Current status of Joint LIGOTAMA Inspiral Analysis

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Current status of Joint LIGO-TAMA Inspiral
Analysis
Hirotaka Takahashi / Stephen
Fairhurst (Osaka Univ. and Niigata Univ.
/ Univ. of Wisconsin-Milwaukee)
In collaboration with Patrick Brady, Nobuyuki
Kanda, Hideyuki Tagoshi, Daisuke Tatsumi, the
LIGO Scientific Collaboration and the TAMA
Collaboration
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Introduction

• LIGO and TAMA300 performed a coincident
  observation
• between Feb. 14 and April 14, 2003.

• The total amount of LIGO S2 science-mode data
  (one or more detectors)
• is 1218 hours.

• The total amount of TAMA300 DT8 observation data
  is 1163 hours.

• We report on the current status of the
  coincidence analysis to search
• for gravitational waves from inspiraling
  compact binaries using LIGO (S2)
• and TAMA300 (DT8) data.

TAMA300 (T1)
LIGO Hanford (H1 and H2)
LIGO Livingston (L1)
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Goals of the LIGO-TAMA search

• The ultimate goal of the search is a detection.

• Sensitive to most of the Milky Way.

• We can place an upper limit on compact star
  inspiral rate in
• the Milky Way (if no detection).

LIGO S2-TAMA DT8 coincidence data in 2003
TAMA
LIGO single site
nL1 L1 was not operating

• T1 1163 hours
• (L1-nH1-nH2)(nL1-H1-nH2)(nL1-nH1-H2)(nL1-H1-H2
  ) 785 hours
• (L1-nH1-nH2-T1)(nL1-H1-nH2-T1)(nL1-nH1-H2-T1)(
  nL1-H1-H2-T1) 650 hours

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In this talk
We focus on what has been learned from playground
data.

• To avoid statistical bias,
• Tuning of analysis parameters are decided.
• Test analysis is performed.

Playground data 64 hours
(not included upper limit calculation)

• 1. We determined our choice of coincidence
  parameters
• using the results of Galactic binary neutron
  star inspiral
• signals injection.
• 2. We performed time slide analysis to estimate
  the background.
• 3. We injected Galactic binary neutron star
  inspiral signals
• into both LIGO and TAMA data to evaluate
  efficiency.

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Tuning coincidence parameters

• Time windows

• The distance between LIGO and TAMA

• Maximum time delay of the signal

• Timing accuracy ?

• Since we are planning to test for coincidence
  between LIGO
• and TAMA triggers using the time, we decided
  to check
• how accurately LIGO and TAMA can determine
  this quantity.
• To do this, injected a set of Galactic binary
  neutron star signals
• into the LIGO-TAMA playground times.

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Accuracy of coalescence time
The triggers of LIGO and TAMA are recorded within
1.5 msec of the injection
Time windows
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Tuning coincidence parameters

• Mass windows
• Chirp mass window? Reduced mass window?

• The accuracy of chirp mass

LIGO (455 injections)
TAMA (660 injections)
The accuracy of chirp mass
Detected-Injected chirp mass (Msol)
Detected-Injected chirp mass (Msol)