NewDark
Earth-Scattering of Dark Matter: from sub-GeV Dark Matter to - - PowerPoint PPT Presentation
Earth-Scattering of Dark Matter: from sub-GeV Dark Matter to - - PowerPoint PPT Presentation
Earth-Scattering of Dark Matter: from sub-GeV Dark Matter to WIMPzillas Bradley J. Kavanagh LPTHE - Paris VI Based (partly) on arXiv:1611.05453 with Riccardo Catena and Chris Kouvaris AmsterDark@GRAPPA - 24th May 2017
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Direct Detection Landscape
10−1 100 101 102 103 104
mχ [GeV]
10−48 10−47 10−46 10−45 10−44 10−43 10−42 10−41 10−40 10−39 10−38 10−37 10−36
σSI
p [cm2]
8B
LUX (IDM-2016) CDMSlite (2015) CRESST-II (2015) Xenon1T (2017) Xe Neutrino Floor (O’Hare 2016)
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Direct Detection Landscape
10−1 100 101 102 103 104
mχ [GeV]
10−48 10−47 10−46 10−45 10−44 10−43 10−42 10−41 10−40 10−39 10−38 10−37 10−36
σSI
p [cm2]
8B
LUX (IDM-2016) CDMSlite (2015) CRESST-II (2015) Xenon1T (2017) Xe Neutrino Floor (O’Hare 2016)
Sub-GeV DM
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Direct Detection Landscape
10−1 100 101 102 103 104
mχ [GeV]
10−48 10−47 10−46 10−45 10−44 10−43 10−42 10−41 10−40 10−39 10−38 10−37 10−36
σSI
p [cm2]
8B
LUX (IDM-2016) CDMSlite (2015) CRESST-II (2015) Xenon1T (2017) Xe Neutrino Floor (O’Hare 2016)
Sub-GeV DM WIMPzillas
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
0.1 1 10 100 300
mχ [GeV]
10−46 10−45 10−44 10−43 10−42 10−41 10−40 10−39 10−38 10−37 10−36 10−35 10−34
ρ0.3 σp
SI [cm2]
LUX CRESST-II p = 5 % p = 10% p = 1%
DD Landscape - Sub-GeV DM
CRESST-II [1509.01515] LUX [1608.07648] + many others…
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
0.1 1 10 100 300
mχ [GeV]
10−46 10−45 10−44 10−43 10−42 10−41 10−40 10−39 10−38 10−37 10−36 10−35 10−34
ρ0.3 σp
SI [cm2]
LUX CRESST-II p = 5 % p = 10% p = 1%
DD Landscape - Sub-GeV DM
CRESST-II [1509.01515] LUX [1608.07648] + many others…
Focus on this region
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Direct Detection of DM (in space?)
χ
Detector Unscattered (free) DM: f0(v)
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Astrophysics of DM (the simple picture)
Standard Halo Model (SHM) is typically assumed: isotropic, spherically symmetric distribution of particles with . Leads to a Maxwell-Boltzmann (MB) distribution (in the lab frame): ρ(r) ∝ r−2 fLab(v) = (2πσ2
v)−3/2 exp
- −(v − ve)2
2σ2
v
- Θ(|v − ve| − vesc)
[But see e.g. 1705.05853]
f(v) = v2
- f(v) dΩv
This is our ‘free’ distribution: f0(v)
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Direct Detection of DM on Earth
χ
Detector Perturbed/scattered DM: But DM scattering in the Earth can distort the velocity distribution
˜ f(v)
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Earth-Scattering - Attenuation
χ
Detector Previous calculations usually only consider DM attenuation
Kouvaris & Shoemaker [1405.1729,1509.08720] DAMA [1505.05336] Zaharijas & Farrar [astro-ph/0406531]
f(v) → f0(v) − fA(v)
Attenuation of DM flux:
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Earth-Scattering - Deflection
χ
Detector
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Emken, Kouvaris & Shoemaker [1702.07750] (see later)
Earth-Scattering - Deflection
χ
Detector
Collar & Avignone [PLB 275, 1992 and others]
Considered in early Monte Carlo simulations… Can treat (without MC) in the ‘single scatter’ approximation…
λ RE
Assuming DM mean free path As well as more recent ones… Can be very important for light DM.
