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canonical accretion models of type ia supernovae predict that a hot and luminous progenitor will ionize the surrounding gas out to a radius of ∼10-100 pc for ∼100,000 years after the explosion. tycho’s supernova of 1572 was a type ia explosion which produced a remnant that is currently interacting with neutral gas in t... | the progenitor of tycho’s supernova was not hot and luminous |
observations show that in sbc galaxies (milky-way-type) the ratio of thermonuclear to core-collapse sne is ~1/3 (mannucci et al. 2005a&a...433..807m). adding thermonuclear snrs, this indicates a ratio of snrs to wts γ-ray sources in our galaxy of order 33-65. we can check this argument by counting the snrs and γ-ra... | vizier online data catalog: modelling of wind and supernovae shocks (gupta+, 2020) |
we propose to revisit the eastern bright knot of the puppis a supernova remnant. the first-epoch chandra observation revealed clear shock-cloud interactions. the second-epoch observation proposed here will reveal various shock motions there. in addition, we will obtain better quality spectra than the first-epoch observ... | kinematics and emission processes at the prominent shock-cloud interaction site in puppis a |
recent reanalysis of data from the fermi gamma-ray space telescope has resulted in the first detection of high-energy gamma rays emitted from a nearby galaxy. this discovery reveals more about how supernovae interact with their environments.colliding supernova remnantafter a stellar explosion, the supernovas ejecta exp... | found: a galaxy's missing gamma rays |
background: cosmic rays (crs) up to 10^15 ev are likely to be produced in supernova shocks. diffusive shock acceleration (dsa) requires efficient particle scattering, suggesting that a) magnetic field is amplified at the shock and b) particles generate turbulence and self-scatter in these fields. while a number of mech... | particle acceleration in supernova remnants |
we propose a 100 ksec gto observations of n132d, the brightest supernova remnant in the local group. when combined with 800 ksec of awarded ao20 time and 86 ksec of archival data, it will permit an unprecedented look at the spatial distribution of iron and other heavy elements in the ejecta from this prototypical core-... | gto portion of a legacy observation of n132d, the most luminous snr in the local group |
an on-going question about astrophysical collisionless shocks is whether electrons and ions reach different temperatures downstream of a supernova remnant shock or whether they equilibrate. we investigate the electron heating mechanism in collisionless, non-relativistic, quasi-perpendicular, electron-ion shocks from fi... | electron heating in non-relativistic perpendicular shocks |
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? |
we apply snr interior structure models to galactic supernova remnants (snr) in the vgps survey to obtain properties of the galactic snr population. the models include the evolution of snr interior structure for both forward and reverse shocks, and calculate forward and reverse shock x-ray emission measures at any time.... | applying models with reverse shocks to galactic supernova remnants in the vgps survey |
based on our deep chandra acis observation, we present the spatial distributions of individual elements of the shocked metal-rich ejecta in the textbook-type galactic core-collapse supernova remnant g292.0+1.8 (g292). to separate the complex network of overabundant ejecta-dominated regions from low-abundant circumstell... | mapping x-ray ejecta distribution in the galactic core-collapse snr g292.0+1.8 |
understanding the star formation processes is one of the fundamental problems of modern astrophysics. star formation takes place on very large range of the temporal and spatial scales and at the different physical conditions. star formation is an inherently complex phenomenon that involves many physical processes from ... | supernova remnants in star forming regions. |
the presence of dense clumps in the environment where a supernova remnant expands might have a strong impact in shaping the observed hadronic gamma-ray spectrum. a detailed numerical study about the penetration of relativistic protons into clumps which are engulfed by a supernova remnant shock is here presented, taking... | particle propagation in clumpy supernova remnants |
compressible turbulence has been a subject of active research within the space physics community for the last three decades, it is actually believed to be essential for understanding the physics of the solar wind (for instance the heating of the fast wind), of the interstellar medium (in cold molecular clouds) and othe... | compressible mhd turbulence in the earth's magnetosheath: estimation of the energy cascade rate using in-situ spacecraft data |
