) explosions during the assembly of a protogalaxy self-consistently provide magnetic seed fields, which are... | how do galaxies get their magnetic fields? |
momentum feedback from supernova remnants (snrs) is a key ingredient in numerical simulations of galaxy formation. however, the mass and spatial scales of snrs are much smaller than/barely resolved in such simulations, making a self-consistent prediction of feedback unfeasible. the alternative has been "sub-grid" model... | observational tests of momentum feedback by supernova remnants in m31 |
g132.7+1.3 is one of the most extended supernova remnants is our galaxy. in this work we explore its optical emission with hα + [nii ], [sii ] and [oiii ] imaging, which we compare with its emission in other wavelengths, and spectral data for its brightest filaments. we find that its optical structure matches these of ... | deep optical study of the supernova remnant g132.7+1.3 |
cassiopeia a, a well-observed young core-collapse supernova remnant (snr), is considered as one of the best candidates for studying very high-energy particle acceleration up to pev via the diffusive shock mechanism. recently, magic observations revealed a gamma-ray spectral cutoff at 3.5 tev, suggesting that if the tev... | is supernova remnant cassiopeia a a pevatron? |
the amount of ejecta dust which can survive into the interstellar medium (ism) is a key factor in the ability of core-collapse sne to resolve the dust budget crisis in high-redshift galaxies. we present physical models of the dust emission from two nearby supernova remnants, cassiopeia a (cas a) and the crab nebula, wh... | the survivability of newly-formed dust grains in supernova remnants |
a review is given of low-energy cosmic rays (1 mev-10 gev), which play an important role in the physics and chemistry of interstellar medium of our galaxy. according to the generally accepted theory of star formation, cosmic rays penetrate into molecular clouds and ionize the dense gaseous medium of star formation cent... | the irreplaceable role of ubiquitous cosmic rays in the space chemistry: from the origin of complex species in interstellar molecular clouds to the ozone depletion in the atmospheres of earth-like planets |
we use numerical mhd simulations, run with the public pluto code (mignone et al. 2012), to follow the evolution of supernova remnants. we consider the full evolution from days after explosion to late in the adiabatic phase. for these calculations we consider spherically symmetric evolution. for power-law ejecta profile... | using mhd simulations to construct analytical models for supernova remnant evolution |
the [o iii] emission in old supernova remnants takes the form of long, crisp filaments, while the h alpha and [s ii] emission is frothy and clumpy. that indicates that instabilities in cooling gas behind the shock produce strong turbulence. this very rapid generation of turbulence is not considered in the picture of gl... | instabilities and turbulence in a cygnus loop shock front |
x-ray observations of cas a have revealed filamentary non-thermal rims tracing the forward shock of the supernova remnant (snr). these structures have been identified as synchrotron radiation from shock-accelerated electrons with tev energies, interacting with the compressed, and probably amplified, local magnetic fiel... | the expansion and width of the synchrotron filaments associated with the forward shock of cas a |
ngc 6946 is a relatively nearby (6.7 mpc), face-on spiral galaxy with active star-formation activity throughout, including a bright nuclear starburst. ngc 6946 holds the record for production of observed supernovae, with some 10 in the last century (and four just since the turn of the millennium). hence, it is a prime ... | the fireworks galaxy, ngc 6946: looking at the fading embers |
we present h-alpha and [o iii] narrow-band images obtained with the hubble space telescope (hst) of a well-studied shock along the north-eastern perimeter of the cygnus loop supernova remnant. the h-alpha emission traces the thin, rippled non-radiative shock front, and the [o iii] emission, with a wider spatial profile... | multi-epoch hst imaging of a non-radiative shock in the cygnus loop supernova remnant |
in young supernova remnants (snrs; ~2000 yrs old), interactions between the shockwave and interstellar neutral gas play a key element in understanding the origin of cosmic rays and their high-energy radiation. fukui et al. (2012) demonstrated good spatial correspondence between the tev gamma rays and total interstellar... | shock-cloud interactions in young gamma-ray supernova remnants: evidence for cosmic-ray acceleration |
when a supernova erupts, the ejecta resulting from the explosion of the progenitor star expands into the surrounding circumstellar medium (csm), forming three key elements: 1) a forward shock in the csm, 2) a reverse shock in the ejecta, and 3) a contact discontinuity between the ejecta and the csm. this contact discon... | a design of a laser-driven experiment scaled to supernova remnants |
