XMM-Newton 2019 Science Workshop “Astrophysics of hot plasma in extended X-ray sources” 2019-06-12 European Space Astronomy Centre (ESAC), Madrid, Spain

Modelling and simulations of remnants

Gilles Ferrand Research Scientist Astrophysical Big Bang Laboratory (ABBL) and Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS) + A. Decourchelle, S. Safi-Harb + S. Nagataki, D. Warren, M. Ono, F. Röpke, I. Seitenzhal Modelling and simulations of supernova remnants with a focus on morphological studies

Introduction to SNRs

Structure and evolution of a remnant Multi-wavelength emission

1. SNRs as particle accelerators

Hydro-kinetic coupling for diffusive shock acceleration (DSA) Non-equilibrium ionization and thermal emission from the plasma Magnetic field amplification and non-thermal emission from the particles

2. SNRs as probes of the explosion

From the supernova to the remnant: Cas A, Tycho Example: the N100 supernova model X-ray image analysis Supernova remnants 0.1 SNRs as a key link between stars and the ISM

Tycho’s SNR age: ∼440 yr distance: 1.5–5 kpc enrichment in heavy elements size: 8’ ∼3–12 pc average stars: up to C-O massive stars: up to Fe supernovae: above Fe

hot, turbulent metal-rich plasma

injection of energy heating of the gas hydrodynamic turbulence magnetic field amplification multi- wavelength composite image: - X-rays acceleration (Chandra) of particles - Optical large, powerful (Calar Alto) shock wave most favoured Galactic sources - infrared 15 (Spitzer) up to the knee (< 10 eV) 0.2 Classification of SNRs

from radio + X-ray observations

SNR 0509-67.5 W49B G21.5-0.9 Crab

shell composites filled-centre

“mixed morphology” plerionic isolated/shell-less = thermal composite: composite (= non- wind nebula centrally peaked thermal composite): = PWN (= plerion) PWN inside shell or (can be both) bow shock nebula 0.3 The evolution of a

radius R non-radiative radiative

momentum-driven

values given for pressure-driven 1.4 solar masses 46 pc of ejecta with kinetic energy of 1051 erg, expanding in a Sedov-Taylor medium of density 7 pc 0.1 cm-3 ejecta-dominated

600 yr 30 000 yr time t

G1.9+0.3 Tycho RCW 86 Simeis 147 Monoceros Loop 140 yr 440 yr 2,000–10,000 yr ∼40,000 yr ∼300,000 yr 0.4 The structure of a young shell SNR

Tycho’s SNR 0.95 – 1.26 keV 1.63 – 2.26 keV as seen by Chandra 4.10 – 6.10 keV at age 433 yr Warren et al 2005 0.5 SNR broad-band emission

A&A 516, A62 (2010)

SN 1006

Fig. 6. Azimuthal profile obtained from HESS data and XMM-Newton data in the 2–4.5 keV energy band and smoothed to HESS PSF, re- stricted to radii 0.12◦ r 0.36◦ from the centre of the SNR. Azimuth ≤ ≤ 0◦ corresponds to East, 90◦ corresponds to North, 180◦ to West and 90◦ to South. − radio optical X Fig. 4. HESS γ-ray image ofgamma SN 1006. The linear colour scale is in units 2 2 of excess counts per π (0.05◦) .Pointswithin(0.05◦) are correlated. The white cross indicates× the geometrical centre of the SNR obtained from XMM data as explained in the text and the dashed circlesE cor- respond to R dR as derived from the fit. The white star shows the centre of the circle± encompassing the whole X-ray emission as derived keV by Rothenflug et al. (2004) andTeV the white triangle the centre derived by cm µm Cassam-Chenaï et al. (2008) from Hα data. The white contours corre- spond to a constant X-ray intensity as derived from the XMM-Newton λ flux map and smoothed to the HESS point spread function, enclosing respectively 80%, 60%, 40% and 20% of the X-ray emission. The inset shows the HESS PSF using an integration radius of 0.05◦. synchrotron Balmer lines atomic lines of Inverse Compton ? in B field forbidden lines heavy elements pion decay ? Fig. 7. Differential energy spectra of SN 1006 extracted from the two + synchrotron regions NE and SW as defined in Sect. 2.Theshadedbandscorrespond to the range of the power-law fit, taking into account statistical errors.