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
˜ f(v) = f0(v) − fA(v) + fD(v) Earth-Scattering
Detector Total DM velocity distribution:
χ
altered flux, daily modulation, directionality…
λ RE
Assuming DM mean free path Consider both attenuation and deflection in an analytic framework (‘Single scatter’) Consider non-standard DM-nucleon interactions (e.g. NREFT)
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
deff,i = 1 ¯ ni
- AB
ni(r)dl ¯ λi(v)−1 = ¯ ni σ(v)
Attenuation
Detector
A B
v = (v, cos θ, φ) f0(v) − fA(v) = f0(v) exp
- −
species
- i
deff,i(cos θ) ¯ λi(v)
- Sum over 8 most abundant elements in the Earth: O, Si, Mg, Fe, Ca, Na, S, Al
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Effective Earth-crossing distance
Most scattering comes from Oxygen (in the mantle) and Iron (in the core)
0.0 0.2 0.4 0.6 0.8 1.0 r/RE 0.0 0.5 1.0 1.5 2.0 n(r) [cm−3] ×1023
Oxygen Iron
NB: little Earth-scattering for spin-dependent interactions
π/4 π/2 θ 0.0 0.2 0.4 0.6 0.8 1.0 1.2 ¯ n deff(θ) [cm−2] ×1032
Oxygen Iron
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Deflection
v = (v, cos θ, φ)
Detector
A B C
v = (v, cos θ, φ) ¯ λi(v)−1 = ¯ ni σ(v)
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Deflection
v = (v, cos θ, φ)
Detector
A B C
v = (v, cos θ, φ) ¯ λi(v)−1 = ¯ ni σ(v) κi = v/v fD(v) =
species
- i
- d2ˆ
v deff,i(cos θ) λi(κiv) (κi)4 2π f0(κiv, ˆ v)Pi(cos α)
[Detailed calculation in the paper]
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Deflection
v = (v, cos θ, φ)
Detector
A B C
v = (v, cos θ, φ) ¯ λi(v)−1 = ¯ ni σ(v) κi = v/v fD(v) =
species
- i
- d2ˆ
v deff,i(cos θ) λi(κiv) (κi)4 2π f0(κiv, ˆ v)Pi(cos α)
Depends on total cross section Depends on differential cross section
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Deflection
v = (v, cos θ, φ)
Detector
A B C
v = (v, cos θ, φ) ¯ λi(v)−1 = ¯ ni σ(v) κi = v/v fD(v) =
species
- i
- d2ˆ
v deff,i(cos θ) λi(κiv) (κi)4 2π f0(κiv, ˆ v)Pi(cos α)
Depends on total cross section Depends on differential cross section
Focus on low mass DM:
mχ = 0.5 GeV
Fix couplings to give 10% probability of scattering in the Earth
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
DM deflection distribution
P(cos α) = 1 σ dσ dER dER d cos α
- α
(α)
- χ =
- α
(α)
- χ =
Forward Backward Standard SI interaction
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
- α
(α)
- χ =
DM deflection distribution
P(cos α) = 1 σ dσ dER dER d cos α O12 = Sχ · ( SN × v⊥) ⇒ d dER ∼ ER v2 O1 = 1 ⇒ dσ dER ∼ 1 v2 O8 = Sχ · v⊥ ⇒ d dER ∼ (1 − mN ER 2µ2
χN v2 )
Forward Backward Standard SI interaction Standard SI interaction
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Deflection
v = (v, cos θ, φ)
Detector
A B C
v = (v, cos θ, φ) ¯ λi(v)−1 = ¯ ni σ(v) κi = v/v fD(v) =
species
- i
- d2ˆ
v deff,i(cos θ) λi(κiv) (κi)4 2π f0(κiv, ˆ v)Pi(cos α)
Depends on total cross section Depends on differential cross section
Now we have everything we need!
