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i review the recent developments in the theory of diffusive shock acceleration (dsa) by using both first-principle kinetic plasma simulations and analytical theory based on the solution of the convection/diffusion equation. in particular, i discuss the conditions for efficient particle acceleration, the generation of m... | acceleration at snr shocks: state of the art and challenges |
the young galactic supernova remnant cassiopeia a (cas a) provides us with the clearest look at the properties and explosion dynamics of a high mass, core-collapse supernova (ccsn). with an explosion date around 1670, cas a is the youngest galactic core-collapse snr known and, at an estimated distance of 3.4 kpc, it is... | an hst survey of cassiopeia a's reverse shock, high-velocity ejecta, and shocked clouds of pre-sn mass loss |
while the bulk of gev-100 tev cosmic rays (crs) can be accelerated at the shock of the most common supernova remnants the problem of cr acceleration to and above the pev regime is still an open issue. we give a brief discussion of the production of 100 pev regime cosmic rays by supernovae in young compact clusters of m... | high-energy cosmic rays from supernovae in young clusters of massive stars |
we present the first optical identification and confirmation of a sample of supernova remnants (snrs) in the nearby galaxy ngc 3344. using high spectral and spatial resolution data, obtained with the cfht imaging fourier transform spectrograph sitelle, we identified 128 snr candidates based on four criteria that includ... | 3d optical spectroscopic study of ngc 3344 with sitelle: i. identification and confirmation of supernova remnants |
magnetized collisionless (λmfp > >lshock) shocks are created throughout the universe including within super-nova remnants and the earth's atmosphere. these shocks can generate energized, ionized particles and radiation belts. the radiation belts exist for longer durations and extend over greater distances than pr... | observations of high-ma, magnetized, collisionless shocks on the omega facility. |
we propose to conduct a detailed study of two supernova remnants (snrs) of type ia origin- snr 0509-67.5 and snr dem l71 using 1-dimensional hydrodynamic modeling for snr evolution and non-equilibrium ionization calculations for the state of the shocked plasma. our models for the two remnants are based on realistic con... | linking type ia supernovae and supernova remnants: understanding the explosion mechanism |
it is generally assumed that the most part of galactic cosmic rays is produced by supernova remnants through diffusive shock acceleration (dsa). to be involved in dsa particles should be picked up from thermal pool. this issue is known as injection problem and still remains unresolved. here we present results of 2d3v p... | physics of nonrelativistic perpendicular shocks of young supernova remnants: electron injection, energy redistribution and magnetic turbulences |
molecular gas is the densest and coldest phase of the interstellar gas and regarded as the nursery of stars. so far a quarter of galactic supernova remnants (snrs) have been found to be associated with molecular clouds. most of them are core-collapse snrs with massive progenitor stars, but there is emerging evidence to... | supernova remnants in the molecular environments |
core-collapse supernovae (sne) are found in galaxies with ongoing star-formation. if a starburst galaxy hosts an active galactic nucleus (agn) with a relativistic jet, the sn could take place inside the jet. the collision of the sn ejecta with the jet flow leads to the formation of a shock, where particles could be acc... | non-thermal emission produced by the interaction of a jet with a supernova remnant |
in the galaxy, most snrs were first detected as extended non-thermal radio sources. by contrast, in galaxies beyond the magellanic clouds, most snrs have been identified as emission nebulae with elevated [s ii]:ha emission ratios compared to hii regions. ngc6946, which has had more historical sne than any other galaxy,... | what makes radio-detected and optically-detected supernova remnants in ngc6946 different? |
we present optical images of the vro 42.05.01 (g 166.0+4.3) supernova remnant in hα+[n ii], [o iii] 5007 and [s ii] at a moderate angular resolution. low and high-dispersion spectroscopy and high-resolution imaging were also performed at selected areas around this extended remnant. diagnostic diagrams of the line inten... | optical study of the peculiar supernova remnant vro 42.05.01 (g 166+4.3) |
non-equilibrium plasmas are plasmas that are either underionized or overionized relative to the electron temperature, and thus are dominated by radiative recombination or collisional ionization, respectively. they are important for a variety of transient x-ray sources such as supernova remnants (snr), solar flares, and... | benchmarking x-ray emission from non-equilibrium plasmas with an electron beam ion trap |