abstract:the supernova remnant n49, located in the large magellanic cloud (lmc), is widely researched because of its relatively young age and its location near a dense, dusty molecular cloud in the interstellar medium (ism). n49 has entered into its radiative phase more quickly than to be expected for the age of this r... | dust destruction in the supernova remnant n49: additional wifes integral field data analysisrachel quigley, rachael huxford, parviz ghavamian, mike dopita |
spatially-resolved spectroscopy is an extremely powerful tool in x-ray analysis of extended sources, but can be computationally difficult if a source exhibits complex morphology. for example, high-resolution chandra data of bright galactic supernova remnants (cas a, tycho, etc.) allow extractions of high-quality spectr... | fevers and chills: separating thermal and synchrotron components in snr spectra |
there is general consensus that the flux of cosmic rays (crs) below a few pev originates in galactic sources. around 3 pev the cr spectrum shows a significant break, the so-called cr knee, that could originate from the fact that galactic cr sources reach their maximal acceleration energy, or that cr escape from the mil... | galactic neutrino sources |
we present the results of a detailed investigation into the physical conditions in interstellar material interacting with the supernova remnant ic 443. our analysis is based on an examination of high-resolution hst/stis spectra of two stars probing predominantly neutral gas located both ahead of and behind the supernov... | physical conditions in shocked interstellar gas interacting with the supernova remnant ic 443 |
the aim of this proposal is to maximize the scientific return of existing and future multiwavelength observations of the supernova remnants (snrs) from core collapse supernovae (ccsne). our main deliverable will be a grid of models that will allow the community to interpret cc snr observations in terms of the basic fea... | connecting supernovae and their progenitors to supernova remnants: end to end dynamical and spectral modeling of core collapse supernovae to the remnant phase |
our understanding of the progenitors of many stellar species, such as supernovae, massive and low-mass he-burning stars, is limited because of many poorly constrained aspects of stellar evolution theory. for my dissertation, i have focused on using local group galaxy surveys to constrain stellar evolution scenarios by ... | the origin of stellar species: constraining stellar evolution scenarios with local group galaxy surveys |
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 chandras recent observations and their implications for particle acceleration |
we propose to observe the filaments in the supernova remnant w50, ``eastern ear'', likely formed by the jet from the microquasar ss433. when a 100ks chandra image is compared to an xmm-newton image from 2004, the terminal velocity of the jet is measured with an accuracy of 0.33+/-0.08''/year, a tenfold improvement on p... | resolving the terminal shock driven by the jet from a microquasar ss433 at the eastern ear of w50 |
hydroxyl (oh 1720 mhz) masers in supernova remnants are understood to arise in the interaction between a compression-type supernova shock and a molecular cloud. these masers may offer constraints on problems as wide-ranging as star formation and cosmic-ray acceleration. the masers in ic443 are unique among this class o... | search for variability and proper motion of the oh (1720 mhz) masers in supernova remnant ic443: vlba, wsrt, and lwa observations |
we present an overview of the supernova remnants/proxies for reionization/ and integrated testbed experiment (sprite) cubesat. sprite is a 6u cubesat designed to carry out two science objectives while simultaneously flight testing two luvoir-lumos enabling technologies: protected elif mirror coatings and low-background... | the sprite cubesat: far-ultraviolet imaging spectroscopy of galaxies and nebulae in a small technology demonstration package |
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 |
type ia supernovae (sn ia) have enormous importance to cosmology and astrophysics, but their progenitors and explosion mechanisms are not understood in detail. recently, observations and theoretical models have suggested that not all thermonuclear white-dwarf supernova explosions are normal sn ia. in particular, type i... | left behind: a bound remnant from a white dwarf supernova? |
compressible turbulence has been a subject of active research within the space physics community for the last three decades, it is actually believed to be essential for understanding the physics of the solar wind (for instance the heating of the fast wind), of the interstellar medium (in cold molecular clouds) and othe... | compressible mhd turbulence in the earth's magnetosheath: estimation of the energy cascaderate using in-situ spacecraft data |
