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').
18287 results found.
- GRB 051111: Swift-BAT refined analysis
- GRB 051109A Optical Observations
- GRB051111a: SARA Observations
- GRB 051111A: KAIT optical observations
- GRB051111: Super-LOTIS Early Detection
- GRB 051111: ROTSE-III Analysis of Prompt Counterpart
- Faulkes Telescope R-band detection of GRB051111
- GRB051111: Swift-BAT detection of a bright burst
- GRB 051111A: ROTSE-III Detection of Possible Counterpart
- Early RAPTOR measurements of GRB 051109a - the movie.
- Konus-Wind observation of GRB 051109A
- GRB 051109B: Swift-BAT refined analysis
- GRB 051109B: ROTSE-III Optical Limits
- GRB 051109A: Swift-UVOT Observations
- IPN triangulation and Konus spectrum of the short/soft GRB051107 (large
- GRB051109B: no UVOT source detected
- GRB051109B: XRT refined analysis
- GRB 051109B : Lulin Optical Observations
- GRB051109A: further steepening in the X-ray light curve
- GRB051109A: XRT refined analysis
- GRB051109B: XRT position
- GRB 051109B: Super-LOTIS Observations
- GRB 051109B Kiso optical follow-up observation
- GRB 051109B: Swift detection of a burst
- GRB051109: Early Super-LOTIS Detection
- GRB 051109: Swift-BAT refined analysis
- GRB 051109a: MDM Observations
- GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
- GRB051109: Swift detection of a burst
- GRB 051109a: IR Detections
- GRB 051109: ROTSE-III Detection of Possible Counterpart
- GRB051105B: Swift/XRT upper limit
- GRB051105B: Swift/UVOT upper limit
- GRB051028: Swift-XRT refined analysis
- GRB 051105a: MDM Observations
- GRB051105A: Swift/UVOT Observations
- IPN triangulation and Konus spectrum of the bright short/hard GRB051103
- XRT observations of GRB 051105A
- GRB 051105: Swift-BAT improved refined analysis
- GRB 051105: Swift-BAT refined analysis
- GRB 051105: Swift detection of a short burst
- GRB051028: Swift/UVOT upper limits
- GRB051028: Swift XRT Position
- GRB 051022: XRT Refined Spectral and Temporal Analysis--Correction
- GRB051022: Swift XRT measurement of jet break
- GRB051021B: Swift/UVOT Upper limits
- GRB 051022: XRT Refined Spectral and Temporal Analysis
- GRB051012: Swift-XRT analysis
- GRB051021B: Swift XRT refined analysis
- GRB 051022: WSRT Radio Detection
- GRB 051022: Swift/UVOT Upper Limits
- GRB051021A: Swift XRT refined analysis
- GRB051022: Optical Observations
- GRB 051022, J & K-band observation
- GRB051022: Swift XRT Position
- GRB051021: Swift/UVOT Upper Limits
- GRB 051021B: Refined analysis of the Swift-BAT burst
- GRB051021B: Swift XRT Position
- GRB 051021B: Swift detection of a burst
- GRB051021: Swift XRT analysis
- GRB051021.63
- Swift-BAT trigger 160640 is not a real GRB
- Swift-BAT trigger 160619 is not a GRB
- Swift-BAT triggered on a posible CR Shower or possible GRB
- GRB 051016A: Swift/UVOT upper limits
- GRB 051016B: refined analysis of the Swift/XRT data
- GRB 051016B: Swift/UVOT detection
- GRB 051016B : Optical follow-up at Lulin
- GRB 051016B: Refined analysis of the Swift-BAT burst
- GRB 051016B: Swift detection of a soft burst
- GRB 051016: Swift-BAT refined analysis
- GRB051016 XMM-Newton observation
- GRB051016: Swift XRT refined analysis.
- GRB051016: Swift detection of a burst
- Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
- GRB 051012: Swift-BAT detection of burst yesterday
- Swift trigger 159578 is not a burst
- Swift-BAT Trigger 159578 is a possible burst
- GRB050805A: Rc optical observations
- GRB 051006: Swift/UVOT Upper Limits
- GRB 051008 - a low redshift low-luminosity burst?
- GRB051008: Swift XRT refined analysis
- GRB051008 - Swift UVOT upper limits
- Konus-Wind observation of GRB 051008
- GRB051008: Final refined analysis of the Swift-BAT burst
- GRB 051008: R-band upper limit
- GRB051008: Refined analysis of the Swift-BAT burst
- GRB 051008: Swift XRT position
- GRB 051008: early Swift XRT analysis
- GRB 051008: Swift UVOT Candidate
- GRB051008: Swift-BAT detection of a bright burst
- GRB 051006: XRT refined analysis
- Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
- GRB 051006: optical observations at Sierra Nevada
- GRB051006: Refined analysis of the Swift-BAT burst
- GRB 051006: XRT position
- GRB051006: Swift detection of a burst
- Swift-BAT triggers 158261 and 158262 Retraction
- GRB051001: Swift UVOT Upper Limits
- GRB 050925: Second Epoch WSRT Radio Observations