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"8473 results found.
- GRB 110503A: Swift-BAT refined analysis
- GRB 110503A: Swift detection of a burst with a bright optical counterpart
- GRB 110422A: Swift detection of a burst
- GRB110420A: GROND detection of the Optical/NIR Afterglow Candidate
- GRB 110420B: Swift-XRT afterglow candidate retraction
- GRB 110420B, GROND observations
- GRB 110420B: Swift-XRT afterglow candidate
- GRB 110420B: Swift-BAT refined analysis
- GRB 110420A: Swift detection of a burst with optical counterpart
- GRB 110414A: Swift detection of a burst
- GRB 110411A: PAIRITEL NIR Upper Limits
- GRB 110412A: Swift-BAT refined analysis
- GRB 110411A: MASTER prompt and follow-up optical limits
- GRB 110411A : Xinglong TNT OT candidate
- GRB 110411A: Swift detection of a burst
- GRB 110407A : Lulin optical afterglow detection
- GRB 110407A: Swift detection of a burst
- Konus-Wind observation of GRB 110406A
- ICSP VLF observation of multiple SGR-like bursts from 1E 1841-045 on Feb. 9, 2011
- GRB 110402A: Swift/UVOT detection of afterglow candidate
- GRB 110402A: Konkoly observations
- GRB 110402A: Swift detection of a burst
- GRB 110328A: Swift detection of a burst
- GRB 110319B BAT refined analysis
- GRB 110319B: GROND upper limits
- GRB 110319B: Swift-XRT afterglow candidate.
- GRB 110319A: Swift detection of a burst
- GRB 110318B: Swift/UVOT Non-Detection of an Afterglow
- GRB 110315A: Swift detection of a burst
- GRB 110312A: Swift detection of a burst
- GRB 110301A: Fermi GBM detection
- No IPN GRB detected in conjunction with candidate GRB 110215
- GRB 110223A: Swift-BAT refined analysis
- GRB 110223B: GROND Detection of Optical Afterglow Candidate
- GRB 110223B: Swift detection of a burst
- GRB 110223A: Swift detection of a burst
- OT 110215: Further NIR observations from NOT of the GRB candidate
- Fermi GBM detection of an SGR-like burst
- OT 110215: NIR observations from NOT of GRB candidate
- GRB 110213B: Gemini South Redshift
- GRB 110213B: Possible Host Galaxy in SDSS Stripe 82 Imaging
- GRB 110213B: P60 Optical Afterglow Candidate
- GRB 110212A: Swift XRT and UVOT observations
- GRB 110213B: Swift XRT observation
- GRB 110213A: Swift detection of a burst with optical afterglow
- GRB 110210A: Swift detection of a burst
- Fermi GBM detection of a burst from 1E 1841-045
- GRB 110206A: SMARTS optical/IR afterglow decay
- GRB 110208A: Swift detection of a burst
- SGR-like outburst from the magnetar 1E 1841-04.5
- GRB 110206A: Decay of afterglow candidate
- GRB 110206A: SMARTS optical/IR afterglow candidate observations
- GRB 110206A: GROND detection of afterglow candidate
- GRB 110205A: WSRT radio observation
- GRB 110206A: UVOT detection of afterglow candidate
- GRB 110205A: Newcastle Observatory Optical Observations
- GRB 110205A: Liverpool Telescope Afterglow Confirmation
- GRB 110205A: TAROT Calern observatory optical detection
- GRB 110205A: Swift detection of a burst with an optical candidate
- GRB 110201A: Swift detection of a burst
- GRB 101112A: Maidanak and CrAO optical observations
- GRB 110128A: Swift detection of a burst
- GRB 110106A: CrAO optical observations
- GRB 110119A: Swift detection of a burst with an optical detection
- GRB 101219B: tentative redshift and spectroscopic supernova detection
- Swift-BAT trigger 442771 is a noise fluctuation
- Swift Trigger 442539 is probably not a GRB
- GRB 110112B: Swift XRT and UVOT observations of the INTEGRAL burst
- GRB 110112A: WHT candidate afterglow/host galaxy
- GRB110112A: TNT optical afterglow candidate
- GRB 110112A: Swift detection of a possible short burst
- GRB 110107A: Swift-XRT Afterglow Candidate
- GRB 110106B: Gemini-North / WHT detection of a fading afterglow
- GRB 110106B: WHT candidate afterglow
- GRB 110106B: Swift detection of a burst
- GRB 110106A: TNG optical observations and candidate counterparts
- GRB 110106A: MASTER optical observations
- GRB 110106A: Swift detection of a burst
- GRB 101219A: Gemini-North host redshift
- GRB 101219B: After 2 weeks still detected by Swift/UVOT
- GRB110102A: MITSuME Okayama Optical Observation
- GRB 110102A: Swift detection of a burst with an optical detection
- GRB 101225A: P60 Observations
- Trigger 441015 / GRB 101225A: NOT optical afterglow candidate
- GRB 101224A: Swift detection of a short burst
- GRB 101219B: GROND Detection of the Optical/NIR Afterglow
- GRB 101219B: Swift detection of a burst with an optical afterglow
- GRB 101219A: GROND Upper limits
- GRB 101219A: SARA-N Upper Limit
- GRB 101219A: Swift detection of a short hard burst
- Redshift solution(s) for GRB101213A from Swift-XRT data
- GRB 101213A: Fermi GBM observation
- GRB 101213A: Swift detection of a burst
- GRB101204A: Swift/UVOT observations
- GRB101204A GROND Detection of the Optical/NIR Afterglow
- GRB 101204A Afterglow Candidate, VATT Observations
- GRB 101204A Swift-XRT/UVOT afterglow candidate
- GRB 101123A: ROTSE optical observations
- GRB 101117B: Swift detection of a burst
- GRB 101114A: Swift-XRT candidate afterglow detection and analysis