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"
32796 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
- GRB 991216, Optical Afterglow
- GRB 991216: Comparison with DPOSS images
- GRB 991208 optical observations
- Lowell/Perkins observation of GRB 991216
- GRB 991216 Optical Observation
- GRB 991208 Keck Spectroscopy
- GRB 991216: Extremely bright BATSE burst
- GRB991208, optical observations
- GRB 991208 Keck Spectroscopy
- GRB991208 - millimeter detection
- GRB 991208, Optical Observation
- GRB 991208 - OVRO detection
- GRB 991208 Optical Decay
- GRB 991208 optical observations
- GRB 991208 optical observations
- GRB 991208: Radio Observations
- IPN localization of GRB991208
- Optical Observations of GRB991105
- GRB991106: BeppoSAX/BATSE results
- GRB 991106, optical observations
- GRB991106, near-infrared observations
- BeppoSAX NFI Observation of GRB991106
- GRB 991106, radio observations
- GRB991106: the first BeppoSAX short GRB detection?
- GRB 991105: BATSE Observations
- IPN localization of GRB991105
- GRB 991106 Optical Observations
- GRB 991105, optical observations
- GRB991106, optical observation at SAO-RAS
- GRB 991106, LOTIS Optical Observations
- GRB 991106, optical observations
- BeppoSAX GRB Alert: GRB991106
- BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
- GRB ALERT: GRB991105
- GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
- GRB 991014, Optical Observations
- GRB 991014 - BeppoSAX NFI observations
- GRB 991014, Optical Observations
- GRB 991014, radio observations
- GRB991014 BATSE Observations
- GRB 991014, Optical Observations
- GRB 991014, optical observations
- Super-LOTIS optical observation of GRB991014
- IPN/NFI error box for GRB991014
- IPN localization of GRB991014 - CORRECTION
- IPN localization of GRB991014
- BeppoSAX ALERT: GRB991014
- GRB 990915 optical observations
- GRB 990907 optical observations
- BATSE GRB trigger criteria
- Optical Observations of GRB990907
- IPN error box for GRB990915 (=BATSE 7766)
- IPN localization of BATSE #7766 (GRB990915)
- IPN localization of GRB990907
- GRB990908, another BeppoSAX-GRBM/WFC burst detection
- BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
- GRB 990712 Late Optical Decay and Host Galaxy
- GRB 990712, Optical Observation
- GRB990806: BATSE Observations
- GRB 990806 Optical observations
- Optical Observations of GRB990806
- GRB 990806, Optical Observations
- GRB 990806, optical observations
- GRB 990806, Optical Observations
- GRB990806 UBVRIJHK observations
- BeppoSAX ALERT GRB990806: Summer GRB
- GRB 990712 Optical Observations
- GRB990705: No Evidence for Neutrino Signal
- GRB 990712 Optical Decay: Indication of Bright Host Galaxy
- VLT spectrum of GRB990712
- GRB 990712
- Late-time HST/STIS Observations of GRB 990510
- Refined BeppoSAX-WFC position of GRB990712
- GRB 990705, R-band observations
- Updated IPN localization of GRB990705
- IPN localization of GRB990704
- IPN localization of GRB990705
- Infrared and Optical Observations of GRB990705
- GRB 990705, radio observations
- GRB990704 radio and optical observations
- GRB 990704 X-ray Observations
- GRB 990704 Optical Observations
- GRB 990704, optical observations
- GRB990704
- GRB990705: Intriguing Positional Coincidences
- GRB990704
- GRB990704, optical observations
- Identification of a possible optical counterpart for GRB990704
- GRB990704
- Refined BeppoSAX-WFC position of GRB990704
- GRB990704: BeppoSAX detection
- Optical Observations of GRB990627
- GRB 990627, radio observations
- GRB990627: BeppoSAX-WFC final location
- BeppoSAX: GRB990625