SN 1987A: CSM interaction and searches for the compact
objectClaes Fransson
The Oskar Klein Centre
Stockholm University

Josefine Larsson, Dennis Alp, Tuomas Kangas,
Bruno Leibundgut, Jason Spyromilio, Anders
Jerkstrand, Peter Lundqvist, Jesper Sollerman, Roger
Chevalier, Bob Kirshner, Seppo Mattila, Mikako
Matsuura…

SN1987A JWST GTO team

PI: Gillian Wright (MIRI EC):
Patrice Bouchet, Mike Barlow (EC co-leads),
Patrick Kavanagh, Joris Blommaert, Alain Coulais,
Claes Fransson, Rene Gastaud, Alistair Glasse, Jens
Hjorth, Oliver Krause, Tuomo Tikkanen, Olivia Jones.
Jeroen Jasper
Co-PI: Margaret Meixner (USA MIRI): Alec Hirschauer,
Beth Sargent, Tea Temim, Ryan Lau, Isha Nayak, Ori
Fox, Armin Rest, Laura Lenkic, Josefin Larsson, Roger
Wesson, Nolan Habel

•
•
•
•

Progenitor and CSM structure
Ejecta – ring collision
Influence of CSI for ejecta structure and emission
Compact object

87A review in Ann. Rev. Astr. & Astroph. 2016 R. McCray & CF
General physics of CSM interaction review, including 87A, in R.
Chevalier & CF, Handbook of SNe, 2017 (on arXive)

Discovered on Feb 24 1987 in LMC close to 30 Dor.
Pre-discovery plates already from Feb 23.43
Distance 50 kpc. Magnitude at maximum +3
Progenitor Sanduleak -69o202 B3 Ia SG
log L = 5.15 – 5.45, Teff = 15-18 x 103 K, R ≈ 3 x 1012 cm
L ~ 105 LO ⇒B3Ia = Blue supergiant
R~3x1012 cm
M ~ 18±3 MO

Environment and components of SN 1987A (or when you resolve a SN)
ORejectaKangas+ 2021

RS

ER

Ejecta in homologous expansion V ∝ " ~ 5000 km/s at ring, density 100 – 105 cm-3
ER = Equatorial Ring: shocks 200 – 1000 km/s, density ~ 104 cm-3. Pre-shock ~10 km/s
RS = Reverse Shock ~10,000 km/s, density ~ 10-100 cm-3
OR = Outer Rings

First CSM indication: High ionization lines from the ionized ring with IUE
Later imaging with NTT (Wampler et al) and later HST

CF+ 1989, Sonneborn+ 1997

• Light echo from ring
• He II, C III, C IV, N III-V, O III-IV strong• Strong N enrichment N/C ≈5, N/O ≈ 1.1-1.5, as well as He/H =0.15-0.25 (by number). (Lundqvist & CF 1996, Mattila+ 2010)

Shock breakout in SN 1987A
Blinnikov+ 1998

Sapir & Halbertal 2014

Need soft X-rays Tcolor ≽ 100 eV to give N V etc (Lundqvist & CF 1996)
Shock break-out from BSG. t ~ 100 s

CSM structure at < 1 pc
Chevalier & Dwarkadas 1995

Aschenbach 2007
X-rays 0.5-2 keV~102 cm-3

The Radio Remnant of Supern
FIGURE 5. Comparison of the 0.2–2 keV [15] and the 843 MHz lightcurves [20],http://www.aip..org/pacs/index.html. Note: the X-ray flux density is unlike the radio data not inmJy but arbitrarily scaled to match best the radio data. Furthermore, the most recent radio observationsof 2007 shown may be more unreliable than indicated by the formal errors.

Zanardo+ 2017

~ 104 cm-3

Initially very weak radio à fast BSG wind(~450 km/s, )̇ ~10-7 MO/yr) --> faint radio, X-rays
Radio and X-ray turn-on at ~1500 d, not ~5000 d
Consistent with early collision with constantdensity H II region from the ionized RSG wind. n ~102 cm-3

FIGURE 6. Comparison of the 3–10 keV [15] and the 843 MHz lightcurves [20],CSM outside the rings
Crotts, Sugerman, Kunkel,
Lawrence, Heathcote..
Using light echoes on the dust to
map the 3D structure

Sugerman et al 2005
Fig. 43.—Rendered views of the probable structures containing the observed echoes. Top row: The CD nebula. Second row: The NH nebula. Third row: The CS
nebula. Fourth row: The CS hourglass. For these top four rows: left column, the face-on view of the complete structure; second column, the western half, viewed fromthe east, showing a clear view of the interior; right columns, face-on and side views of the complete structures in monotone gray, overlaid with actual echo points from
Fig. 15. For the bottom row: (q) The western halves of the CD and NH, and (r) NH and CS nebulae, viewed from the east. (s) The northern halves of the CD and NH, and(t) the NH and CS nebulae, viewed along the inclination axes from the south. See text for colors.

