重力波の初観測
真貝寿明（大阪工大）
http://www.oit.ac.jp/is/~shinkai/
2016年2月，LIGOが重力波を初めて検出した，と発表した

JAHOU集会2016
2016/3/13

『クーリエ・ジャポン電子版』（講談社）『ブラックホール・膨張宇宙・重力波
一般相対性理論の100年と展開』
光文社新書
2015年9月刊
http://courrier.jp/news/archives/44233/

重力の正体は？
重力の正体は？

「万有引力があるからだ」（Newton , 1687）

Mm
F =G 2rd2 x
m 2 =Fdt「時空のゆがみだ」
http://hikingartist.com/（Einstein , 1915）
一般相対性理論Rµ⌫18⇡GRgµ⌫ = 4 Tµ⌫
2c⌫⇢d2 ⇠ µd⇠d⇠µ=R⇠⌫⇢
2d⌧d⌧ d⌧秋本 祐希著，洋泉社

http://higgstan.com/2016/02/11/752

重力波

幻の発見 (1968/70)
Joseph Weber (pictured), a physicist at the University of Maryland inCollege Park, believed that gravitational waves were real. In 1969, heannounced that he had found them with a detector of his own invention: analuminium cylinder, about 2 metres long and 1 metre in diameter, that ‘rang’
when it was struck by such a wave2. His result was never replicated, andwas eventually rejected by nearly everyone except Weber himself.
Nonetheless, his work drew many other researchers into the gravitational
wave field.

68年に「２台の装置で同時に重力波信号を検出」
70年に「重力波信号はおよそ一日に三回の頻度で検出され、検出装置が銀河の中心に対して垂直方向に向いているときに検出率が高い」と発表したが，他のグループで追試されず．

Joseph Weber連星中性子星の発見 (1974)

パルサー＝中性子星
半径 10km位
質量 1.4x太陽

Arecibo, Puerto Rico

http://www.nobelprize.org/nobel̲prizes/physics/laureates/1993/illpres/discovery.html

連星中性子星の発見 (1974)

重力波を放出してエネルギーを失うので，星が近づいてゆく．

重力波の存在が間接的に確かめられた．

連星中性子星の発見 (1974)"for the discovery of a new type of pulsar, a
discovery that has opened up new
possibilities for the study of gravitation""重力についての新しい研究を開いた，新種のパルサーの発見に対して"重力波の存在が間接的に確かめられた．

重力波の存在が間接的に確かめられた．
重力波の直接観測をしたい！

連星中性子星(BNS)
連星ブラックホール(BBH)1.0

重力波の振幅 × 10

−22

ブラックホール形成の重力波波形

0.5

0.0

!0.5

!1.0

連星のインスパイラル運動からの重力波波形!25!20!15!10

時間 [ミリ秒]!50

合体の時刻

5

LIGO（レーザー干渉計重力波天文台）
Laser Interferemeter Gravitational-Wave Observatory （1992年予算承認)

https://mediaassets.caltech.edu/gwave

朝日新聞2015/11/5

LIGO（レーザー干渉計重力波天文台）
Laser Interferemeter Gravitational-Wave Observatory （1992年予算承認)

KAGRA（大型低温重力波望遠鏡）
Kamioka Gravitational wave detector, (Large-scale Cryogenic Gravitational wave Telescope)
望遠鏡の大きさ：基線長 3km
望遠鏡を神岡鉱山内に建設
地面振動が小さい岐阜県飛騨市にある神岡鉱山
鏡をマイナス250度（20K）まで冷却
熱雑音を小さくするため鏡の材質としてサファイア
光学特性に優れ、低温に冷却すると熱伝導や機械的損失が少なくなる

http://gwcenter.icrr.u-tokyo.ac.jp/plan/history

2015年8月

Hisaaki Shinkai

Seiji Kawamura
Kieran Craig
Martynov Denis重力波の波源
sources of gravitational wave
http://gwcenter.icrr.u-tokyo.ac.jp/

連星合体を予測が難しい振幅が小さい振幅が小さいターゲットに重力波は弱いのであらかじめ，波形の予測が必要
ノイズにまみれたデータに，予測した波形があるか探す（matched-ﬁltering method）

ブラックホールの合体シミュレーション

２つのブラックホールの合体と重力波放出（90年代，NCSAグループ）

ブラックホールの合体シミュレーション

NCSA-AEI group (1998)

連星中性子星(BNS)
連星ブラックホール(BBH)1.0

重力波の振幅 × 10

−22

ブラックホール形成の重力波波形

0.5

0.0!0.5!1.0

連星のインスパイラル運動からの重力波波形!25!20!15!10

時間 [ミリ秒]