based on our deep 530 ks chandra acis data we perform the detailed spatially-resolved spectral analysis of the textbook-type galactic core-collapse supernova remnant (snr) g292.0+1.8. we reveal spatial distributions of the overabundant ejecta and the low-abundant circumstellar gas components over the entire snr in unpr... | distributions of shocked ejecta and circumstellar gas in the galactic core-collapse supernova remnant g292.0+1.8 |
we revisited the archival xmm-newton and chandra data of the thermal composite snr kes 41(g337.8-0.1), performed a millimeter observation toward this source in the 12co, 13co, and c18o lines, and explored the 5.6-yr fermi observational data. the x-ray emission, mainly concentrated toward the southwestern part of the sn... | a multiwavelength study of the thermal composite snr kes41 confined in a molecular cavity |
a structure of highly unusual composition and kinematic properties exists near the center of the galactic oxygen-rich supernova remnant puppis a. our wifes integral field observations indicate that the structure (referred to as 'the swirl') consists of multiple rings of high velocity ($\sim$ -1300 km/s) material around... | metal-rich ejecta rings in puppis a: kinematics and composition |
we have analyzed the archival chandra x-ray observatory observations of the compact feature in the small magellanic cloud supernova remnant (snr) 1e 0102.2-7219 which has recently been suggested to be the central compact object remaining after the supernova explosion. in our analysis, we have used appropriate, time-dep... | on the x-ray properties of the putative central compact object in 1e 0102.2-7219 |
we present near-infrared ifu and mos observations of two bright [fe ii] line emitting supernova remnants (snrs). the two snrs, g11.2-0.3 and rcw103, are selected from our near-infrared [fe ii] 1.64 um narrow band imaging survey of snrs such as ukirt unbiased [fe ii] imaging survey of the the galactic plane and aat [fe ... | near-infrared ifu and mos observations of supernova remnants |
cassiopeia a is one of only a handful of young supernova remnants to exhibit time variations in thermal and nonthermal x-ray emission. here, i will present results from a multiyear effort to study the evolution of this extraordinary object. with observations taken on a nearly yearly timescale, we are able to track the ... | twenty years of cas a with chandra |
supernovae (sne) are energetic explosions that signal the end of a star's life. these events and the supernova remnants (snrs) they leave behind play a central role in stellar feedback by adding energy and momentum and metals to the interstellar medium (ism). emission associated with these feedback processes, especiall... | new observational insight on shock interactions toward supernovae and supernova remnants |
the vast majority of supernova remnants (snrs) in our galaxy and nearby galaxies have been discovered through radio observations, and only a very small number of the snrs catalogued in the milky way have not been detected in the radio band, or are poorly defined by current radio observations. the study of the radio emi... | radio emision from supernova remnants |
collisionless shocks are common phenomena in space and astrophysical systems, including solar and planetary winds, coronal mass ejections, supernovae remnants, and the jets of active galactic nuclei, and in many the shocks are believed to efficiently accelerate particles to some of the highest observed energies. only r... | laboratory observation of high-mach number, laser-driven magnetized collisionless shocks |
in the framework of the sardinia radio telescope (srt) early science program, we obtained single-dish high-resolution imaging of the supernova remnants ic443 and w44 at 7 ghz. by coupling them with srt 1.5 ghz maps, we provided spatially-resolved spectral measurements that are highlighting a spread in spectral slope di... | evidence for a wide electron spectra scatter among different snr regions from high radio-frequency observations |
we report the discovery of a new supernova remnant (snr) candidate in the narrow-band [fe ii] 1.644 um line imaging survey uwife (ukirt widefield infrared survey for fe). uwife covers the first quadrant of the galactic plane (7degrees < l < 62degrees, |b| < 1.5degrees), and, by visual inspection, we have found... | a new supernova remnant candidate in the uwife [fe ii] line survey |
supernova remnants (snrs) are one of prominent objects in infrared (ir) emission, and their infrared-to-x-ray (irx) flux ratios are generally thought to indicate the relative importance of dust cooling to gas cooling in hot dusty plasma. but recent high-resolution ir space missions show that snrs have diverse morpholog... | infrared supernova remnants and their infrared to x-ray flux ratios |
