Report on the Observation Runof TAMA300 in the Spring of 2003
National Astronomical Observatory of Japan
Koji Arai (TAMA project)

ICRC2003

TAMA300l Laser interferometric GW detector
with arm length of 300m
Site: National Astronomical Observatory of Japan,(Mitaka, Tokyo)l Objects of the project
To develop a detector capable
to detect GW eventsin nearby galaxies.

WestEndRoomSouthEnd
RoomTo establish techniques
for a future km-class interferometer
Designed sensitivity ~hRMS = 3 x 10-21 @300Hz (BW300Hz)

CenterRoomHistory of TAMA development
1995
1996

Recombine I
98/5 - 99/1

1997

Mode Cleaner
97/4 - 97/12300m
FP cavity

10W Laser

Mode Cleaner+ 10W Laser
98/1 - 99/1300m
FP cavity

Project started
Facility construction
completed
Vacuum systemcompleted

1999/8
Data Taking 111h
1999/9
Data Taking 231h
2000/4
Data Taking 313h
2000/8,9 Data Taking 4 167h
2001/3
Data Taking 5 111h
2001/8,9 Data Taking 6 1038h
2001/10- Recycling experiment

Recycling I
01/10 - Present

One Arm
2002/8-9 Data Taking 7
97/8 - 98/425h
2003/2-4 Data Taking 8 1158h

10mMode Cleaner

Recombine II
Recombine III

99/2 - 00/600/9 - 01/9

Data taking (DT) runs in past
6 observations without power recycling
2 observations with power recycling[Without power recycling]DT1 1999 Aug. 6~ 7

1 night

11 hours

DT2 1999 Sep. 17~20

3 nights

31 hours

DT3 2000 Apr. 20~23

3 nights

13 hours

DT4 2000 Aug. 21~Sep. 4 13 nights 167 hours
DT5 2001 Mar.

2~ 8

6 days111 hours Coincidence

DT6 2001 Aug. 1~Sep. 20 50 days 1038 hours

LISM(20m)[With power recycling]DT7 2002 Aug, 31~Sep. 2

1 day

25 hours

DT8 2003 Feb. 14~Apr. 15 59 days 1158 hours

LIGO & GEO
LIGOData Taking 8l DT8 ~ 2 months run (2003/2/14~4/15)- First full-time joint observation with LIGO
(called S2 in LIGO)- First long-term observation with power recycling
Power recycling of TAMA300 (2001/10~Present)
PowerRecycling
mirror300m arm

300m arm

Laser

Key points on the long-term obs.
l The detector must operate:~ as sensitive as possible => Dr. Sato's talk
Improved sensitivity by power recycling
Power recycling gain of 4.5
Best sensitivity: 2.7x10-21[/Hz1/2] (@1.5kHz)~ as long as possible
Improved stability from the previous run
Accumulated data: 1158 hours(segment longer than 10min)
Duty cycle:
81.3%
Longest lock:20.5 hours~ as easy as possible
Automatic lock acquisition system using a master controller
and digitally-switched analog circuits

Maintaining the stabilityl Seismic activity
The TAMA site is in the middle of a city arearoughtly 10 times worse than those of the other large IFOs
100~1000 times worse than in Kamioka-mine=> Test mass alignment control / Active vibration isolatorl Drift compensation
Optical path length / mirror alignment driftTemperature drift
Ground deformation by ground water pumping=> Length drift compensation
Recycling mirror alignment
Optical axis control

Improved long-term stability
Longest lock stretch in the observations

Transmitted power [a.u.]54

DT8: 20h31m

32

DT7: 8h38m

100

5

10
Time [hour]1520

Duty cyclel 1157h51m (out of 1424 hours, duty cycle 81.3%)
Start: Feb 14, 2003, Fri, 23:00:00 JST, End: Apr 15, 2003, Tue, 07:00:00 JST (Total run time: 1424:00:01)
Total long obs. time: 1157:51:26, Duty cycle: 81.3102%7S S

Avg duty cycle (81.3%)
CC C

Obs. time in each shift [hours]

6C CW

DAQTrouble
5C C CC
WWWCircuit
Failure

1200

S1000

C C CC

CC CW

Laser
TroubleC C

CCWCC C C CC C C C
RoadWW W
High Constructions
800
Sea
Waves
MCTrouble

4600

PowerFailure

3400

2200
10 141516171819202122232425262728010203040506070809101112131415161718192021222324252627282930310102030405060708091011121314150Feb

Mar

Apr

Total Obs. time [hours]

8Signal Injection
ExperimentDT8 ~ Disturbance by construction

Observable
Distance [kpc]Seismic level[mgal (=10-5m/s2)]

13rd May, 2003 (Thu)(Noisy weekday)
30
2520
15
1050Construction works
near the site

Seismic level vs Duty cycle
Duty cycle vs Seismic motion

1Duty Cycle

0.8
0.6
0.4
0.2
005101520
Seismic Motion (mgal)

25

Duty cycle

Daily trend of duty cycle/sensitivity
1.0
0.8
0.6
0.4
0.2
0.0
0

Lunch
time

3

6

91215
Hour (JST)182124

Observabledistance [kpc]With construction ~ IFO didn't work => Duty cycle about 60%
40302010003

691215Hour (JST)182124

Even without construction ~ sensitivity reduction of about 20%Summaryl Gravitational wave detector TAMA300
A Michelson interferometer with 300-m cavity arms
located at Mitaka in Tokyo, Japan.

l Data Taking 8
Full-time joint observation with LIGOFirst long-term operation with power recycling
With improved sensitivity by power recyclingh = 2.7 x 10-21 /sqrtHz @1.5kHz
1158 hours of 1424 hours => duty cycle 81.3%
Main cause of the dead time: construction works neabyFuture Planl Data Analysis of the DT8 data
In progress. Preliminary result for NS inspiral searchl Investigation on the noise issuesl Further automation of the observation
To operate the interferometerwith less operatorsl Upgrade of the vibration isolation
Seismic attenuation system (SAS)Isolation from low frequency (~0.1Hz)
R&D by Caltech, U-Tokyo and U of Pisa
Installation in early 2005l More power in the arms
High gain (G=10) recycling

SAS (Univ. of Tokyo)