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 160908A: CALET Gamma-Ray Burst Monitor detection
- GRB 160910A: Fermi-LAT detection
- GRB 160910A: Fermi GBM observation
- Konus-Wind observation of GRB 160905A
- GRB 160824A: 15 GHz upper limits from AMI
- GRB 160821B: 15 GHz upper limits from AMI
- GRB 160905A: Swift/UVOT Detection
- GRB 160905A: Swift-BAT refined analysis
- Swift Trigger 711158 is not an astrophysical event
- GRB 160905A: Swift-XRT refined Analysis
- GRB 160821A: 15 GHz upper limits from AMI
- GRB 160816A: Possible radio afterglow detection at 15 GHz with AMI
- GRB 160905A: Enhanced Swift-XRT position
- GRB 160905A: Fermi-LAT detection
- GRB 160905A: Fermi GBM observation
- IceCube HESE 160814: MASTER OT J130845.02-323254.9 as the possible source of the high energy neutrino
- GRB 160905A: Swift detection of a burst with an optical counterpart
- Fermi GBM trigger 494508549 / 160902479 is not a GRB
- Search for counterpart to IceCube-160814A with ANTARES
- GRB 160824B: Lomonosov BDRG gamma ray detection and MASTER limit
- GRB 160829A: Swift-XRT observations
- GRB 160829A: Fermi GBM Detection
- GRB 160816A, the review of the sky area in plate archives
- GRB 160829A: Swift ToO observations
- GRB 160829A: Fermi-LAT detection of a short GRB
- GRB 160827A: Swift-BAT refined analysis
- Swift trigger 710022 is not astrophysical
- GRB 160827A: Swift detection of a burst
- Correction to Circular 19874 (on Swift trigger 71022)
- Swift Trigger 710022 is very likely noise
- GRB 160824B: CALET Gamma-Ray Burst Monitor detection
- GRB 160826A: Swift-BAT refined analysis
- GRB 160826A: Swift/UVOT Upper Limits
- GRB 160825A: not localized by Swift
- GRB 160820A: Fermi GBM observation
- GRB 160826A: Swift-XRT refined Analysis
- GRB160821A: Astrosat CZTI (veto) detection
- GRB 160826A: Swift detection of a burst
- GRB 160821A: CALET Gamma-Ray Burst Monitor detection
- GRB 160825A: Swift ToO observations
- GRB 160824A: 1.5m OSN I-band observation
- GRB 160824A: ISON/Terskol optical observations
- GRB 160824A: Swift-BAT refined analysis
- GRB 160824A: Swift/UVOT Possible Afterglow Detection
- GRB 160824A: Bassano Bresciano Observatory upper limits
- GRB 160824A: Swift-XRT refined Analysis
- GRB 160824A: Enhanced Swift-XRT position
- GRB 160824B: Fermi GBM detection
- GRB 160824A: Swift detection of a burst
- GRB 160821B: VLA 5.0 GHz observations
- Konus-Wind observation of GRB 160822A
- IPN Triangulation of GRB 160822A (short/hard)
- Konus-Wind observation of GRB 160820A
- IPN Triangulation of GRB 160820A (short/hard)
- Possible radio detection of GRB160703A with the GMRT
- Possible radio detection of GRB160623A with the GMRT
- GRB 160821B: GTC follow-up observation
- GRB 160821B: WHT afterglow confirmation and redshift of candidate host
- GRB 160822672: Fermi GBM detection
- GRB 160821B: Swift-BAT refined analysis
- GRB 160821B: Fermi GBM Detection
- Konus-Wind observation of GRB 160821A
- GRB 160821B: Swift-XRT refined Analysis
- GRB 160821A: Swift-BAT refined analysis
- GRB 160821B: Swift/UVOT Upper Limits
- Short GRB 160821B: MASTER early optical observations
- GRB 160821B: Enhanced Swift-XRT position
- GRB 160821A: Fermi-LAT refined analysis
- GRB 160821A: Fermi GBM Detection
- GRB 160821B: NOT optical afterglow candidate
- GRB 160821B: Swift detection of a short burst
- GRB 160821A: TAROT Calern observatory optical detection
- GRB 160821A: Fermi-LAT detection of a bright burst
- GRB 160821A: Swift detection of a bright burst
- GRB 160816A: TSHAO optical observations
- INTEGRAL/SPI-ACS observation of IceCube HESE 128340 58537957
- BAT detection and localization of GRB 160819A
- GRB 160819A: Fermi GBM detection
- GRB 160816A: ISON/UAFO optical observations
- GRB 160816A: Further RATIR Optical and NIR Observations
- GRB 160815A: CALET Gamma-Ray Burst Monitor detection
- IBAS Alert 7534: Not a real GRB
- GRB 160816A: MASTER OT early detection on coaded images
- GRB 160816A: RATIR Optical and NIR Afterglow Confirmation
- GRB 160816A: confirmed fading with the LT
- GRB 160816A iTelescope observation
- Fermi GBM Observations of IceCube-160806A
- GRB 160814A: CALET Gamma-Ray Burst Monitor detection
- GRB 160816A: Swift/UVOT Detection
- GRB 160816A: IPN annulus
- GRB 160804A: 15 GHz detections and upper limit from AMI
- GRB 160801A: 15 GHz upper limits from AMI
- GRB 160714A: 15 GHz upper limits from AMI
- Konus-Wind observation of GRB 160816A
- GRB 160816A: RATIR Optical and NIR Observations
- GRB 160816A: LCOGT-FTN optical candidate
- GRB 160815A: GWAC-F60A upper limit
- GRB 160816A: Swift-XRT afterglow detection
- GRB 160816A: MASTER inspection
- GRB 160816730A: Fermi GBM detection/observation