along with the central black hole the processes of active star formation play very important role in the energetics of the galactic center region. the sne and their remnants (snrs) are the main ingredients of the processes of star formation. snrs are also the sources of electromagnetic radiation of all wavelengths from... | supernova remnants in the gc region |
how does a young supernova (sn) develop into a remnant? while theoretical models provide a prescription for the time evolution of the radius, velocity, temperature and x-ray emission, they have not been validated against long-term observations, because the latter have not been available. we propose a 40 ks observation ... | chandra follows sn 1986j into its 4th decade |
the cygnus loop is among the brightest and best studied evolved galactic supernova remnants. however, its distance has remained uncertain thus undermining quantitative understanding about many of its fundamental properties. here we present moderate-dispersion spectra of stars with projected locations toward the remnant... | the cygnus loop's distance, properties & environment driven morphology |
it is now well established that supernova remnants (snrs) accelerate particles to cosmic ray (cr), but there are many important issues yet to be determined, such as the efficiency of the process of particle acceleration at snr shocks, the effect of cr production on the evolution of snrs, and how local magnetic fields a... | hess j1731-347: a synchrotron x-ray dominated supernova remnant |
cosmic rays can power the growth of a seed magnetic field by exciting a non-resonant insta- bility, which can help confine and accelerate high energy particles in supernovae remnants and young stellar jets shocks. this work aims at elucidating the behaviour of the non-resonant cos- mic rays streaming instability in col... | enhancement of the non-resonant streaming instability by particle collisions |
one of the most important themes in research of supernova remnants (snrs) over the last 10-20 years has been cosmic-ray acceleration by snr shocks. the detection of synchrotron emission from radio up to x-rays has proved that young snrs can accelerate electrons up to energies of 10-100 tev. it was also shown that snr s... | synchrotron radiation in cas a: the non-linear connection |
collisionless shocks are ubiquitous in astrophysics and a possible source of the highest-energy cosmic rays in our universe. over the last decade, experimental and numerical efforts have shown that ion-weibel instability is a leading candidate mechanism for collisionless shock formation in unmagnetized astrophysical ob... | laboratory study of the initial stages of quasi-parallel collisionless shocks relevant to supernova remnants (snr) |
the chandra observations towards the northwest (nw) and northeast (ne) rims of supernova remnant (snr) rcw 86 reveal great detail about the characteristics of the shocks, particle acceleration and the local environments in these 2 distinct regions. both the nw and ne of rcw 86 show clear evidence of non-thermal x-ray e... | the northern rims of snr rcw 86 - chandra's recent observations and their implications for particle acceleration |
we present o caesar, the optical catalogue of extragalactic supernova remnants. o caesar will provide the largest homogenous optical survey of extragalactic snr candidates taken by the same telescope (canada-france-hawaii telescope, cfht), the same instrument (sitelle), and in similar observation parameters. sitelle, t... | o ceasar: the optical catalogue of extragalactic supernova remnants |
the detection of non-thermal x-ray emission from supernovas remnants(snrs) provides us a unique window into studying particle accelerationat their shock-front. all of the ~14 snrs in which non-thermal x-raysynchrotron emission has been detected are shell-like in nature, andshow no evidence of interaction with large nea... | the rare case of snr g346.6-0.2: the non-thermal mixed-morphology snr |
cosmic ray acceleration in supernova remnants is characterized by turbulence and magnetic field amplification created by streaming cosmic rays. physics upstream of the shock is most important for acceleration; both the scale and the magnitude of the magnetic field have to be large enough to ensure sufficiently rapid ac... | nonlinear streaming instability and super-diffusion of particles |
supernova remnants (snrs) and their progenitors will largely affect the surrounding star formation activity, not only the formation process of young stellar objects (ysos) but also the property of molecular clouds (mcs). we examined the relationship between the distribution of ysos and snrs in our galaxy, based on 2mas... | star-formation activity around supernova remnants in our galaxy--snr g127.1+0.5 and snr hb3 |
interstellar dust is both a tracer of galaxy evolution and plays an active role in that evolution. the presence of dust accelerates star formation by catalyzing molecule formation, which leads to rapid cooling and condensation of gas. at the same time star formation and the accompanying feedback leads to dust destructi... | dust destruction in the inhomogeneous interstellar medium |
