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"- GRB 160816A: Swift ToO observations
- GRB 160816A: Fermi-LAT detection
- GRB 160815A: Swift/UVOT Detection
- Konus-Wind observation of GRB 160814A
- GRB 160815A: Swift-BAT refined analysis
- GRB 160815A: Swift-XRT refined Analysis
- GRB 160815A: Fermi GBM detection/observation
- GRB 160815A: Enhanced Swift-XRT position
- GRB 160815A: Swift/UVOT Afterglow Detection
- GRB 160815A: Swift detection of a burst
- GRB 160814A: MAXI/GSC detection
- GRB 160804B: CALET Gamma-Ray Burst Monitor detection
- IceCube 160806A: Lomonosov BDRG gamma ray prompt observations
- Fermi GBM trigger 160812507/492696620 is not a GRB
- INTEGRAL/SPI-ACS and IBIS_VETO search for prompt gamma-ray counterpart of IceCube-160806A
- Fermi GBM trigger 160810523/492525192 is not a GRB
- IceCube 160806A EHE Neutrino Candidate Event
- GRB 160806A: Fermi GBM observation
- Konus-Wind observation of GRB 160806A
- IPN Triangulation of GRB 160806A
- Swift Trigger 707517 is not an astrophysical event
- GRB160802A - Astrosat CZTI detection
- Swift Trigger 707545 is likely 4U 1850-03/GS1843-02
- Swift Trigger 707517 is probably not a GRB
- GRB 160804A: RATIR Optical and NIR Observations
- GRB 160802A: CALET Gamma-Ray Burst Monitor detection
- IceCube-160731A: Konus-Wind limits
- GRB 160804A: TSHAO optical observations
- GRB 160804A: ISON/UAFO optical observations
- GRB 160804A: GROND observations
- GRB 160804A: VLT/X-shooter redshift
- Search for counterpart to IceCube-160731A with ANTARES
- GRB 160804A: SAO RAS optical observations
- GRB 160804A: TNG optical observations, afterglow fading and candidate host galaxy
- GRB 160804A: Fermi GBM observation
- GRB160804A: MASTER-SAAO observation
- Konus-Wind observation of GRB 160802A
- IPN Triangulation of GRB 160802A
- GRB 160804A: Swift-BAT refined analysis
- GRB 160804A: Swift/UVOT Detection
- GRB 160804A: Swift-XRT refined Analysis
- GRB 160804A: Enhanced Swift-XRT position
- GRB 160804A: Swift detection of a burst
- IceCube-160731A: iPTF P48 Observations
- GRB 160802A: Lomonosov BDRG gamma ray detection
- GBM Observations of IceCube 160731
- GRB 160801A: TSHAO optical observations
- GRB 160801A: Swift/UVOT Upper Limits
- GRB 160801A: SAO RAS optical observations
- GRB 160802A: Fermi GBM detection
- GRB 160801A: NOT upper limits
- FACT follow-up of IceCube20160731
- GRB 160726A: CALET Gamma-Ray Burst Monitor detection
- GRB 160801A: Swift-XRT refined Analysis
- GRB 160801A: Swift-BAT refined analysis
- Global MASTER net follow up of IceCube-160731A
- Swift follow up of IceCube-160731A
- GRB 160801A: Enhanced Swift-XRT position
- GRB 160801A: MITSuME Okayama upper limits
- GRB 160801A: Swift detection of a burst
- HAWC follow up of IceCube 160731
- GRB 160716A: TAROT La Silla observatory optical observations
- GRB160720A: Astrosat CZTI detection
- GRB160709A: Astrosat CZTI detection of short GRB
- GRB160703A: Astrosat CZTI detection
- GRB 160705B: 15 GHz upper limits from AMI
- GRB 160703A: 15 GHz upper limits from AMI
- GBM observation of SGR-like burst from the direction of PSR 1119-6127
- Trigger 706396: Swift detection of a short burst from PSR 1119-6127
- GRB 160726A, Swift-BAT refined analysis
- Konus-Wind observation of short GRB 160726A
- GRB 160726A: Fermi GBM observation
- GRB 160726A: Swift detection of a short burst
- GRB 160721A: CALET Gamma-Ray Burst Monitor detection
- GRB 160720A CALET Gamma-Ray Burst Monitor detection
- GRB 160720A: Lomonosov BDRG gamma ray detection and MASTER limit
- Konus-Wind observation of GRB 160720A
- IPN Triangulation of GRB 160720A
- GRB 160703, GRB 160705, GRB 160720, SGR1935+2154: First SGRs and GRBs detected by Lomonosov.
- GRB 160720A: Fermi GBM detection
- Fermi GBM trigger 490701713/160720418 is not a GRB
- Fermi GBM trigger 490365157/160716523 is not a GRB
- GRB 160716A: Swift/UVOT Detection
- GRB 160714A: Swift/UVOT Upper Limits
- GRB 160716A: Swift-BAT refined analysis
- GRB 160716A: Swift-XRT refined Analysis
- GRB 160716A: Enhanced Swift-XRT position
- GRB 160716A: Swift detection of a burst
- Swift Trigger 704327: KAIT Optical Observations
- Swift Trigger 704444 is probably not an astrophysical event.
- GRB 160712A: Swift-BAT refined analysis
- GRB 160714A: TAROT Calern observatory optical observations
- GRB 160714A: Swift-XRT observations
- GRB 160623A: afterglow spectroscopy by GTC and independent redshift determination
- GRB 160714A: Fermi GBM observation
- GRB 160623A: optical astrometry, photometry, and redshift
- Swift-BAT trigger 704327 was due to noise
- Fermi GBM trigger 490193747/160714539 is not a GRB
- GRB 160714A: Swift-BAT refined analysis,
- Swift Trigger 704327: MASTER syncronous optical observations