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').
- GRB 050412: LCO Optical Observations
- GRB 050412: Optical observations
- GRB050412: P60 Observations
- GRB 050412: Swift XRT Position
- GRB050412: optical limit before and during GRB
- GRB 050412: LCO optical observations
- GRB050412: ROTSE-III Optical Limits
- Swift-BAT Detection of GRB 050412: A Bright, Long Burst
- GRB 050412: IR and Optical observations
- GRB 050412: IR Observations
- GRB050408: Radio Observations
- GRB 050401: Optical limit
- GRB 050408: Optical limit
- GRB050410: P60 Observations
- GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
- GRB 050410, optical observations
- GRB 050408: PROMPT VRcIc Observations
- GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
- GRB 050410 R band Optical Observations
- GRB050410 : Null detection report
- GRB 050410, optical observations
- GRB050410: Radio Observations
- GRB 050408: Swift XRT measurement of possible jet break
- GRB050410: MASTER optical observations
- GRB 050410: Early observations with Swift-UVOT
- Swift-BAT detection of GRB 050410
- GRB 050410: Swift XRT Position
- GRB 050408: Retraction of Proposed Host Galaxy
- GRB 050408: Inconsistency of host galaxy identification
- GRB 050408: Subaru Observations
- GRB 050408: WIDGET simultaneous optical observations
- GRB 050408: SOAR UBVRc Observations
- GRB 050408: Properties of the Host Galaxy
- GRB 050408: Mercator Optical Observations
- GRB050408: Radio Observations
- GRB 050408: Swift XRT analysis
- GRB 050408, SMARTS optical/IR afterglow observations
- GRB 050408: Optical limit at 20 min after the burst
- GRB 050408, optical observations
- GRB050408: REM NIR and Optical observation
- GRB 050408: Moderate-resolution Gemini Spectroscopy
- GRB 050408,optical observation
- GRB 050408 Optical Observations
- GRB 050408: Emission and absorption redshift
- GRB 050408: Mercator Optical Observations
- GRB 050408: Magellan astrometry and photometry
- GRB 050408: First Optical observations with TFOSC at the RTT150
- GRB 050408: steepening of the optical decay
- GRB 050408: Optical afterglow confirmed
- GRB 050408: opitcal observation
- GRB 050408, optical observations
- GRB 050408 optical candidate
- GRB 050408: Swift XRT Position
- GRB 050408: ROTSE-III Optical Limits
- GRB 050408 (=H3711): A Long X-Ray-Rich GRB Detected by HETE
- GRB050408: MASTER optical observations
- GRB050401: Radio Detection
- Swift-UVOT Optical Counterpart Candidate to XRF 050406
- GRB 050406: Magellan optical observations
- GRB 050406: early Swift XRT analysis results
- GRB 050406 BAT refined analysis
- GRB 050406: Early observations with Swift-UVOT
- GRB 050406: Swift XRT Position
- Swift-BAT detection of GRB 050406
- Konus-Wind observation of GRB 050401
- GRB050401: Radio observation at 610 MHz with GMRT
- GRB050401, radio observation at 4.8 GHz and 8.64 GHz
- GRB 050401: VLT spectroscopic redshift
- GRB 050401 Optical Observations
- GRB050401: Maidanak optical observation
- GRB 050401 BAT refined analysis
- Very questionable identity of Swift-BAT GRB050402 (Trig=113225)
- GRB050401: TNG R-band observation
- GRB 050402A: IR Analysis
- GRB050402: XDSS counterpart
- GRB 050402A: IR Observations
- GRB 050402: Early observations with Swift-UVOT
- Swift Trigger 113225: P60 Observations
- GRB050401: ROTSE-III Detection of Prompt Optical Counterpart
- GRB 050401: Optical afterglow confirmed
- GRB 050401: Optical afterglow candidate
- Swift-BAT detection of GRB 050401
- GRB 050401: Prompt XRT position
- Retraction of three Swift GRB triggers
- GRB050331: No Afterglow Detected
- Swift-BAT detection of GRB 050331b
- GRB 050331: Swift UVOT Source
- Swift-BAT detection of GRB 050331
- GRB 050331: Swift XRT Position
- Swift Data Publicly Available Starting April 5, 2005
- GRB050319: radio observation
- Konus-Wind observation of GRB 050326
- GRB050326: optical limit
- GRB 050326: Early observations with Swift-UVOT
- GRB 050326 XMM-Newton observation
- GRB 050326 : Planned XMM-Newton observation
- GRB 050326: Swift XRT Position
- GRB050326: optical limit 33min before GRB
- GRB 050326 BAT refined analysis
- GRB050326: delayed XRT observation