Post on 27-Jan-2021
UPDATE ON THE 3.5 KEV CANDIDATE DARK MATTERDECAY SIGNAL
Jeroen Franse
Instituut Lorentz & Leiden Observatory
TAUP 2015, Torino, Sept 9 2015
WithAlexey Boyarsky, Oleg Ruchayskiy, Dmytro Iakubovskyi, Esra Bulbul
JEROEN FRANSE | INSTITUUT LORENTZ & LEIDEN OBSERVATORY | TAUP 2015, TORINO, SEPT 9 2015 1 / 14
| INTRODUCTION
WIMPS VS SUPERWIMPS
WIMPSInteraction strength atweak scale
Correct ΩDM for massesGev – TeV
Would have shortlifetime
Made stable with newphysics
SUPERWIMPSInteraction strengthweaker-than-weak
Correct ΩDM for massesof order keV
Lifetime longer thanage of universe
Allowed to be decayingDM
JEROEN FRANSE | INSTITUUT LORENTZ & LEIDEN OBSERVATORY | TAUP 2015, TORINO, SEPT 9 2015 2 / 14
| INTRODUCTION
SUPERWIMPS IN X-RAYS
Decaying DM should decay into monochromatic X-rays
JEROEN FRANSE | INSTITUUT LORENTZ & LEIDEN OBSERVATORY | TAUP 2015, TORINO, SEPT 9 2015 3 / 14
| INTRODUCTION
TARGET SOURCES
Good targets are dark matter dominated. Specifically, sourceswith high expected decay signal strength
signal ∝ DM mass in FoV / distance2
JEROEN FRANSE | INSTITUUT LORENTZ & LEIDEN OBSERVATORY | TAUP 2015, TORINO, SEPT 9 2015 4 / 14
| DETECTIONS
DETECTION AT E∼ 3.5 KEVAndromeda (M31) (Boyarsky et al. 2014a [1402.4119] )
JEROEN FRANSE | INSTITUUT LORENTZ & LEIDEN OBSERVATORY | TAUP 2015, TORINO, SEPT 9 2015 5 / 14
| DETECTIONS
DETECTIONS OF THE UNIDENTIFIED 3.5 KEV LINE
BOYARSKY ET AL. 2014A,B [1402.4119, 1408.4388]M31 galaxy XMM-Newton, center & outskirts 4.4σPerseus cluster XMM-Newton, outskirts only
Blank sky XMM-Newton No detection
BULBUL ET AL. 2014 [1402.2301]
73 clusters XMM-Newton (MOS & PN),centers only, up to z = 0.4 5σ & 4σPerseus cluster Chandra, center only 3.5σ
JEROEN FRANSE | INSTITUUT LORENTZ & LEIDEN OBSERVATORY | TAUP 2015, TORINO, SEPT 9 2015 6 / 14
| LINE ORIGIN
INSTRUMENTAL ORIGIN?
Instrumental origin unlikely
Detected in 4 different detectorsLine redshifts correctly with sourcesNot detected in blank sky dataset
JEROEN FRANSE | INSTITUUT LORENTZ & LEIDEN OBSERVATORY | TAUP 2015, TORINO, SEPT 9 2015 7 / 14
| LINE ORIGIN
ATOMIC LINE?
Unlikely: can not explain consistently all observations
Bulbul et al. 2014
M31 line is stronger than other atomic emissionCLUSTERS need anomalous line ratios of a factor ∼ 20−30
JEROEN FRANSE | INSTITUUT LORENTZ & LEIDEN OBSERVATORY | TAUP 2015, TORINO, SEPT 9 2015 8 / 14
| LINE ORIGIN
DARK MATTER DECAY?
The line flux should be proportional to mass / distance2
JEROEN FRANSE | INSTITUUT LORENTZ & LEIDEN OBSERVATORY | TAUP 2015, TORINO, SEPT 9 2015 9 / 14
| LINE ORIGIN
DARK MATTER DECAY?
The line flux should be proportional to mass / distance2
JEROEN FRANSE | INSTITUUT LORENTZ & LEIDEN OBSERVATORY | TAUP 2015, TORINO, SEPT 9 2015 9 / 14
| LINE ORIGIN
DARK MATTER DECAY?
