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"
10364 results found.
- SGR1806-20: A Second, Intense Burst Localized by HETE
- SGR1806-20: Localization by HETE
- X-ray precursors to the large flare from SGR 1900+14
- GRB010427, Gamma Ray Observations
- BeppoSAX/NFI Follow-up Observation of SGR 1900+14
- SGR 1900+14, Chandra observations
- GRB010326: Localization by HETE
- GRB010214, field photometry
- GRB010222, field photometry
- GRB010214B,Gamma Ray Observations
- BeppoSAX ALERT: GRB010220
- GRB010214: BeppoSAX WFC and GRBM preliminary data
- GRB 010214, Optical Observations
- J-Band Observation of GRB 010214.
- Possible InfraRed Transient of GRB 010214.
- GRB010214 Optical Observation
- GRB 010214, optical observations
- HETE Status
- GRB010126 opt. obs.
- IPN/RXTE TRIANGULATION OF GRB010126
- GRB010126 optical observations
- IPN/RXTE TRIANGULATION OF GRB010126
- IPN TRIANGULATION OF GRB010115
- IPN triangulation of GRB001219
- GRB 001212 optical observation
- IPN triangulation of GRB001120
- GRB 001109 X-ray afterglow with BeppoSAX
- GRB001109: Optical observations
- GRB001109: BeppoSAX/NFI Observations
- XMM-Newton observation of GRB001025
- IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
- CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
- ASM Localization of GRB 001025
- GRB001018, Gamma Ray Observations
- IPN TRIANGULATION OF GRB001019
- GRB 000926 Chandra Observation
- IPN triangulation of GRB 001004
- GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
- GRB000926 K'-band Observation
- IPN triangulation of GRB000925
- IPN triangulation of GRB000910
- IPN triangulation of GRB000830
- HST/STIS observations of the host galaxy of GRB 980329
- SGR 1806-20 burst activity
- GRB000801 & GRB000730, Gamma Ray Observations
- GRB000730, Gamma Ray Observations
- GRB000801, Gamma Ray Observations
- possible optical counterpart of GRB 000630
- IPN triangulation of GRB000630
- GRB 000623, optical observations
- GRB000620, optical observations
- GRB000620: BeppoSAX WFC and GRBM detection
- BeppoSAX ALERT: GRB000620
- GRB000620: BeppoSAX Alert
- GRB000616 [IPN Position]
- GRB000615B [IPN Position]
- GRB000615: BeppoSAX NFI follow-up preliminary analysis
- GRB000528: BeppoSAX NFI follow-up preliminary analysis
- GRB000519: Optical observations
- IPN triangulation of GRB000516
- GRB 000429, optical observation
- GRB 000418, UBVRI field photometry
- GRB 000418, Optical Observation
- GRB 000418, optical observation
- GRB 000418, Optical Observation
- GRB 000418, Optical Observation
- GRB000418, near-infrared observations
- IPN error box for GRB000418
- BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
- GRB 000408, optical observations
- GRB000313, Radio observations
- GRB000301C - B and R photometry
- GRB 000307, BVRI Field Photometry
- IPN error box for GRB000307
- GRB 000301C, UBVRI field photometry
- GRB 000301C, Optical Observation
- GRB 000301A, Radio Observations
- GRB 000301C : Optical Candidate
- GRB000226 [IPN Position]
- GRB 000115 Optical observations
- BATSE GRB trigger criterion changed
- GRB 000210: BATSE Observations
- GRB000210: BeppoSAX GRBM and WFC Detection
- GRB000201 Optical Observations
- BATSE Observations of GRB000115
- GCN resumes full operations
- Chandra observation of the X-ray afterglow of GRB991216
- GRB 991216 Optical spectroscopy/imaging
- GRB 991216 Optical Observation
- GRB 991216: Extremely bright BATSE burst
- IPN localization of GRB991208
- GRB 991105: BATSE Observations
- GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
- GRB 990915 optical observations
- BATSE GRB trigger criteria
- GRB990907: BeppoSAX follow up and X-ray afterglow
- GRB990806: BATSE Observations
- GRB 990705, R-band observations
- Infrared and Optical Observations of GRB990705
- GRB990704