The State of VOEvent Rob Seaman, NOAO/DPP IVOA InterOp, Trieste 22 May 2008

Todays agenda: V2.0, time series, orbits, and all that – Rob Seaman Portfolios for Event sharing & evaluation – Matthew Graham VO-GCN (Let the revolution begin!) – Scott Barthelmy Resisting the forces of (unnecessary) change – Alasdair Allen

Key issues are: Embracing: Vocabularies semantically aware science Signatures data integrity / per stream DQA External schemata outside communities Time series the larger time domain Orbital elements the workflow Registry the VO vision Tweaks the real world

Vocabularies – & As at Mondays excellent session (& next) Seems well in hand No modification of standard needed can support controlled vocab. can contain anything When new vocabulary is ready, just use explicitly

Signatures – envelope As at Wednesdays excellent session Dont include signature in Pick one or the other technology, or both and let the market decide Encourage (not require) wide usage Encourage (demand?) broker support

External schemata – Already in use Heliophysics Knowledgebase Must be compatible with IVOA usage Schema must support this Registry must handle this A small change may be needed to the language of the standard

Time series vs. orbital elements Seem similar, but very different VOEvent is a report of observation(s) of transient phenomena,with the implication that timely follow-up is being requested A time series expresses the previous sky was the behavior (thus not STC) An orbit predicts future sky behavior to look next time (STC)

Time series – Spectral Data Model vs. Napkin representation WG discussed several variations after Hotwired workshop Make as simple as possible to start Can elaborate in later revisions

Napkin representation What we signed at Hotwired in Tucson, June 2007

Time series example (per Roy & Al)

Time series metadata

Time series metadata, #2

Time series metadata, #3

Time series questions Chain of packets or embedded in single packet? or extend the schema? or both? VOEvent specific or general VO DM? or both? If so, SDM or STC?

A time series is an aggregate object multiple instruments joint curation complex footprint in time and in space for moving objects requires matched calibrations object(s), not detections must build associations

Orbital elements – A targeting ephemeris If STC can gracefully handle this, it will go a long way to resolving STC status in VO

Orbit example T00:00:00

Orbit example, # T00:00: T00:00:00

Orbit example, #3 <CatalogEntryLocation xmlns=" xmlns:xlink=" xmlns:xsi=" xsi:schemaLocation=" <AstroCoordSystem xsi:nil="true" xlink:type="simple" xlink:href="ivo://STClib/CoordSys#TDB-ECLIPTIC-BARY" id="TDB-ECLIPTIC-BARY"/> T00:00: T00:00:00

Alternate orbit representations STC provides options: orbital elements Pole and pericenter vectors RA, Decs at intervals

Pole and vector notation: T00:00:00 P T00:00:00 Q

Discrete pointings T00:00: T00:00: T00:00:

Minor tweaks? Permit Any others?

Registering VOEvent assets As discussed Wednesday (Thanks Roy!) VOEventStream Scientifically coherent entity VOEventService or VOEventServer? Logistically clustered functionality Provides simple schema for

Work products 1)v2.0 standard document v2.0 schema 2)VOEvent vocabulary (or -ies) 3)VOEvent registry document Registry schema 4)Pilot signing technologies 5)Transport document 6)User guide

Future events Finalize v2.0 by the Fall InterOp HTN coordination (HTN IV) ADASS tutorial (or BoF?) VOEvent IV (Spring 2009?) IAU GA 2009? Time domain astronomy SPIE 2010? Many other activities continue apace

Agenda: V2.0, time series, orbits, and all that – Rob Seaman Portfolios for Event sharing & evaluation – Matthew Graham VO-GCN (Let the revolution begin!) – Scott Barthelmy Resisting the forces of (unnecessary) change – Alasdair Allen