Weak-charged WIMP
Shigeki Matsumoto (Kavli IPMU)
Collaborators: Members in IPMU WIMP PROJECT

Weak-charged WIMP recently attracts many attentions.
We introduce the WIMP focusing on following questions:
Why it is attractive and how it can be tested in future.

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Dark matter hypotheses
Particle dark matter

Mass
10–22 eV1019 GeVl = 2p/mv < Gal. size

l = 2p/m ~ 2m/Mpl2

1040 gm < Gal. mass

Experimental/Observational anomalies
Dark matter hypotheses
ADMSterile nSIMPFIMPAxion

WIMP

Fuzzy DMpBH

Motivations from new physics models

Phenomenological test of each ansatz. (Present S. & Future P)

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WIMP hypothesis“Dark matter is a massive, stable and electrically neutral particle, andwas in a thermal equilibrium with SM particles in the early universe.”
From Neff

WIMP dark matter

From unitarity

GeV
10 5

10 –3

There are many types of WIMP, depending on those quantum numbers.
 Classification of WIMP in terms of its spin and isospin!
After its spin fixed,WIMP

Singlet-like

Weak-charged

Mixed

Unexplored well.
Good motivation?

Vert attractive!!!

being excluded bydirect detections,Weak-charged WIMP (Triplet WIMP)

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DM physics governed by SU(2)L[Z2 symmetry imposed]

One new physics parameter MT

Theoretical motivation … Anomaly mediated SUSY breaking scenario
It is know to be the simplest SUSY breaking model consistent with cosmology!

MSSM

Simplest mediation
w/o singlet SUSY✓ Split SUSY spectrum predicted.

TeV
100

Sfermions, Higgsino
Heavy Higgs bosons

1Gauginos✓ Wino (Triplet WIMP) is the LSP.
✓ Its mass is predicted to be 3TeV!
✓ mLSP is O(1)TeV  MSUSY is O(100)TeV.
✓ Hiss mass is predicted to be 125GeV.
✓ Avoid serious SUSY flavor problems.
✓ Free from any cosmological problems.

LSP = Wino!!

Weak-charged WIMP (Triplet WIMP)

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DM physics governed by SU(2)L[Z2 symmetry imposed]

One new physics parameter MT

Phenomenological motivation … Anti-proton flux observed at AMS-02.
It is consistent with BG, but there is a trend of the deviation at E > 100GeV.

AMS-02+ Wino contribution
Secondary –p[Ibe, S. M., Shirai, T. Yanagida, 2015]1504.04276

If we include the Triplet WIMP contribution, the fitting becomes better.
(There is no new physics parameters we can vary, for mT = 3TeV.)

How we can test the triplet WIMP?
Search @ Collider experiments
Current limit (13TeV LHC) mT < 460GeV
Future-expected limit (HL-LHC) mT < 1TeV
Disappearing charged track search

Future-expected limit (100TeV pp)
 mT < 3TeV

Search @ Direct detections[Hisano, Ishiwata, Nagata, 2015]

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How we can test the triplet WIMP?
Search @ Indirect detections

dSphgThermal region Milky Way

Sommerfeld enhancement!
S.M.,
Nojiri (2005)][Hisano, S.[Hisano,M., Nojiri,2004]

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How we can test the triplet WIMP?
Search @ Indirect detections

PFSdSphg

Thermal region Milky Way

CTA

Sommerfeld enhancement!
S.M.,
Nojiri (2005)][Hisano, S.[Hisano,M., Nojiri,2004]

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How we can test the triplet WIMP?

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Theory side

Observation side

Collisionless Boltzmann eq.

Astrophysical observations⇓Photometric data:
Locations of the memberstars, etc. are obtained.

Jean’s equation derived.

Distribution of member stars[f(x, v) of the member stars]↕

DM mass distribution [r(x)]Bayesiananalysis

Spectroscopy data:
Velocity of the memberstars, etc. are obtained.

