VOEventIVOA InteropMay 2006

Roy WilliamsNVO.Caltech

..... and many others .....

1604 image of Cas A

Multiple Event StreamsSwift (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

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

<Who>is the scientifically-responsible Author?

<Author> <title>Rapid Telescope for Optical Response</title> <shortName>Raptor</shortName> <logoURL>http://www.raptor.lanl.gov/images/RAPTOR_patchLarge.jpg</logoURL> <contactName>Robert White</contactName> <contactEmail>rwhite@lanl.gov</contactEmail>

<contactPhone>+1 800 555 1212</contactPhone></Author>

<AuthorIVORN>ivo://raptor.lanl/organization</AuthorIVORN>

or

• An IVORN for an organization• Easier for Subscribers to find Author• Shorter packet

<What>was actually observed

<What>

<Group type="phot_pt" > <Param name="mag1" ucd="phot.mag;em.opt.R" value="13.2" unit="mag" /> <Param name="epoch1" ucd="time.epoch" value="245523.12345" unit="day"/> </Group>

<Group name=”gamma_flux"> <Param name="counts" value="73288" ucd="phot.count"/> <Param name="peak" value="1310" ucd="arith.rate;phot.count"/> </Group>

</What>

Parser can cast this Group to class phot_pt A time sequence of R-

magnitudes

<Why>do we think this happened?

<Why importance="13.0" expires="1574-05-11T12:00:00"><Inference probability=”0.98">

<Name>Tycho's Stella Nova</Name> <Concept>SN Ia</Concept> </Inference> <Inference probability=”0.2" relation="associated” >

<Name>3C 10</Name> <Concept>supernova remnant</Concept> </Inference> </Why>

Importance of the event observationshould I interrupt my telescope schedule?

Publisher thinks (prob=0.98) this is a SN1a with given name

Possibility this is associated with object 3C10

<WhereWhen>Space-Time Coordinates

<WhereWhen> <ObsDataLocation xmlns="http://www.ivoa.net/xml/STC/stc-v1.30.xsd" > <ObservatoryLocation id="KPNO" xlink:type="simple" xlink:href="ivo://STClib/Observatories#KPNO"/>

<ObservationLocation> <AstroCoordSystem id="UTC-FK5-GEO" xlink:type="simple" xlink:href="ivo://STClib/CoordSys#UTC-FK5-GEO/> <AstroCoords coord_system_id="UTC-FK5-GEO"> <Time unit="s"> <TimeInstant> <ISOTime>2005-04-15T23:59:59</ISOTime> </TimeInstant> <Error>1.0</Error> </Time> <Position2D unit="deg"> <Value2> <C1>148.88821</C1> <C2>69.06529</C2> </Value2> <Error2Radius>0.03</Error2Radius> </Position2D> </AstroCoords </ObservationLocation> </ObsDataLocation></WhereWhen>

Standard STC coordinate frame

Caltech

Exeter

LANL

NOAO

SDSS SNe U Washington/Stanford

PairitelBerkeley

Palomar P60Caltech

Palomar-Quest Caltech

RaptorLANL

Liverpool TelescopeLa Palma

UKIRTHawaii

AuthorPublisherRepositoryRelaySubscriber

FaulkesHawaii/Australia

OGLE IIIPoland

GCNNASA/GSFC

Microlensing Survey Exeter

CTIO/KPNO surveys

VOEventNet and eStar

VOEvent transport model

Publisher

Subscriber

Author

immediatepush • digest (RSS)

• resolve• query

Multiple authors, publishers, subscribersStructured, semantically rich, for machine understandingXML representationStandard transports (web service, email, etc)Standard global identifiers

Repository

client

Aggegator Filter

VO IdentifiersRegistry finds the VOEvent repositoryRepository 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 delimiter

Event IVORN (whole thing)

Author(science)

Publisher(identifier, signature)

Repository

Registry Usage for VOEvent

Client

1. Resolve identifierivo://publisherID#localID

2. Which repositorieshave events from this publisher?

3: Send localID

4: Receive eventmetadata

publishevent

storeevent

VO GlobalRegistry

Subscribers

Citation An event can cite another

<Citations><EventID cite=”followup"> ivo://gcn.nasa/VOEvent#hete_389241a_20050808_230931

</EventID> </Citations>

Observations can be federated by mutual citation

followupfollowup

followup

observation

event collection

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

<Why> section has hypothesis, concept, association S can examine the parameters, images, lightcurves

<What> section is observations

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)

Event Synthesis Engine

Pairitel

Palomar 60”

Raptor

PQ next-daypipelines

catalog

Palomar-Quest

knownVariables

knownasteroids

SDSS2MASS

PQ Event Factory

remote archives

baselinesky

eStar

VOEventNet

VOEventNet: a Rapid-Response Telescope Grid

VOEventdatabase

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

VOEvent Schema 1.1

Last major schema change? End of the Beginning of VOEvent.....

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)

MIME type VOEvents should be

application/xml+voevent

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

<Who> now means Author The <Who> element how has

AuthorIVORN in place of PublisherID Choice of explicit or implicit metadata

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 <Who> with IVOA Organization

Publisher is registered List of authors, How to subscribe

Repository is registered Which publishers are kept IVORN resolution. Query interface

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?

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

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

<WhereWhen>

<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"/>

<ObservationLocation> <AstroCoordSystem id="FK5-UTC-TOPO"/>

<AstroCoords coord_system_id="FK5-UTC-TOPO">

<Time unit="s">

<TimeInstant> <ISOTime>2005-04-15T23:59:59</ISOTime> </TimeInstant> <Error>1.0</Error> </Time>

<Position2D unit="deg">

<Value2>

<C1>148.88821</C1>

<C2>69.06529</C2> </Value2> <Error2Radius>0.03</Error2Radius> </Position2D> </AstroCoords> </ObservationLocation> </ObsDataLocation> </WhereWhen>

Concept The <Concept> element now holds

controlled vocabulary

For draft (IVOA Semantics WG), see http://www.ivoa.net/twiki/bin/view/IVOA/VOEventVocabulary