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
EARTHSHADOW Code
EARTHSHADOW code is available online at: github.com/bradkav/EarthShadow Including routines, numerical results, plots and animations…
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Results
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 ˜ f(v, γ) [10−3 km/s]
Operator O1 − mχ = 0.5 GeV
Free γ = 0 γ = π/2 γ = π
100 200 300 400 500 600 700 800 v [km/s] 0.7 0.8 0.9 1.0 1.1 ˜ f(v, γ)/f0(v)
Speed Distribution - Operator 1
Detector
Calculate DM speed distribution after Earth scattering: ve ˜ f(v, γ)
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Comparison with Monte-Carlo
http://cp3-origins.dk/site/damascus
Monte-Carlo results from the DaMaSCUS code
[Emken & Kouvaris - paper appearing soon]
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Comparison with Monte-Carlo
http://cp3-origins.dk/site/damascus
Monte-Carlo results from the DaMaSCUS code
[Emken & Kouvaris - paper appearing soon]
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Speed Distribution - Operator 1
Detector
Calculate DM speed distribution after Earth scattering: ve
100 200 300 400 500 600 700 v [km/s]
π 4 π 2 3π 4
π γ = cos1(hˆ vχi · ˆ rdet)
- 1 %
- 10 %
- 5 %
- 1 %
1 %
Operator O1 mχ = 0.5 GeV
- 30%
- 20%
- 10%
0% 10% 20% 30%
Percentage change in speed dist. ˜ f(v, γ)
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Speed Distribution - O1 vs O8
Detector
100 200 300 400 500 600 700 v [km/s]
π 4 π 2 3π 4
π γ = cos1(hˆ vχi · ˆ rdet)
- 1 %
- 10 %
- 5 %
- 1
% 1 %
Operator O1 mχ = 0.5 GeV
- 30%
- 20%
- 10%
0% 10% 20% 30%
100 200 300 400 500 600 700 v [km/s]
π 4 π 2 3π 4
π γ = cos1(hˆ vχi · ˆ rdet)
- 1 %
- 2
5 %
- 10 %
- 5 %
- 1 %
1 % 5 %
Operator O8 mχ = 0.5 GeV
- 30%
- 20%
- 10%
0% 10% 20% 30%
Operator 8 - preferentially forward deflection
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Speed Distribution - O1 vs O12
Detector
100 200 300 400 500 600 700 v [km/s]
π 4 π 2 3π 4
π γ = cos1(hˆ vχi · ˆ rdet)
- 1 %
- 10 %
- 5 %
- 1
% 1 %
Operator O1 mχ = 0.5 GeV
- 30%
- 20%
- 10%
0% 10% 20% 30%
Operator 12 - preferentially backward deflection
100 200 300 400 500 600 700 v [km/s]
π 4 π 2 3π 4
π γ = cos1(hˆ vχi · ˆ rdet)
- 50 %
- 25 %
- 10 %
- 5
%
- 1 %
1 % 5 % 1 %
Operator O12 mχ = 0.5 GeV
- 30%
- 20%
- 10%
0% 10% 20% 30%
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Γout =
- v·r>0
d2r
- d3v ˜
f(v, r) (v · r)
Sanity check
Compare rate of DM particles entering the Earth… Γin = πR⊕v …and rate of DM particle leaving the Earth…
Detector
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 ˜ f(v, γ) [10−3 km/s]
Operator O1 − mχ = 0.5 GeV
Free γ = 0 γ = π/2 γ = π
100 200 300 400 500 600 700 800 v [km/s] 0.7 0.8 0.9 1.0 1.1 ˜ f(v, γ)/f0(v)
Event Rate
Calculate number of signal events in a CRESST-II like experiment, with and without the effects of Earth-Scattering, and . Npert Nfree Scattering predominantly with Oxygen and Calcium. DM particles within of the energy threshold 3 σE Eth ∼ 300 eV
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Mapping the CRESST-II Rate
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Operator 1 - isotropic deflection
LNGS - Operator 1
LNGS - Gran Sasso Lab, Italy
6 12 18 24 time [hours] 0.9 1.0 1.1 1.2 Npert/Nfree LNGS (42.5 N)
- Atten. only
Atten.+Defl. O1
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Operator 8 - forward deflection
LNGS - Operator 8
LNGS - Gran Sasso Lab, Italy
6 12 18 24 time [hours] 0.9 1.0 1.1 1.2 Npert/Nfree LNGS (42.5 N)
- Atten. only
Atten.+Defl. O1 O8
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
LNGS - Operator 12
LNGS - Gran Sasso Lab, Italy
6 12 18 24 time [hours] 0.9 1.0 1.1 1.2 Npert/Nfree LNGS (42.5 N)
- Atten. only
Atten.+Defl. O1 O8 O12
Operator 12 - backward deflection
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Operator 1 - isotropic deflection
6 12 18 24 time [hours] 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 Npert/Nfree SUPL (37.1 S)
O1 O8 O12
SUPL - Operator 1
SUPL - Stawell Underground Physics Lab, Australia
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Around the world
6 12 18 24 time [hours] 0.9 1.0 1.1 1.2 Npert/Nfree LNGS (42.5 N)
- Atten. only
Atten.+Defl. O1 O8 O12
6 12 18 24 time [hours] 0.9 1.0 1.1 1.2 Npert/Nfree CJPL (28.2 N)
O1 O8 O12
6 12 18 24 time [hours] 0.8 0.9 1.0 1.1 1.2 Npert/Nfree INO (9.7 N)
O1 O8 O12
6 12 18 24 time [hours] 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 Npert/Nfree SUPL (37.1 S)
O1 O8 O12
India-based Neutrino Observatory China Jinping Lab
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Implications of Earth-Scattering
Smoking gun signature: daily modulation + location dependence could confirm DM nature Possibility to distinguish different interactions with different amplitude and phase of modulation Careful calculation (including deflection and attenuation) in the ‘single-scatter’ regime
6 12 18 24 time [hours] 0.9 1.0 1.1 1.2 Npert/Nfree LNGS (42.5 N)
- Atten. only
Atten.+Defl. O1 O8 O12
BJK, Catena & Kouvaris [1611.05453]
EARTHSHADOW code available online to include these effects: github.com/bradkav/EarthShadow
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
WIMPzillas!
