H1 SEI

jim.warner@LIGO.ORG - posted 11:45, Thursday 19 May 2016 - last comment - 15:09, Thursday 19 May 2016(27299)

A brief intro to end-station ISI states.

Last week, TJ created some guardian node to manage the configuration of the endstation ISI's, alog 27141. The intention is for these to be the primary interface for commissioners and operators in changing the Seismic configuration, depending on environment. I'm providing some guidance on when the different states should be used here.

THIS NOT EVEN A GUIDE, JUST SUGGESTIONS.

The guardian code is still being worked on, configurations still need to be tested. Thats why there are fields with options, or without a full description of the state. The wind speeds are pretty much guesses, but the 10% and 90% microseism are indicated on with dashed lines on the .1 - .3 hz BLRMS on the seismic foms.

Wind speed	0-10 mph	10-25 mph	25-35+ mph
Microseism	0-10 mph	10-25 mph	25-35+ mph
10%	Quite_90 No SC	Quite_90 No SC	Some windy configuration
10-90%	Quite_90 No SC, or Quite 90 useism depending on microseism	Quite90 useism Quite_90 BRS	Quite_90 BRS Some windy config
90% +	45 No SC, 45 Useism 45 BRS SC depending on microseism	Quite 90 BRS	There be dragons here.

Comments related to this report

jeffrey.kissel@LIGO.ORG - 15:09, Thursday 19 May 2016 (27305)

Link

For your viewing pleasure, I translate between the states indicated by Jim in his table above and the actual name of the states in the Guardian Configuration nodes created by TJ (as Jim cites, see LHO aLOG 27141), and other Jargon that we'cve been tossing around in the SEI group:


State Name                 Jim's Table Name       Sensor Correction Description
BLEND_Quite_90_SC_BRS      Quite_90 BRS           BRS-corrected STS GNDX to ST1X (or GNDY to ST1Y), "broad"-band filter (0.08 - 0.5 Hz)
BLEND_Quite_90_SC_useim    Quite 90 useism        STS Alone, using "narrow"-band focused at the microseism (0.1-0.3 Hz)
BLEND_Quite_90_SC_None     Quite_90 No SC
BLEND_45mHz_SC_BRS         45 BRS SC
BLEND_45mHz_SC_useim       45 Useism              Runs in the corner station (but there's no node)
BLEND_45mHz_SC_None        45 No SC               Before BRSs existed, this was the nominal configuration for the End Stations
     

Note that I put "narrow" and "broad" band in quotes, because there's about 10 sensor correction filter options and none of them are really truly narrow or broad in their modelled / expected performance, and any real performance depends heavily on the ground motion. E.g. while one might expect to get great performance out of a broad-band sensor correction filter, if it's windy, that ideal performance may be completely washed out by other noise.

Images attached to this comment