Table 2. Fit results for power-law fits to the energy spectra.

Region Photon index ΓΦ(>1TeV) 12 2 1 (10− cm− s− ) NE 2.35 0.14stat 0.2syst 0.233 0.043stat 0.047syst SW 2.29 ± 0.18 ± 0.2 0.155 ± 0.037 ± 0.031 GeV e- blast wave hot ejecta > TeV e- ? ± stat ± syst ± stat ± syst Fig. 5. Radial profile around the centre of the SNR obtained from HESS data and XMM-Newton data in the 2–4.5 keV energy band smoothed to + TeV e- HESS PSF. > TeV p ? The spectra for the NE and SW regions are compatible with Γ power law distributions, F(E) E− ,withcomparablephoton indices Γ and fluxes. Confidence∝ bands for power-law fits are centred on 143.6◦ 6.1◦ (SW region) and 29.3◦ 4.0◦ (NE − ± ± shown in Fig. 7 and Table 2.Theintegralfluxesabove1TeV region) and with similar widths of 33.8◦ 7.0◦and 27.9◦ 4.0◦. ± ± correspond to less than 1% of the Crab flux, making SN 1006 reviews (high energies perspective): Reynolds 2008, Vink 2012 one of the faintest known VHE sources (Table 2). The derived 4. Spectral analysis fluxes are well below the previously published HESS upper lim- its (Aharonian et al. 2005). The observed photon index Γ 2.3is Differential energy spectra of the VHE γ-ray emission were de- somewhat steeper than generally expected from diffusive≈ shock rived for both regions above the energy threshold of 260 GeV. acceleration theory and may indicate that the upper cut-off of the These regions correspond to 80% of the X-ray emission∼ (after high-energy particle distribution is being observed; however, the smearing with the HESS PSF) and therefore slightly underesti- uncertainties on the spectrum preclude definitive conclusions on mate the TeV emission of the full remnant. this point.

Page 4 of 7 SNRs as particle accelerators 1.1 Efficient particle acceleration

SNRs are widely believed to be the main producers of CRs in the Galaxy • Available energy budget — but can we reach the knee? • Known acceleration mechanism — but what spectrum? • Observed energetic electrons — and protons?

If CRs are efficiently accelerated by the blast wave, it must impact its dynamics - fluid becomes more compressible - energy leaks from the system → non-linearly coupled system

CRs are a key ingredient of SNRs 1.2 Diffusive shock acceleration: the coupled system

IR Opt radio UV X γ X

shock wave cosmic-rays injection, acceleration (thermal magnetized (non-thermal shock modification plasma) population)

conservation laws damping particle distribution: heating X 2 +div(F (X)) = 0 n (x, t)= f (x, p, t)4p dp t Zp u transport equation: X = u F (X)= u u + pI 0 1 0 ⌦ 1 f f 1 p3f u P (e + P ) u generationdiffusion, (instabilities) injection, + (uf)= D + 2 stochastic accelerationt x x x 3p p x @ A @ A ✓ ◆

magnetic waves hydrodynamic (collective movements kinetic treatment of charges) treatment

reviews on DSA : Drury 1983, Jones and Ellison 1991, Malkov and Drury 2001 on numerical techniques for DSA: Marcowith et al (in prep) 1.3 Numerical simulations: hydro + kinetic

slice of log(density) Teyssier 2002, Chevalier 1982, 1983 Fraschetti et al 2010 SNR initialization: SNR evolution: self-similar profiles 3D hydro code from Chevalier ramses parameters: Tycho (SN Ia)

tSN = 440 years shock back-reaction: 51 ESN = 10 erg diagnostics varying gamma n =7,Mej =1.4M Ellison et al 3 Ferrand et al 2010 s =0,n =0.1 cm H,ISM 2007 (A&A 509 L10) particle acceleration: non-linear model of Blasi

Blasi et al 2002, 2004, 2005 Anne + Caprioli 2008, 2009 Decourchelle Head of Astrophysics Dpt. Using a comoving grid to at CEA Saclay / Irfu factor out the expansion 1.11.4 Computing the emission from the SNR

Thermal emission from the shocked plasma

Samar Safi-Harb Prof. at the University of

Manitoba test-particlecase Canadian Research Chair Ferrand, Decourchelle, Safi-Harb 2012