supernova remnants (snrs) are thought to be the most plausible sources of galactic cosmic rays. one of the principal questions is whether they are accelerating particles up to the maximum energy of galactic cosmic rays (∼pev). in this work, a systematic study of gamma-ray-emitting snrs is conducted. our purpose is to m... | observational constraints on the maximum energies of accelerated particles in supernova remnants |
we present a multi-epoch, high resolution (r ~ 100,000) study of ultraviolet interstellar c i absorption line profiles taken by the hubble space telescope. the 17 stars of this survey were chosen because each has high resolution spectra taken at least 10 years apart with the same instrument (stis), grating (e140h), and... | a search for au-scale c i structure in the diffuse ism |
sn 2012z was a type iax supernova, the largest class of peculiar white-dwarf supernovae, and is the only white-dwarf supernova that has been detected in pre-explosion observations. we will present hubble space telescope observations of sn 2012z taken four years after explosion. surprisingly, the sn has remained brighte... | models for the late-time excess flux of the peculiar iax sn 2012z |
we present asymmetric kinematics of the hot fe ejecta in kepler's snr, the remnant of the sn ia observed in 1604, revealed using doppler velocity measurement (kasuga et al. 2018, pasj, 70, 5, 88). the ejecta kinematics of young snrs is an important clue to understanding the explosion mechanism of their progenitors. the... | doppler velocity measurement of fe ejecta in kepler's supernova remnant |
sn 1987a is the great supernova of the hst era. it is the only casewhere we have detailed knowledge of the pre-existing structure in thecircumstellar gas. it is the only case where we can observe thedetails of a transition from supernova to supernova remnant. anunbroken string of observations is the essential tool for ... | saints: images of sn 1987a |
cygnus loop and ic 443 are supernova remnants (snrs) recognized as excellent laboratories to study the interaction between the snr and the surrounding interstellar medium. the overall complex morphologies and large dimensions of those snrs have always represented an observational challenge. this is especially true for ... | multispectral analysis of cygnus loop and ic 443 with ifts |
distances to galactic supernova remnants are important to determine their actual location in our galaxy, as well as the energetics and age and some possible association with compact objects. however, for many galactic supernova remnants there are no clues on this important quantity. in the case of supernova remnants wi... | optical counterparts of galactic supernova remnants and their kinematic distances |
supernova remnants are one of the primary engines through which stars add energy to the interstellar medium. the efficiency of this transfer of energy is enhanced where supernova remnants encounter dense interstellar gas, such as in molecular clouds. unique signatures have been observed toward these supernova remnant/m... | a survey for galactic supernova remnant/molecular cloud interactions ssing carbon monoxide |
(invited talk) the snr paradigm for the origin of cosmic rays (cr) requires that the bulk of galactic crs are accelerated at the blast waves of snrs. in this talk i will review the current status of the theory of shock particle acceleration with a special focus on the non-linear effects produced by accelerated particle... | particle acceleration at snr shocks |
supernova remnats (snrs) show a complex morphology characterized by an inhomogeneous spatial distribution of ejecta, believed to reflect pristine structures and features of the progenitor supernova (sn) explosion. filling the gap between sn explosions and their remnants is very important for a comprehension of the orig... | modeling post-explosion anisotropies of ejecta in snr cassiopeia a |
the galaxy cluster a2146 is undergoing a major merger and hosts two huge, bright mach 2 shock fronts, which provide a unique opportunity to measure the electron-ion thermal equilibration timescale along with other key transport phenomena. collisionless shocks occur over a wide range of scales from accretion shocks to s... | shock structure, the electron-ion equilibration timescale and the disintegrating cool core in a2146 |
non-equilibrium plasmas, i.e., plasmas that are dominated by either radiative recombination or collisional ionization, are important for a variety of transient x-ray sources such as supernova remnants (snr), solar flares, and cluster shocks. in many of these sources, the details of the cooling/heating mechanisms that l... | laboratory studies of x-ray emission of highly-charged ions in non-equilibrium collisional plasmas |
