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.
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"12320 results found.
- GRB 120119A: optical upper limit
- GRB 120121A: Swift/UVOT Upper Limits
- GRB 120121A: Swift detection of a burst
- GRB 120119A: Swift/UVOT Observations
- GRB 120118B: Swift/UVOT Upper Limits
- GRB 120118B: MASTER optical observations
- GRB 120118B: Swift detection of a burst
- GRB 120116A: Swift/UVOT Upper Limits
- GRB 120116A: MASTER Early optical limit
- GRB 120116A: Swift detection of a burst
- GRB 120106A: optical upper limit
- Swift detection of an SGR burst from AXP 4U 0142+61
- GRB 120106A: MITSuME Okayama Optical Observation (update)
- GRB 120106A: Swift/UVOT Upper Limits
- GRB 120106A: MITSuME Okayama Ks-band upper limit
- INTEGRAL Weak trigger #6433: GRT Optical Observation
- GRB 120106A: MITSuME Okayama Optical upper limits
- GRB 120106A: MASTER-Tunka optical observations
- GRB 120106A: Swift detection of a burst
- GRB 111222A: Second Swift observation
- Konus-Wind observation of GRB 120102A
- GRB 120102A: Swift/UVOT Detection
- GRB 111229A: Swift/UVOT Detection
- GRB 111225A: Lightbuckets Optical Observations
- FERMI GRB111228.45: MASTER observations
- GRB 111228A: Swift/UVOT Detection
- GRB 111225A, optical observations
- GRB 111225A: Swift/UVOT Observations
- GRB 111225A: PAIRITEL NIR Upper Limits
- GRB111225A: MITSuME Okayama optical upper limits
- GRB 111225A: GRT Optical Observation
- GRB 111210A: optical upper limit of Mt. Terskol observatory
- Trigger 510075 is not a GRB
- GRB 111103B: optical upper limit
- GRB 110820A: optical observations in Maidanak observatory
- GRB 111103A: optical upper limit of Mt. Terskol observatory
- GRB111215A: optical upper limit
- GRB 111215B: Swift/UVOT Upper Limits
- GRB 111215A: MITSuME Okayama Optical upper limits
- GRB 111215A: Swift/UVOT Upper Limits
- GRB 111215A: MASTER-Net optical prompt and follow up observations
- GRB 111215A: MITSuME Akeno Optical upper limits
- GRB 111215A: GMG optical upper limit
- GRB 111215A : Xinglong TNT upper limit
- GRB 111215A: Swift detection of a burst
- GRB 111212A: Swift/UVOT Upper Limits
- GRB 111210A: Xinglong TNT upper limit
- GRB 111209A - ATCA 34GHz upper limit
- GRB 111210A: GROND observations
- GRB 111210A: MITSuME Okayama Optical upper limits
- GRB111210A: MITSuME Okayama J-band upper-limit
- GRB 111210A: Swift/UVOT Upper Limits
- GRB 111210A: Swift detection of a burst
- GRB 111208A: Lightbuckets Optical Observations
- GRB 111208A: Swift XRT/UVOT observations
- Konus-Wind observation of GRB 111205A
- GRB 111204A: GROND Observations
- GRB 111204A: Swift/UVOT Upper Limits
- GRB 110921A: optical observations in Maidanak observatory
- GRB 111204A: MASTER optical observations
- GRB 111123A: optical upper limit in CrAO: correction to the GCN circ. 12613
- GRB 111123A: optical upper limit in CrAO
- GRB 111204A: Swift detection of a burst
- GRB 111201A: Swift/UVOT Upper Limits
- GRB 111129A: Swift/UVOT Detection
- GRB 111123A: Swift/UVOT Upper Limits
- GRB 111123A, GROND observations
- GRB 111123A: correction to GCN 12593
- GRB 111123A: TNG NIR detection of the afterglow candidate
- GRB 111123A: MITSuME Okayama Optical upper limits
- GRB 111123A: Swift detection of a burst
- GRB 111121A: Swift/UVOT Upper Limits
- GRB 111117A: optical upper limit in CrAO
- GRB 111117A: Swift/UVOT Upper Limits
- GRB 111117A: GMG upper limit
- GRB 111117A: Swift detection of a short hard burst
- GRB111107A: ATCA observations - upper limit and a possible detection
- XRF 111111A/MAXI J0158-744: MAXI GSC and SSC detection of a soft X-ray transient near SMC
- GRB 111103B: optical upper limit of CrAO
- GRB 111103B: optical upper limit of Mt. Terskol observatory
- GRB 111107A: Swift/UVOT Afterglow Analysis
- GRB 111103B: MITSuME Akeno Optical upper limits
- GRB111103B Swift/UVOT Upper Limits
- GRB 111022B: MASTER OT observations
- GRB 111103B: optical observations
- GRB 111103B: Swift detection of a strong burst from a GRB or Galactic source
- GRB111029A: MITSuME Ishigakijima Optical Upper Limits
- GRB 111029A: TNT optical upper limit, Correction to GCN 12503
- GRB 111029A: PAIRITEL NIR Upper Limits
- GRB 111029A: Swift/UVOT Upper Limits
- GRB 111029A: TNT optical upper limit
- GRB 111029A: optical upper limit
- GRB 111022B: EVLA observations - correction to GCN 12495
- GRB 111022B: EVLA observations
- GRB 111022A: MITSuME Akeno Optical upper limits
- GRB 111024A: MAXI/GSC detection of a burst
- GRB 111022B: Swift/UVOT upper limits
- GRB 111022A: Swift/UVOT Upper Limits
- GRB 111016A: optical upper limit
- GRB 111022B: MITSuME Akeno Optical upper limits