Non-thermal emission

from the accelerated particles

modifiedshock

Ferrand, Decourchelle, Safi-Harb 2014 withmagnetic field amplification 1.5 Hydro- and thermodynamics of the plasma

Thermal emission in each cell depends on:

• plasma density n2

• electron temperature T e n progressive equilibration with protons temperature Tp via Coulomb interactions

• ionization states fi(Z) Tp computation of non-equilibrium ionization - solving the coupled time-dependent system of equations Patnaude et al 2009, 2010 - using the exponentiation method ⌧ in post-processing I t slices at t = 500 yr from a 10243 simulation with particle I = n(t0).dt0 back-reaction ZtS Smith & Hughes 2010

all these parameters depend on the history of the material after it was shocked. Ferrand, Decourchelle, Safi-Harb 2012 1.6 Thermal emission

Ferrand, Decourchelle, Safi-Harb 2012

using an emission code adapted from Mewe, with rates from

emissivity[erg/s/cm3/eV] Arnaud

1024^3 cells t = 500 yr energy [eV]

test particle vs. back-reaction test particle vs. back-reaction test particle vs. back-reaction 1.7 Magnetic field and radiative losses

Non-thermal emission in each cell depends on:

• pion decay: plasma density n(x, t)

• synchrotron: magnetic field B ( x, t) n (amplified at the shock, then frozen in the flow)

• Compton: ambient photon fields (CMB) B

Note: the acceleration model gives the CR spectra just behind the shock fp(p, x, t) ,fe(p, x, t) they must be transported to account for losses: slices at t = 500 yr from a ✓ 10243 simulation without ⇥(x, t) particle back-reaction • adiabatic decompression = and MF amplification ⇥(xS,tS) t 2 1 • radiative losses B 3 dt / ZtS Ferrand, Decourchelle, Safi-Harb 2014 1.8 Non-thermal emission

Ferrand, Decourchelle, Safi-Harb 2014 synchrotron (e) pion decay (p) using the emission code from P. Edmon

Inverse Compton 1024^3 cells (e) t = 500 yr emissivity[erg/s] energy [eV]

efficient MF amplification ➞ high B

no net MF amplification ➞ low B 1.9

mo d i fie d sho ck test-pa rticl e case w i th mag n e tic fie l d amp l i fica tio n simulations simulations observations Thermal + non-thermal emission rays – electrons (radio – X- emission from the non-thermal and therefore the field, magnetic evolution of the 2/ they impact the (optical, X-rays)shell emission the wave, and therefore dynamics of the shock 1/ they impact the as electrons, however: radiate as efficiently shock front, don’t accelerated the at Energetic protons thermal thermal γ - rays) from the

, SNRs as probes of the explosion 2.1 From the supernova to the supernova remnant

2 main types: Type Ia : thermonuclear explosion of still many competing models Type II, Ibc: core-collapse of massive star need to revive the shock: probably neutrinos

Supernova simulations in 3D explode. Sometimes. Successful explosions have a complex structure: does it impact the morphology of the remnant? What can the observed (morphology of the) SNR tell us about the explosion?

It is time to bridge SN studies and SNR studies 2.2 Cas A (from the SN) to the SNR

Fe Si/S asymmetries in the 3D SN ejecta imposed by hand ➔ can reproduce on Chandra X-ray image the overall morphology of the SNR after hundreds of years

Orlando et al on HSR optical image 2016 Conclusions: the bulk of asymmetries observed are intrinsic to the explosion 2.3 CC SNe: asymmetric explosions A. Wongwathanarat et al.: 3D CCSN simulations

a grid of parametrized core-collapse neutrino-driven explosions from different stellar evolution models from shock revival to shock breakout

Wongwathanarat et al 2015

mass fraction of 56Ni, color-coded by velocity

Fig. 7. Snapshots displaying isosurfaces where the mass fraction of 56Ni plus n-rich tracer X equals 3% for model W15-2-cw (top row), L15-1-cw time (second row), N20-4-cw (third row), and B15-1-pw (bottom row). The isosurfaces, which roughly coincide with the outermost edge of the neutrino- heated ejecta, are shown at four different epochs starting from shortly before the SN shock crosses the C+O/He composition interface in the 1 progenitor star until the shock breakout time. The colors give the radial velocity (in units of km s− )ontheisosurface,withthecolorcoding defined at the bottom of each panel. In the top left corner of each panel we give the post-bounce time of the snapshot and in the bottom left corner ayardstickindicatingthelengthscale.Thenegativey-axis is pointing toward the reader. One notices distinct differences in the final morphology of the nickel-rich ejecta of all models, which arise from their specific progenitor structures.

