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"11468 results found.
- GRB990806: BATSE Observations
- GRB 990705, R-band observations
- Infrared and Optical Observations of GRB990705
- GRB990704
- Refined BeppoSAX-WFC position of GRB990704
- GRB990704: BeppoSAX detection
- IPN error box for GRB990527
- Late Afterglows of GRBs 990510, 990123
- X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
- X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
- optical observation of the X-ray/GRB transient SAX J0835.9+5118
- BeppoSAX: A new fast X-ray transient
- VLT spectrum of GRB990510
- GRB 990510: BATSE Observations
- GRB990510
- GRB 990506: BATSE Observations
- GRB 990506, optical observations
- GRB990506 Optical observations
- New IPN/RXTE error box for GRB990506
- GRB 970228: Redshift and properties of the host galaxy
- GRB980425 Optical observations of exponential decline at late time
- GRB990323 PRECISE IPN POSITION
- GRB990321 IPN TRIANGULATION
- GRB990308, Possible new SGR~0209+70
- GRB 981220, radio observations
- BATSE Flight Anomaly
- Optical Observations of GRB990217
- GRB 990123: Continued Radio Observations
- Search for Potential Images of GRB 990123
- "GRB 990123: New BV Observations"
- GRB 990123: BATSE Observations
- GRB990123 Optical Observation
- GRB990123, BeppoSAX-NFI X-ray afterglow detection
- GRB 980613: Spectroscopy of the host galaxy
- GRB 981226 optical observations
- GRB981226, BeppoSAX-NFI follow-up
- GRB 981220: BeppoSAX/GRBM results
- GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
- GRB 980923 BATSE Observations
- GRB980703 optical photometry
- GRB 980703: BATSE Observations
- GRB980703: LOTIS observation at early times
- GRB980519 observation report
- GRB980703 optical followup
- Radio observations of SGRs
- GRB 980613: BATSE Observations
- Discovery of a new SGR source, SGR1627-41
- SGR1900+14
- SGR1900+14
- BATSE on-board GRB trigger change
- GRB 980519 Optical Observations
- GRB980519 BATSE Observations
- GRB970519, optical follow-up at Schmidt Calern
- GRB980519 optical observations
- GRB 980519 Optical Observations
- GRB980519, BeppoSAX-WFC updated position
- GRB980519, BeppoSAX-WFC position
- GRB 980425 Radio Light Curve
- GRB980425 BATSE observations
- GRB 980329 ROSAT observation
- GRB980329 optical observations
- GRB980329 optical observations
- GRB980329 optical observations
- GRB 971227: Optical Observations
- GRB971227: LOTIS observations
- GRB 971214: EUVE Observations
- GRB 971024: USNO Observations
- Possible new SGR from US Naval Observatory