!50

合体の時刻

5http://www.ligo.org/magazine/LIGO-magazine-issue-8.pdf

LIGO（レーザー干渉計重力波天文台）
Laser Interferemeter Gravitational-Wave Observatory （1992年予算承認)

https://mediaassets.caltech.edu/gwave

2015/9/16--2016/1/15
Observation run 1

2015/9/25

2016/1/11

重力波初検出を発表するライツィLIGO所長
2016年2月11日“We had detected gravitational waves.
We did it. ” (David Reitze)
https://www.youtube.com/watch?v=aEPIwEJmZyE

重力波波形を音にすると．．．

始め2回は実周波数，後の2回は聞えやすいように+400Hz
https://mediaassets.caltech.edu/gwave

www.ligo.org/magazine/LIGO-magazine-issue-8.pdf

GW100916 “Big Dog”

著者1010人
PRL 16ページ

Localization and broadband follow-up of thegravitational-wave transient GW150914
This article is under preparation by the LIGO Scientific Collaboration, the Virgo collaboration,and partner observing facilities. The full version will be posted on or after February 15, 2016. It
will describe the rapid detection and position reconstruction of the gravitational-wave signal andthe broadband follow-up campaign by 21 teams of observers, spanning radio, optical, nearinfrared, X-ray, and gamma-ray wavelengths with ground- and space-based facilities.

LALInference sky map (GCN 18858) Mollweide projection plot

600 square degrees

35

GW150914:FACTSHEETBACKGROUND IMAGES: TIME-FREQUENCY TRACE (TOP) AND TIME-SERIES( B O T T O M ) I N T H E T W O L I G O D E T E C T O R S ; S I M U L AT I O N O F B L A C K H O L E
HORIZONS (MIDDLE-TOP), BEST FIT WAVEFORM (MIDDLE-BOTTOM)

first direct detection of gravitational waves (GW) and first direct observationof a black hole binary
observed by

LIGO L1, H1

duration from 30 Hz~ 200 ms

source typeblack hole (BH) binary# cycles from 30 Hz~10

date

14 Sept 2015

peak GW strain

1 x 10-21

time

09:50:45 UTC
0.75 to 1.9 Gly
230 to 570 Mpc±0.002 fm

likely distancepeak displacement ofinterferometers arms

150 Hz, 2000 km

redshift

0.054 to 0.136

frequency/wavelength
at peak GW strain

signal-to-noise ratio

24

peak speed of BHs~ 0.6 cpeak GW luminosity

3.6 x 1056 erg s-1

false alarm prob.

< 1 in 5 million

radiated GW energy

2.5-3.5 M⊙

false alarm rate

< 1 in 200,000 yr

remnant ringdown freq.

~ 250 Hzremnant damping time

~ 4 ms

Source Masses

M⊙

total mass

60 to 70

primary BH

32 to 41

secondary BH

25 to 33

remnant BH

58 to 67

mass ratio

0.6 to 1

primary BH spin

< 0.7

secondary BH spin

< 0.9

remnant BH spin

0.57 to 0.72

signal arrival timedelay

arrived in L1 7 ms
before H1

likely sky position

Southern Hemispherelikely orientation
resolved toface-on/off~600 sq. deg.

.

.

remnant size, area

180 km, 3.5 x 105 km2

consistent withgeneral relativity?

passes all tests
performed

graviton mass bound< 1.2 x 10-22 eV

coalescence rate ofbinary black holes

2 to 400 Gpc-3 yr-1

online trigger latency~ 3 min# offline analysis pipelines5

CPU hours consumed~ 50 million (=20,000PCs run for 100 days)

papers on Feb 11, 201613

# researchers~1000, 80 institutionsin 15 countries

Detector noise introduces errors in measurement. Parameter ranges correspond to 90% credible bounds.
Acronyms: L1=LIGO Livingston, H1=LIGO Hanford; Gly=giga lightyear=9.46 x 10 12 km; Mpc=megaparsec=3.2 million lightyear, Gpc=10 3 Mpc, fm=femtometer=10 -15 m, M⊙=1 solar mass=2 x 10 30 kg

36Msun + 29 MsunのBHが合体して 62 Msun
（3 Msun分の質量が消失）
13億光年先（400 170 Mpc）
（z=0.054̶0.136）

GW150914:FACTSHEETBACKGROUND IMAGES: TIME-FREQUENCY TRACE (TOP) AND TIME-SERIES( B O T T O M ) I N T H E T W O L I G O D E T E C T O R S ; S I M U L AT I O N O F B L A C K H O L E
HORIZONS (MIDDLE-TOP), BEST FIT WAVEFORM (MIDDLE-BOTTOM)

first direct detection of gravitational waves (GW) and first direct observationof a black hole binary
observed by