CSM structure from light echoes
No. 1, 2005
82

84

THREE-DIMENSIONAL MAP OF SN 1987A

SUGERMAN ET AL.

SUGERMAN ET AL.

Sugerman, Crotts 87+ 2005

Vol. 159

Vol. 159

we see that brighter echoes form a sharp, circular ridge that could
easily be mistaken for delineating the sharp edge of a narrowcylinder that was seen from ix ¼ 50" in Figure 20c.
Finally, if the CD is indeed mirror symmetric, why were
echoes not seen from the far half of the nebula (material at #z 0 )?
In particular, there is a small portion of material north of the SN
interior to the late-time paraboloids (northern points just interior to the large parabola in Figure 15b). Figure 28b shows that
Fig. 33.—Same as Fig. 28 but showing the frustum containing the horns.
echoes of this small northern portion were very faint due to theDarker shading indicates increased surface brightness of an echo. (a) The
complete frustum as revealed through a complete, regularly sampled set oflarge scattering angle, and hence were unlikely to be detected.
echoes. Random points along the intersection of the frustum with echo parabOn the other hand, a segment of the spurs along the closer halfolae from our observations are shown in panels (b) (face-on) and (c) (from theof the CD should have created very bright echoes at a radius of
top). Gray scale is normalized to the brightest and faintest points plotted, thus
shadings differ between panels (a) and (b)–(c).
! ¼ 7 lt-yr, roughly from P.A. 315" to 30" . Very little signal was
detected in this region, which may suggest that the spurs are
Fig. 38.—Same as Fig. 35, but with data inclined by the favored CS orienthan aofuniform
feature.
revolved about the z 0 -axis, then reinclined from the line of sight
41! and iyclumps,¼ 8! andrather
an ellipticity
0.94 removed
from the radii.
tation of ix ¼isolatedOuter ringsby the best-fit NH orientation to generate a complete frustum,Circles
asthat are now considered part of the hourglass are marked by open
shown in Figure 33a. As in Figure 28, gray scale indicatessquares, and the case-A only points (7.
Fig.
35) are marked byHAT
pluses. The average
NAPOLEON’S
relative brightness of echoes based on their scattering angle radialand profiles to each structure are overplotted. The dashed line shows the innerIn
contrast
totheprevious
case
of
the
echoes,distance from the SN. Points along the northern limb are edge
the of the belt, used in x 8.3. Note that there are many binned CD
averagesin thisthere ismuchless ambiguity
plot, which are
discussedin the x 8.2. over the possible structures of which thebrightest, since the scattering angle is lowest.
NH echoes are a part. As shown in Figures 15d –15f, NH apRandom points on this frustum along echo paraboloids obFig. 27.—Cartoon sketch of the salient structures traced out by the CD modelFig. 34.—Same
as Fig. surface
27, but for of
the revolution
NH echoes, withthe orientation
arrows axis,
served in our data are shown in Figures 33b and 33c. Thearpears
to be somewitha well-definedFig. 39.—Same as Fig. 27, but for the CS echoes, with the orientation arrows
from Fig. 26. This figure is to scale, with the length of the two orientation
measuring
lt-yr. with
The solid
traces the crossradial profile
from (bFigure32,0:94)
and theto the westof the4SN,
anlineellipticalsection/a ’northern
limb
was
never
illuminatedbyechoesasit
lies
insidesuch
as gray-scalea prolateregion
ellipsoid,or frustum.
However, it ismeasuring 2 lt-yr. The expected positions of the ORs are indicated by thin dotted!cylinder,rows equal to 10 lt-yr. Solid lines trace the average radial profiles, and the scatter
width
of
the
tracesthescatterofpointsabout
that
profile.
clockwise
from
east.
We
whose
semimajor
axis
isrotated9theearliest
paraboloid.
Theearliest
intersection
occurred
justabove those profiles are indicated by the solid gray-scale regions surrounding each
not immediately clear whether the two horns are part of such alines (x 8.3).
visualize thisnebulaIfby
reflecting