x-ray observations provide a key window into supernova remnants, providing measurements of a plethora of physical properties that are critical for understanding snrs, their environments, their progenitors, and the sne that created them. however, characterizing the entire volume of shocked plasma in a snr is difficult, ... | exploring supernova remnants with the spies project |
the role of the non-resonant firehose instability in conditions relevant to the precursors of supernova remnant shocks is considered. using a second order tensor expansion of the vlasov-fokker-planck equation we illustrate the necessary conditions for the firehose to operate. it is found that for very fast shocks, the ... | on the cosmic ray driven firehose instability |
collisionless shockwaves are associated with a plethora of processes throughout the universe. supernova remnant shocks are considered one of the main mechanisms that are capable to accelerate particles at high enough energies as the ones observed in cosmic rays. it is still unknown how these shocks accelerate particle ... | application of single spacecraft methods to study the motion of the venusian bow shock |
we present fabry-pérot interferometric observations of the narrow hα component in the shock front of the historical supernova remnant tycho (sn 1572). using ghαfas (galaxy hα fabry-pérot spectrometer) on the william herschel telescope, we observed a great portion of the shock front in the northeastern (ne) region of th... | hα imaging spectroscopy of balmer-dominated shocks in tycho's supernova remnant |
cas a is one of only a handful of young supernova remnants to exhibit time variations in thermal and nonthermal emission, and is the only remnant to show evidence for an evolving, young central neutron star. here we propose to continue our multicycle monitoring program with three 50 ksec observations of cas a spaced by... | continued multicycle monitoring of the young galactic supernova remnant cassiopeia a |
recent gamma ray observations show that middle aged supernova remnants interacting with molecular clouds can be sources of both gev and tev emission. models involving re-acceleration of pre-existing cosmic rays in the ambient medium and direct interaction between supernova remnant and molecular clouds have been propose... | time-dependent diffusive shock acceleration in slow supernova remnant shocks |
we propose an acis-i observation of the least studied of the five galactic supernova remnants dominated by x-ray synchrotron emission, g330.2+1.0, to measure expansion and shock velocities, and to search for small-scale structure (thin rims) present in the others. comparison of our proposed 150 ks observation with 2006... | characterizing the least studied galactic synchrotron-dominated supernova remnant: g330.2+1.0 |
supernova remnants (snrs) are believed to accelerate particles up to high energies, at least reaching a few pev, through the mechanism of diffusive shock acceleration (dsa). detection of synchrotron radio emission from cosmic ray (cr) electrons supports this picture. we use two-dimensional hydrodynamic simulations of s... | radio evolution of supernova remnants including non-linear particle acceleration |
the nearly face-on spiral galaxy m83 (d=4.6 mpc) provides a significant opportunity for finding and studying a large and diverse sample of snrs all at the same distance, given its active star formation, a starburst nuclear region, and at least six sne since 1923. as the result of a concerted effort involving ground and... | x-ray, optical, and radio properties of the extensive snr population in m83 |
a stochastic particle energization by magnetic reconnection in a strong turbulent shock is discussed. the strong shocks, whose mach numbers are greater than several tens, are often observed in planetary shocks in the outer heliosphere such as saturn's bow shock, and would be also expected in high-speed interplanetary s... | particle acceleration by magnetic islands in a strong turbulent shock |
we present a range of steady-state photoionization simulations, corresponding to different assumed shell geometries and compositions, of the unseen postulated rapidly expanding outer shell to the crab nebula. the properties of the shell are constrained by the mass that must lie within it, and by limits to the intensiti... | probing physical conditions in the crab nebula with emission line analysis |
two outstanding questions about the physics of interstellar shock waves are 1) the degree of thermal equilibration among electrons and different ions and 2) efficiency of transfer of energy from the thermal plasma to energetic particles--cosmic rays. those questions are closely related in that both processes depend upo... | thermal equilibration and cosmic-ray acceleration in astrophysical shocks: uv spectra of the sn1006 remnant |