observations of ia supernovae have been invaluable in measuring distances on cosmological scales and led to the discovery of the accelerating universe. even though it is accepted that these supernovae are the result of thermonuclear explosions of accreting white dwarf stars, little is known on the progenitor systems. o... | single-degenerate or double-degenerate? the case for a third epoch observation of the confirmed ia supernova remnant 0509-67.5 |
we present our results on the range and time evolution of the maximum energy that charged particles can obtain while they are accelerated in the forward shock of supernova remnants resulting by type ia supernovae (sne ia). in particular, based on semi-analytical and numerical descriptions, we investigate the dynamics o... | the effect of circumstellar medium on cosmic ray acceleration in type ia supernovae |
polarized radio emission has been mapped with great details in several galactic supernova remnants (snrs). the polarization of synchrotron emission contains a wealth of information but has not yet been exploited to the extent it deserves. we have developed a numerical method to model the maps of the stokes parameters f... | magnetohydrodynamic simulations of the polarized radio emission of the adiabatic snrs in ism with nonuniform distribution of density and magnetic field |
recently, a new class of evolved supernova remnants (snrs) with centrally peaked fe-rich emission has been identified in the magellanic clouds. the fe-rich cores result from reverse shock-heated ejecta, the composition of which is consistent with a type ia explosion, and are spectrally evident as very pronounced fe l-s... | evolved fe-rich supernova remnants in the large magellanic cloud with athena |
in the studies of electrostatic shocks a distinction is made between electrons, that freely pass the shock structure and those that get trapped into the shock potential. if the width of the trapping region in velocity space is bigger than the change of the electron velocity by collisions over the evolution time of the ... | modelling of ion-acoustic shocks with reflected ions |
a failed core-collapse supernova from a non-rotating progenitor can eject mass due to a weakening of gravity associated to neutrino emission by the protoneutron star. this mass ejection mechanism yields observable transients and sets an upper limit to the mass of the remnant black hole (bh). here we report on global hy... | mass ejection in failed supernovae: equation of state and neutrino loss dependence |
high-mach-number collisionless shocks are found in planetary systems and supernova remnants (snrs). electrons are heated at these shocks to temperatures well above the rankine-hugoniot prediction. however, the processes responsible for causing the electron heating are still not well understood. we use a set of large-sc... | kinetic simulations of high mach shocks: pic simulations vs in-situ measurements |
we study production of secondary cosmic rays (cr) in supernova remnants (snr). the model includes reacceleration of already existing in interstellar medium secondary cr particles as well as creation of secondary crs in nuclear collisions of accelerated protons with gas nuclei and their subsequent acceleration by snr sh... | contribution of supernova remnants to crs secondary to primary ratios |
we will report on optical proper motion measurements of the tycho (sn1572) and sn1006 remnants, based on ccd images at multiple epochs with total baselines of over twenty years. optical emission from both tycho and sn1006 is almost entirely in the balmer lines of hydrogen, and arises from pre-shock neutral atoms that p... | expansion measurements of young type ia supernova remnants and the physics of nonradiative shocks |
the comparison between observations and models of balmer-dominated emission in supernova remnants may represent a powerful way to gather information on the physical conditions in their shocks, like on their structure, on the ambient medium properties, on the cosmic-ray acceleration efficiency. we will focus here on the... | interplay between physics and geometry in balmer filaments |
the supernova remnant sn 1006 is a source of high-energy particles and its southwestern nonthermal limb is interacting with a dense ambient cloud, thus being a promising region for gamma-ray hadronic emission. we performed 3-d magnetohydrodynamic simulations modeling the evolution of sn 1006 and its interaction with th... | modeling the shock-cloud interaction in sn 1006: particle acceleration and non-thermal emission |
astronomical masers are useful probes of the physical conditions of the gas in which they are formed. masers form under specific physical conditions and therefore, can be used to trace distinct environments. in particular, collisionally excited 36 and 44 ghz methanol (ch3oh) and 1720 mhz hydroxl (oh) masers are found a... | characterizing supernova remnant and molecular cloud interaction sites using methanol (ch3oh) masers |
we present new-generation mechanisms of magnetic fields in supernova remnant shocks propagating to partially ionized plasmas in the early universe. upstream plasmas are dissipated at the collisionless shock, but hydrogen atoms are not dissipated because they do not interact with electromagnetic fields. after the hydrog... | magnetic field generation by charge exchange in a supernova remnant in the early universe |
