voeventnet caltech edu VOEvent Net By Matthew J
voeventnet. caltech. edu VOEvent. Net By Matthew J. Graham (Caltech)
What is VOEvent. Net? o o Real-time astronomy with a rapid-response telescope grid A peer-to-peer cyberinfrastructure to enable rapid and federated observations of the dynamic night sky A network of telescopes and computers working synergistically, under the watchful eye of humans, to find and study interesting astronomical events A transportation of events to interested subscribers, automatically in seconds or minutes after discovery 6 December 2005 VOEvent II
really What is VOEvent. Net? ^ o o $600 k 3 year NSF-funded project under the DDDAS (Dynamic Data. Driven Applications Systems) initiative involving Caltech, UC Berkeley and LANL Personnel: Roy Williams (PI) Joshua Bloom George Djorgovski Shri Kulkarni Thomas Vestrand 6 December 2005 Matthew Graham Ashish Mahabal Andrew Drake Derek Fox Przemek Wozniak VOEvent II
Architecture Palomar-Quest GRB satellites PQ next-day pipelines baseline sky Raptor catalog Palomar 60” PQ Event Factory Event Synthesis Engine VOEvent database VOEvent. Net Pairitel known variables known asteroids 6 December 2005 2 MASS SDSS remote archives VOEvent II e. Star
Palomar-Quest Survey o o o Synoptic sky survey using the 48” Palomar Samuel Oschin Schmidt telescope and the 112 -CCD, 161 -Megapixel Quest II camera Collaboration between Caltech, Yale/Indiana U. , NCSA, and JPL; et al. VO compliance/standards built in from the start Two modes: drift scan with UBRI/rizz or multiple repeated snapshots in one filter ~70 GB of data/night 15000 deg 2 observed a minimum of 8 times with baselines minutes to years 6 December 2005 VOEvent II
Real PQ data: The Big Picture o o o A 152 ft 20 ft mural produced for Griffith Observatory from PQ survey BRI images A swath of 15. 2 2. 0 swath through the center of the Virgo cluster, sampled at 0. 4 arcsec/pixel, giving a 136, 800 18, 000 pixel image Computed at CACR using Hyper. Atlas and a custom data cleaning pipeline Reproduced on 114 steel-backed porcellain plates, expected to last many decades Will be seen by millions of visitors Associated website will include NVO outreach 6 December 2005 VOEvent II
The Big Picture: detail 6 December 2005 VOEvent II
The Big Picture: more detail The Big Picture: Tile C 12 (M 87) Zoom-in 6 December 2005 VOEvent II
Transients in the Big Picture 740 Cantabia Tile b 07 6 December 2005 VOEvent II
Architecture Palomar-Quest GRB satellites PQ next-day pipelines baseline sky Raptor catalog Palomar 60” PQ Event Factory Event Synthesis Engine VOEvent database VOEvent. Net Pairitel known variables known asteroids 6 December 2005 2 MASS SDSS remote archives VOEvent II e. Star
Palomar-Quest Event Factory o Real-time pipeline to process raw data streaming from telescope: n n n Remove detector signatures including glitches masquerading as transient events: meteors, airplanes, glints from satellites and junk, etc. Apply basic photometric and astrometric calibration Extract detected sources and measure attributes Compare with baseline data (catalogs/images) to identify new, transient or highly variable sources Compare with dbs of known variables, asteroids, etc. 6 December 2005 VOEvent II
Architecture Palomar-Quest GRB satellites PQ next-day pipelines baseline sky Raptor catalog Palomar 60” PQ Event Factory Event Synthesis Engine VOEvent database VOEvent. Net Pairitel known variables known asteroids 6 December 2005 2 MASS SDSS remote archives VOEvent II e. Star
Event Synthesis Engine o New input arrives from PQ/elsewhere: n n n o Classify and prioritize: n n o Establish event “portfolio” to archive and federate all subsequent data and analysis Send initial event notification to subscribers Launch query against external dbs via NVO Evaluate likelihood probabilities of event being associated with possible astrophysical sources using machine learning techniques (‘Thinking Telescope’) Evaluate urgency of desired follow-up Send out VOEvent 6 December 2005 VOEvent II
Architecture Palomar-Quest GRB satellites PQ next-day pipelines baseline sky Raptor catalog Palomar 60” PQ Event Factory Event Synthesis Engine VOEvent database VOEvent. Net Pairitel known variables known asteroids 6 December 2005 2 MASS SDSS remote archives VOEvent II e. Star
VOEvent. Net Communication Fabric o o Author Publisher (aggregator): n n n o Stores packet and assigns identifier Distributes to subscribers based on pre-defined criteria using one-way web services Two dbs - Caltech for PQ and Los Alamos for Raptor - harvest each other Subscriber: n Gets event from publisher, evaluates it and causes scheduling in telescope observing queue or an archive search 6 December 2005 VOEvent II
Event Cycling o o An event can be injected back into the same decision/classification engine that published it but supplemented with data from elsewhere Events dynamically cycle through follow-up observation and computation (no humans in loop) with subscribers make judgments and adding value until convergence 6 December 2005 VOEvent II
Robotic Telescopes o RAPTOR n o PAIRITEL n o Meter-class IR follow-up P 60 n o Stereoscopic sky monitoring with followup ‘fovea’ telescope Principal follow-up facility for PQ Events e. STAR 6 December 2005 VOEvent II
Timeline o Year one - proof-of-concept system consisting of: n n o o Source of VOEvents A VOEvent store Basic event discriminator Robotic telescopic capable of responding to VOEvent: P 60 and Pairitel Year two - prototype system Year three - production system 6 December 2005 VOEvent II
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