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"21458 results found.
- Swift-BAT trigger 306829 is IGR J16479-4514
- GRB 080319B: RAPTOR observations of a naked eye burst
- GRB 080319A: Swift-XRT Team Refined Analysis
- GRB 080319B, Swift-BAT refined analysis
- GRB 080319C: Swift-XRT Team Refined Analysis
- GRB 080319B: Swift-XRT Team Refined Analysis
- GRB 080319D: Swift/UVOT Refined Analysis of the Fading Optical Afterglow Candidate
- GRB 080319C: AGILE-MCAL observation of the prompt emission
- GRB 080319D: MASTER-VWF-Kislovodsk optical observation
- GRB 080319C: MASTER-VWF-Kislovodsk optical observation
- GRB 080319D: Swift detection of a burst with a possible optical afterglow
- GRB 080319B: TORTORA synchronous observation
- GRB 080319A/B/C: INTEGRAL SPI-ACS light curves available
- GRB 080319B: Enhanced Swift-XRT position
- GRB 080319A: Enhanced Swift-XRT position
- GRB 080319A, Swift-BAT refined analysis
- GRB 080319C: Early Super-LOTIS Observations
- GRB 080319C: Swift detection of a burst with an optical afterglow
- GRB 080319C: KAIT OA candidate
- GRB 080319b prompt optical observation by Pi-of-the-Sky
- GRB 080319B: Gemini-South Spectroscopy
- GRB080319B Liverpool Telescope optical afterglow candidate
- GRB 080319B: Super-LOTIS Detection of a Bright OT
- GRB 080319B: KAIT OA
- GRB080319A: P60 Optical Afterglow Observations
- GRB 080319B: UVOT Position
- GRB 080319B: Swift detection of an intense burst with a bright optical counterpart
- GRB 080319A: Swift detection of a burst
- Swift Trigger 306745 is not a GRB
- Swift Trigger 306616 is not a GRB
- GRB080315: Bok Optical Observations
- Swift/UVOT observations of GRB 080315
- Swift trigger 306323: Swift-BAT/XRT refined analysis
- SAX J1818.6-1703: Swift detection (trigger 306379)
- GRB 080315: TAROT Calern observatory optical observations
- GRB 080315: Swift detection of a possible burst
- GRB 080310: ROTSE-III Observations of Optical Counterpart
- GRB080310: Optical observation by MITSuME telescope
- GRB 080229A: GAO 150cm telescope Optical Observation
- GRB 080307: NIR upper limit
- GRB 080229: NIR upper limit
- GRB 080310, Swift-BAT refined analysis
- GRB080307: optical upper limit
- GRB 080310: Swift-XRT refined analysis
- GRB 080310: Swift/UVOT Refined Analysis
- GRB 080310 - SDSS Pre-Burst Observations
- GRB 080310: Enhanced Swift-XRT position
- GRB 080310: VLT/UVES spectroscopy
- GRB080310: Super-LOTIS suggestion of brightening
- GRB 080310: Swift detection of a burst with optical afterglow
- GRB080229, optical upper limit (Correction)
- GRB080307, optical upper limit
- GRB080307 BOAO optical afterglow observation - detection of a possible OT
- GRB080229, optical upper limit
- GRB 080307: Swift-XRT Team refined analysis
- GRB 080307: Swift/UVOT Upper Limits
- GRB 080307: Early RAPTOR Limits
- GRB 080307, Swift-BAT refined analysis
- GRB080307 - SDSS Pre-Burst Observations
- GRB080307: Optical upper limits
- GRB 080307: Gemini-N i-band observations - candidate afterglow
- GRB 080307: BOAO imaging - retraction and new limit
- GRB 080307: retraction of UVOT candidate
- GRB 080307: Enhanced Swift-XRT position
- GRB 080307, Preliminary Swift-BAT refined analysis
- GRB 080307: Swift detection of a burst
- VLA possible radio detection of GRB 080229
- GRB 080303: Swift/UVOT follow-up of afterglow detection
- GRB 080303, Swift-BAT refined analysis
- GRB080303: Swift XRT refined analysis
- GRB 080303: Enhanced Swift-XRT position
- Swift UVOT observations of GRB080229B
- GRB080229B: Swift XRT afterglow observation
- GRB 080303A: Faulkes Telescope South optical afterglow observations
- GRB 080303
- GRB 080303: Swift detection of a burst with optical afterglow
- GRB 080303: REM NIR afterglow candidate
- GRB 080303A: ROTSE-III Optical Limits
- GRB 080229: I-band observations from OSN
- GRB 080229: VLT NIR observations
- GRB080229: Swift XRT refined analysis
- GRB 080229: TNG NIR observations
- GRB 080229: Deep Gemini/GMOS optical observations
- GRB 080229: Enhanced Swift-XRT position
- GRB 080229: REM NIR observations
- GRB080229: Possible optical afterglow
- UVOT analysis for GRB080229
- GRB 080229, Swift-BAT refined analysis
- GRB 080229: Faulkes Telescope South optical limit
- GRB 080229A: ROTSE-III Optical Limits
- GRB 080229: Swift detection of a bright burst
- GRB080207: optical observations
- GRB080211: optical observations
- Swift-XRT improved positions, and new redshift limits.
- ESO optical and NIR observations of GRB 080218B
- GRB 080204: Suzaku WAM observation of the prompt emission
- GRB 080218B, Swift-BAT refined analysis
- GRB 080218B: Swift-XRT refined analysis
- Swift/UVOT observations of GRB080218B
- GRB 080218B: REM NIR early upper limits