profilethe such aline.south of this limb, and over time, increasingly southern slices
structure.
not,
where doeach
theyradial
lie,0 andif so,0about
why haswere illuminated, becoming fainter with increasing epoch. The
P 3thenand!reinclining
k 4:5 oflt-yr.the NH
scatterportion
smallerandradii ofaxis,! The
equator, erage
revolvingittoaroundthe larger
cylindricallimitedbeen
illuminated?
geometry
bipolar peanut-like nebula, the result of many interacting-winds
the NH points
lie within
firstbrightest echoes came from the first few epochs, appearingit as
by the Furthermore,
best-fit
Theofellipticity
removedin thesemakingechoesorientation.
willoverbe one-third
quantified
in the following
subsections.
formation models. To distinguish this hourglass from the largera brief
discussion.
First,
recallthat Figures
18 and19Figureare 38linear,radial features
at weroughly
constant
north-south
position.
bins,
implies thesedata revolving
trace out anthe
equatorial
waswhich
reintroduced
when
profilesenhanceabout
consistent
with atsurfacesof rotational
symmetry.
However,roFurthermore,
the earliest
epochs, theilluminatedmaterial isment in both density and radial position. This is shown in Figure
one containing the NH echoes, we refer to each by their assothecylindrical
axis.
The
result,renderedin
Figures
43i–43j,shows
7.1. Geometry
NH fromEchoes34 as small spurs pointing
toward andofaway
the SN in theorientedclose to need
the linesight, mirror
thus theseechoes appeared
tational
symmetry
notofimply
symmetry,
as in theciation—i.e., the latter is the ‘‘NH hourglass.’’theprobable
structureoftheCSmaterial.
Colorsare
discussedeven
due to aorlimb-brightening
effect.
thenext
limitedequatorial plane. A similar,butless significant,inward-pointing
cases
ofbrightera paraboloid
cone. As we will
seeThus,in thetwo
As in previous sections, we address why only a limited
7.1.1.
Spherical
Coordinates
below.
The
next
twopanels(Figs.
43k
and43l)
comparetheportionof
thisstructurethatwasilluminatedas‘‘thehorns’’
isfeatureisseenroughly
1.5
lt-yr
along
the
axis.
CKH95
reported
sections, light echoes from material interior to the CD nebula lie
amount of this complete hourglass structure was illuminated bycomplete
structure
in
gray
to
the
observedechoes.
Herecolors
As
with
the
CD,
we
examinetheNHechoesinspherical
a
small
set
of
echoeswithin
3
lt-yr
of
the
SN
that
are
coincident
consistent
with
these
points
lying
on
the
same
hourglassastheon axisymmetric surfaces that do exhibit mirror symmetry. We
withER plane,
whichintheyinterpreted
evidence
forpointsanex- fill aechoes. Referring to Figure 43p, only the southernmost portion
rest of theNHthematerial.
coordinates,
shown
Figure29. Thebulk of theechoesare similar
totheFigures
15g–15i,only
now
allas hourglass
thereforemake(reasonable) assumption that stellar winds
tendedcircumstellar
equatorial
disk.
The(Fig.
NH 35)
equatorial
echoes# 0 ¼ 3of the near (or south) half of the hourglass was probed by thehorizontal
regionin",withpointsdistributed
betweenarecolored
red,
and
the
Case-A
only
pointsarecoloredproducing symmetricstructures
distanceswould also
7.2. A Complete
Pictureatofsmall
the NH
Structureappeartothiswedisk
to a radiusof
5 CS
lt-yr,hourglassof
5 lt-yr.
In theseearliest echo. While the greater majority of the far (or northern)and6 extend
lt-yr, butconcentrated
aroundrwith¼ 4a thickness
green. For
completeness,show
only thein Figproduce such structures at larger ones.
k0.75
lt-yr.
The probable structure containing the NH echoes isures
an 43m–43p.
coordinates,a thick spherical shell with radius r $ 4:5 lt-yr andhalf of the CS hourglass lies inside the earliest and latest echoIn
concluding
thissection,we
firstcommentonthesuggeshourglass, the waist of which has an ellipticity of b /a ¼ 0:82,
width!r a7.3.
¼scaled
1Comparison
lt-yrcartoon
would withpopulate
the same
However,parabolae, the particular sampling of our observations probed
vious
Work
Prerelevant
39
showsof theCSregion.
features.
tions
in axx6.1.3 and