m31n 2008-12a is the single most important nova system in m31. with an unprecedented 9 observed eruptions in just 9 years, an ultra-high mass white dwarf, a high accretion rate, and low ejected mass, it is the leading pre-explosion supernova type ia progenitor candidate in any galaxy. our team uncovered a vast elliptic... | the super-remnant of the recurrent nova m31n 2008-12a - a signpost to type ia supernovae? |
galactic cosmic rays are thought to be accelerated by shocks in supernova remnants. low-energy cosmic rays (lecrs) effectively ionize neutral iron atoms and then the neutral iron line at 6.4 kev is emitted. enhancement of the neutral iron line due to lecr protons was observed near the galactic center. in this paper, we... | probing low-energy cosmic rays with observations of the neutral iron line in the w51 complex |
the cygnus loop is among the brightest and best studied evolved galactic supernova remnants. however, its distance has remained uncertain thus undermining quantitative understanding about many of its fundamental properties. here we present moderate-dispersion spectra of stars with projected locations toward the remnant... | the cygnus loop's distance, properties, & environment driven morphology |
last few years, we have presented various results of high-resolutionspectroscopies of snrs with the rgs on board xmm-newton. among them,one of the most interesting topics is possible detections of the chargeexchange x-ray emission (cx) in a few galactic supernova remnants(snrs). the condition and physical mechanism tha... | investigating charge exchange x-ray emission in g296.1-0.5 with the rgs |
we present preliminary results of our xmm-newton/rgs observation of the southeastern ejecta knots in tycho's supernova remnant. the rgs successfully resolved numerous emission lines including o he-alpha, o ly-alpha, and fe l lines. line broadening was measured to be ~3 ev for the o he-alpha and ~4.5 ev for fe l lines. ... | high-resolution x-ray spectroscopy of southeastern knots in tycho's snr with xmm-newton/rgs |
we performed molecular line observations toward cas a and its environment with iram 30m telescope, aiming to answer the following questions: is the snr interacting with mcs? what are the properties of the mcs? the molecular clouds (mcs) along the line of sight of cas a do not show optically thin, shock-broadened 12co l... | molecular gas toward supernova remnant cassiopeia a |
supernova remnants (snrs) have long been studied in the x-ray, ultraviolet (uv), optical, and infrared (ir) bandpasses with important tracers of the interaction between snr shocks and the ism material they collide with found in the far-ultraviolet (fuv). the spectral features that trace shock fronts occur in the cygnus... | infuse: observing the non-radiative to radiative shock transition in the cygnus loop snr with a rocket-borne fuv integral field spectrograph |
for over five decades, the mechanism of explosion in core-collapse supernova continues to remain one of the last untoppled bastions in astrophysics, presenting both a technical and physical problem.motivated by advances in computation and nuclear physics and the resilience of the core-collapse problem, collaborators ad... | critical resolution and physical dependenices of supernovae: stars in heat and under pressure |
radio and x-ray observations of supernovae (sne) acquired inthe poorly sampled phase of years to decades post-explosion arenecessary to drive progress in several fundamental areas of explosivetransient research. bright emission ~years to decades post explosionof extragalactic sne may be due to a) shock-interaction with... | a survey of late-time x-ray emission in vlass detected supernovae |
supernova shocks have been long-favored as sites for accelerating cosmic rays (cr). they have been studied extensively in multiple wavebands to look for signatures of accelerated particles in the strong amplified magnetic fields created at shock fronts. in this proposal, we present an optical-only study of cr accelerat... | measuring cosmic ray acceleration in a young supernova remnant in the large magellanic cloud: the case for a third epoch observation of snr0519-69.0 |
superhero is a balloon-borne hard x-ray (20-75 kev) telescope that couples high-angular resolution (~20 arcsecs) electroformed-nickel grazing incidence optics to state-of-the-art fine pixel-pitch (250 µm) cadmium-telluride detectors with a 6 m focal length. this telescope, currently in the proposal phase, will have the... | superhero: the next generation hard x-ray focusing telescope |
models of hydrogen-poor and energetic core-collapse supernovae often invoke engine-driven mechanisms associated with the formation of compact objects that input energy into the explosion. determining whether black holes or neutron stars play key roles in these explosions remains contentious, as only circumstantial evid... | the compact remnant in the extraordinary type ib sn 2012au |
