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"14820 results found.
- CONCAM null result on GRB001005
- CONCAM crude optical limits before and after GRB000926
- GRB 990510: Possible detection of a host galaxy
- GRB 000630: Detection of the Optical Afterglow
- GRB000620: BeppoSAX WFC and GRBM detection
- GRB000615, R-band photometry
- GRB980425, HST/STIS observations of the host galaxy
- GRB000604 optical non-detection
- GRB000604, optical observations
- GRB 000418: Detection of the Host Galaxy
- X-ray Afterglow of GRB 000529
- Possible GRB-related phenomenon
- GRB000424, optical observations
- GRB000418, Radio detection
- GRB000418, K'-band photometry
- GRB 000418, Optical Observation
- GRB000424, optical observations
- RE: Budget cuts in BeppoSAX operations: impact on GRB observation
- X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
- GRB 000301C: A Precise Redshift Determination
- GRB 000301C: HST/STIS CCD Imaging of the field
- GRB000301C - Host galaxy not detected in R (?)
- GRB000301C 250 GHz detection
- Correction to GCN 557 (GRB000214: BeppoSAX GRBM and WFC Detection)
- GRB000214: BeppoSAX GRBM and WFC Detection
- Optical observations of the Chandra X-ray source for GRB000210
- GRB000210: possible afterglow detection with BeppoSAX NFI
- GRB000210: BeppoSAX GRBM and WFC Detection
- GRB 000131 Optical Observations
- GRB000126, optical observations
- Second RXTE Observation of GRB 000115
- GRB 991216 VLBA Observations
- GRB 991216: Detection of the Host and/or Absorber Galaxy
- GRB 991216 RXTE ASM Observations
- GRB 991216 Optical spectroscopy/imaging
- GRB 991208 Infrared Detection
- GRB 991216--Summary of RXTE Observations
- GRB991216 Optical Observations
- GRB991208 - millimeter detection
- GRB 991208 - OVRO detection
- GRB 991208 optical observations
- GRB991106: BeppoSAX/BATSE results
- GRB 991106, optical observations
- GRB991106: the first BeppoSAX short GRB detection?
- GRB991105: SAX-GRBM/-WFC detection
- GRB 990915 optical observations
- GRB990908, another BeppoSAX-GRBM/WFC burst detection
- GRB 990806 Optical observations
- BeppoSAX NFI Observation of GRB990705
- BeppoSAX NFI Observation of GRB990705
- Updated Astrometry for the IR Counterpart of GRB990705
- Infrared and Optical Observations of GRB990705
- GRB990704, optical observations
- GRB990704: BeppoSAX detection
- GRB 990506 - clarification to GCN 352
- GRB 990506 Radio Transient
- X-ray/GRB 1SAX J0835.9+5118, Optical Observations
- X-ray/GRB 1SAX J0835.9+5118, Optical Observation
- radio detection of X-ray/GRB transient
- GRB 990506 R band observations
- GRB 990506: BATSE Observations
- GRB 990506, optical observations
- GRB 990506, optical observations from +1 to +3 hours
- GRB990321 IPN TRIANGULATION
- GRB 990316 Optical Observations
- ASM/IPN error box for GRB 990308 (BATSE #7457)
- GRB 990123: Discovery of the Probable Host Galaxy
- GRB19990123 observations
- GRB 990123 NOT Spectrum Update
- GRB990123, 15-GHz limits
- GRB 990123: New Constraints on Possible Foreground Galaxies
- GRB990123 Optical Observations
- GRB990123, Probability of gravitational lensing
- GRB 990123: Detection of the IR Transient, and the Light Curve Fits
- GRB 990123: Continued Radio Observations
- GRB 990123: Strong MeV CGRO-COMPTEL detection now posted on WWW
- GRB 990123 Optical Follow-Up
- GRB 990123; Addendum to GCN 223
- GRB 990123 : Multiple and Distorted Images of the Host Galaxy?
- GRB 990123 Optical Follow-Up
- GRB 990123: Possible Gravitationally Lensed Burst?
- GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
- GRB 990123 radio observations
- GRB990123, early optical counterpart detection
- GRB990123, BeppoSAX-NFI X-ray afterglow detection
- GRB990123, BeppoSAX WFC detection and NFI planned follow-up
- GRB981220
- GRB 981220 Optical observations
- GRB 981226 Optical Observations
- GRB 981226
- GRB 981226 optical observations
- GRB981220 B, R and I band observations
- Optical Observations of GRB981226
- GRB 981220
- GRB 980326/Host Galaxy
- GRB 980923 BATSE Observations
- Optical Observations of the Host Galaxy of GRB 980519
- GRB980703 - BeppoSAX/GRBM detection
- RXTE Observation of GRB 980706
- GRB980703: LOTIS observation at early times