6.1.4
that lt-yr
the rotated
CD hasabout
an inclinationofwithsemimajor
axisof "4.9
102# east ofFiguresuch a subsections,structure is unlikely:
if thedata
lay alonga on
sphericalthe northern edge only at the earliest epochs. A comparison of50" . Bootstrap
This is a resultoftheparticularportion
of
the
CD
that
ix ¼north.
Inthefollowing
wediscusseach
featurebased
analyses of these fits yield errors of about 3%
As NHechoes
was thesubject
ofsouthinterest
inbehindthe early
1990s,
wethe SNthis panel with Figure 36b shows that we have detected roughly
shell,
in
front
and
(or
and
north)
ofwasforimaged
inechoes,ratherthananintrinsic
propertyofthe
its radialcompare
profile theandnewly
three-dimensional
shape.
revealed material
with previous interpretaeach parameter. If the horns lie on a surface with similar
should have been observed.
all the material that could have been observed.
CDeccentricity,
itself. The probableCD isrenderedin Figureaxis
28, now
tions. Wampler et al. (1990a) first reported the discovery of thethe hourglass
flaresto a semiminorof "7shaded
lt-yr
8.2.1.
The
CS
Hour
g
lass
The
horns
are
also
inconsistentwith
spherical
structure, as
by from
the relative
brightness
ofofdust
scattering2003),
the SN along
the axis
symmetry.
The(Sugerman
entire structureis‘‘Napoleon’s Hat’’ echo in narrowband [Oiii] aand[ N ii] imaging
8.2.2. The Equatorial Plane and Belt
arenebulosity,
instead locatedin a highly
inclined,almost radial re40# south
and ix and¼ 7#compositioneast of the line
sight.The innermost
as theydiffusewhich blendedsmoothly
intobackgroundorientedat iy ¼uniform
which
assuming
density
is aoffunction
radial structureis the hourglass,shadedred inthe totalgion extending
from
6defines
to 11 lt-yr
from theSN.
Rather,To visualize
the average
from Figure
32Figuresisfilamentary
structurethat
theeasternandwestern
rims
Immediately
surrounding the CS hourglass is the thick waistof distanceand this,scattering
angle.radial
Figureprofile
28a showswhat theen43i–43j
and shownby itselfin Figures
43m andlie
43n.
In a cylNH bay’’echoes
can
along
about
thelikeequatorand arevolved
aroundaxis, thenof ensemble
a V-shapedof‘‘darksouth
of betheunderstood
SN (see Fig. to6). Wampler0
tirereflected
CD wouldlookthoughcompleteset oftheobservationsof extended high surface brightness, which we call the ‘‘belt,’’"
Figure
38,
these
are
the
crossesandsquareswithin
about
!
inder
or
hourglass.
The
distributionsofpointsonsuch
strucreinclined fromthe lineof sight
by the inclinations
just given.
et al. (1990b) further noted that the larger, arcmin-radius echoes
well-sampled
in time.
Figure28b showsonly that portionofand have colored green in Figures 43i–43j. It extends %1 lt-yr
1:5thelt-yr.fromThis
isviewed
fairlydust
cylindrical,
witha semiminoroftures,
in sphericala horizontal
The resulting
renderedin Figuresinterstellar(e.g., Xu etcoordinates,al. 1995)
fadepopulate
when axis
crossing
complete
CD thatdistribution
could haveisbeen
observed
in our43e–43h.
epochs of obalong the z 0 -axis and from 1.5 to 2.5 lt-yr in radius. To better
1.2
lt-yr,
tapering
close
to
the
equatorand
opening
justslightly
A muchlargerportionof thiswas sampled
echoesover this bay. A natural interpretation was that this bay is anservation.
Whenviewedfromthe nebula
CD symmetry
axis by
(Fig.
28c),
0
represent
the extent of this material, two profiles have been
is well
described
by seena lineofbecauseslope
at large evacuatedz . The profile
than was actually observed. This was discussed in some detailregion, andno light
echoes werethere
0 its particularly low density.0 As the background filaments loop
fitted in Figure 38, binned both in radius and along the axis. Beabove within the context of the horns, from which we con¼ 0:14 and zero point ! ¼ 1:02, suggesting an open!! 0 /! zof!
yond the outer radius of this belt, echoes lie fairly well constrained
cluded that the majority of the signal from the near half of thearound the SN, they proposedthat the progenitor’s MS winds

