1. Hotwiring the Transient Universe Understanding and Annotating LIGO-Virgo Probability Maps Roy Williams LIGO Lab - Caltech

2. Hotwiring the Transient Universe How to get your Nobel Prize for the GW-EM counterpart Apply to join the MOU group herehere – When approved register herehere Ask GCN to allow your IP-address to connect – send email to Scott and Teresa (section 1 here)here Login to event database (Gracedb) herehere – and get a password (section 2 here)get a passwordhere When VOEvent / GCN-Notice arrives, get the skymap – using your password – View it with Skymap ViewerSkymap Viewer – or process it with healpyhealpy – or with pygcnpygcn If you observe, share footprints at Gracedb May 15, 2015G1500607

3. Hotwiring the Transient Universe How is LIGO followup different? The Skymap Not a position. A probability distribution represented with FITS/Healpix healpix.jpl.nasa.gov sudo pip install healpy EA in HEALPIX means all pixels on the sphere have equal area sample code and tech info herehere Should I observe? If so, where? May 15, 2015G1500607

4. Hotwiring the Transient Universe Next.... Skymap Viewer Here is the open version with 1600 mock skymaps Here Here for MOU partners Here direct link from Gracedb And sharing footprints like the minor planet center don't observe what is already covered we want to ask for the image itself if we need to May 15, 2015G1500607

5. Hotwiring the Transient Universe Skymap Viewer May 15, 2015G1500607 N S E W moon view from Tasmania Observations so far

6. Hotwiring the Transient Universe Image and Catalog May 15, 2015G1500607 Click on the Layers icon WHAT OTHER CATALOGS HERE?

7. Hotwiring the Transient Universe May 15, 2015G1500607 size of square is ~galaxy mass * skymap click the center to get Simbad and NED 70 Mpc

8. Hotwiring the Transient Universe Zoom and drilldown May 15, 2015G1500607 set image = DSS colored keep zooming in ESO336-016 click the marker then NED link much more data (eg 2MASS image) zoom control

9. Hotwiring the Transient Universe Gracedb: the LIGO event database Communication: Click, Curl, or Code? clicking allows reading, experiment, understanding a curl command is automatable and transparent a code library integrates well with other code – try pygcnpygcn Curl example May 15, 2015G1500607 curl --insecure --netrc https://gracedb.ligo.org/gracedb/apibasic/events/M137112/files/bayestar.fits.gz > M137112_bayestar.fits.gz

10. Hotwiring the Transient Universe Reading a Skymap Reading a skymap file Healpix/FITS – Process with healpy – View with Skymap Viewer (convert to json and load)convert to json load May 15, 2015G1500607 map,header = healpy.read_map(filename, h=True) # map is a long vector of floats # header is dictionary of FITS header # interpolate # th is codeclination (radians), ph is RA (radians) probability = healpy.pixelfunc.get_interp_val(map, th, ph) # handle every pixel nside = healpy.get_nside(map) (th, ph) = healpy.pix2ang(nside, i) probability = map[i]

11. Hotwiring the Transient Universe Using Gracedb for Sharing EM followup Shared messages from LV-EM partners GCN Circulars EM Observations Footprints (required by MOU) Candidates Visualizing shared effort May 15, 2015G1500607 From the MOU

12. Hotwiring the Transient Universe Using Gracedb for Sharing May 15, 2015G1500607 gracedb.ligo.org collapse the Event Log Messages open the "EM followup" and "EM Observations" Like GCN Circulars (includes them) observation footprints

13. Hotwiring the Transient Universe Sharing observation footprints May 15, 2015G1500607 comma-separated RA, Dec lists RAwidth, Decwidth can be list You don't need to click a web form you can build a curl command use pygcn click, curl, or code

14. Hotwiring the Transient Universe Footprints in Skymap Viewer May 15, 2015G1500607 Open the "Sky Localization" tab Click the gray button

15. Hotwiring the Transient Universe Footprints in Skymap Viewer May 15, 2015G1500607

16. Hotwiring the Transient Universe Helping the follow-uppers Nearby galaxy catalogs To ~200 Mpc Got any more? Galaxy cluster catalogs Suggestions welcome But most galaxies not in clusters Light curves has this object been variable before forced photometry services from surveys? May 15, 2015G1500607

17. Hotwiring the Transient Universe Helping the follow-uppers Most likely galaxies Catalog with rate prior (eg galaxy luminosity) Multiply by skymap probability Ordered list of your fields Sky tesselated into YOUR rectangular fields – which have most dark sky + probability? Personal alarm for GW events When YOUR telescope has a chance – dark sky + probability > X steradians May 15, 2015G1500607