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"8275 results found.
- GRB 000307 optical observations
- GRB 000313 - optical transient in the BATSE error box
- GRB000301C - B and R photometry
- GRB000301C - R photometry
- GRB 000301c: K' observations
- GRB000301C, optical R-band observations
- GRB000301c - R photometry and nearby faint source confirmation
- GRB 000301c: K' observations
- GRB 000301C: K' Observations
- GRB000301C OT candidate optical observations
- GRB000301C - Host galaxy not detected in R (?)
- GRB000301C optical observations
- GRB 000301c near-IR observations
- GRB000301C, optical observations
- GRB000301C, near-infrared observations (JHK' photometry)
- GRB 000301C: OT confirmed
- GRB000301c optical observations
- GRB000301C, optical observations
- GRB 000301C : Optical Candidate
- GRB000214: X-ray afterglow candidate
- Optical candidate for GRB000210
- GRB 000115 Optical observations
- GRB991216 late optical observation
- GRB 991216: J band spectrophotometry
- GRB 991217 (SAX J2303.2+0015) Optical observations
- SAX J2303.2+0015 Optical observations
- GRB 991208 Keck Spectroscopy
- GRB 991208 optical observations
- GRB 991208: Radio Observations
- GRB991106: BeppoSAX/BATSE results
- BeppoSAX NFI Observation of GRB991106
- GRB 990712 Late Optical Decay and Host Galaxy
- GRB990806: BATSE Observations
- GRB 990506 - clarification to GCN 352
- 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, 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
- optical observation of the X-ray/GRB transient SAX J0835.9+5118
- GRB 990510: optical observations
- GRB 990510: optical observations
- GRB990510, VI observations
- GRB981220 VLBA observations
- GRB 990316, Radio observations
- GRB 990316, Optical observations
- GRB990316, Optical observations
- GRB 990316 optical observations
- GRB 981220, radio observations
- GRB 990123: New Constraints on Possible Foreground Galaxies
- GRB 990123, new radio source
- GRB990123, Optical observation
- GRB990123 Optical Observation
- GRB981220, Correction to GCN 179
- GRB 981226 Optical Observations
- GRB981226 Optical Observations
- GRB 981226 optical observations
- GRB980425 Optical Follow-up
- SGR1900+14, BeppoSAX-GRBM observations
- GRB 980703 H-band Observations
- GRB980703: radio source/optical transient
- Reduced error box of SGR 1627-41
- GRB 980613 optical/IR obs.
- GRB980613 Near Infra-Red Observations
- GRB980519 Optical Observations
- GRB980515, BeppoSAX IAUC to be submitted
- GRB 980425 Radio Light Curve
- GRB 980425 Brightness Temperature
- GRB980425: Radio Observations
- GRB980326 X-ray Observations
- GRB971214: Keck R & I-band Observations
- GRB971214: Optical Observations and Calibrations
- GRB 971214: KPNO Optical Observations