1. VOEvent IVOA Interop May 2006 Roy Williams NVO.Caltech..... and many others..... 1604 image of Cas A

2. Multiple Event Streams Swift (Barthelmy) HETE2 (Butler) Integral (Djorgovski will consult) Raptor (Vestrand/White) SDSS supernova search (Becker/Masao) KAIT (Fillipenko/Li) Microlensing Planet Search (Gaudi) Essence (Smith, Wood-Vesey) Palomar-Quest (Djorgovski) Pairitel (Bloom) Panstars (Kaiser, Price) AAVSO (Price) XTE satellite (Remillard) Glast (E. Bloom) Allen Telescope Array (Bower) KAIT (Fillipenko/Li) Pairitel (Bloom) Palomar P60 (Kulkarni) Robonet (Steele) AAVSO (Price) Raptor (Vestrand/White) Gemini (8 meter telescopes) ROTSE (Akerlof) Prompt (Reichart) CTIO Smarts (Cobb, Baylan) Event Authors Robotic Telescopes

3. VOEvent Structure  Who  Publisher, Contact, etc  Subscribers will use AuthorIVORN to select  WhereWhen (== STC)  Can be simple eg RA, Dec, eg UTC  Can be sophisticated, eg multiple frames, near objects, etc  What  Hierarchy of named parameters  Units, Semantic type (UCD)  References, Descriptions  How  How was the evidence gathered: camera, telescope, etc  Why  probability list of interpretation supernova, comet, asteroid,.....  Citation  Link to other VOEvent: Followup, Supercede, Retraction,  Link to support data  Reference  Supporting material, eg lightcurve, image

4. is the scientifically-responsible Author? Rapid Telescope for Optical Response Raptor http://www.raptor.lanl.gov/images/RAPTOR_patchLarge.jpg Robert White rwhite@lanl.gov +1 800 555 1212 ivo://raptor.lanl/organization or An IVORN for an organization Easier for Subscribers to find Author Shorter packet

5. was actually observed Parser can cast this Group to class phot_pt A time sequence of R- magnitudes

6. do we think this happened? Tycho's Stella Nova SN Ia 3C 10 supernova remnant Importance of the event observation should I interrupt my telescope schedule? Publisher thinks (prob=0.98) this is a SN1a with given name Possibility this is associated with object 3C10

7. Space-Time Coordinates 2005-04-15T23:59:59 1.0 148.88821 69.06529 0.03 </AstroCoords Standard STC coordinate frame

8. Caltech Exeter LANL NOAO SDSS SNe U Washington/Stanford Pairitel Berkeley Palomar P60 Caltech Palomar-Quest Caltech Raptor LANL Liverpool Telescope La Palma UKIRT Hawaii Author Publisher Repository Relay Subscriber Faulkes Hawaii/Australia OGLE III Poland GCN NASA/GSFC Microlensing Survey Exeter CTIO/KPNO surveys VOEventNet and eStar

9. VOEvent transport model Publisher Subscriber Author immediate push digest (RSS) resolve query Multiple authors, publishers, subscribers Structured, semantically rich, for machine understanding XML representation Standard transports (web service, email, etc) Standard global identifiers Repository client Aggegator Filter

10. VO Identifiers Registry finds the VOEvent repository Repository finds the specific event ivo://pq.nvo.caltech/VOEPublisher # 20050523c Publisher IVORN Resolved by registry to find repositories Local ID Not known to registry Created by Publisher Known to event repository delimiter Event IVORN (whole thing)

11. Author (science) Publisher (identifier, signature) Repository Registry Usage for VOEvent Client 1.Resolve identifier ivo://publisherID#localID 2. Which repositories have events from this publisher? 3: Send localID 4: Receive event metadata publish event store event VO Global Registry Subscribers

12. Citation  An event can cite another ivo://gcn.nasa/VOEvent#hete_389241a_20050808_230931  Observations can be federated by mutual citation followup observation event collection