A48, page 11 of 20 2.4 Cas A from the SN (to the SNR)

maps of column density Fe (56Ni) 44Ti

Wongwathanarat et al 2017

showing everything after removing inner half of Fe

? Gabler et al 2016 The Astrophysical Journal, 842:13 (20pp), 2017 June 10 Wongwathanarat et al. neutrino-processed and shock-heated in the region of explosive nucleosynthesis. From the set of 3D simulations by Wongwathanarat et al. X-ray(2013), model W15-2, which we consider in the present paper, observationsdevelops a fairly large explosion asymmetry, and the NS receives a kick of 575 km s−1 until ∼3 s after the onset of the SN blast (with acceleration continuing on a low level for an one of the CC Feeven longer time). Information on hemispheric differences of the yields of nuclei included in the α-network can be found in simulation models 44TiTable 3 of Wongwathanarat et al. (2013), and visualizations of Sithe 3D distribution of the ejected nickel (compared to other happens to mimic models) can be found in Figures 14 and 15 of that paper. Even for a case with rather high NS kick like model W15-2, the morphology of radionuclei as nucleosynthesis products in the innermost SN ejecta, where the explosion asymmetry is most extreme, are not Cas A SNR Grefenstettejust expelled in one hemisphere, et butal some of this material can be ejected also on the side of the kicked NS. The exact geometry, however,2014 strongly varies from case to case, and lower NS kicks go hand in hand with more isotropic ejection of radioactive material (compare the cases displayed in Figure 14 and 15 of Wongwathanarat et al. 2013). In Figure 10 we provide a closer comparison of the 3D 44 56 Figure 9. Spatial distribution of 44Ti (blue) and of known Fe K-shell emission distributions of Ti and Ni including volumetric information. in CasA. The image is adopted from Figure 3 of Grefenstette et al. (2014) with The images of this figure show, for both nuclear species, the 4–6 keV continuum emission (white) and X-ray-bright Fe (red) seen by isosurfaces corresponding to different values of the mass Chandra (Fe distribution courtesy of U. Hwang; Hwang et al. 2004; Hwang & Laming 2012). The orientation in standard astronomical coordinates is fraction. These isosurfaces were determined such that they indicated by the compass in the lower left corner. The yellow cross marks enclose 50%, 75%, 90%, and 97% of the total mass ejected of the geometrical center of the expansion of the explosion; the white cross and the considered nucleus. the arrow the current location and the direction of motion of the central, X-ray- The plots confirm our previous conclusions drawn on the emitting compact object, respectively; and the outer and inner white dashed circles the locations of the forward and reverse shocks, respectively. These basis of the mass distributions in velocity space (Section 3.2): 44 56 features were extracted from Figure 2 and extended data Figure 1 of since Ti and Ni are nucleosynthesized in close spatial Grefenstette et al. (2014), where a detailed description of the observational data proximity in regions of (incomplete) silicon burning and the α- and corresponding references can be found. (Reprinted by permission from particle-rich freeze-out (Section 3.1), they are expelled in close Macmillan Publishers Ltd: Nature, Grefenstette et al. (2014), ©2014.) connection and there is no process at work that could decouple or decompose them in the ejecta. Their distributions therefore even greater differences might well be possible for more closely resemble each other, and the two nuclei, overall, trace the same 3D geometry. extreme cases than those obtained in the set of 3D simulations The bulk of the nickel and titanium is concentrated in of Wongwathanarat et al. (2013), or for nuclear species not relatively small, highly enriched clumps and knots that contain included in their nucleosynthesis treatment with a small half of the ejecta masses of these nuclei (see left panels of α-network. Figure 10). The majority of these clumps expand away from the In the direction where the explosion and the nucleosynthesis center of the explosion in the hemisphere opposite to the are weaker, the shock and the postshock material accelerate direction of the NS motion. A close inspection of the two left outward more slowly. On this side the nascent NS can therefore panels in comparison reveals that the lumps containing 50% of accrete for a longer period of time before the mass infall is the ejected 44Ti are considerably more extended than those of quenched by the acceleration of the SN explosion. The 56Ni, meaning that titanium is clearly more diluted. Moreover, fl momentum transfer both by hydrodynamic accretion ows one can find regions of high 56Ni concentration and little 44Ti and by the gravitational attraction from more inert, typically and vice versa. Note that all of the clumps with radial velocities denser and more massive innermost SN ejecta pulls the NS to −1 of 4000 km s (blue and light-blue colors) in the left two the side of the weaker blast wave. Thus, the NS receives columns of Figure 10 are located within the volume of the inner a kick opposite to the direction of the stronger shock sphere that is assumed not to be reverse-shock heated in the expansion, consistent with momentum conservation during right panel of Figure 8. The radius of this sphere is about half the explosion (for detailed discussions, see Scheck et al. 2006; the distance from the center to the outermost tips of the largest Wongwathanarat et al. 2013). Ni and Ti fingers. The maximum velocities of titanium in this This means that the NS experiences a recoil acceleration that inner, unshocked sphere are in the ballpark of the fastest points away from the hemisphere where the SN ejects more material seen by NuSTAR (Grefenstette et al. 2014). Our model heavy elements with atomic numbers Z ~ 14 and higher. The suggests that a considerable amount of 44Ti should exist in kick velocity of the NS depends on the stochastic explosion CasA with higher velocities outside of the reverse-shock asymmetry, the explosion energy, and the density around the radius, which is in line with the 3D data published recently by newly formed NS (see Janka 2017). The environmental density Grefenstette et al. (2017). of the NS, in turn, depends on the compactness of the The isosurfaces enclosing 90% and 97% of the ejecta masses progenitor core and determines the amount of matter that is for the two nuclei (right two columns in Figure 10) exhibit