10 lt-yr

4 lt-yr

2 lt-yr

Conclusion: The CSM can be quite messy on different scales if binary interaction isimportant! Blue- red – blue winds interacting à shells + bipolar structures!

Several massive Galactic B-stars with ring systems

Smith+ 2013

SBW1

HD 168625 Spitzer

Blue: Ha. Red 10µ
BSG + Hour glass CSM

The ejecta - ring collisionSN 1987A ejecta – ring evolution

Larsson, CF + 2019

Ejecta: Declining until 2001, then increasing
Equatorial ring: Declining until ~1995, increasing until ~2007, then decaying

Optical, X-ray and radio evolution
HST, Chandra, ATCA

-13

He I
|

-14

[Ne III] [NeIII]+H!
HI| [Ca II] |_________| | | | ||[Ne V] [N I]
|
|

-15
|
[O II]

-16
3000

3100

-13
-14

He I

3200

[S II] Hδ
| |[Fe II]
____
| ||

|

-15

3300

Log [Flux (erg s−1 cm−2 Å−1 )]

|

3600

[Fe II] He I
|
|

Mg I]
|

3700

3800

He II
|
[Fe III] [Ne IV]|

4100[O III]He I|[Fe II]
____
|
|

4000
[O III]
|

|

Hβ

4200

4300

[N I]
|

[Fe XIV][Fe II] | [Fe II]
____
||
|
|

5200

5300

5400

[O I]
|

[O I]
| [Fe X]

-15

3900

[Fe II]
|

|

Hγ

4000

-14

[O III]

3500

|

-16

-13

3400

|
He I + H I

4400

4500

4600

4700

4800
[N II]|[Fe II] [O I]
|
|

4900

5000

He I
|

-16
5000

5100

-13
[Fe VII]
|

-14
-15

5500
[N II]

5600

5700[N II][S II]He I | |
|

|

5800

5900

6000

Hα

6000
-13

6100

6200

-15

6400

6500

6600

6700

[OII]+[Ca II][Fe II][Ca II] |[Ni II]||He I \___| |He I [Ar III]| [Fe II]
|
| |

-14

6300

6800

6900

[Ar III][Fe XI]

|

|

7000

-16
7000

7100

7200

7300

7400

-13
-14
-15

7500

7600

P17 P16[Cr II]_________________________________
|
|
|
|
|

|

|

7700

7800

P13

P12

|

|

7900

8000

P11
| [Fe II]
|

-16
8000
-13
-14
-15

8100

[S III][Fe II] |
P10 |
|

8200

8300

8400

8500

8600

8700

8800

8900

[S III]| P!

P9 [Fe II]||[Mg II]
___
| |

9000
2007
2017

|

-16
9000

9100

9200

9300

9400

9500

9600

9700

Many low and high ionizationlines up to [Fe XIV] and [Ar XIV]
FWHM ~ 200-300 km/s
Ha and Hb extremely broad|-16

UVES/VLT2007 (green)
2017 (black)

9800

9900

10000

Chandra grating spectrum

Dewey+2010

Figure 14
ChandraSi
High
EnergyTransmission Grating Spectrum of SN1987A (Dewey et al. 2009).
XIV,
Fe XXII…..
Upper spectra are from Medium Energy Grating; lower spectra are from High Energy Grating.
Red (blue) are from +1 (-1) orders.

UVES / VLTSpectral components in Ha
Hα

−13

−13
H α U ns ho cke dr ing[N I I ]log[ F lux ( e r g c m − 2 s − 1 Å − 1) ]−13.5

[O I ][N I I ]−14

Shocked ringV ~ 300-700 km/s

−14
−15
Sho cke d r ing

−14.5
−1000
Ejecta−15[S I I ]

0

1000

He I

−15.5
R e ve r s e s hoc k

Reverse shock
V~ 10,000 km/s

−16
−15

−10

−5

Un-shocked ring
V~10 km/s

05
Ve lo c ity ( 1000 k m s − 1)1015

Chevalier & Dwarkadas 1995

1. Interaction with H II region from ~ day 1500.
2. With ring ~ day 5000.
Forward shock decelerates to ~500-1000 km/s
Reverse shock into ejecta ~ 8,000 km/s at first impact, then steadydecrease in ring plane. Rapid expansion above ring plane wit ~10,000 km/s