PRELIMINARY
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Direct Detection Landscape - zoomed out
Mack, Beacom & Bertone [0705.4298] Albuquerque & Baudis [astro-ph/0301188]
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Direct Detection Landscape - zoomed out
Mack, Beacom & Bertone [0705.4298] Albuquerque & Baudis [astro-ph/0301188]
Earth’s heat flow from DM capture + annihilation
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Direct Detection Landscape - zoomed out
Mack, Beacom & Bertone [0705.4298] Albuquerque & Baudis [astro-ph/0301188]
Assume e.g. asymmetric DM: no heat flux from annihilation
Focus on this region
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Earth-scattering for super-heavy DM
Deflection of DM (per scatter) goes as Can show that
mA/mχ 1 v⊥(t)2 ∼ σnA m2
A
m2
χ
v4
0t v2
Deflection is almost always negligible Only need to consider stopping of ultra-heavy DM:
dv dx = −vσSI
p species
- i
ni(r) mi mχ
- A4
i Ci(v)
‘Correction factor’ due to nuclear form factors
Solve to find final DM speed given initial DM speed and incoming direction :
vi vf ˆ v vf = φ(vi, ˆ v)
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Distribution of DM reaching the detector with velocity :
Earth-stopping for super-heavy DM
χ
Detector
vf
is the initial velocity the particle must have had
˜ f(vf) = f0(φ−1(vf, ˆ v), ˆ v) vi = φ−1(vf, ˆ v)
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Preliminary Results
Consider scattering only from Silicon in the Earth, and a detector at a depth of ~11m.
CDMS I at the Stanford Underground Facility [astro-ph/0203500] From below From above
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Preliminary Results
Consider scattering only from Silicon in the Earth, and a detector at a depth of ~11m.
CDMS I at the Stanford Underground Facility [astro-ph/0203500] 10 keV CDMS I threshold Assume on average that the DM flux comes from about 40 degrees off vertical
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Preliminary Results
Mack, Beacom & Bertone [0705.4298] Albuquerque & Baudis [astro-ph/0301188]
Possible gain of about 3 orders of magnitude in cross section
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Caveats
Need to include all Earth elements (but expect Silicon to dominate) Need to perform full careful rate calculation Need to take into account energy losses in the detector shielding (e.g. 1cm thick lead shield) Expect ~2 orders of magnitude improvement in limits (rather than 3),
- nce I’ve calmed down and done everything properly…
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Direct Detection Landscape
10−1 100 101 102 103 104
mχ [GeV]
10−48 10−47 10−46 10−45 10−44 10−43 10−42 10−41 10−40 10−39 10−38 10−37 10−36
σSI
p [cm2]
8B
LUX (IDM-2016) CDMSlite (2015) CRESST-II (2015) Xenon1T (2017) Xe Neutrino Floor (O’Hare 2016)
Sub-GeV DM WIMPzillas Still interesting parts of the landscape where Earth-scattering can be explored…
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM
Backup Slides
Bradley J Kavanagh (LPTHE, Paris) AmsterDark@GRAPPA - 24th May 2017 Earth-scattering of DM