the richtmyer-meshkov instability (rmi) and its transition to turbulence appear in many astrophysical events and engineering applications, such as supernova remnant formation, supersonic combustion, and inertial confinement fusion. in this talk, a multi-mode rmi problem with the variable-density turbulence induced by r... | high-resolution simulations of richtmyer-meshkov instability and variable-density turbulence induced by reshock |
we present the publicly available moving-mesh hydrodynamics code sprout. sprout solves the equations of ideal hydrodynamics on an expanding cartesian mesh. the expanding mesh can follow fluid outflows for several orders of magnitude with very little numerical diffusion, thereby capturing shocks and fine structures accu... | sprout: a moving mesh hydro code using a uniformly expanding cartesian grid |
we report the detection of γ-ray emission coincident with the supernova remnant (snr) kes 41, using data from the large area telescope on board the fermi gamma-ray space telescope. kes 41 is believed to be interacting with molecular clouds, as evidenced by observations of hydroxyl (oh) maser emission at 1720 mhz in its... | combining mev-gev γ-ray and x-ray observations: a broadband view of supernova remnant kes 41 |
non-thermal x-ray emission has been detected from young shell-type supernova remnants (snrs). these x-rays are believed to be synchrotron radiation from electrons accelerated to tev energies at the shocks, interacting with the compressed, and possibly amplified, local magnetic field. accurate determination of shock vel... | measuring the proper motion and flux time variability of the x-ray synchrotron filaments in the nw of rcw 86 |
supernova remnant (snr) n132d, located in the large magellanic cloud, represents a unique opportunity for the study of gamma-ray emission from shock-accelerated cosmic rays (crs) in another galaxy since it stands as the first and only extra-galactic snr detected in gamma-rays. n132d is one of the brightest snrs in the ... | the monster next door: fermi-lat observations of supernova remnant n132d in the large magellanic cloud |
the detection of non-thermal x-ray emission from supernova remnants (snrs) provides us with a unique window into studying particle acceleration at the shock-front. all of the 14 or so snrs in which non-thermal x-ray synchrotron emission has been detected are shell-like in nature, and show no evidence of interaction wit... | g346.6-0.2: the mixed-morphology supernova remnant with non-thermal x-ray emission |
we present our latest results of two-dimensional core-collapse supernova simulations for about 400 progenitors. our self-consistent supernova models reveal the systematic features of core-collapse supernova properties such as neutrino luminosity and energy spectrum, explosion energy, remnant mass, and yield of radioact... | systematic features and progenitor dependence of core-collapse supernovae |
we propose a 200 ks observation of one of the most peculiar supernova remnants known: g350.1-0.3. this mysterious object resembles no other known snr in radio or x-rays, it contains a compact central object (cco) which may or may not be related. previous spectral analyses are contradictory, but there appears to be stro... | the peculiar, asymmetric core-collapse supernova remnant g350.1-0.3 |
the fast shocks in supernova remnants are known to accelerate particles to extremely high energies. the acceleration process is closely tied to the magnetic field structure in the shock region. this, in turn, can be modified considerably by the shock. synchrotron emission from the shock regions provides crucial details... | x-ray polarization in supernova remnants |
cosmic rays still have an unknown origin. many mechanisms have been suggested for their acceleration including quasars, pulsars, magnetars, supernovae, supernova remnants, and galactic termination shocks. the source of acceleration may be a mixture of these and a different mixture in different energy regimes. using num... | cosmic ray acceleration from multiple galactic wind shocks |
3c 397 (g1.1-0.3) is a bright supernova remnant recently identified as a type ia. we use neutral hydrogen absorption to derive a new distance to 3c 397. the distance allows determination of shock radius and density of the x-ray emitting gas. the harder component x-rays come from the bulk of the gas with low density, an... | the supernova remnant 3c 397: distance and evolutionary state. |
we present sofia hawc+ band d (at 154 microns) polarization observations of the young supernova remnant (snr) cas a. the polarization map shows high polarization fractions at 5-30 percent level and their variation across the snr, indicating that snrs may be a strong polarization source in far-ir. the high polarization ... | far-ir polarization and dust properties in the supernova remnant cas a using sofia hawc+ |
