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"21392 results found.
- GRB060204a: Swift XRT Detection of an Afterglow Candidate
- GRB060206 - Swift UVOT Confirmation of Optical Afterglow
- GRB060206: Swift-BAT detection of a burst
- GRB 060204C: XRT analysis of Swift J061223.0+701243.9
- BAT GRB 060204C is probably not a GRB
- GRB 060204B: BVRi-band detections of optical afterglow
- GRB 060204A: Swift XRT upper limit
- GRB060204B: Swift/UVOT refined analysis
- GRB 060204C: optical observations
- Swift XRT Observation of GRB 060204C
- GRB 060204B: Swift-BAT refined analysis
- GRB060204B: Swift XRT Team Refined Analysis
- GRB 060204C: OSN limits
- GRB 060204C: Liverpool Telescopes optical limit
- GRB 060204C: ROTSE-III Optical Limits
- GRB 060204C: Swift-BAT detection of a burst
- GRB 060124: Radio Observations
- GRB060204B: Faulkes OT candidate
- GRB 060204B: ART optical limit
- GRB060204B, optical observation
- GRB060204B - SDSS pre-burst observations
- GRB 060203: Swift-BAT refined analysis
- GRB 060204B: Swift detection of a burst
- GRB 060203: RTT150 optical observations
- GRB060203: Swift XRT Team Refined Analysis
- GRB060203 - Swift UVOT observation
- Swift-BAT trigger is GRB 060203
- GRB 060203: IR Counterpart
- GRB060203: Observations with SARA
- GRB 060203: P60 Confirmation of Optical Afterglow
- Possible GRB 060203: candidate optical counterpart
- Swift BAT Trigger 180151: Swift XRT source detection
- Possible GRB 060203: optical observations at Asiago
- Swift-BAT trigger 180151 is unknown origin at this time
- GRB 060202: GETS observation
- GRB 060202: Gemini-N J, H, K_s observations
- GRB 060202: Near-IR Observation with UKIRT/WFCAM
- GRB 060202: Optical Afterglow Candidate from Keck/LRIS
- GRB 060202: Refined analysis of the Swift-BAT burst
- GRB060202, optical observation
- GRB 060202: Swift/UVOT upper limits
- GRB 060202: Swift XRT Team Refined Analysis
- GRB 060202 : Lulin R and I band limit
- GRB060202: Faulkes North observation
- GRB 060202: Swift detection of a burst
- GRB 060121: Gemini Late-time Observations
- GRB 060130: Swift/XRT observation
- GRB 060123: Gemini spectroscopy of the putative host galaxy
- GRB 060123: VLA Radio Observations
- Possible GRB 051221B: MDM Correction
- GRB 060123: Swift refined analysis of an unusual GRB
- GRB060124, BVRcIc field calibration
- GRB060105: refined analysis of the Suzaku observation
- GRB 060121: Probable Detection of NIR Afterglow
- GRB 060124: HETE detection and spectrum of the main peak
- Refined XRT Position for GRB 060123
- Konus-Wind observation of GRB 060124
- GRB060124: detailed XRT analysis
- GRB 060124 Optical Observations
- GRB060123: Optical and IR Imaging
- GRB 060123: P200 Observations
- GRB 060124: XRT refined analysis
- GRB 060124: R band Observations
- GRB 060124: Extremely long burst, Swift-BAT refined analysis
- GRB 060123: Swift detection of a very long, faint burst
- GRB 060124: TAROT optical limits
- GRB 060124: Swift/UVOT Observation
- GRB 060124: Confirmation of the Afterglow
- GRB 060124: XRT position
- GRB 060124: Optical Afterglow Candidate from Tautenburg
- GRB 060124: Optical Observations at Tautenburg
- GRB 060117: Suzaku WAM observation of the prompt emission
- GRB060124:MASTER optical observation
- GRB 060111B: Suzaku WAM observation of the prompt emission
- GRB 060124: Swift-BAT detection of a burst
- GRB 060116: Radio Detection
- GRB 060116: MARGE optical observations
- GRB 060121: Swift/UVOT upper limits
- GRB 060121: Liverpool Telescopes optical limits
- GRB 060121: Swift XRT refined analysis
- GRB 060121: candidate optical counterpart
- GRB 060121: Swift XRT refined position
- GRB060117 - ATCA 3/6cm radio limits
- GRB 060117: pseudo-z from spectral parameters of the prompt emission
- Konus-Wind observation of GRB 060117
- GRB 060117: Refined analysis of the Swift-BAT burst
- GRB 060117: FRAM optical afterglow candidate
- GRB 060117: Swift-BAT detection of a bright burst
- GRB 060116: VLT optical observations
- GRB 060116: Refined analysis of the Swift-BAT burst
- GRB 060116: XRT refined analysis
- GRB 060116: IR Candidate Afterglow
- GRB 060116: Swift/UVOT upper limits
- GRB060115: REM observations
- GRB 060110: XRT position and analysis
- GRB 060116 : Lulin optical limit
- GRB 060116: ROTSE-III Optical Limits
- GRB060116: XRT position
- GRB060116: Faulkes North observation
- GRB 060116: Swift-BAT detection of a burst