Virgo Logbook

Detector Characterisation (General)

cohen, arnaud - 18:49 Tuesday 10 April 2018 (41052)

Lock losses tracker and categoriser webpage (and tool)

A webpage displaying the last 300 lock losses(*) is available at https://scientists.virgo-gw.eu/lock-losses/. For each lock loss, the webpage also shows the ITF_lock index before the lock loss, the ITF mode, the Metatron nodes involved in the lock loss, some potential causes (called issues on the webpage) of the lock loss, the earliest of these recorded issues, a link to a set of plots, and a link to the merged time-sorted Metatron logfiles.

Further information: the potential causes are obtained thanks to some custom functions that test behaviours of various channels (around 10-15 up to date). Hence, they are labelled as "potential" as one is only running a limited set of checks; the "earliest issue" is the one with the lowest GPS time associated. These are meant to help for a deeper investigation of a given lock loss.

This is a first version of this framework; comments and feedback will be more than welcome to help improve the package and make it more useful for commissioning.

(*) Defined as a Metatron node making a transition from a higher state to down or init.

Comments to this report:

verkindt - 13:04 Thursday 12 April 2018 (41082)

Currently, there is in VIM some information about lock segments, updated periodically: https://vim.virgo-gw.eu/?config=39 If your interesting lock losses page is updated regularly, we could add a link to it in this VIM page.

cohen - 19:11 Friday 13 April 2018 (41107)

The webpage is actually updated with a period shorter than 20s. Now, according to the time that the script looking for lock losses would spend, the latency so that the last lock losses information is displayed, can increase up to few minutes (for now).
The link to the lock segments VIM page has been added.

cohen - 17:03 Thursday 19 April 2018 (41153)

Erratum!
The lock losses are not "Defined as a Metatron node making a transition from a higher state to down or init" but rather as a Metatron node transitioning from a nominal state of ITF_LOCK (META_ITF_LOCK_index) to DOWN or INIT. Indeed, they are basically defined according to flag channels DQ_META_LOCK_LOSS_{DoF}, which are themselves defined as explained.