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"2747 results found.
- GRB 990510 optical observations
- Refined IPN error box for GRB990506
- GRB 990506: Limits on the possible optical transient
- GRB 990506, armchair astronomy
- GRB 970228: Redshift and properties of the host galaxy
- GRB981220 VLBA observations
- GRB990321 REFINED IPN ANNULUS
- GRB990321 IPN TRIANGULATION
- GRB 990316 Optical Observations
- GRB990316: simultaneous optical observation
- ASM/IPN error box for GRB 990308 (BATSE #7457)
- GRB990308, Possible new SGR~0209+70
- GRB981220, IPN localization
- GRB 981220, radio observations
- GRB 990123: Updated Keck Spectroscopy Results
- GRB990123, Optical observation
- GRB 990123: New Constraints on Possible Foreground Galaxies
- Search for Potential Images of GRB 990123
- Search for Potential Images of GRB 990123
- GRB990123 IPN annulus
- GRB 990123 : Multiple and Distorted Images of the Host Galaxy?
- GRB 990123 Spectroscopic Redshifts
- GRB 990123: Possible Gravitationally Lensed Burst?
- GRB 990123 optical observations
- GRB 990123: Bright New Source, Possible Optical Transient
- Possible identification of SN1999E with GRB980910
- GRB981220
- GRB 981226 optical observations
- GRB 981220
- GRB980703: Radio transient
- SGR1627-41, Refined IPN annulus location
- Reduced error box of SGR 1627-41
- SGR 1627-41
- SGR1900+14
- SGR1900+14
- GRB980519 optical observations
- GRB980519 Optical Observations
- GRB 980425 Brightness Temperature
- GRB980329 infrared observations
- Optical Observations of the GRB 971227 field
- GRB971227: Plaskett R-band observations
- GRB 971227: Optical clarifications
- GRB 971214: Redshift from Keck Optical Observations
- GRB 971214: USNOFS Observations Summary
- IRAS 18119-1342 and the possible new SGR
- Possible new SGR from US Naval Observatory
- GRB 970828: Palomar Observations