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').
23953 results found.
- GRB 991216 Optical Observations
- GRB 991216, optical observations
- GRB 991208 SAO-RAS Spectroscopy
- SAX J2303.2+0015: an x-ray/GRB?
- GRB 991216, Optical Transient
- GRB991216 ('Beethoven Burst') B, R, and K Observations
- GRB991216, infrared observations
- GRB 991208 optical observations
- GRB 991216 Optical Observation
- GRB 991216: Extremely bright BATSE burst
- R-band Observations of GRB991208 at TNG
- GRB991208, optical observations
- GRB 991208, Optical Observation
- GRB991208, optical observations
- GRB 991208 optical observations
- Optical Observations of GRB991105
- GRB991106: BeppoSAX/BATSE results
- GRB991106, near-infrared observations
- BeppoSAX NFI Observation of GRB991106
- GRB 991106, radio observations
- GRB991106: the first BeppoSAX short GRB detection?
- GRB 991105: BATSE Observations
- GRB 991106 Optical Observations
- GRB991106, optical observation at SAO-RAS
- GRB 991106, LOTIS Optical Observations
- GRB991105: SAX-GRBM/-WFC detection
- GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
- GRB 991014, Optical Observations
- GRB 991014 - BeppoSAX NFI observations
- GRB 991014, radio observations
- GRB 991014, Optical Observations
- GRB 991014, optical observations
- GRB 990915 optical observations
- Optical Observations of GRB990907
- GRB990907: BeppoSAX follow up and X-ray afterglow
- GRB990907 and 990908
- GRB 990712 Late Optical Decay and Host Galaxy
- GRB990806 BeppoSAX follow up
- GRB990806: BATSE Observations
- GRB 990806 Optical observations
- GRB 990806, Optical Observations
- GRB 990806, optical observations
- GRB 990806, Optical Observations
- GRB990806 UBVRIJHK observations
- GRB 990712 Optical Observations
- GRB 990712
- Late-time HST/STIS Observations of GRB 990510
- BeppoSAX NFI Observation of GRB990705
- BeppoSAX NFI Observation of GRB990705
- GRB 990705, R-band observations
- Infrared and Optical Observations of GRB990705
- GRB990704: SAX-NFI results summary
- GRB990704 radio and optical observations
- GRB990704
- GRB990704, optical observations
- BeppoSAX NFI Observation of GRB990627 X-ray afterglow
- Optical Observations of GRB990627
- BeppoSAX: GRB990625
- Late-time HST/STIS Observation of GRB 990123
- Optical Observations of GRB 990506
- GRB990527 Optical Observations
- X-ray/GRB 1SAX J0835.9+5118, Optical Observation
- 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
- X-ray/GRB 1SAX J0835.9+5118, Optical Observations
- X-ray/GRB 1SAX J0835.9+5118, Optical Observation
- X-ray/GRB 1SAX J0835.9+5118, Optical Observation
- X-ray/GRB 1SAX J0835.9+5118, Optical Observation
- radio observations of X-ray/GRB transient field
- optical observation of the X-ray/GRB transient SAX J0835.9+5118
- Optical report on X-ray/GRB transient
- radio detection of X-ray/GRB transient
- BeppoSAX: A new fast X-ray transient
- GRB 990510: optical observations
- GRB 990510: optical linear polarization
- GRB 990510: optical observations
- GRB990510: X-ray afterglow
- GRB 990510: Broad Band Break
- GRB 990510: BATSE Observations
- GRB 990510: BeppoSAX/GRBM observations
- GRB990510 optical observations
- GRB 990510 optical observations
- GRB 990506 Radio Observations
- GRB 990123, optical monitoring
- GRB 990506: BATSE Observations
- GRB 990506, optical observations
- GRB 990506, Optical Observations
- GRB 990506 optical observations
- GRB 990506, optical observations
- GRB 990506, armchair astronomy
- GRB 990506, optical observations from +1 to +3 hours
- GRB 990506, optical observations
- GRB990506 observation plan
- IPN localization for GRB990506
- GRB990323 PRECISE IPN POSITION
- GRB 990316 Optical Observations
- GRB 990316 optical observations
- GRB990316: simultaneous optical observation
- GRB990316 - Optical null results