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"3735 results found.
- GRB 120327A: MITSuME Ishigakijima Optical Upper Limits at 1 day afterthe burst
- GRB 120326A: Swift-BAT refined analysis
- GRB 120320A, Swift-BAT refined analysis
- GRB 120305A: MASTER-NET early optical observations
- GRB 120226A: Fermi-GBM and Fermi-LAT detections; LAT position retraction
- GRB 120219A: Swift-BAT refined analysis
- GRB 120211A: MITSuME Okayama and Ishigakijima Optical upper limits
- GRB 120211A: Swift detection of a burst
- LS I +61 303: Swift-BAT refined analysis
- GRB 120127A / P48 Imaging
- GRB 120127A: MASTER optical observations
- GRB 120127A: MAXI/GSC detection of a probable GRB
- GRB 120121A: Swift-BAT refined analysis
- GRB 120121A: Enhanced Swift-XRT position
- GRB 120121A: Swift-XRT position
- GRB 120121A: Swift detection of a burst
- GRB 120116A: Swift-BAT refined analysis
- GRB 111228A: GMG optical observation
- GRB 111228A: Fermi GBM observation
- Konus-Wind observation of GRB 111215B
- Possible detection of pre-trigger X-ray emission from GRB 111215A by MAXI/GSC
- GRB 111212A: GROND observations
- GRB 111209A: Swift UVOT refined analysis
- GRB 111209A: Swift Burst of Interest
- GRB 111209A: REM NIR detection
- Konus-Wind observation of GRB 111205A
- IPN Triangulation of GRB 111205A (long/hard/intense)
- GRB 111126A found in ground analysis of BAT data
- IPN Triangulation of GRB 111113A (short/hard/intense)
- XRF 111111A/MAXI J0158-744: MAXI GSC refined analysis
- XRF 111111A/MAXI J0158-744: MAXI GSC and SSC detection of a soft X-ray transient near SMC
- GRB 111109A: Swift detection of a burst
- GRB 111029A: SAO RAS optical limits
- GRB 111029A: Swift-BAT refined analysis
- GRB 111029A: Enhanced Swift-XRT position
- GRB 111024A: MAXI/GSC detection of a burst
- GRB 111022B: MITSuME Akeno Optical upper limits
- GRB 111022A: Swift-BAT refined analysis
- GRB 110905A / MAXI J1836-194: optical monitoring
- Trigger 504307: Swift detection of MAXI J1836-194
- MAXI/GSC detection of a short soft X-ray transient
- GRB 110915A: Konus-Wind and Swift/BAT joint spectral analysis
- IPN triangulation of GRB 110918A (long duration, extremely intense)
- GRB 110915A, Swift-BAT refined analysis
- GRB 110903A: Suzaku WAM observation of the prompt emission
- MAXI J1836-194 (originally GRB 110905A): Swift-BAT refined analysis
- GRB 110905A / X-ray transient MAXI J1836-194: TNT optical observation
- GRB 110905A: Potential BAT trigger on MAXI J1836-194
- Konus-Wind observation of GRB 110903A
- SGR Swift J1834.9-0846: Swift-BAT refined analysis of trigger 501752
- GRB 110801A: optical observations at Mt. Terskol observatory
- GRB 110808A: Swift/UVOT Detection
- Swift SGR 1834.9-0846: Swift-BAT refined analysis
- GRB 110807A: Swift detection of a burst or a posible new SGR
- Fermi GBM trigger 334123030 (110804165) is not a GRB
- GRB 110801A: optical observations in CrAO
- GRB 110801A: SAO RAS optical observations
- GRB 110801A: Swift-BAT refined analysis
- Swift/UVOT observations of GRB110801A
- GRB 110801A: Enhanced Swift-XRT position
- GRB 110801A: Swift detection of a burst with an optical counterpart
- Sw J1644+57 (GRB 110328A): Continued VLBA Observations
- INTEGRAL Weak trigger #6331: GRT Optical Observation
- AXP 4U 0142+61: Swift-BAT refined analysis
- GRB 110726A: Swift-BAT refined analysis
- IPN triangulation of GRB 110721A
- GRB 110715A: Swift-BAT refined analysis
- GRB 110715A: Swift detection of a bright burst with an optical counterpart
- GRB 110708A: Konkoly observations
- GRB 110709B: Preliminary Swift-BAT refined analysis
- GRB 110708A: Lick observations
- GRB 110708A: Swift/XRT afterglow candidate for the INTEGRAL burst
- SGR 1E 1841-045: Swift-BAT refined analysis
- SGR 1E 1841-045: Swift-BAT refined analysis
- GRB 110530A: Swift-BAT refined analysis
- Swift J1644+57/GRB 110328A, Additional HST Observations
- GRB 110520A: WHT IR observations
- GRB 110520A - NOT optical observation
- GRB 110520A: MASTER-NET optical observations
- GRB 110426A: Fermi GBM detection
- GRB 110503A: Swift-BAT refined analysis
- GRB 110426A: Swift/XRT non-detection
- GRB 110422A: Update of Herschel FIR observation schedule
- GRB 110426A: MASTER synchronous with MAXI/GSC observations
- GRB 110426A: MAXI/GSC detection of a GRB
- GRB 110422A: THO optical observations
- GRB 110422A: Swift-BAT refined analysis
- GRB 110420B: Swift-BAT refined analysis
- GRB 110420A: Swift-XRT refined Analysis
- GRB110414A: MITSuME Ishigakijima Optical upper limits
- GRB 110328A / Swift J164449.3+573451: WISE quiescent source upper limit
- GRB 110411A: MASTER prompt and follow-up optical limits
- GRB 110411A, Swift-BAT refined analysis
- GRB 110328A / Swift J164449.3+573451: MASTER pre, prompt and follow-up observations
- GRB 110328A / Swift J164449.3+573451: optical observations
- GRB 110328A / Swift J164449.3+573451: VLBA Observations
- GRB 110407A: MITSuME Okayama and Ishigakijima Optical upper limits
- GRB 110407A: Swift-BAT refined analysis
- GRB110328A/Swift J164449.3+573451: Fermi LAT Observations
- GRB 110402A: Swift detection of a burst