recent x-ray and infrared studies of the oxygen-rich supernova remnant g292.0+1.8 have shown that it is likely interacting with the circumstellar wind from the massive progenitor star (≥20 solar masses). some of this material lies in a moderately dense equatorial belt stretching across the middle of g292.0+1.8. here we... | tracing physical conditions of the circumstellar medium in the supernova remnant g292.0+1.8 |
an explanation of the unexpected rise in the positron fraction of the cosmic ray (cr) leptonic energy spectrum, is proposed. it is argued that the e+/- spectra are different because they are accelerated by a charge-sign selective mechanism. this premise was hinted at by a recent result from the ams-02 spectrometer that... | positron anomaly in galactic cosmic rays: constraining dark matter contribution |
as the observable products of explosive stellar death, supernova remnants reveal some of the most direct information on the physics of the explosions, the properties of the progenitor systems, and the demographics of compact objects formed in the supernova events. high sensitivity x-ray observations have allowed us to ... | supernova remnants in high definition |
with more than 15 years of observations of young snrs, we have a unique sample for the evolution of core-collapse sne with ages between 15 and 2000 yrs. the connection between snrs and sne remains vague though. we propose to couple the detailed density and velocity structure and spatially dependent composition derived ... | modeling the dynamics and x-ray emission of shocked ejecta in the remnants of core-collapse supernovae |
we performed molecular spectroscopy in 12co j=2-1 with the heinrich hertz submillimeter telescope toward 50 galactic supernova remnants as part of a systematic survey for broad molecular line regions indicative of interactions with molecular clouds. these observations revealed broad molecular lines toward nineteen remn... | a survey for broadened co lines toward galactic supernova remnants |
collisionless shocks - supersonic plasma flows in which the interaction length scale is much shorter than the collisional mean free path - are common phenomena in space and astrophysical systems, including the solar wind, coronal mass ejections, supernovae remnants, and the jets of active galactic nuclei. these systems... | laser-driven magnetized collisionless shocks |
we propose a 400 ks observation of the youngest galactic supernova remnant g1.9+0.3, almost certainly a type ia event. with an age of about 100 yr, g1.9+0.3 is evolving on a timescale of years. observations in 2007, 2009, 2011, and 2015 have revealed shock velocities of 14,000 km/s, a brightening synchrotron-dominated ... | evolution of the youngest galactic supernova remnant g1.9+0.3 |
we report on the investigation of a very high energy (vhe), galactic gamma-ray source recently discovered at e>50gev using the large area telescope (lat) on board fermi. this object, 2fhl j0826.1-4500, displays one of the hardest e>50gev spectra (photon index ~1.6) in the 2fhl catalog, and a follow-up observation... | 2fhl j0826.1-4500: discovery of a possible shock-cloud interaction on the western edge of the vela snr |
i present the results of large hybrid (kinetic ions - fluid electrons) simulations of particle acceleration at non-relativistic collisionless shocks. ion acceleration efficiency and magnetic field amplification are investigated in detail as a function of shock inclination and strength, and compared with predictions of ... | hybrid simulations of ion acceleration at shocks |
supernovae are violent explosions that marks the end of a star's life, the study of which has been instrumental in building our knowledge of the universe. despite decades of observations, we still do not have a clear picture of the explosion dynamics of these events. analyzing the composition and distribution of the ej... | investigating the late-time spectra of supernovae |
galactic cosmic-rays are likely produced through fermi acceleration processed in supernova remnant shocks and other exotic sources. identifying the different contributors to cosmic ray acceleration in galaxies is fundamental to understand galactic processes, how fermi acceleration works in various environments, and the... | cosmic-ray acceleration in eta carinae |
using deep optical images of the core of the ctb 80 supernova remnant, obtained with 8-m gemini-north telescope in 2016, and archival hst images of 1997, we measured the proper motion shift of a bright [oiii] structure ahead of the fast moving pulsar b1951+32 associated with the remnant. an arc shape of the structure s... | b1951+32 pulsar bow shock proper motion measurements based on gemini north 8-m telescope and hst optical observations |
collisionless shocks are common features in space and astrophysical systems where supersonic plasma f lows interact, such as the solar wind, the heliopause, and supernovae remnants. r ecently experimental capabilities and diagnostics evolved sufficiently to allow detailed laboratory investigations of high-mach number s... | kinetic simulations of particle energization by magnetized collisionless shocks in expanding laboratory plasmas |