12 2.5 From the 3D thermonuclear SN to the 3D SNR

3D simulations of thermonuclear supernovae 3D simulations of a TN supernova remnant

?

Röpke 2007, Seitenzahl et al 2013

Friedrich (Fritz) Röpke Shigehiro Prof. at Ruprecht-Karls- (Hiro) Nagataki Universität Heidelberg, Chief Scientist, Head of stellar group at Astrophysical Heidelberg Institute for Big Bang Theoretical Studies Laboratory

shocked ejecta at 500 yr Ivo Seitenzahl Research Fellow at Don Warren Ferrand et al 2010, School of Science, Masaomi Ono 2012, 2014, 2016 University of New South Research Wales (UNSW), Australia Scientists 2.6 Hydro evolution of the SNR

slices of log(density) from 1 yr to 500 yr on a 256^3 Cartesian grid (simulation made in co-expanding grid, box size increases by factor ~150)

Chevalier N100 angle-averaged N100 1D initial profile effectively 1D initial full 3D initial profile (power-law) profile (~exponential) what SNR people used to do what SN people are telling us Ferrand et al 2019 2.7 Hydro evolution of the SNR slices of t = 1 yr t = 100 yr t = 500 yr log(den sity)

N100 3Di SN phase + SNR phase

N100 1Di SNR phase only

Morphological signatures of the (thermonuclear) explosion can be seen clearly in the first hundred years, and may still be detected after a few hundred years. 2.8 Mapping the wavefronts (RS, CD, FS)

N100 3Di at t = 500 yr

forward shock

contact discontinuity

reverse shock

maps stored using HEALPix 2.9 Spherical harmonics expansion of the wavefronts contact discontinuity (CD) from 1 yr to 500 yr

3Di

1Di

Ferrand et al 2019 2.10 Rayleigh-Taylor from the SN and SNR phases contact discontinuity (CD) at 500 yr

3Di

SN modes SNR RTI

1Di

SNR RTI

Ferrand et al 2019 2.11 First conclusions and application to Tycho

Interestingly, using a realistic 3D SN model leads to larger scale and more irregular structures, which were not seen in SNR simulations made from (semi-)analytical SN models, and which better match X-ray observations of Tycho’s SNR.

