From gmendell@ligo-wa.caltech.edu Fri Jan 26 00:06:08 2007
Date: Thu, 25 Jan 2007 21:07:40 -0800
From: Gregory Mendell 
To: Keith Riles 
Subject: Re: [ligo-dc] Detchar telecon Friday at 1:30 p.m. EST; notes and links for fscan update

Hi Keith,

Below are notes and links for what I plan to present tomorrow:

FSCAN: frequency spectrogam and spectra generated from SFTs. The code
and driver scripts are available from lalapps/src/pulsar/MakeSFTs and
lalapps/src/pulsar/fscan. (Xavier Siemens and Rejean Dupuis have also
contributed to some of this code.)

The purpose is to identify lines that could interfere with pulsar
searches, features that indicate problems with the IFOs, and/or features
that we might try to mitigate during commissioning work.

An example of new results showing a comparison of 18 days of
H0:PEM-BSC9_MAGX data and H1 h(t) data with a search for coincident
lines, is posted here (usual lsc access required):

http://ldas-jobs.ligo-wa.caltech.edu/~pulsar/fscan/S5/PEM/H1_Jan_20_07_BSC9_MAGX/fscanH1BSC9MAGX20Jan07.html

(It took about 1 hr running on 100 nodes to produce these results.  Ben
Johnson had previously prestaged the Level 1 RDS data from tape.)

There have been several improvements since the last report:

1. The code now organizes the output plots, and links to timestamps and
data files, into html.

2. The html can show a comparison with a set of "reference" plots from
another time and/or channel.

3. The code can do a coincidence search for lines with the reference data.

4. SFTs, and thus fscan, can now be generated from PEM channels.

More PEM results can be found by browsing the directories here,

http://ldas-jobs.ligo-wa.caltech.edu/~pulsar/fscan/S5/PEM/

and clicking on the .html files in each.  The next step it to run the
code on some of the special power supply ripple channels set up by
Robert Schofield during this week's commissioning period at LHO.  This
should yield more lines of interest than the magnetometer channels.

The fscan page with info on the previous results is here (not yet
updated with the latest results):

http://ldas-jobs.ligo-wa.caltech.edu/%7Epulsar/fscan/S5/hoftSFTspectra/H1L1CoincidenceAvePower/hoftFscanSpectrogramsAndSpectraOct2006.html

Cheers,
Greg