m.j.-e. manuel general atomics, c.m. huntington, d.p. higginson, b.b. pollock, b.a. remington, h. rinderknecht, j.s. ross, d. ryutov, g. swadling, s. wilks, a.b. zylstra, h.-s. park llnl, f. fiuza, s. totoricaslac, g. gregorioxford, j. park, a. spitkovskyprinceton, y. sakawa, h. takabeosaka, h. siomit, a.b. zylstralanl... | investigation of weibel-filament growth in the nonlinear regime using laser-irradiated foils of different materials |
collisionless shocks are ubiquitous in astrophysics and are thought to be a source of magnetic field generation and particle acceleration in the universe. they can occur in supernova remnants, cataclysmic variables, protostellar jets, active galactic nuclei, and colliding galaxies. laboratory experiments with high-mach... | first direct experimental observation of weibel-mediated collisionless shock formation and the resulting nonthermal electron acceleration in laboratory experiments |
the acceleration and transport of energetic particles in astrophysical plasmas can be described by the so-called parker equation, which is a kinetic equation comprising diffusion terms both in coordinate space and in momentum space. in the past years, it has been found that energetic particle transport in space can be ... | on the fractional parker equation for the transport of cosmic rays: steady-state solutions |
supernovae are an important source of energy in the interstellar medium. young remnants of supernovae have a peak emission in the x-ray region, making them interesting objects for x-ray observations. in particular, the supernova remnant sn1006 is of great interest due to its historical record, proximity and brightness.... | first spatio-spectral bayesian imaging of sn1006 in x-ray |
supernova remnants (snrs) are the best candidates for galactic cosmic ray acceleration to relativistic energies via diffusive shock acceleration. the gamma-ray emission of snrs can provide direct evidence of leptonic (inverse compton and bremsstrahlung) and hadronic (proton-proton interaction and subsequently pion deca... | evidence for proton acceleration and escape from the puppis a snr using fermi-lat observations |
we present a simple model for clustered supernovae (sne) feedback in galaxy disks, incorporating the dynamical evolution of super-bubbles of hot ism formed from spatially overlapped sne remnants. there are two realistic outcomes for the evolution of super-bubbles in galaxy disks: (1) the expansion velocity of the shock... | clustered sne feedback: the trade-off between driving turbulence and outflows in galaxy disks |
magnetized collisionless shocks are common features in space and astrophysical systems where supersonic plasma flows interact, such as in the solar wind, the heliopause, and supernova remnants. recent experimental capabilities and diagnostics allow detailed laboratory investigations of high-mach number shocks. using pa... | on electron pre-energization by magnetized collisionless shocks in expanding laboratory plasmas |
unveiling the nature of progenitors is crucial for understanding the origin and the mechanism of core-collapse and thermonuclear supernovae (sne). while several methods have been developed to derive stellar properties so far, many questions remain poorly understood. in this paper we demonstrate an observational approac... | progenitor constraint using line ratios of the cno elements in supernova remnants |
nonrelativistic collisionless shocks, such as those in supernova remnants and galaxy clusters, can, under certain conditions, act as efficient accelerators of protons and electrons, and can equilibrate the temperatures between the species. using ab-initio particle-in-cell simulations we investigate the structure of mag... | electron heating and acceleration in nonrelativistic shocks |
this is an exciting time for the discovery of supernova remnants (snrs) in our and other nearby galaxies. snrs reflect a major process in the elemental enrichment of the ism. the study of this interaction in different domains including gamma-ray, radio, optical, ir and x-ray, allow a better understanding of these objec... | supernova remnants in the multi-messenger era |
the maximum energy of electrons accelerated by supernova remnants (snr) is typically limited by radiative losses. in this scenario, the synchrotron cooling time scale is equal to the acceleration time scale. on the other hand, the low propagation speed of a shock in a dense medium is expected to result in an extended a... | unraveling the effects of dense medium on a near to bohm-limit acceleration in kepler's snr |
context. cassiopeia a occupies an important place among supernova remnants (snrs) in low-frequency radio astronomy. the analysis of its continuum spectrum from low frequency observations reveals the evolution of the snr absorption properties over time and suggests a method for probing unshocked ejecta and the snr inter... | multi-antenna probing of absorbing regions inside and outside cassiopeia a |