1Di 3Di Ferrand et al 2019 Ferrand

Tycho looks more like this

projection along l.o.s. of the density squared = proxy for the thermal emission ➔ next will compute the synthetic thermal (and non-thermal) emission 2.12 Perspectives for type Ia SNe

Future simulations will enable us to make comparisons between different SN explosion models: • between different ignition setups for the DDT model, that produce different initial asymmetries and yields • between different SN explosion models: pure deflagration, pure detonation, other detonations, other channels… (Role of the companion star?) The Astrophysical Journal, 868:90 (12pp), 2018 December 1 Tanikawa, Nomoto, & Nakasato

Chandrasekhar-mass white dwarf

example of double-detonation double-degenerate explosion

Tanikawa et al 2018

Seitenzahl grid of DDT explosions: varying ignition patterns et al 2013

Figure 5. Distribution of density, star ID, and mass fractions of chemical elements at t=50 s. Note that, if there is no material, the star IDs “0” are assigned. We change the mushroom-shaped, unburned materials to 100% 56Ni materials. This is also true for Figures 6–10.

Figure 6. Masses of chemical elements in the SN ejecta (red), companion- Figure 7. Mass of chemical elements for the original data (black), 16 origin stream (blue), and surviving WD (black) at t=50 s. The SN ejecta fi includes the companion-origin stream. Materials of the SN ejecta and surviving subgroups of SN ejecta (red) from the ducial mass resolution simulation, and WD are gravitationally unbound and bound to the surviving WD, respectively. data from the higher mass resolution simulation (blue). The black and red curves overlay each other, since the chemical compositions are the same. have higher velocities for the viewing angles closer to the direction of the bulk velocity of the SN ejecta. The velocity This is consistent with the velocity of the binary motion of the difference is ∼(1–2)×103 km s−1 between (θ, f)=(90°, exploding primary WD, 1100 km s−1. 135°) and (θ, f)=(90°, 315°). The velocity of these elements The velocity difference does not come from the asymmetric observed from the other viewing angles is intermediate explosion of the double-detonation model. In the asymmetric between the velocity observed from the two viewing angles. explosion, when the velocity of O and Si from a viewing angle

7 2.13 X-ray image analysis with genus statistics “genus number” = no. of “clumps” - no. of “holes” for a black & white image, so for a given intensity threshold

