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"26159 results found.
- GRB 100905A: Swift detection of a burst
- GRB 100902A: GROND observations; afterglow candidate
- GRB 100904A: Swift-BAT refined analysis
- GRB 100904A: Swift detection of a burst
- GRB 100902A: Swift-BAT refined analysis
- IPN Triangulation of the very bright GRB 100829A
- GRB 100901A: Lightbuckets Optical Observations
- Tentative redshift of GRB100902A from Swift-XRT data
- GRB 100902A: Swift XRT refined analysis
- GRB 100902A: Swift/UVOT Upper Limits
- GRB 100902A: MASTER Prompt Optical Observations
- GRB 100902A: Faulkes Telescope South observations
- GRB 100902A: MASTER Optical Early Limit
- GRB 100902A: Swift detection of a burst
- GRB 100901A: ROTSE-III Detection
- GRB 100901A: MASTER optical flare at 420s discovery
- GRB 100901A: Vega telescope optical afterglow observation
- Swift/UVOT Observations of GRB100901A
- GRB 100901A: SARA-N observations
- GRB 100901A: Swift-XRT Team refined analysis
- GRB 100901A - NOT optical observation
- GRB 100901A: Swift-BAT refined analysis
- GRB 100901A: MASTER Optical Early Limits
- GRB 100901A: Faulkes Telescope North afterglow candidate
- GRB 100901A: Swift detection of a burst with an optical afterglow
- GRB 100829.9: MASTER Optical Limits
- GRB100826A: Fermi-LAT Observations
- GRB 100823A: MAXI/GSC detection
- GRB100807A: R band observations
- GRB 100823A: Swift XRT refined analysis
- GRB 100823A: Swift/UVOT Upper Limits
- GRB 100823A: Swift-BAT refined analysis
- GRB 100823A: Swift detection of a burst
- GRB 100814A: Suzaku WAM observation of the prompt emission
- GRB 100814B: Fermi GBM detection
- Konus-Wind observation of GRB 100816A
- GRB 100816A: Fermi GBM observation
- Konus-Wind observation of GRB 100814A
- GRB 100814A : Lulin optical observation
- GRB 100816A: Swift UVOT Observations
- GRB100816A Swift-XRT refined analysis
- GRB 100816A, Swift-BAT refined analysis
- GRB 100816A: CQUEAN riz-band Detection, Host Galaxy?
- GRB100814A - interesting UVOT lightcurve.
- GRB 100816A: TAROT Calern observatory optical detection
- GRB 100816A: MASTER Optical Limits
- GRB100816A: TNG optical afterglow confirmation.
- GRB 100816A: ROTSE-III Optical Limits
- GRB 100816A: Swift detection of a possibly short burst with optical afterglow
- Swift-BAT trigger 431756 is not a burst
- GRB 100814A: Fermi GBM observation
- GRB 100814A: Swift-XRT refined analysis
- Swift/UVOT observations of GRB100814A
- GRB 100814A, Swift-BAT refined analysis
- GRB 100814A: CQUEAN r- and i-band Observation
- GRB 100814A: GROND Detection of the Optical/NIR Afterglow
- GRB100814A: Magellan Echellette Observations
- GRB 100814A: Swift UVOT observations of the optical afterglow
- GRB 100814A: Swift detection of a burst with an optical afterglow
- GRB 100814A: ROTSE-III Detection of Optical Counterpart
- Swift-BAT trigger 431582 likely is IGR J17464-2811
- GRB 100805A: optical observation in CrAO (correction to the GCN 11077 and second epoch)
- GRB 100805A: Swift/UVOT Observations of a Possible Late-Time Brightening
- GRB 100807A: P200 Infrared Observations
- GRB 100807A: Swift XRT refined analysis
- GRB 100807A: P60 Optical Afterglow Discovery
- GRB 100807A: Swift/UVOT Upper Limits
- GRB 100807A: Swift-BAT refined analysis
- GRB 100807A: ROTSE-III Optical Limits
- GRB 100807A: Swift detection of a burst
- GRB 100805A: Early RAPTOR Observations
- GRB 100805A: Swift/UVOT Observations of the Optical Afterglow
- GRB 100802A: WIYN observations
- Swift-BAT trigger 430975 is not a burst
- GRB 100805A: Swift-BAT refined analysis
- GRB 100805A: Swift-XRT Refined Analysis
- Trigger 430975: Swift detection of a possible burst
- GRB 100805A: Liverpool Telescope afterglow observations
- GRB 100805A: P60 Optical Afterglow Candidate
- GRB 100805A: ROTSE-III Optical Limits
- GRB 100805A: Swift detection of a burst with an optical counterpart
- GRB 100802A: Fermi GBM observation
- GRB 100802A: NOT optical observation
- GRB 100802A: P60 Observations
- GRB 100802A: XRT refined analysis
- GRB 100802A: Swift/UVOT Possible Optical Afterglow
- GRB 100728A: Suzaku WAM observation of the prompt emission
- GRB 100802A: Swift-BAT refined analysis
- GRB 100802A: Liverpool Telescope observations
- GRB 100802A: ROTSE-III Optical Limits
- GRB 100802A: Possible Swift/UVOT Detection of Optical Afterglow
- GRB 100802A: Swift detection of a burst
- GRB 100728B - NOT optical observation
- GRB 100728B: Swift/UVOT Observations
- GRB 100728B: Lick Observations
- GRB 100728B: Continued KAIT observations
- GRB 100728B, Swift-BAT refined analysis
- GRB 100728B: Swift-XRT Refined Analysis
- Konus-Wind observation of GRB 100728A
- GRB 100728A: GROND Detection of the NIR Afterglow Candidate