DM profile r(x) obtained.  J-factor is evaluated as the pdf of the analysis.
Systematic errors associated with the J-factor determination✔ The systematic error coming from the non-spherical nature of dSphs.
✔ The systematic error coming from the contamination of foreground stars.
✔ The systematic error coming from binaries composed of member stars.
✔ The systematic error coming from asymmetry of velocity dissipations.

How we can test the triplet WIMP?
Draco

Several ways to deal with the contamination:
1. Cut-based identification of member stars,
which is used for the most of UF dSphs.
2. EM method to put a membership probability,
which is currently used for CL dSphs.

[M. Walker, et. al. 2015]

3. KI method (that we have recently proposed.),which is based on the one LHC is adopting.

8/8How we can test the triplet WIMP?
Draco

SR

Several ways to deal with the contamination:

CR

1. Cut-based identification of member stars,
which is used for the most of UF dSphs.
2. EM method to put a membership probability,
which is currently used for CL dSphs.

[M. Walker, et. al. 2015]

3. KI method (that we have recently proposed.),which is based on the one LHC is adopting.

Simultaneous fitting →FG stars

Member stars

8/8How we can test the triplet WIMP?
Draco

SR

Several ways to deal with the contamination:

CR

1. Cut-based identification of member stars,
which is used for the most of UF dSphs.
2. EM method to put a membership probability,which is currently used for CL dSphs.

[M. Walker, et. al. 2015]

OursEM’sNaïve

3. KI method (that we have recently proposed.),which is based on the one LHC is adopting.

CL dSphs

Input
Input

Mock (i > 21)✓ KI method well reproduces the input.
The same conclusion for UF dSphs too.
✓ EM method also reproduces the input,
though some systematic errors remain.

✓ Cut-based one always overestimatesthe input. The trend becomes moresizable for fainter dSphs UF dSphs).
Remember the nightmare of Segue 1!

8/8How we can test the triplet WIMP?
Draco

SR

Several ways to deal with the contamination:

CR

1. Cut-based identification of member stars,
which is used for the most of UF dSphs.
2. EM method to put a membership probability,
which is currently used for CL dSphs.

[M. Walker, et. al. 2015]

3. KI method (that we have recently proposed.),which is based on the one LHC is adopting.

UF dSphs

Ours
EM’sNaïve

✓ KI method well reproduces the input.
The same conclusion for UF dSphs too.
✓ EM method also reproduces the input,though some systematic errors remain.

Input
Input

Mock (i > 21, 21.5, 22)✓ Cut-based one always overestimatesthe input. The trend becomes moresizable for fainter dSphs UF dSphs).
Remember the nightmare of Segue 1!

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Summary•

WIMP which has a weak charge attracts many attentions after
the Higgs discovery. Only indirect dark matter detections allow
us to detect the WIMP in near future, for it has O(1)TeV mass.

•Among various indirect dark matter detections, the observationof gamma-rays from dSphs are the most robust one to detect
the signal of, or to put a constraint on the TeV scale WIMP.

•It is important to predict the signal flux for this purpose, andit requires the careful estimation of J-factors involving thetreatment of FG star contamination and the DM & stellar nonsphericity, etc. Future spectroscopic measurements such as thePFS in the SuMIRe project will play a very important role!

Backup (Triplet-like Fermion WIMP)
Field Theory Lagrangian of WIMP
|yon(r)|↓

Non-relativistic expansion andintroducing a ‘composite’ fielddescribing WIMP 2-body states.

w/o V(r)|yoff(r)|↓r0

The Schrodinger eq. is obtainedas EOM of the composite field.

[-∇2/m + V(r)]y(r) = 0

w/ V(r)Wino↓

WIMP Annihilation cross section
is obtained by the formula:(sv)on = (|yon(0)|2/|yoff(0)|2) (sv)off(sv)off(sv)on↓

Weak long-range force increase
the wave function at origin, forit acts as a attractive force!!!

[J. Hisano, S. M., M. Nagai, M. Nojiri,
O. Saito, M. Senami, 2004-2007.]