GCN Circulars
GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.
Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search
To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.
Advanced Search Examples (click to copy):
subject:"Swift"body:"GRB"submitter:"Judith Racusin"12058 results found.
- GRB 120714B: Swift/UVOT Detection
- GRB120714A: Swift/UVOT upper limits
- GRB 120714A: GROND upper limits
- GRB120714A: UVOT non-detection
- GRB120711B: MITSuME Ishigakijima upper limits
- GRB 120711A: ATCA 34GHz further observations (upper limit)
- GRB 120712A: Swift/UVOT Detection
- GRB 120711A: ATCA 34GHz upper limit
- GRB 120711B: Swift/UVOT Upper Limits
- GRB 120711A: Swift/UVOT Observations
- GRB 120709A: Swift/UVOT Observations
- Swift detection of GRB 120711B or a new Galactic transient
- GRB 120703A: Swift/UVOT Detection
- GRB 120701A: Swift/UVOT Detection
- Swift Trigger 525554 is noise
- GRB 120630A: Swift-BAT/-XRT/-UVOT refined analysis
- GRB 120624B: Swift/UVOT Upper Limits
- Watcher follow-up observations of IGR J17062-6143 (Swift trigger 525148)
- GRB 120624B: GROND upper limits
- XRF 120626B: MAXI/GSC detection
- Swift detection of Ginga 0834-430
- GRB 120624B: NOT optical upper limit
- Swift Trigger 524949: Noise fluctuation near a galaxy
- GRB 120622A: MAXI/GSC detection
- Swift triggers (#524542) on a Galactic source
- GRB 120614A: MAXI/GSC detection of a burst
- GRB 120612A: BOOTES-3 optical upper limit
- GRB 120612A: Swift detection of a burst
- GRB 120528C: MAXI/GSC detection
- GRB120521B: SSO 2.3m upper limits
- GRB 120521A: ATCA 34GHz upper limit
- GRB 120521C: EVLA 22 GHz Upper Limit
- GRB 120521A: GROND Upper limits
- GRB 120521C: Swift/UVOT Upper Limits
- GRB 120521B: Swift/UVOT Upper Limits
- GRB 120521C: MASTER optical limit
- GRB 120521B: GROND Upper limits
- GRB 120521C: PAIRITEL NIR Upper Limits
- GRB120521C: Liverpool Telescope observations
- GRB 120521C: Swift detection of a burst
- GRB 120521A: Swift/UVOT Upper Limits
- GRB120521B: Faulkes Telescope South observations
- GRB 120521B: Swift detection of a burst
- GRB 120521A: Swift detection of a short burst
- GRB 120514A: GROND upper limits
- GRB 120514A: Swift/UVOT Upper Limits
- GRB 120514A: Swift detection of a burst
- GRB 120422A: Konkoly optical observations
- GRB 120510A: MASTER follow up observations
- GRB 120510A: MAXI/GSC detection of a burst
- GRB 120427A: MASTER follow up observations
- Swift detection of 4U 1630-47
- GRB 120422A: MITSuME Ishigakijima upper limit
- GRB 120424A: MAXI/GSC detection of a burst
- GRB 120422A: Xinglong TNT optical upper limit
- GRB 120422A: A Swift/UVOT Detection
- GRB 120422A: Swift detection of a burst
- GRB 120419A: Swift-XRT and UVOT observations
- Swift Trigger 519874 is probably a noise event
- GRB 120404A: EVLA Detection
- GRB 120404A: Swift/UVOT Detection
- GRB 120401A: GROND Detection of an optical/NIR afterglow candidate
- GRB 120402B: MASTER early OT limit
- GRB 120403B: TAROT La Silla observatory optical observations
- GRB 120404A: MITSuME Akeno Optical upper limits
- GRB 120404A: MASTER early OT limit
- GRB 120403B: Swift/UVOT Upper Limits
- GRB 120403B: Swift detection of a burst
- GRB 120402A: optical upper limit
- GRB 120320A: optical upper limit in Mondy observatory
- GRB 120320A: early optical upper limit
- GRB 120403A: MASTER follow up observations
- GRB 120402A: MASTER follow up observations
- GRB 120328B: Pi of the Sky simultaneous upper limits
- GRB 120402A: Swift detection of a possible burst or noise
- GRB 120401A: Swift detection of a burst
- GRB 120324A: CrAO optical upper limit
- GRB 120328A: MITSuME Ishigakijima Optical Upper Limits
- GRB 120327A: MITSuME Ishigakijima Optical Upper Limits at 1 day afterthe burst
- The Swift-XRT source associated with trigger 518853 is a cosmic ray
- Trigger 518853: Swift detection of a probable Galactic transient
- GRB 120328A: Swift/UVOT Upper Limits
- GRB 120328A: Swift detection of a burst
- GRB 120327A: Swift/UVOT further analysis
- GRB 120323A: MASTER follow up observations
- GRB 120326A: Swift/UVOT Detection
- GRB 120323A: Fermi LAT observations
- GRB 120324A: Swift/UVOT Upper Limits
- GRB 120324A: UVOT Finding Chart Observation
- GRB 120320A: Swift/UVOT Upper Limits
- GRB 120320A: MITSuME Okayama Optical upper limits
- GRB 120320A , optical observations
- GRB 120320A: BOOTES-4 optical upper limit
- GRB 120320A: MASTER optical observations
- GRB 120320A: Swift detection of a burst
- GRB 120312A: CrAO optical upper limit
- GRB 120312A: Swift/UVOT Upper Limits
- GRB 120312A: MASTER-NET optical observations
- GRB 120311A: VLT/X-shooter observations
- GRB 120312A: Swift detection of a burst