The line flux should be proportional to mass / distance2
JEROEN FRANSE | INSTITUUT LORENTZ & LEIDEN OBSERVATORY | TAUP 2015, TORINO, SEPT 9 2015 9 / 14
| LINE ORIGIN
GALACTIC CENTER
Expect large signal from GC → “easy” cross-check
JEROEN FRANSE | INSTITUUT LORENTZ & LEIDEN OBSERVATORY | TAUP 2015, TORINO, SEPT 9 2015 10 / 14
| LINE ORIGIN
GALACTIC CENTER
Boyarsky et al. 2014b [1408.4388]
JEROEN FRANSE | INSTITUUT LORENTZ & LEIDEN OBSERVATORY | TAUP 2015, TORINO, SEPT 9 2015 11 / 14
| LINE ORIGIN
GALACTIC CENTER
Boyarsky et al. 2014b [1408.4388]
JEROEN FRANSE | INSTITUUT LORENTZ & LEIDEN OBSERVATORY | TAUP 2015, TORINO, SEPT 9 2015 11 / 14
| NEW & FUTURE WORK
MORE PERSEUS
Preliminary 1 Ms with Suzaku, 3σ detection in the center
Franse, Bulbul et al. (in prep)
JEROEN FRANSE | INSTITUUT LORENTZ & LEIDEN OBSERVATORY | TAUP 2015, TORINO, SEPT 9 2015 12 / 14
| NEW & FUTURE WORK
NEXT: LOTS OF DRACO
We have been awarded 1.4 Ms of XMM observations ofthe Draco dwarf galaxy this year
Nearby, dark matter dominated objectHighest expected signal of all dwarf galaxies(Geringer-Sameth+ 2014, Lovell+ 2014)Very gas-poor (do not expect any atomic lines)We will be able to confirm or deny the DM origin ofthe 3.5 keV line somewhere in 2016.
JEROEN FRANSE | INSTITUUT LORENTZ & LEIDEN OBSERVATORY | TAUP 2015, TORINO, SEPT 9 2015 13 / 14
| NEW & FUTURE WORK
DRACO DSPH OBSERVATION PROJECTIONS
1
10
0.01 0.1
Lin
e flu
x, 10
-6 p
hoto
ns c
m-2
s-1
Projected DM mass density, MSun/pc2
GC
M31
Perseus
Blank-skyBu
lbul
et a
l. (2
014)
Stac
ked
dSph
bou
nd
τ DM =
15.
6 x 1
027 s
ec
τ DM =
2.1
x 10
27 sec
1
10
0.01 0.1
Lin
e flu
x, 10
-6 p
hoto
ns c
m-2
s-1
Projected DM mass density, MSun/pc2
GC
M31
Perseus
Blank-skyBu
lbul
et a
l. (2
014)
Stac
ked
dSph
bou
nd
τ DM =
15.
6 x 1
027 s
ec
τ DM =
2.1
x 10
27 sec
1
10
0.01 0.1
Lin
e flu
x, 10
-6 p
hoto
ns c
m-2
s-1
Projected DM mass density, MSun/pc2
GC
M31
Perseus
Blank-skyBu
lbul
et a
l. (2
014)
Stac
ked
dSph
bou
nd
τ DM =
15.
6 x 1
027 s
ec
τ DM =
2.1
x 10
27 sec
1
10
0.01 0.1
Lin
e flu
x, 10
-6 p
hoto
ns c
m-2
s-1
Projected DM mass density, MSun/pc2
GC
M31
Perseus
Blank-skyBu
lbul
et a
l. (2
014)
Stac
ked
dSph
bou
nd
τ DM =
15.
6 x 1
027 s
ec
τ DM =
2.1
x 10
27 sec
JEROEN FRANSE | INSTITUUT LORENTZ & LEIDEN OBSERVATORY | TAUP 2015, TORINO, SEPT 9 2015 14 / 14
PARAMETER SPACE
JEROEN FRANSE | INSTITUUT LORENTZ & LEIDEN OBSERVATORY | TAUP 2015, TORINO, SEPT 9 2015 14 / 14
IntroductionDetectionsLine OriginNew & Future WorkAppendix