in the last decade, thanks to the development of the space-based and ground-based gamma-ray telescopes, more and more gamma-ray-bright supernova remnants (snrs) were found in the gev-tev band, making the research on gamma-ray emission from snrs become one of frontiers in modern astrophysics.the characteristics of gamma... | the origin of γ-ray emission from supernova remnants |
diffusive shock acceleration (dsa) is a very efficient mechanism of high energy particle acceleration in heliosphere, supernova remnants, stellar winds and gamma-ray bursts. we present microscopic simulation of particle injection and diffusive shock acceleration which is performed with 3d divergence-conserving second-o... | hybrid modeling of diffusive shock acceleration in collisionless shocks in multispecies plasma |
we revisit the spectral analysis of the set of archive xmm-newton observations of sn 1987a through our 3-d hydrodynamic model describing the whole evolution from the onset of the supernova to the full remnant development. for the first time the spectral analysis accounts for the single observations and for the evolutio... | the physical origin of the x-ray emission from sn 1987a |
we analyze for the first time the full set of archive xmm-newton epic observations of the galactic supernova remnant ic 443. we aim at identifying the contribution of the shocked ejecta and interstellar medium and at the describing the physical and chemical properties of the shocked plasma. we also aim at addressing th... | analysis of the xmm-newton observations of ic443 |
interpreting observations of the universe's most energetic phenomena requires a detailed understanding of particle acceleration in astrophysical environments. in particular, these accelerated particles, or cosmic rays, are responsible for non-thermal emission observed in supernova remnants, novae, agn winds, and a host... | understanding the multi-wavelength emission from astrophysical shocks |
some supernova remnants, including cassiopeia a, show filamentary structures in their synchrotron radiation. the two main models accounting for the formation of these filaments differ in their prediction of the narrowing, or not, of the filaments with energy. in this talk, we will describe our observation of such a nar... | observation of the narrowing of the synchrotron filaments with energy in cassiopeia a |
supernova remnant (snr) models have been developed to explain the observed characteristics of snrs, and thus to deduce their physical properties. one important part of modelling is use of hot plasma (x-ray) emission models to derive temperature and amount of shocked plasma and the snr shock velocity. coupled with a snr... | models for measuring explosion energies and ism densities of supernova remnants in the galaxy |
there is a clear connection between the evolutionary properties of a massive star and the properties of the resultant supernova and remnant. here we present new results where we have modeled 45,000 core collapse supernova remnant models to ages of 5000 years, and synthesized spectra for both the shocked circumstellar m... | inferring the properties of core collapse supernova progenitors with machine learning |
rx j1713.7-3946 is the brightest tev supernova remnant, so it is an important test case for cosmic-ray acceleration. the absence of ambient thermal x-ray emission (together with only moderate absorption) indicates that the gas is tenuous. since a central compact object sits at the center of the remnant, the mainstream ... | understanding gamma-ray emission of rx j1713.7-3946 |
we present wide-field, spatially and highly resolved spectroscopic observations of balmer filaments in the northeastern rim of tycho's supernova remnant in order to investigate the signal of cosmic-ray (cr) acceleration. the spectra of balmer-dominated shocks (bdss) have characteristic narrow (fwhm ~ 10 km s-1) and bro... | balmer-dominated shocks in tycho's snr: omnipresence of crs |
a multi-wavelength investigation of the star forming complex iras 20286+4105, located in the cygnus-x region, is presented here. near-infrared k-band data is used to revisit the cluster / stellar group identified in previous studies. the radio continuum observations, at 610 and 1280 mhz show the presence of a hii regio... | radio and infrared study of the star forming region iras 20286+4105 |
we 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... | mhd simulation of supernova remnants |
we propose a 72 ks xmm-newton epic observation toward g7.7-3.7, acandidate historical supernova remnant (snr), with the aim of pinningdown its association to the guest star which appeared in 386 ce for 2--4months. if confirmed, g7.7-3.7 would be one of four historical type-iisnrs, enlarging the small sample that is use... | is g7.7-3.7 the remnant of a low-luminosity historical supernova in 386 ce |
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