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.
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"
- GRB 080319B: Potential Jet Break Observed by Swift-XRT and UVOT
- GRB 080405: Swift-BAT refined analysis
- GRB 080405: Swift-XRT position
- GRB 080405: Mars Oddysey and Swift-BAT detection, possible host galaxy
- GRB 080325: optical upper limit
- GRB 080328: GAO 150cm telescope Optical Observation
- GRB080330: Improved Swift XRT Position
- GRB 080330: Prompt PROMPT Observations
- GRB080330: optical observations
- GRB 080319B: TORTORA light curve (Correction)
- GRB080328, RIMOTS optical upper limit
- GRB080330: optical observations
- GRB080330: Swift XRT refined analysis
- GRB 080330: REM optical observations
- GRB 080330, SMARTS optical/IR afterglow observations
- GRB 080330 Swift-UVOT refined analysis
- GRB 080328: Suzaku WAM observation of the prompt emission
- GRB080330: TNT optical observations
- GRB 080330, Swift-BAT refined analysis
- Konus-Wind observation of GRB 080328
- GRB 080330: Redshift Confirmation from Hobby-Eberly Telescope Spectroscopy
- GRB080330: LOAO R-band Detection
- GRB 080330: GROND Observations
- GRB 080330: NOT redshift
- GRB 080330: TAROT Calern observatory optical observations
- GRB 080330A: PAIRITEL Infrared Detections
- GRB 080330: error in reported XRT position
- GRB080330 - SDSS Pre-Burst Observations
- GRB 080330: Liverpool Telescope Optical observations
- GRB 080330A: ROTSE-III Detection of Optical Counterpart
- GRB 080330: Swift detection of a burst with an optical counterpart
- GRB 080330: TAROT Calern observatory optical detection
- GRB 080319B: Continued Gemini-South followup and possible host galaxy
- GRB 080328: BTA optical imaging and spectroscopy
- GRB 080328, Swift-BAT refined analysis
- GRB 080328: Swift XRT refined analysis
- GRB 080325, Swift-BAT refined analysis
- Swift/UVOT observations of GRB080328
- GRB080325 - I and z-band Imaging
- GRB080319B, BVRcIc field calibration
- GRB 080328: Enhanced Swift-XRT position
- GRB080328: Faulkes Telescope North observations
- GRB 080328: Swift detection of a burst with an optical counterpart
- GRB 080325: Subaru detection of NIR afterglow candidate
- GRB080310, late-time photometry with LBT
- GRB 080325: MITSuME Akeno optical upper limits
- GRB080325: XRT Refined Analysis
- GRB 080325: GROND Observations
- GRB080319B: optical observations
- GRB 080325: Swift/UVOT Upper Limits
- GRB 080319C: Gemini-North spectroscopic redshift
- GRB 080325: Early observations from OSN
- GRB 080325: NIR afterglow candidate
- GRB 080319D: GROND Detection of the Optical Counterpart
- GRB 080325: Enhanced Swift-XRT position
- GRB 080325: Swift detection of a burst
- GRB 080319B : Apparent spectral evolution in very early Swift/XRT WT mode data: intrinsic or pile-up effect?
- IBAS Alert n. 5245: NOT a GRB
- GRB 080319B: Spitzer Mid-infrared Observations
- GRB 080319C: Suzaku WAM observation of the prompt emission
- GRB 080319B: Second & Third Epoch WSRT Radio Observations
- Radio Detection of GRB 080319B
- GRB 080320, Swift-BAT refined analysis
- GRB 080319B: Optical observation (Brno, CZ)
- GRB 080319D: GROND Observations
- GRB 080319B: TORTORA light curve
- GRB 080319B: optical upper limit
- GRB 080319D: optical upper limit
- GRB080319B: Time-Independent XRT Spectrum
- GRB 080319D, Swift-BAT refined analysis
- GRB 080319C: UVOT Observations
- GRB 080319B: UVOT Observations
- GRB 080319A: UVOT Observations
- GRB 080320: Swift XRT refined analysis
- GRB 080319B - CARMA mm Observations
- GRB 080320: Early Super-LOTIS Observations
- GRB 080320: J detection with FLAMINGOS
- GRB 080319D: Swift XRT refined analysis
- GRB 080320: optical limit
- GRB 080320: Gemini-N optical afterglow
- Konus-Wind observation of GRB 080319C
- GRB 080319B: Gemini-South photometry
- GRB 080319B: Allen Telescope Array Observations
- GRB 080319B optical observations
- GRB 080319C, Swift-BAT refined analysis
- Konus-Wind observation of GRB 080319B
- GRB 080319B: WSRT Radio Observations
- GRB 080320: SDSS source and Gemini-N observations
- GRB 080320: Enhanced Swift-XRT position
- GRB 080320: optical limit from IAC80
- GRB 080319C: Early RAPTOR Observations
- GRB 080319B: second epoch imaging from Canarias (correction to GCN7469)
- GRB 080319C: KAIT OA observations
- GRB 080320 - SDSS Pre-Burst Observations
- GRB 080320: Swift detection of a burst
- GRB 080320: ROTSE-III Optical Limits
- GRB 080319B : Lulin observation of temporal break at 0.2 days
- GRB 080319B: ROTSE-III Observations of Optical Counterpart
- GRB 080319B: optical observations
- GRB 080319C - SDSS Pre-Burst Observations