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"44408 results found.
- GRB 070510: Swift detection of a possible burst
- GRB070509: Swift-XRT Refined Analysis
- RHESSI Spectrum of GRB070508
- GRB 070508: OA fading and tentative redshift
- GRB 070509, Swift-BAT refined analysis
- GRB 070508: Suzaku/WAM observation of the prompt emission
- GRB 070509: REM observations
- GRB 070509: Swift detection of a burst
- GRB 070509: ROTSE-III Optical Limits
- GRB070508: Swift/UVOT Observations
- GRB 070508, SMARTS optical afterglow observation
- GRB 070508, Swift-BAT refined analysis
- GRB 070508: Multicolor optical observations and possible redshift limit
- GRB 070508: Swift-XRT refined analysis
- GRB 070508: Optical observation limiting magnitude
- GRB 070508: Optical afterglow detection
- GRB 070508: REM observations
- GRB 070508: TAROT La Silla observatory optical observations
- GRB 070508: Swift detection of an intense burst with an optical counterpart
- GRB070412: MAGIC telescope GeV observation
- Swift-BAT trigger 278809 is not a GRB
- GRB 070507: Swift detection of a possible cosmic ray shower event or a possible burst
- GRB 070506: VLT redshift
- GRB070506: Swift/UVOT Observations
- GRB070506: Swift XRT refined analysis
- GRB 070506, Swift-BAT Refined Analysis
- GRB 070506: Swift detection of a burst with optical afterglow
- GRB 070412, deep LBT imaging
- GRB 070429A: Swift XRT further analysis
- GRB070429B: VLT observations
- GRB 070429A: optical observations
- GRB070429B: position correction
- GRB 070309: Swift-XRT afterglow confirmation
- GRB070429B: possible host galaxy detection
- VLA observation of GRB 070429B
- Swift/UVOT observations of GRB070429B
- GRB 070429B, Swift-BAT refined analysis
- Swift/UVOT observations of GRB070429A
- GRB 070429A: Swift XRT refined analysis
- GRB 070429A, Swift-BAT refined analysis
- GRB 070429A: optical and NIR observations
- GRB 070429B: Swift XRT refined analysis
- GRB 070429B: ROTSE-III Optical Limits
- GRB 070429B: Swift detection of a short burst
- GRB 070429: ROTSE-III Optical Limits
- GRB 070429: Swift detection of a burst
- GRB 070427, Swift-BAT Refined Analysis
- LT monitoring of GRB070412
- GRB 070427: Swift detection of a burst
- GRB 070411, further deep LBT photometry
- GRB 070411: Late-time Keck imaging
- GRB 070411 : Planned XMM-Newton observation
- GRB070419B: Suzaku WAM observation of the prompt emission
- GRB 070420, SMARTS optical/IR afterglow observations
- GRB 070411, deep LBT photometry
- GRB 070420: pseudo-z~1.56 from spectral parameters of the prompt
- Konus-Wind observation of GRB 070420
- GRB 070411: break in the optical light curve
- GRB 070420 Swift-BAT Refined Analysis
- GRB070419A: Kuiper Optical detection
- GRB070419a: Swift UVOT observations
- GRB 070419A: MARGE Observations
- GRB 070420: optical rebrightening observed at Mt. John
- GRB 070420: Swift XRT refined analysis
- GRB070420: Swift UVOT continuing observations
- GRB 070411: BART early limit
- GRB 070420: Faulkes Telescope South Observations
- GBR 070419A: Swift/XRT refined analysis
- GRB 070420: TAROT La Silla observatory optical observations
- GRB 070420: NIR and optical afterglow confirmed
- GRB 070420: Swift detection of a burst with optical afterglow
- GRB 070419A: MITSuME Okayama Observations
- GRB 070419A: Early Super-LOTIS Observations
- GRB 070419B, Swift-BAT refined analysis
- GRB 070419A Swift-BAT Refined Analysis
- GRB070419B: Confirmation of Optical Transient
- GRB 070419A: RAPTOR Detection of Early Emission
- GRB 070419B: Swift XRT refined analysis
- GRB 070419: Keck/LRIS Absorption Redshift
- GRB 070419B: optical afterglow confirmation
- GRB 070419A, Optical observations
- GRB 070411: Deep VLT detection
- GRB070419 - SDSS Pre-Burst Observations
- GRB 070419A: SARA observations
- GRB 070419A: NAYUTA Optical Observation
- GRB 070419A: Faulkes Telescope North Optical Observations
- GRB 070419B optical afterglow candidate
- GRB 070419A: Optical and IR observations with KANATA
- GRB 070419B: optical afterglow candidate
- GRB 070419A: Lulin Optical observation
- GRB070419A, optical observation
- Infrared detection of GRB070419A with UKIRT
- GRB 070419A: Kiso Optical observation
- GRB070330: Correction to UVOT position
- GRB 070419: P60 Confirmation of Optical Afterglow
- GRB 070419B: Swift detection of a burst
- GRB 070419A: ROTSE-III Optical Limits
- GRB 070419: Swift detection of a burst
- Swift-BAT Trigger 276045 is a Cosmic Ray Shower event
- GRB 070418: Optical and IR observations with KANATA