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"23571 results found.
- GRB 090812, RIMOTS optical upper limits
- GRB 090812 Swift-BAT Refined Analysis
- GRB090812: Swift/UVOT observations
- GRB 090812: GROND Observations of the Optical/NIR Afterglow
- GRB 090812: Liverpool Telescope afterglow confirmation
- GRB 090812: P60 Confirmation of Optical Afterglow
- GRB 090812: Swift detection of a burst with an optical counterpart
- GRB 090621B: MAGIC telescope GeV observation
- GRB 090621A: MAGIC telescope GeV observation
- GRB 090809: Swift-BAT refined analysis
- GRB 090809: Swift detection of a burst with a possible optical counterpart
- GRB 090807: Liverpool Telescope observations
- GRB 090807: MITSuME optical upper limit
- GRB 090807, Swift-BAT refined analysis
- GRB 090807: Swift detection of a burst
- IPN Triangulation and Konus-Wind observaions of GRB090727B
- Swift-BAT trigger 358760 is most likely not a GRB
- Swift trigger 358760 is probably a noise event
- GRB 090717A: Suzaku WAM observation of the prompt emission
- GRB 090709A : Quick look analysis of the Suzaku observation
- GRB 090728: Swift-BAT refined analysis
- GRB 090727: optical observations
- GRB 090727: I-band observations from 1.23m CAHA
- GRB 090728A: Faulkes Telescope North Optical Afterglow Candidate
- GRB 090728: Swift detection of a burst
- GRB 090727: Swift-BAT refined analysis
- GRB 090727: Liverpool Telescope possible OT candidate
- GRB 090727: Swift detection of a burst
- GRB 090726, Swift-BAT refined analysis
- GRB 090711: Fermi GBM detection
- GRB090726: 6-meter telescope redshift
- GRB 090726: optical transient candidate
- GRB 090726: Swift/UVOT Finding Chart Observation
- GRB 090726: Swift detection of a burst
- Swift Trigger 358354 is not a GRB
- Konus-Wind and Konus-RF observations of GRB 090719
- Konus-RF and Konus-Wind observations of GRB 090718B
- Konus-Wind observations of bright hard GRB 090720B
- IPN Triangulation of bright GRB 090720B
- GRB 090720B: Fermi GBM detection
- GRB 090720 Source found in ground processing of Swift-BAT data
- GRB 090717B: Fermi GBM detection
- GRB 090717: Fermi GBM detection
- GRB 090719: Fermi GBM detection
- GRB 090720: Fermi GBM detection
- GRB 090715A: Suzaku WAM observation of the prompt emission
- GRB 090715B: Lick observations
- Konus-Wind observations of short/hard GRB 090715A
- GRB 090715B: MASTER optical limit
- GRB 090715A: Swift-BAT refined analysis
- Konus-Wind and Konus-RF observations of GRB 090715B
- GRB 090715B: Observation of the optical afterglow
- GRB 090715B: Swift-BAT refined analysis
- GRB 090715B - Liverpool Telescope Optical Afterglow Candidate
- GRB 090715B: Swift detection of a burst with a possible optical counterpart
- GRB 090715: Swift detection of a short hard burst
- Detection of GRB 090618 by RT-2 Experiment onboard the CORONAS-PHOTON Satellite
- GRB 090713: Fermi GBM detection
- GRB 090712: Swift-BAT refined analysis
- GRB 090712: Swift detection of a burst
- GRB 090709A: deep optical observation with the 10.4m GTC
- GRB 090709A: Suzaku WAM observation of the prompt emission
- GRB 090709B: Fermi GBM detection
- GRB 090709A: confirmation of the periodicity in the SPI-ACS data
- GRB 090709A: evidence for a very red afterglow at low z
- Konus-Wind and Konus-RF observations of GRB 090709A
- GRB 090709A: Quasiperiodic variations in the BAT light curve
- GRB 090709B, Swift-BAT refined analysis
- GRB 090709A: Swift-BAT refined analysis
- GRB 090709A: Enhanced Swift-XRT position
- GRB 090709A: Subaru NIR observation
- GRB 090709B: Swift detection of a burst
- GRB 090626: Suzaku WAM observation of the prompt emission
- GRB 090704: Fermi GBM observation
- GRB 090709: Swift detection of a bright burst
- GRB 090708, Swift-BAT refined analysis
- GRB 090708: Swift detection of a burst
- GRB 090704: a long GRB found in INTEGRAL off-line analysis
- GRB 090706: Fermi GBM detection
- Swift-BAT trigger 356516 is not a GRB
- Possible GRB090705: Swift-XRT observations
- GRB 090705: Swift detection of a possible burst
- XRF 090702 : RTT150 optical observations
- GRB 090529: Mt.Terskol optical observations
- XRF 090702: Swift-XRT refined analysis
- GRB 090702: UVOT upper limits
- XRF 090702: VLT imaging
- XRF 090702: a long soft GRB localized with INTEGRAL
- GRB 090701: Fermi GBM detection
- GRB 090630: Fermi GBM detection
- GRB 090618: RTT150 optical observations
- GRB 090628: Swift/UVOT Upper Limits
- Konus-Wind observation of GRB 090626
- GRB 090628: Swift-BAT refined analysis
- GRB 090628: GROND upper limits
- GRB 090628: 1.23m CAHA optical observations
- GRB 090626: IPN localization
- GRB 090628: Swift detection of a burst
- GRB 090623: Suzaku WAM observation of the prompt emission
- GRB 090625B: Faulkes Telescope South observations