Transcript フェルミ衛星が捉えた 未同定ガンマ線源のX線探査

すざくによる高銀緯
フェルミ未同定天体のX線探査
(submitted to ApJ)
2010/09/24 日本天文学会 2010年 秋季年会 @金沢大学
前田洸登 （早大理工）
片岡淳，中森健之（早大），真喜屋龍，戸谷友則（京大）
金井義和，河合誠之（東工大），Lukasz Stawarz，田中康之，
佐藤理江，高橋忠幸（ISAS/JAXA），C. Cheung（NASA/GSFC），
D. Donato，N. Gehrels（CRESST），P. Saz Parkinson（SCIPP）
（271 sources）
CGRO/EGRET all-sky g-ray Survey
EGRET All-Sky Gamma-Ray Survey ( > 100MeV)
● UnID : 170 sourcesCredit: EGRET team
640 out of 1451 sources are still UnID
Motivation of Suzaku observation

To survey a new-type g-ray source
Bright in the long term, but still unID
 Extragalactic, but Not AGN
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
Source selection (3 months Fermi obs.)
Bright unID source (EGRET and 0FGL)
 At high Galactic latitude (|b| > 10 [deg])
 No temporal variability

Observed UnID Fermi/LAT
Object
1FGL J1231.1-1410
1FGL J1333.2+5056
1FGL J1311.7-3429
|b|=10 [deg]
1FGL J2017.3+0603
Fermi/LAT Gamma-ray Image of 1-year Observation (100MeV - 300GeV)
Credit: NASA/DOE/Fermi LAT Collaboration
1FGL J1231.1-1410
1FGL J1311.7-3429
Results of Suzaku Follow-up Observation
1FGL J1333.2+5056
- Too much complicated
- Run off the edge of FOV
1FGL J2017.3+0603
1FGL J1231.1-1410 X-ray Image


Dec.[deg]

Brightest g-ray
source of 4 unIDs
EGRET unID
(Radio) MSP PSR
J1231-1411


PSR J1231-1411
(P=3.68ms,d=0.4kpc)
Ransom et al. 2010
X-ray position is
consistent with g-ray
& radio position
Suzaku XIS0+3 (0.4 - 10 keV)
R.A.[deg] (NXB subtracted, exposure & vignetting corrected)
X-ray Spectrum Analysis
(Black:XIS0+3,Red:XIS1)
wabs * blackbody
wabs ( blackbody + powerlaw )
NH=0 consistent
NH=0 consistent
Γ ~ 1.8
Residuals remain
(> 2 keV)

2
d.o.f  134 . 7 34
kT ~ 0.16 keV
improved

2
d.o.f.  56 . 2 32
Additional PL component is necessary!
(significance level >99%)
1FGL J1231.1-1410
nFn multi-wavelength SED
Bright g-ray flux & blackbody + PL is similar
to the spectral structure of Geminga pulsar
Multi-wavelength SED of Geminga pulsar
Credit:: D. J. Thompson (2004)
1FGL J1311.7-3429 X-ray Image
Dec.[deg]
 EGRET unID
 Two X-ray sources
factor
10
(a) src A
X-ray flare
20 ks
(b) src B
steady flux
Suzaku XIS0+3 (0.4 - 10 keV)
R.A.[deg] (NXB subtracted, exposure & vignetting corrected )
1FGL J1311.7-3429
nFn multi-wavelength SED
No pulse detection (g-ray, radio)
Remain uncertain (not typical blazar)
?
QHB (QSO Hosted Blazar) ?!
1FGL J2017.3+0603 X-ray Image


Fermi unID
(Radio) MSP PSR
J2017+0603:
Dec.[deg]



R.A.[deg]
Cognard et al. 2010
(P=2.9ms)
g-ray pulsation
CLASS
J2017+0603:
(z=1.74 blazar)
Suzaku XIS0+3 (0.4 - 10 keV)
(NXB subtracted, exposure & vignetting corrected)
1FGL J2017.3+0603
nFn multi-wavelength SED
CLASS J2017+0603
X - ray 90% Upper Limit
S 2  8 keV  2 . 61  10
14
PSR J2017+0603
[erg cm
2
1
s ]
Summary

Our Suzaku observation findings




1FGL J1231.1-1410 :
newly detected PL component of MSP
1FGL J1311.7-3429 :
detected variable X-ray source
but still uncertain (QHB blazar?)
1FGL J2017.3+0603 :
only detected a blazar and not a pulsar
in X-ray (give a pulsar upper-limit)
1FGL J1333.2+5056 :
too much complicated
due to large localization error
Next X-ray observations (AO-5)