galactic cosmic rays (crs) are accelerated by astrophysical shocks, primarily supernova remnants (snrs), via diffusive shock acceleration (dsa), an efficient mechanism that predicts power-law energy distributions of crs. however, observations of both nonthermal snr emission and galactic crs imply cr spectra that are st... | galactic cosmic ray acceleration with steep spectra |
based on our latest chandra data, we report on the updates in the evolution of supernova remnant (snr) 1987a. the high resolution dispersed spectrum, taken in march 2018 with our deep (340 ks) hetg observation, shows that the heα to lyα line flux ratios for the si and mg ions have considerably decreased (by ~40%) betwe... | recent x-ray evolution of supernova remnant 1987a |
the superior resolution and sensitivity of jwst at near- and mid-infrared wavelengths open new pathways to answer critical questions about the nature of supernovae via investigations of young supernova remnants. this talk will outline jwst's potential to provide observations that complement those at high energies, and ... | understanding supernovae via their remnants in the era of jwst |
supernova remnant blastwave dynamics and ejecta chemistry provide insight into the evolution and ultimate fates of massive stars. g292.0+1.8 is a ~ 3000 year old supernova remnant which is bright in x-ray emission from shocked ejecta and circumstellar material. g292 has been observed with chandra for nearly 1 ms, prima... | an archival study of g292.0+1.8 |
we describe a chandra observation of the supernova remnant (snr) s8 in the nearby irregular galaxy ic 1613 (distance 725 kpc). chandra resolves the only known snr in ic 1613, revealing a nearly circular morphology. we compare the x-ray morphology with halpha and radio images. the snr is approximately 5.5 arc seconds in... | the x-ray resolved supernova remnant s8 in the nearby dwarf irregular galaxy ic 1613 |
radio, optical, and x-ray observations of this rather faint, old, lmc supernova remnant are described. the [oiii] emission forms a distinct shell, the remnant of the outer shock, which encloses the radio and x-ray emission and gives an estimate of age and explosion energy. because of a collision with an lmc hα filament... | chandra observation of the large magellanic cloud supernova remnant j0550-6823 |
supernova remnants (snrs) have long been regarded as major production sites of galactic cosmic rays. recent high energy gamma-ray observations by agile and fermi lat have proved that protons, which dominate the composition of galactic cosmic rays, are indeed accelerated in shocks of snrs through detection of emission f... | recent observational studies on particle acceleration in supernova remnants |
one of the most important themes in x-ray research of the supernova remnants (snrs) over the last 10-20 years has been cosmic-ray acceleration by snr shocks. the detection of the x-ray synchrotron emission has proven that young snrs can accelerate electrons to energies up to 10-100 tev, which requires a high level of m... | x-ray synchrotron filaments in cas a: the radio connection |
synchrotron x-ray emission, which arises from electrons being accelerated by the shock front of a supernova remnant (snr), has been detected predominantly in young shell type remnants. the detection of synchrotron x-ray emission allows one to investigate the properties of the underlying particle population. using a ∼47... | searching for evidence of non-thermal x-ray emission from supernova remnant w49b |
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 |
using forcast aboard the stratospheric observatory for infrared astronomy to image dust emission at 7.7, 19.7, 25.2, 31.5, and 37.1 μm, we reveal the presence of ~0.01 m⊙ of warm (td ~ 100 k) dust near the center of the ~104 yr-old sgr a east supernova remnant (snr) located at the galactic center. we argue that the dus... | old supernova dust factory revealed at the galactic center by sofia/forcast |
one aim of supernova remnant (snr) evolution models is to deduce fundamental properties of a supernova (sn) explosion from the current state of its snr. the snr hot plasma is characterized by its observed x-ray spectrum, i.e., electron temperature, emission measure and abundances. this plasma is heated by the snr forwa... | population analysis of supernova remnants in the galaxy |
the ability of shocks in the outer shells of supernova remnants (snrs)to accelerate cosmic rays up to the knee above 1 pev is stronglydependent on the nature of the turbulence in the shock environs. theparadigm of field enhancement through current-driven instabilities haspromoted high levels of turbulence of unexpected... | x-ray intensity and polarization probes of turbulence in supernova remnants |
the detection of non-thermal x-ray emission from supernova remnants (snrs) provides us with a unique window into studying particle acceleration at the shock-front. all of the 14 or so snrs in which non-thermal x-ray synchrotron emission has been detected are shell-like in nature, and show no direct evidence of interact... | g346.6-0.2: non-thermal x-ray emission from a mixed-morphology supernova remnant |