we present detection of hydrogen molecular hydrogen (h2) in mid-infrared using the spitzer irs. the supernova remnant (snr) g357.7+0.3 is one of relatively unknown and under-studied snrs. we performed an irs spectral mapping centered on the northwestern shell of g357.7+0.3. the observations covered an area of 75arcsec ... | shocked gas from the supernova remnant g357.7+0.3 |
in recent works, through observations of molecular lines, we found that the supernova remnant (snr) g18.8+0.3 is interacting with a molecular cloud towards its southern edge. also it has been proven the presence of several neighboring h ii regions very likely located at the same distance as the remnant. the presence of... | study of young stellar objects around snr g18.8+0.3 |
we present the first three-dimensional measurements of the velocity of various ejecta knots in tycho's supernova remnant, known to result from a type ia explosion. chandra x-ray observations over a 12-year baseline from 2003 to 2015 allow us to measure the proper motion of nearly 60 ``tufts'' of si-rich ejecta, giving ... | the three-dimensional expansion of the ejecta from tycho's supernova remnant |
at low radio frequencies, supernova remnants (snrs) show synchrotron emission from accelerated electrons. in the millimetre regime they can also show molecular line emission if they are associated with neighbouring molecular clouds. in this thesis we present observations from the low frequency array (lofar), both from ... | radio observations of galactic supernova remnants |
the detection of very-high-energy gamma rays from supernova remnant shells testifies of the acceleration of particles at strong shocks. many aspects of the particle acceleration remain however unclear. the study of individual objects is very helpful, but the study of the entire population of snrs detected in this range... | the supernova remnant population in the very-high-energy sky: prospects for cta |
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 |
supernova remnants (snrs) offer the means to study sn explosions, dynamics, and shocks at sub-parsec scales. in this white paper, we discuss the major advances possible with x-ray spectro-imaging at arcsecond scales, with a few ev spectral resolution and a large effective area. | supernova remnants in high definition |
i will review the properties of astrophysical shocks related to their roles as accelerators of energetic particles. ab-initio simulations of collisionless shock structure reveal different regimes of particle injection and acceleration as a function of shock parameters, including magnetization of the flow and magnetic g... | particle acceleration in astrophysical collisionless shocks |
snrs are likely to be significant sources of galactic cosmic rays up to the knee. they produce gamma rays in the very-high-energy (e>100 gev) range mainly via two mechanisms: hadronic interactions of accelerated protons with the interstellar medium and leptonic interactions of accelerated electrons with soft photons... | the population of galactic supernova remnants in the tev range |
we compute the spectra of cosmic-ray (cr) nuclei and antinuclei under a scenario where hadronic interaction processes inside supernova remnants (snrs) can produce a diffusively-shock-accelerated "source component" of secondary particles. this scenario is able to explain the recent measurements reported by ams on the an... | secondary antinuclei from supernova remnants and background for dark matter searches |
shocks are a ubiquitous heating mechanism that produces non-equilibrium spectral emission. its interpretation influences our understanding of a diverse set of astrophysical processes, such as supernova remnants (snrs), molecular emission from external galaxies, agn, and, most recently, the transition of starburst to re... | cloudy as a shock modeling code: utility for hst, & looking out to jwst |
supernova (sn) explosions play a major role in the physical and chemical evolution of the interstellar medium (ism). they supply newly synthesized heavy elements and distribute them throughout the ism. and additionally, they also supply and destroy dust grains that introduce heavy elements into the ism. we observed 17 ... | a near-infrared [p ii] and [fe ii] line survey of supernova remnants in the magellanic clouds |
the supernova remnant cassiopeia a (cas a) provides the clearest look at the properties and explosion dynamics of a 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 also among the closest and bright... | a multi-bandpass acs survey of cassiopeia a: keeping up with its rapidly evolving structure |