Pun, Michael+ 2002

Ejecta density ~102 cm-3 à fast reverse shock
Ring density ~few x 104 cm-3 à slow forward shock
X-ray and UV/optical lines from slow shocks into the
ER. Vs ~ 200 - 1000 km/s
Shocks with Vs < 500 km/s radiative à optical lines.
Higher velocity shocks adiabatic à X-ray lines

Shock laboratory: Cooling shocks in real time
0.8

Nor maliz e d flux

2007
2010
2013

0.01

0

800

650

500

2007
2010
2013

Hα

Hα
Te~104 K

0.2

0.6[Fe X I V ] λ 5303
0.4

0.2

0

0
900

[Fe XIV] 5303 Å
Te ~ 106 K

0.8

0.6

0.4

2007
2010
2013

1

Nor maliz e d flux

1

600

300

0

300

600

900

900

600

300

0

300

Ve loc ity ( k m s − 1)

Ve loc ity ( k m s − 1)#0!
"*! = 3.4×10K
500 km/s

7$%%& =38

..0
42
'!
1
years
()) *+/2)" 3+#$
).#5
).#5
;
7

0$%%& = 450

100 cm4.

27 yrsFaster and faster shocks become radiative.

km/s

600

900

Ring dissolved!
Updatedring
HST broad band
R, B light& [O III]curves
filters

Narrow component =unshocked ring almost gone ⇒the whole inner ring has been
shockedShocked component slowly
fading, but will be visible for atleast a decade.

needs to be updated using the new time-dependent WFC3 inverse sensitivities.
ct only small changes.

Line emission VLT/UVESMultiwavelength view of ring collisionAlp, Larsson, CF 2021

0.5 - 2 keV
4.5 µmR-band

3 – 8 keV
9 GHz

0.45 – 0.7 keVSpitzer: Arendt+ 2020
9 GHz: Cendes+ 2018

10– 24 keV

Optical/UV, dust and soft X-rays reached maxima at 8000 days. Ring collision
Hard X-rays and radio still increasing. Mainly reverse shock

The shock is now outside ring

Larsson +, in prep.
Larsson, CF + 2019

Differance images• New spots outside of ring.
• Blastwave
and now probes the unseen CSM-Spotsoutsidering expandsin east are fading
outsidering.outside
Seenring
as in
the
shock
-Some
new spotthe
activity
thereverse
west-Expanding rim of diffuse emission - strongest in east

The reverse shock seen in He I 10 830 with JWST/NIRSpec
Larsson, CF, Sargent et al 2023, submitted, arXive

He I seen from the side in
the equatorial plane
The reverse shock (andCSM) extends far above
the equatorial plane
Inferred earlier from Ly a
(Michael+ 2003) and H a(CF+ 2013). Velocity up to~10,000 km/s above ER
plane

SBW1
Smith+ 2013

Figure 1. The new HST/WFC3 images of SBW1. Panels (a)–(c) are taken in the F502N [O III] λ5007, F656N Hα and F658N [N II] λ6584 filt
displayed in false colour. Panel (d) is a colour composite of the three HST/WFC3 images, with F502N in blue, F658N in green and F656N in r
at the position of the star, at αJ2000 = 10h 40m 18.s 60, δ J2000 = −59◦ 49$ 12.$$ 5.

Interaction effects on SN ejecta

Ejecta – ring evolution different
Ring

Ring fading, but ejecta
is brightening!
EjectaX-ray illumination of the ejecta from the outsideORejectaRS

ER

X-rays from the ring collision and reverse shock absorbed by theejecta and thermalized à optical/UVEjecta morphology in HαRadioactivity dominates,
centrally peaked‘Hole’. Only in X-ray dominated phase

X-ray input dominates
Larsson, CF et al. 2011, 2013, 2019(CF et al. 2013)

X-ray deposition

Reverse shock

20 yrs

0.1 keV

0.35 keV

1 keV

Ring collision:
EUV + soft X-rays

2 keVSoft X-rays from transmitted shocks have kT ~ 0.3-0.5 keV ⇒deposition in outer parts of ejecta = H/He rich regions
Hard X-rays with > 2 keV penetrate to, but not into, the O-core
unless very asymmetric and clumpy
Explains horseshoe-like morphology in HαLarsson, Spyromilio, CF + 2019

3D view of H2 (VLT/SINFONI), Ha (HST), CO, SiO (ALMA)
Ha (pink) and H (blue)

2 2019 March 1
The Astrophysical Journal, 873:15 (11pp),

ALMA CO(red), SiO (green) H2 (blue)
Larsson et al.