(Euler-Poincaré characteristicGenus Statistic of on Tycho’s the Supernova excursion Remnant set) 11 10 Sato et al. where G(I ) is the genus number at the intensity thresh- Smoothing σ ~ 2.5” i Smooth model old Ii. We define the best-fit as the model with the minimum genus distance. The fits to the genus curve of the smooth model for both the Gaussian and chi-square distributions yield very similar coherence angles and dgenus values. Ad- ditionally the chi-square distribution requires large n values (>200) for the best fit which is securely in the regime where the chi-square random field approaches a Tycho’s SNR (IME) Gaussian random field. Thus we conclude that the dis- Tycho’s SNR (Fe) Smooth tribution of clumpsClumpy in the smooth model isTycho’s close SNR to a random Gaussian distribution. The genus numbers for Smoothing σ ~ 2.5” the smooth model have much larger absolute values than Clumpy model those of the genus curve for Tycho’s SNR at any smooth- ing (for one specific smoothing level see Fig. 10). The clumpy model also shows similar values for the coherence angles between the Gaussian and chi-square distributions, but in this case the genus distance is con- siderably less for the chi-square distribution, implying a better description of the genus curve. This is similar to Tycho’s SNR (IME) what we found for the observation of Tycho’s SNR (see Tycho’s SNR (Fe) –3 –2 –1 section0 3.4). Additionally1234 the coherence angles from the5 ν = u / σ clumpy model are a better match to the data for all Figure 9. Top: the sqrt scale imagessmoothing of the smooth scales. ejecta model And (left), the the genus clumpy curve ejecta for model the (middle) clumpy and Tycho’s SNR. Only the image of Tycho’s SNR is smoothedcan bydistinguish the smoothing =1.5pixels. smoothBottom: the images vs. of theclumpy central region ofejecta the profiles smooth ejecta model (left), the clumpymodel ejecta model is similar (middle) to and that Tycho’s of SNR the with observed the smoothing remnant, =5pixels.Theblueand in Figure 10. Comparison of the genus curves (in red) for the red contours show ⌫ = 1.5 and +1.5, respectively. → particularcan quantify at a smoothing (the of =obvious) 5 pixels (Figure that10). Tychosmooth is (top) not and clumpedsmooth initial ejecta (bottom) models Table 3. Summary of the best-fit parameters of the genus The genus statistic thereforerandomly. strongly Both models supports assume an the initial an exponentialfor ra- an image smoothing of =6pixels(=2004). The blue curves. · clumped ejecta distributiondial density as the profile origin of Dwarkadas of the clumps & Chevalier (1998(green)) lines show the genus curves for Tycho’s SNR with an Williamsand explosion et parameters al 2017, of 10 51Satoerg with et 1.4 alM 2019of Gaussian pdfin chi-squareTycho’s supernova pdf remnant. image smoothing =5pixels(=20046) for the energy band ? ejecta. The clumpy model is produced using a Perlin · Smoothing dGauss⇤ ✓c† d⇤ 2 ✓c† n dominated by IME (Fe) emission. Warrenn & Blondin (2013algorithm) argued to generate that thenoise presence with a maximum of angular Smooth model ejecta knots ahead of thescale forward of 20 and shock a maximum-to-minimum in Tycho’s SNR density con- 0008(=2pix) 7.9 40097.44008 271 ⇠ · · · trast of 6. These simulations using the hydrodynamics 1006(=4pix) 6.4 50076.15and SN00 10067221 can be generated by smooth ejecta without The existence of a high velocity feature (HVF) iden- · · · code VH-1 are described in detail in Warren & Blondin 2004(=6pix) 4.7 60044.86any initial003 clumpiness269 ( using2013). their three-dimensional hy- tified as the Ca II triplet at a velocity of 20,000–24,000 · · · 1 Clumpy model drodynamics simulations.Figure In order10 and to Table approximate3 show the comparison the ofkm the s in the light-echo spectrum of SN 1572 (Krause et 0008(=2pix) 8.7 60064.6600517 genus curves among the smooth ejecta model, the · · e↵ect of· ecient particle acceleration, they allowed for al. 2008)o↵ers support for initial clumping in the ejecta. 1006(=4pix) 7.2 70093.9700815 clumpy ejecta model and Tycho’s SNR. Since we do · · the adiabatic· index to be a model parameter. The sim- Similar HVFs have been found in many SNe (e.g., Maz- 2004(=6pix) 6.6 90023.7900012 not have uncertainties on the model genus curves we · · · 2 zali et al. 2005), as a result of asphericity in the explosion ⇤ the mean genus distance from theulations analytic were models. able to producecannot use clumps as the breaking figure-of-merit through function; instead † the coherence angle of the genusthe curves mean estimated shock from radiusfor as the observed comparison but here only we useif the the shockmean genus distancedue to, for example, accretion from a companion or an the best-fit analytic models. intrinsic e↵ect of the explosion itself (e.g., Wang et al. ? the order of the random chi-squarecompression pdf distribution. was quite high (a compression ratio of 11). Also, they found that ignoring the emission from ma- 2003; Kasen et al. 2003; Tanaka et al. 2006). Kasen et al. (2003) analyzed both spectroscopy and spectropolarime- terial below a certain ionization age tendedn to change model appear more filamentary and are distributed more 1 the observed morphology. Ind fact,= the diversityG (I in) imag-G (I ) , try(4) of SN 2001el and showed that both an aspherical genus n | data i model i | i ing introduced by changing the adiabaticX index and the photosphere and a single high-velocity blob can repro- ionization age cut-o↵s are not considered in the smooth duce the observations. Also three-dimensional models model we used. Those e↵ects might change the genus suggest that large blobs (opening angle: 80) or a thick ⇠ curve for the smooth ejecta model. Additionally, we ex- torus (opening angle: 60) can naturally explain the ⇠ pect di↵erences in the genus curves for each model from observed diversity in strength of HVFs (Tanaka et al. di↵erent random realizations of the initial conditions. 2006) although these structures would be much larger Viewing along di↵erent lines-of-sight would also produce in physical size than the X-ray clumps in Tycho’s SNR. di↵erent genus curves. Investigation of such studies will At a minimum, the existence of a HVF implies some be the focus of future work. kind of clumpiness in the ejecta of SN 1572. 2.14 A new way of investigating SNR kinematics

“The Hot and Energetic Universe” Athena+ supporting paper Decourchelle, Costantini, et al 2013 Let’s explore the SNR in real 3D

RIKEN Wakō Open Day

FerrandRIKEN & WarrenOpen Day 2018 2018-04-21 (CAPjournal)