LISA Symposium X
LISA
Symposium X
Gainesville FL
May 21, 2014
y (
)
Sheila Dwyer (LIGO‐Hanford)
on behalf of the LIGO Scientific Collaboration
G1400149
LIGO Hanford Observatory
H1‐ in the desert (WA)
Separated by 4000 km
13 ms at the speed of light
LIGO Livingston Observatory
L1‐ in the swamp (LA)
3rd LIGO rd LIGO Construction of a 3
interferometer in interferometer in India under India planned
consideration
2
LIGO‐India
•
LIGO Laboratory is partnering with India to develop a LIGO Observatory in India
Localization without LIGO‐India
– US (LIGO Laboratory) provides components for one Advanced LIGO detector – India provides site, facility, and operating funds for LIGO‐
India through 2026
•
•
Motivation: More detectors enables multi‐messenger astronomy  better localization of GW events
astronomy better localization of GW events
Status:
– LIGO‐India identified by Indian Government as a Mega‐
science Project for 2012‐2026 period
•
Currently awaiting final approval by Government of India
– Total funding of $230M requested; approximately 1/4 in first 5 years
– Three leading Indian Laboratories and Institutes are partnering to build LIGO‐India
t i t b ild LIGO I di
– Four viable site locations within India have been identified and vetted – Current schedule has science operations beginning in 2022
Localization including LIGO‐India
3
Advanced LIGO vs. Initial LIGO
Advanced LIGO vs. Initial LIGO
15‐20 Mpc NS inspiral range 150 Mpc NS inspiral range
inspiral range 4
Displacement sen
nsitivity (log10 m/rt Hzz)
Ground and space based detectors
Ground and space based detectors
‐10
11
‐11
‐12
‐13
‐14
GWINC
NASA/ESA
Test mass separation
~109 meters
Test mass separation
~103 meters
5
Advanced LIGO vs. Initial LIGO
Advanced LIGO vs. Initial LIGO
6
Seismic Isolation System
Seismic Isolation System
Test mass motion should be < 10‐19 [m/rtHz] at 10 Hz
Ground Motion at 10 Hz ~ 10
Ground Motion at 10 Hz 10‐9 [m/rtHz]
10 orders of magnitude of isolation needed for test masses!
7
Seismic Isolation System
Seismic Isolation System
Test mass motion should be < 10‐19 [m/rtHz] at 10 Hz
Ground
Motion at 10 Hz ~ 10
10‐9 [m/rtHz]
Ground Motion at 10 Hz 10 orders of magnitude of isolation needed for test masses!
1
8
Seismic Isolation System
Seismic Isolation System
Test mass motion should be < 10‐19 [m/rtHz] at 10 Hz
Ground Motion at 10 Hz ~ 10
Ground Motion at 10 Hz 10‐9 [m/rtHz]
10 orders of magnitude of isolation needed for test masses!
2
3
1
9
Seismic Isolation System
Seismic Isolation System
Test mass motion should be < 10‐19 [m/rtHz] at 10 Hz
Ground Motion at 10 Hz ~ 10
Ground Motion at 10 Hz 10‐9 [m/rtHz]
10 orders of magnitude of isolation needed for test masses!
2
3
4
5
1
6
7
10
Advanced LIGO vs. Initial LIGO
Advanced LIGO vs. Initial LIGO
11
Brownian motion
Brownian motion
Dissipation causes fluctuations‐ high quality factor suspensions reduce thermal noise. i
d
h
l i
12
Advanced LIGO vs. Initial LIGO
Advanced LIGO vs. Initial LIGO
13
Quantum Noise
Quantum Noise
• High power laser 120 Watts input power
Watts input power planned, ~1kW in arm
• 40 kg test masses
k
• Signal Recycling (RSE)
• Squeezing?
14
Harry, G. M., et al. CQG 27.8 (2010): 084006.
• Advanced LIGO changes from initial LIGO
Advanced LIGO changes from initial LIGO
• Where are we now?
– Installation
I t ll ti
– Lock acquisition
• Path to detection
15
2011
Timeline
2012
Livingston
g
installation
Hanford
Jan 2011
2014
2013
full lock
full lock
installation
October 2012
Jan 2013
April 2014
January 2015
A
t
August 2014
16
Installation status:
Installation status:
Major installation at Livingston completed last month!
Temporary optics to be replaced this summer at Hanford tH f d
Signal Recycling cavity installation wrapping up this week at Hanford
P Fritschel E Gustafson
17
Integration Testing
Integration Testing
Input Mode Cl
Cleaner locking
l ki
2011
2012
2013
Livingston
2014
f ll l k
full lock
full lock
Hanford
Arm locking
Vertex Locking
Vertex first at Livingston, arms first at Hanford speeds up commissioning by allowing for copy and paste style commissioning
by allowing for copy and paste style commissioning
18
Lock Acquisition Scheme:
Acquisition Scheme:
•Problem: Weak actuators, small linear range, 5 coupled length degrees of freedom
•New approach: Independent locking of vertex and arms
Lock Acquisition Scheme:
Acquisition Scheme:
•Arm length stabilization controls resonance g
condition of main laser in the arms
•Can hold arm off resonance while vertex is being locked, then bring arms into resonance in controlled way
Arm Length Stabilization Noise Budget
A L th St bili ti N i B d t
Preliminary
Courtesy Alexa Staley
21
Vertex locking:
Vertex locking:
• Lock with standard demodulation technique
Lock with standard demodulation technique
• Third harmonic demodulation
– Less sensitive to carrier field
L
iti t
i fi ld
– Less sensitive to arms
22
Sign
nal Recyclin
ng Cavity Leength m/rtt Hz
Signal Recycling Cavity Noise Budget
Signal Recycling Cavity Noise Budget
Preliminary
23
Similar budgets for Michelson and Power recycling Courtesy Denis Matrynov, Anamaria Effler
Current Integration Progress
Current Integration Progress
• Both sites locking 2 arms +vertex
Both sites locking 2 arms +vertex
(no signal recycling cavity at Hanford)
• Attempting to transition arm common mode to i
ii
d
reflected IR sensor
• Full locking at Livingston any day
• First look at aLIGO noise 24
Initial LIGO Sensitivity improvement
Initial LIGO Sensitivity improvement
First lock at the end of 2000…
2002
2003
2004
2005
2007
25
Approximate commissioning plan
Approximate commissioning plan
Class. Quant. Grav.
27 173001 (2010)
27, 173001 (2010)
26
Criteria for early observing runs
Criteria for early observing runs
3rd run: >6 months @ > 150 Mpc
2nd run: >3 months @ 100 Mpc, “likely” detection (2016‐2017)
1st run: 2 months @ 50 Mpc, we could be lucky! (late 2015)
27
Courtsey L. Barsotti
Some possible bumps in the road…
Some possible bumps in the road
28
The path to detection
The path to detection
Might look like this…
Or more like this
Or more like this…
29
30
The image part with relationship ID rId61 was not found in the file.
LIGO Scientific Collaboration
31
Seismic platform performance
Seismic platform performance
All 20 isolation platforms installed at two sites
Third harmonic locking scheme
Third harmonic locking scheme
•Standard 1f modulation/demodulation signals sensitive to phase of carrier and sidebands
•Carrier phase shifts due to arm cavity resonances di t b th i l
disturb the signals used to lock vertex degrees of dt l k
t d
f
freedom
Ω
•Demodulating with the third harmonic produces signals that are less sensitive to the carrier
3Ω
33
LIGO India
LIGO‐India
34
Signal recycling cavity
Signal recycling cavity
35