Figure 5. 3D isosurfaces of H2 (blue) and Hα (pink). The surfaces correspondto 45% of the maximal intensity for each line. The ring indicates the positionof the reverse shock at the inner edge of the ring. The dashed line and blob
show the line of sight and position of the observer, respectively. The tick markson the coordinate axis are separated by 1000 km s-1. An animated (rotating)version of this ﬁgure is available. As the animation runs, three different
semitransparent contour levels are shown for Hα (30%, 45%, and 65%
of max). The video duration is 22 s.

Figure 6. 3D isosurfaces of H2 (blue), CO (red), and SiO (green). The surfaces
correspond to 60% of the maximal intensity for each line. The ring indicates the
position of the reverse shock at the inner edge of the ring. The dashed line andblob show the line of sight and position of the observer, respectively. The tickmarks on the coordinate axis are separated by 1000 km s-1. An animated(rotating) version of this ﬁgure is available. The video shows one rotation andis 7 s in duration.

Note: Non-spherical and different spatial distributions. All within
the inner, dense metal core at < 2000 km/s, shielded from X-rays.
Mixing of H into core

(An animation of this ﬁgure is available.)

We use the HST/STIS observation from 2014 (Table 1) in(An animation of this ﬁgure is available.)

A comparison of isosurfaces corresponding to 60% of max

Ejecta in [Fe I] 1.44 µm with JWST/NIRSpec
Larsson, CF, Sargent+ 2023

Clean view of the Fe distribution.
Very asymmetrical distribution ’broken cigar’
Close to the RS

Ejecta in [Fe I] 1.44 µm

Larsson, CF, Sargent+ 2023

Fe-rich ejecta now starts to interact with the reverse shock (above
ring plane).
Should change both optical and X-ray spectrum

Searching for the compact object

Limits on a compact object in SN 1987A. Alp, J. Larsson, CF+ 2018,
Limits including ring (orange )
109

107

105

∫F∫ (Hz erg s°1 cm°2 Hz°1 )10

10

Wavelength (Å)
101
10°1

10°3

°13

°15

Herschel
Spitzer
ALMA
VLT/SINFONI

ACTA

°17

10°5

10°7

10°9
1037

Crab PWN

10°11

10

103

Fermi

1036
1035

Chandra Crab pulsar

1034

H.E.S.S.

Thermal from
Cas A CCO

1033
1032
1031

∫L∫ (Hz erg s°1 Hz°1 )

1011

1030
1029

10

°19

107

1010

1013

1016

1019
Frequency (Hz)

1022

1025

1028

Max luminosity of compact object from 44Ti input balanced bybolometric luminosity (dust and optical/IR) 240 L⊙ = 9.4x1035 erg/s (3?)(Crab spin-down energy loss is ~5x1038 erg/s, luminosity ~1.3x1038 erg/s)
For dipole dE/dt∝P-4B2 ⇒ B < 1012 (P/0.1 sec)2 G

Indications / claims for a compact object• Radio: Zanardo+ 2014
• Hard X-rays: Greco+ 2021, Alp+ 2021

Dust peak (blob) & CO + SiO hole

• Submm (ALMA): Cigan+ 2019

Dust peak corresponds to ahole at low-J SiO & CO

Cigan et al. (to be submitted)

Molecular hole
• Higher temperature• 35 K at hole and 20 K at surrounding• Higher density• A factor of 10-100 higher density at the hole
Dust peak• Warmer dust or more dust
Warmer gas & dust or high density– heating source• Concentration of 44Ti?

Mid-IR dust and line spectrum with MRS/JWST O. Jones et al, in prep.
PRELIMINARY!
[Ne III][S III][Ne II][O IV][Ne V]HI[Ar II][Ne V]

III][Ar[ArII]
HI [Ne VI][Ni II][Fe II]

Silicates[Fe II]

Dust emission dominated by shocked dust from ring interaction. Mostin prep.
lines from ring interaction + some ejecta linesJones(eg [FeetII]al.,26µm)

Scanning the MRS and NIRSpec data cubes

PRELIMINARY!
[Ar II] 6.985 µm

SN 1987A with NIRSpec/JWST

Larsson, CF, Sargent + 2023

19 MO oxygen core. Woosley & Heger 2007

NS
56Ni + He

SI, S, Ar, Ca

Rho et al.