LIGO L1, H1

duration from 30 Hz~ 200 mssource typeblack hole (BH) binary# cycles from 30 Hz~10date

14 Sept 2015

peak GW strain

1 x 10-21time

09:50:45 UTC0.75 to 1.9 Gly
230 to 570 Mpc±0.002 fm

likely distancepeak displacement ofinterferometers arms

150 Hz, 2000 km

redshift

0.054 to 0.136

frequency/wavelength
at peak GW strain

signal-to-noise ratio

24

peak speed of BHs~ 0.6 cpeak GW luminosity

3.6 x 1056 erg s-1

false alarm prob.

< 1 in 5 million

radiated GW energy

2.5-3.5 M⊙

false alarm rate

< 1 in 200,000 yr

remnant ringdown freq.

~ 250 Hzremnant damping time

~ 4 ms

Source MassesM⊙

total mass

60 to 70

primary BH

32 to 41

secondary BH

25 to 33

remnant BH

58 to 67

mass ratio

0.6 to 1

primary BH spin

< 0.7

secondary BH spin

< 0.9

remnant BH spin

0.57 to 0.72

signal arrival timedelay

arrived in L1 7 ms
before H1

likely sky position

Southern Hemispherelikely orientation
resolved toface-on/off~600 sq. deg.

重力波が検出された！
重力波が検出できた！
BHが存在した！
BH連星が存在した！
相対論が第0近似として正しい！

.

.

remnant size, area

180 km, 3.5 x 105 km2

consistent withgeneral relativity?

passes all tests
performedgraviton mass bound< 1.2 x 10-22 eV

coalescence rate ofbinary black holes

2 to 400 Gpc-3 yr-1

online trigger latency~ 3 min# offline analysis pipelines

5CPU hours consumed~ 50 million (=20,000PCs run for 100 days)

papers on Feb 11, 201613

# researchers~1000, 80 institutionsin 15 countries

Detector noise introduces errors in measurement. Parameter ranges correspond to 90% credible bounds.
Acronyms: L1=LIGO Livingston, H1=LIGO Hanford; Gly=giga lightyear=9.46 x 10 12 km; Mpc=megaparsec=3.2 million lightyear, Gpc=10 3 Mpc, fm=femtometer=10 -15 m, M⊙=1 solar mass=2 x 10 30 kg

東京新聞 2016/2/12

重力波が検出された！
重力波が検出できた！
BHが存在した！
BH連星が存在した！
相対論が第0近似として正しい！

毎日新聞 2016/2/13

重力波天文学で何がわかる？
対応する天体の姿
天体物理学
ブラックホールの存在する強い重力場
一般相対性理論の検証
中性子星連星合体のふるまい
原子核の状態方程式
イベント頻度・統計
星形成モデル・銀河中心ブラックホール
宇宙論パラメータ
背景重力波の存在
星形成モデル・宇宙初期モデル

重力波天文学で何がわかる？
とんでもないこと？

世の中，実は5次元．．とか

重力波天文学の幕開け

Einstein Telescope (10kmx3)

重力波が検出された！
重力波が検出できた！
BHが存在した！
BH連星が存在した！
相対論が第0近似として正しい！

LISA Pathfinder

DECIGO Pathfinder以下，バックアップPRL116（2016）061102

PRL116（2016）061102

PRL116（2016）061102

1602.03839

論文紹介

GW150924のSwiftフォロー

2016/2/14 真貝P.A. Evans +, arXiv:1602.03868 (submitted to MNRAS Lett.)
Swift follow-up of the Gravitational Wave source GW150914

結論

対応天体はなかった

P.A. Evans +, MNRAS 455(2016) 1522 [arXiv:1506.01624]
Optimisation of the Swift X-ray follow-up of Advanced LIGO
and Virgo gravitational wave triggers in 2015--16

ガンマ線バーストを探す
素早く向きを変える様子から「Swift」(和名アマツバメ)48

2015 September 14 at 09:50:45 UTʻCoherent WaveBurstʼ (cWB) pipeline for ALIGO triggered2015 September 16 at 06:39 UTThis event was announced to the EM follow-up partners
The 90% conﬁdence errore region in the initially-releasedskymap ʻLIB skymapʼ covered 750 square degrees (this was later
reduced to 600 square degrees in the ʻLALInterenceʼ skymap）

この論文ではXRT and UV/Optical telescope (UVOT; Roming et al. 2005)
Burst Alert Telescope (BAT; Barthelmy et al. 2005) data for any sign ofhard X-ray emission at the time of the trigger.
他のフォローアップ・サーチについては別の論文にまとめる予定

49

Localization and broadband follow-up of thegravitational-wave transient GW150914
This article is under preparation by the LIGO Scientific Collaboration, the Virgo collaboration,and partner observing facilities. The full version will be posted on or after February 15, 2016. It
will describe the rapid detection and position reconstruction of the gravitational-wave signal andthe broadband follow-up campaign by 21 teams of observers, spanning radio, optical, nearinfrared, X-ray, and gamma-ray wavelengths with ground- and space-based facilities.

