In addition to the information on this page, please also see the Lasair Cookbook.
You can query the alerts with a freeform SQL interface (select Query Objects). The Cone Search finds an object by position. You can see the coverage of the ZTF survey each night (click Coverage). A Watchlist is a collection of sky positions that you find interesting, and Lasair can do cone searches on all of these together. Power users can use a Jupyter notebook interface, click Jupyter for more information and to see the capabilities.
|ZTF photometry is measured after subtraction of a template image. Thus the reported magnitudes correspond to the difference in flux with respect to the template. Positive differences are shown as solid symbols, negative differences are shown as empty symbols. For variable (rather than transient) sources, reported magnitudes here can therefore be significantly fainter than the average magnitude of the source. See image at right.|
|Conesearch: You can copy and paste a position from Astronomer's Telegram or elsewhere to see if Lasair has a light curve for that source.|
|Rich Object Information: The light curve of each object is shown in two filters (g and r), with both detections and non-detections, in this case for supernova 2018jny / ZTF18acsovsw. Comments can be added by logged-in users, such as this one with the link to the IAU name of the supernova. The Sherlock classificaiton system has provided information about the host galaxy. Aladin Lite provides both images and catalogue sources: here we see Pan-STARRS image of the host galaxy with sources from Pan-STARRS and Gaia DR2|
|Detection Images: The object page has links to detailed information about each observation that makes up the light curve, with images, in this case for ZTF18acsovsw. We see the brightening of 2018jny.|
|Rich Query Capability: Lasair provides free-form SQL query access to the database. Available tables include the ZTF objects and candidates (detections), as well as the classification of the object from Sherlock and the comment list. Logged-in users can contribute useful queries which can then be re-used by others.|
|Watchlists: A watchlist is a collection of sources in the sky that can be created by a logged-in user, that can be private or public. The "Run Crossmatch" button searches the Lasair database for transients coincident with any of those sources. Here we see a catalogue of Cataclysmic Variables (left side of the table), and the associated Lasair sources (right side). The inset shows the light curve foe one of the CVs.|
|Coverage: The coverage of the survey can be seen against a variety of all-sky images from Aladin Lite. Green squares are for g filter (401.5–551.9 nm) and red squares for r filter (552.0–691.0 nm).|
|Sherlock Classification: The Sherlock system crossmatches every Lasair transient against many catalogues, classifying it, and producing a natural-language assessment of the object, that is available on the object page.|
|Skymaps: Gravitational-wave skymaps from LIGO-Virgo are represented as a contour map of percentiles 10%, 20%, ... 90%. ZTF coverage and detections can be overlaid, as well as galaxies where the counterpart might reside, with the area of the yellow square proportional to the probability. A doubleclick inside the square centres the galaxy for zooming, and shows its distance and a NED link above.|