Other young SNRs in mid-IR
Pulsar wind nebula G54.1+0.3[Ar II]

Downloaded from https://academic.oup.com/mnras/article/479/4/5101/5049023 by Stockholms Universitet user

Spitzer. (Rho et al. 2018)
Also 0540-69 (Williams+ 2008)[Ar II][Ne II][S III][S II][Si II][Cl II]

1.30(±0.07)E-04
6.49(±0.77)E-06
9.27(±0.41)E-6
2.12(±0.81)E-05
5.13(±0.14)E-05
6.34(±0.78)E-07
3.18(±0.71)E-06
3.51(±1.46)E-06
2.08(±0.44)E-06
3.70(±0.57)E-06

Where are the lines above~10 µ m?
6.9911 ± 0.0012
12.8231 ± 0.0065
18.7338 ± 0.0021
33.5004 ± 0.0062
34.8920 ± 0.0023
14.3374 ± 0.0051
14.3748 ± 0.0028
14.3729 ± 0.0066
14.3347 ± 0.0013
14.3801 ± 0.0022

0.0682 ± 0.0033
0.1481 ± 0.0169
0.1302 ± 0.0058
0.2599 ± 0.0100
0.3055 ± 0.0086
0.0173 ± 0.0213
0.0331 ± 0.0074[Cl II] 0.0399 ± 0.0167[Cl II] 0.0185 ± 0.0039
0.0371 ± 0.0057

Smith et al 2009

are fit with two (2) or one (1) Gaussian component(s) (Fig. 7).

De-reddened S.B.
(erg s−1 cm−2 sr−1 )01.43(±0.08)E-04

7.68(±0.90)E-06
1.11(±0.05)E-05-502.31(±0.09)E-05
5.55(±0.15)E-05
7.13(±0.88)E-07-1003.58(±0.80)E-06
3.95(±1.64)E-06
2.34(±0.49)E-06-1504.16(±0.64)E-06

150

100

Velocity(kms−1 )Shift(kms−1 )

...
...
...
...
...
384 ± 447
680 ± 153
832 ± 348
386 ± 081
777 ± 118

...
...
...
...
...
–634 ± 107
129 ± 58
106
1±
pc137
–690 ± 30+254 ± 4650
0-50∆α (arcsec)

-100

-150

[FeII][OIV][SIII][SiII]

50[FeII][SIII]

Surface brightness(erg s−1 cm−2 sr−1 )∆δ (arcsec)

Line FWHM(µm)[NeII][NeV][NeIII]ed spectral line brightness from Spitzer IRS spectrum.

[ArII]

[SIV]

100

140
120
100
80
60
40
20
0

[ArIII]

Cas A Spitzer
Mainly shock excited[NiII]

r IRS spectra of G54.1+0.3. The red curve is the low-res spectrum and the blue is150
from the high-res spectrum from the shell component of the‘blob’ emission in the southwestern shell). The green curve is the high res spectra measured in the central region. The line at 14.35µm shows
locity) components in emission as listed in Table 2.

Wavelength(µm)[Ar II]SMITH ET AL.

νIν (10-6 W/m2/sr)

714

20
15
10
5
0
5

PAH

10
15
20
Wavelength (µm)

30

Dust absorption

Young SNR ejecta (Cas A, G54.1+0.3, .. ) show dominance of silicates.
Total (cold) dust in 87A 0.2-0.4 MO (Cigan+ 2019)
Silicates likely to dominate in center (eg Mg2SiO4)
Silicates have a sharp drop in absorption at ~ 8 µm à
Flux at longer wavelengths will be heavily absorbed if A > > 1
2
May be seen later when A ∝ 6 % < 1
For large grains scattering may be important at short wavelengths.

What is the ionizing source?
Candidates• Pulsar wind nebula (mini Crab). L < 1036 erg/s power law UV - X-ray• Cooling NS Teff ~4x106 K, L < 5x1035 erg/s (Page et al. 2020)• Shock from PWN expansion• Accretion

Summary• SN 1987A excellent case for studying the complexities of
CSM interaction and shocks. May not be so special!
• BSG progenitor, abundances, rings best explained bybinary merger. Different structure compared to single star.
• CSM structure can be very complex, especially forbinaries. Rings, toruses, hour glasses, spirals…
• Ejecta - CSM interaction sensitive to CSM structure. Cf SN
2014C• We are now seeing the effects of the energy input fromthe CSM interaction on the ejecta emission.
• Ejecta highly asymmetric. Test case for explosion models.
Spectral simulations should take take this into account.
• Strong evidence for central ionizing source in 87A.