some young supernova remnants exhibit thin filaments of synchrotron radiation coinciding with the forward shock. the two main models accounting for the formation of these filaments differ in their prediction of the narrowing, or not, of the filaments with increasing photon energy. in this presentation, we will describe... | observation of the narrowing of the synchrotron filaments with energy in cassiopeia a |
aims: the application of silicon monoxide (sio) as a shock tracer arises from its propensity to occur in the gas phase as a result of shock-induced phenomena, including outflow activity and interactions between molecular clouds and expanding hii regions or supernova remnants. for this work, we searched for indications ... | a survey of sio j = 1−0 emission toward massive star-forming regions |
while the youngest known supernova remnants, such as cassiopeia a, have been proven to be able to accelerate cosmic rays only up to $\sim$10$^{14}\,\mathrm{ev}$ at their present evolutionary stages, recent studies have shown that particle energies larger than a few pev ($10^{15}\,\mathrm{ev}$) could be reached during t... | h.e.s.s. too program on nearby core-collapse supernovae : search for very-high energy gamma-ray emission towards the sn candidate at2019krl in m74 |
the kinematics of shocks, ejecta knots, and the compact remnant of a supernova remnant give insights into the nature of the progenitor and the surrounding environment. we report on a measurement of the proper motion of x-ray knots and rims of the magnetar-hosting supernova remnant rcw 103. chandra data obtained in thre... | global deceleration and inward movements of x-ray knots and rims of rcw 103 |
conventional optical emission-line surveys of snrs in m33 used the [s ii]/hα line ration to diagnose snr candidates. type ia sne most frequently occur in a mostly neutral interstellar medium (ism) and the snr shocks are collisionless, producing balmer-dominated spectra in optical wavelengths. lacking forbidden lines, y... | searching for balmer-dominated type ia snrs in m33 |
the well-known nearby interacting system, m51 (composed of the grand-design spiral m51a = ngc5194 and its smaller spiral companion m51b = ngc5195) presents an excellent venue within which to study supernova remnants (snrs). the first galaxy to be classified as a spiral, m51 is nearly face-on, at a distance of 8 mpc whe... | optical identification and spectroscopy of supernova remnants in m51 |
a multipole expansion analysis is applied to 1420 mhz radio continuum images of supernova remnants (snrs) in order to compare type ia and core collapse (cc) snrs. because the radio synchrotron emission is produced at the outer shock between the snr and the ism, we are investigating whether the ism interaction of snrs i... | multipole analysis of radio continuum images of supernova remnants: comparison of type ia and core collapse |
galactic cosmic rays are thought to originate from supernova remnants (snrs). however, it is still poorly understood how they escape from snr shock regions. here we propose a new idea to measure timescale of proton escaping (suzuki et al. 2018, pasj, 70, 75). recent studies have indicated that most of the snrs emitting... | a systematic study on escaping of cosmic rays from snr shocks through observations of thermal x-ray plasmas |
utilizing our proper motion measurements in hovey et al. (2015) of the supernova remnant 0509-67.5, we are able to determine a dynamical offset of the explosion site from the geometric center along an approximately east-west dynamical axis where the remnant displays asymmetries in brightness and morphology. we measure ... | reviving the single degenerate scenario for the ia supernova event that formed remnant 0509-67.5 |
our deep 640 ks chandra, observation of the galactic type ia supernova remnant (snr) g299.2-2.9 show some peculiar characteristics. the central emission feature of the si- and fe-rich ejecta is generally-circular, but its western part is elongated all the way out to the westernmost outer boundary of the snr. the centra... | a chandra study of g299.2-2.9: the remnant of an asymmetric type ia explosion? |
the radio (vla) and x-ray (chandra) maps of the remnant of the tycho supernova (sn1572) are used to study the interstellar medium (ism) density and magnetic field gradients in the ambient medium surrounding the remnant. the analysis uses also the gev gamma-ray spectrum derived from the recent fermi data, the radio flux... | tycho: ambient medium structure by analysis of the supernova remnant |
we report new chandra observations of one of the few galactic supernova remnants whose x-ray spectrum is dominated by nonthermal synchrotron radiation, g330.2+1.0. we find that between 2006 and 2017, some parts of the shell have expanded by about 1%, giving a free-expansion (undecelerated) age of about 1000 years, and ... | expansion and age of the x-ray synchrotron-dominated supernova remnant g330.2+1.0 |
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