it is becoming increasingly evident that the spectra of cosmic rays accelerated in supernova remnants (snrs) are noticeably softer than the commonly used diffusive shock acceleration (dsa) theory predicts. we propose a simple physical explanation for this discrepancy by considering a spherical shock expanding into an i... | soft cosmic ray spectra from supernova remnants |
dust grains are the major reservoir of heavy elements and play significant roles in the thermal balance and chemistry in the interstellar medium. where dust grains are formed and how they evolve in the ism are one of the key issues for the understanding of the material evolution in the universe. although theoretical st... | akari observations of dust processing in merger galaxies: ngc2782 and ngc7727 |
astrophysical objects such as herbig-haro and supernova remnants can produce supersonic plasma outflows. these objects can generate plasma jets through radiative cooling and collisionless shocks. to study plasma jet dynamics, experiments were conducted on ceszar (compact experimental system for z-pinch and ablation res... | collisionality studies of supersonic plasma jets on a 500 ka, 160 ns linear transformer driver |
the rapidly-expanding ejecta in supernova remnants drive fast shocks in the surrounding medium. these shocks heat the ambient gas and create conditions suitable for the acceleration of charged particles to energies exceeding hundreds of tev. these particles are believedto form the primary component of galactic cosmic r... | energetic particles in supernova remnants: results from vhe observations |
in transient x-ray sources, such as supernova remnants (snr), solar flares, and cluster shocks, prevalent heating or cooling mechanisms lead to the presence of plasmas in non-equilibrium ionization (nei) conditions. these plasmas present as recombining plasmas (overionized, dominated by radiative recombination), ionizi... | updates on simulating non-equilibrium ionization plasmas with the llnl ebit-i electron beam ion trap |
investigations of vhe gamma-ray sources by any methods, including mirror cherenkov telescopes, touch on the problem of the cosmic ray origin and, accordingly, the role of the galaxy in their generation. shalon observations have yielded results on galactic supernova remnants (snr) of different ages. among them are: the ... | shell-type snrs as sources of cosmic rays |
the origin of cosmic rays (crs) is a long standing problem in astrophysics. crs spectrum breaks at 10^15.5 ev which is called the knee energy. a perpendicular shock acceleration has been considered an efficient acceleration mechanism candidate to reach crs up to the knee energy. it is suggested that the escape process ... | three dimensional global test particle simulation of cosmic-ray acceleration and escape in supernova remnants |
collisionless shocks exist across diverse plasma environments. examples are supernova remnants, comets, near planets, and interplanetary (ip) shocks in the solar wind. as the shock mach number increases, so does the complexity of the ion distribution functions at the shock front due to features such as whistler precurs... | ion reflection observed at high mach number interplanetary shocks: solar orbiter observations |
the detection of non-thermal x-ray emission from supernova remnants (snrs) provides us with a unique window into studying particle acceleration at the shock-front of an snr. all of the 14 or so snrs in which non-thermal x-ray synchrotron emission has been detected are shell-like in nature, and show no evidence of inter... | g346.6-0.2: a rare mixed-morphology supernova remnant with non-thermal x-ray emission |
an analytical solution for a spherically stratified medium is constructed on the strength of an earlier obtained exact solution of kompaneets equation for the shock front in a planar stratified medium with the density changing as the hyperbolic tangent. the solution obtained allows to build entirely the shock front and... | on the theory of the of-central explosion in a spherically stratified medium |
in this poster, we present a sitelle optical identification and confirmation of a large sample of supernova remnants (snr) candidates in the nearby spiral galaxy ngc 3344 and its impact on the measurement of the star formation rate (sfr). sitelle, the imaging fourier transform spectrograph of the canada-france-hawaii t... | 3d optical spectroscopic study of ngc3344 with sitelle: i. identification and confirmation of supernova remnants |
a core-collapse supernovae (sne) is the final stage of evolution for massive stars (m > ~8 solar masses). these sne play roles in a broad range of astrophysics including the synthesis of metals and the formation of compact remnants in the universe. quantification of these roles requires a better understanding of the... | simulated uv and x-ray observations of the newly proposed shock interaction and breakout explorer (sibex) midex mission |
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