13. Control  Author A sends event E to Subscriber S Subscriber software decides on action....  S can followup everything from A  S can followup if importance > threshold  (importance is part of every event)  S can followup if prob(Supernova) > threshhold  section has hypothesis, concept, association  S can examine the parameters, images, lightcurves  section is observations

14. Transport  Querying and web pages as usual client connects to server RSS polling is like this  Subscription One of  Client keeps open socket to server  Server keeps open connection to client (GCN model)  Subscriber protocol Jabber/XMPP -- popular IM protocol Home made -- “TCP Vanilla” Java Messaging One-way SOAP (port 80)

15. Event Synthesis Engine Pairitel Palomar 60” Raptor PQ next-day pipelines catalog Palomar-Quest known Variables known asteroids SDSS 2MASS PQ Event Factory remote archives baseline sky eStar VOEventNet VOEventNet: a Rapid-Response Telescope Grid VOEvent database

16. VOEvent Structure  Event has ivo:// identifier (the IVORN)  Citation  Keep it light -- no data in VOEvent-- use links  Citation connects events  Discovery, Followup, Supercede, Join, Predict  Subscription / query / digest (RSS)  get only the events you want based on complex criteria based on publisher  crossmatch event libraries  Transport fabric  for human: email, cellphone, IM  for robot: IM, web-service, auto-email, socket

17. VOEvent Schema 1.1 Last major schema change? End of the Beginning of VOEvent.....

18. Ivorn for IVOA identifiers ivorn  International Virtual Observatory Resource Name  Can be recognized by ivo:// at start in place of id  (collides with XML usage of this attribute)

19. MIME type  VOEvents should be application/xml+voevent

20. Roles  Author  Scientific Responsibility  Metadata same as IVOA Organization  title, shortName, description, logo, contact (Name, Email, Phone), Contributor  Publisher  XML Responsibility  Creates unique IVORN  Subscription interface  Repository  Resolves IVORNs  Query interface (SEAP)  Relays, Filters, and Brokers  Combinations of basic roles

21. now means Author  The element how has AuthorIVORN in place of PublisherID  Choice of explicit or implicit metadata

22. VOEvent and Registry  Author may be registered may be cited by IVORN in VOEvent packet  Saves typing  Easier for subscriber to pick known authors  equivalence of with IVOA Organization  Publisher is registered  List of authors, How to subscribe  Repository is registered  Which publishers are kept  IVORN resolution. Query interface

23. Queries for VO Registry  Tell me about this Author  Tell me about this Publisher  Tell me about this Repository  Which Publisher has this Author?  Which Repository has this Publisher?

24. VOEvent identifier (IVORN) 1. Given an event ivorn: ivo://nvo.caltech/voe-publisher#666 2. parse into: publisher ivorn: ivo://nvo.caltech/voe-publisher and local key: 666 3. Ask VO registry: Which repository has this publisher? 4. Use query interface on repository: Tell me about event 666

25. STC adopted (No more mealy-mouthed nonsense about RA and Dec elements) pseudocode Let x = WhereWhen/ObsDataLocation/ ObservationLocation/AstroCoords If x[@coord_system_id=‘FK5-UTC-TOPO’] then Let Time = x/Time/TimeInstant/ISOTime Let RA = x/Position2D/Value2/C1 Let Dec = x/Position2D/Value2/C2 < ObsDataLocation xmlns="http://www.ivoa.net/xml/STC/stc-v1.30.xsd" xmlns:xlink="http://www.w3.org/1999/xlink"> <ObservatoryLocation id=”KPNO" xlink:type="simple" xlink:href="ivo://STClib/Observatories#KPNO"/> 2005-04-15T23:59:59 1.0 148.88821 69.06529 0.03

26. Concept  The element now holds controlled vocabulary  For draft (IVOA Semantics WG), see  http://www.ivoa.net/twiki/bin/view/IVOA/VOEventVocabulary