ASI glitches for BNS vetoes

Chad Hanna

Louisiana State University

channa@phys.lsu.edu

Presented for the LSC

Detector Characterization Session

LIGO Livingston Observatory

Wednesday March 23, 2005

LIGO-G050169-00-Z

Gabriela Gonzalez

Louisiana State University

gonzalez@lsu.edu

Lindy Blackburn

MIT

lindy@ligo.mit.edu

Outline

Motivation

Initial look at S3 playground events.

Safety

S3 Playground final results

S4 and beyond...

Motivation

The possibility of an ASI veto came about while investigating a loud L1 BNS trigger.

Comparison to injections suggested it could be made safe.

Initial Look at S3 data

We had a look at the 10 loudest BNS playground triggers for each IFO and generated ASI/ASQ plots.

We found significant ASI correlation in many triggers.

We looked at coincident ASI KW triggers to see if we might be able to construct a useful veto

Parameters

1. KW energy threshold (1.5)

2. KW ASQ/ASI ratio (2.0)

3. Veto window (-1, +8)

The Dreaded Question of Safety

Is it safe to use the ASI channel for vetoes?

NO. ASQ and ASI are known to be coupled.

But we can choose a safe ratio from injections.	(S3 injections had bad endings which may have produced excess ASI signal)

Results from Hardware Injections

Distribution of KW ASQ/ASI ratio for injections

S3 Playground Final Results

We only considered H1 for the ASI veto because:	1. We didn't have adequate hardware	injections for L1.	2. H2 had a successful PRC_CTRL veto (work by Nelson Christensen)

We vetoed 1/3 of the BNS triggers above 60 SNR (actual efficiency might be better)

Used 90% of the KW triggers available for veto.

Had an extremely small deadtime - .33%

S4 and Beyond

Although I haven't begun the S4 analysis, everything is in place to

do so. However daily summary plots made by Alex Dietz seem

to suggest that an ASI veto will be useful.

And Safe???

2005-03-20T12:37:14