LIB sky map (GCN 18330) Mollweide projection plot

750 square degrees

50

Localization and broadband follow-up of thegravitational-wave transient GW150914
This article is under preparation by the LIGO Scientific Collaboration, the Virgo collaboration,and partner observing facilities. The full version will be posted on or after February 15, 2016. It
will describe the rapid detection and position reconstruction of the gravitational-wave signal andthe broadband follow-up campaign by 21 teams of observers, spanning radio, optical, nearinfrared, X-ray, and gamma-ray wavelengths with ground- and space-based facilities.

LALInference sky map (GCN 18858) Mollweide projection plot

600 square degrees

51

Sun
BAT ﬁeld of view

LIB̲skymapby LVC teamon 2015 Sep 15Moon
LMC

luminosity-weighted
GWGC map

LMC

P.A. Evans +, arXiv:1602.03868

52

GW group 2015 September 16 at 06:39 UT
Sep 16 at 15:19 UT

Sep 17 at 20:12 UT
P.A. Evans +, arXiv:1602.03868

53

判定基準を4つに分けた
Rank 1: Good GW counterpart candidate.

良いGW対応候補天体 カタログの銀河に接近

Sources which lie within 200 kpc of a GWGC galaxy, and are either uncatalogued and brighter
than the 3-σ catalogue limit, or catalogued but brighter than their catalogued flux. In both cases,‘brighter than’ means that the measured and historical values (or upper limits) disagree at the5-σ level. For uncatalogued sources, the comparison is to the RASS, or to 1SXPS or the XMM
catalogues, if an upper limit from those catalogues is available and deeper than the RASS limit.
GW対応候補天体の可能性あり

Rank 2: Possible counterpart.

The criteria for this are similar to those above, except that ‘brighter’ is determined at the 3-σlevel, and there is no requirement for the source to be near a known galaxy.
Rank 3: Undistinguished source.

判定できず

Sources which are uncatalogued, but are fainter than existing catalogue limits, or consistent
with those limits at the 3-σ level. i.e. sources which cannot be distinguished from field sources.
Rank 4: Not a counterpart.

対応候補天体ではない

Sources which are catalogued, and which have fluxes consistent with (at the 3-σ level) or fainterthan their catalogued values.

P.A. Evans +, arXiv:1602.03868

54

Gravitational Wave Galaxy Catalogue (GWGC)
A list of galaxies for gravitational wave searches
Darren J White, E J Daw and V S Dhillon
CQG 28 (2011) 085016

既存の4カタログを統合
Tully Nearby Galaxy Catalog
Catalog of Neighboring Galaxies
V8k catalogue
HyperLEDA
53000個の銀河
150個のMilky Way 球状星団
100Mpc以内のもの

55

Gravitational
Gravitational Wave
Wave Galaxy
Galaxy Catalogue
Catalogue (GWGC)(GWGC)
A list of galaxies for gravitational wave searches
Darren J White, E J Daw and V S Dhillon
CQG 28 (2011) 085016

既存の4カタログを統合
Tully Nearby Galaxy Catalog
Catalog of Neighboring Galaxies
V8k catalogue
HyperLEDAP.A. Evans +,MNRAS 455(2016) 1522
[arXiv:1506.01624]

53000個の銀河
150個のMilky Way 球状星団
100Mpc以内のもの

http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=GWGC
http://vizier.nao.ac.jp/viz-bin/VizieR-256

結果

3つ見つかったが Rank 4: Not a counterpart.

対応候補天体ではない

P.A. Evans +, arXiv:1602.03868

議論と結論★XRTでは，4.7 平方度を調べた（LALInterenceの2％の領域）★合体の瞬間に，BATは，その方向を向いていなかった．時折，そのような場合でもバーストを引っ掛けるが，今回は 100secに，なし．
★BH-BHならばガンマ線バーストあるかどうか不明，しかも500Mpcであれば銀河カタログになく，「対応なし」は驚くべきことではない．
★triggerのアナウンスがされてから，15時間以内にGW-EMグループに，結果を伝えることができた．
★GWグループには，距離や質量などを添えて，もっと狭い範囲でア57
ラートを．