γ線スカイサーベイと銀河団カタログを用いたダークマターシグナルの探査
Daiki Hashimoto, Atsushi J. Nishizawa,
Hiroyuki Tashiro, Kenji Hasegawa (Nagoya University)
Masato Shirasaki (NAOJ)
Shunsaku Horiuchi, Oscar Macias (Virginia Tech)

The gamma-ray sky survey by Fermi Gamma-ray Space Telescope

Image Credit: NASA/DOE/Fermi LAT Collabora:on

Extragalac(c Gamma-ray Background(EGB)…remains of the total measured gamma-ray emission aFer the subtrac(onof the resolved sources and of the diﬀuse Galac(c foregrounds.

Introduc)onObserva(onModelResultIf dark maKer mass is around GeV order...
Annihila'on process (example processes)
DMγ

DMγ

Decay process
DMγγ

From gamma-ray sky survey and theore(cal predic(on,dark ma.er proper)es can be restricted.
Introduc)on

Observa(onModelResult

S. Ando, E. Komatsu （2013）
Observa'onal data :gamma-ray backgroundby Fermi GRST sky survey
Theore'cal es'ma'on :halo mass func(on :EPS
annihila(on process(at dark maKer mass of 10GeV)

Introduc)on

Observa(onModelResult

PlanckSZ (N=1653)

redMaPPer (N=26350)

WHL12 (N=39668)(1〜10GeV)

Branchini et al.(2017)

Introduc(onObserva)on

Model

Result

In this work...

・Fermi GRST gamma-ray sky survey

・HSC（Hyper Suprime-Cam）cluster catalog
HSC cluster catalog (CAMIRA catalog)

Introduc)on

Observa(onModelResult3/11

HSC

redshiF and posi:on of each cluster+・mass assump(on : 10^14MsunFermi GRST
distribu:on of the gamma-ray intensity

obtain number count of gamma-ray photons at
each cluster posi)on with redshi@.
Introduc(onObserva)on

Model

Result4/11

Fermi map + cluster posi:ons (sample)
cluster posi)on

Stack the gamma-rayintensity at HSC
clusters posi(on↓obtain the gammaray intensity fromthese clusters
Introduc(onObserva)on

Model

Result5/11

Stack the gamma-ray
intensity map aroundeach cluster

the center of each cluster

preliminary
Introduc(onObserva)on

Model

Result5/11

Stacked images obtained from random rota(on at each cluster posi(onvariable : γ-ray energy

0.5〜1GeV
Introduc(onObserva)on

1〜3GeVModel

5〜10GeVResultStacked images obtained from random rota(on at each cluster posi(onvariable : redshi@

redshiF : 0.1〜0.3
Introduc(onObserva)on

0.3〜0.6Model

0.6〜1.1
ResultStacked images obtained from random rota(on at each cluster posi(onvariable : richnessrichness : top 500
Introduc(onObserva)on

top 1000
Model

top 2000ResultAssuming the two simple processes.
Annihila'on process
DMγ

DMγ

Decay processDMγγ

Introduc)on

Observa(onModel

Result6/11

ANNIHILATION・Adop(ng the NFW proﬁle for clusters
・Fixing a cluster mass to 10^14Msun

generated number of photonsper unit )megamma-ray a.enua)on1 / (luminosity distance)^2
Introduc(onObserva(onModel

Result

7/11

DECAY・Adop(ng the NFW proﬁle for clusters
・Fixing a cluster mass to 10^14Msun

generated number ofphotons per unit )me

1 / (luminosity distance)^2
Introduc(onObserva(ongamma-ray a.enua)on
Model

Result8/11

Introduc(onObserva(onModelResult9/11

Upper limit on annihila)on cross sec)on and decay rate

Introduc(onObserva(onModelResult

10/11✔︎ The gamma-ray intensity at a cluster posi(on and random posi(onare not signiﬁcantly diﬀerent. We need to analyze the signal more
precisely.
・ inaccuracy of evalua(on for galac(c gamma-ray foreground・ underes(ma(on for spread of signals from clusters✔︎ More clusters in future HSC will be expected which enable us todis(nguish the models (annihila(on or others).