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"
333 results found.
- GRB 090410: Swift-BAT refined analysis
- GRB 090407: Swift UVOT Upper Limits
- GRB 090301A: Suzaku WAM observation of the prompt emission
- GRB 090206: Fermi GBM detection
- GRB 090202: Fermi GBM detection
- GRB 080928, Swift-BAT final refined analysis
- GRB 080928, Swift-BAT initial refined analysis
- GRB 080916A: Swift XRT refined analysis
- GRB 080825C: Fermi GBM Spectral Analysis
- ATCA radio upper limit on GRB 080723B
- GRB 080503, Swift-BAT lag and time-resolved spectral analysis
- GRB 080503, Swift-BAT refined analysis
- GRB 080413A: Suzaku/WAM and Swift/BAT joint spectral analysis
- SAX J1818.6-1703: Swift detection (trigger 306379)
- GRB 080205: Swift XRT refined analysis
- GRB 070911: Swift/BAT and Suzaku/WAM joint spectral analysis
- UVOT observations of SAXJ1810.8-2609
- Swift detection of a outburst from SAX J1810.8-2609
- GRB 070714B: Swift/UVOT Upper Limits
- GRB 070531: Swift-BAT refined analysis
- GRB 070520B: Swift-XRT refined analysis
- GRB 070318, Swift-BAT refined analysis
- GRB 070110: Ep,i - Eiso correlation
- GRB 061201: Swift detection of a short hard burst
- GRB 061019, Swift-BAT refined analysis
- GRB060319: MASTER limit
- GRB060319: MASTER optical observation
- GRB 050904: early Swift XRT analysis results
- Swift/UVOT photometry of GRB050730
- GRB050724: Radio Observation
- H11603: An X-ray flare from V4641 Sgr, or a possible XRF
- Swift/UVOT observation of XRF 050522
- GRB050309: CONCAM pre-trigger and trigger coincident optical
- Konus-Wind observation of a series SGR 1806-20 bursts on 041005
- XMM-Newton Observation of GRB031203
- XMM-Newton Observation of GRB031203
- IPN triangulation of GRB030421 (annulus)
- BeppoSAX GRB : GRB020409
- GRB020322: Candidate Optical Afterglow
- Bepposax GRB020322 The second springtime BSAX GRB
- GRB 011211 Optical Observations: Likely Afterglow
- Detection of the X-ray afterglow of GRB011121 by BeppoSAX
- GRB011121: BeppoSAX-WFC refined positions
- BEPPOSAX GRB011121
- The X-ray Flash 011030 ('GRB 011030')
- IPN triangulation of GRB010629
- Support extension to the BeppoSAX mission
- GRB010222: possible optical counterpart
- GRB010222
- GRB 010214, Optical Observations
- GRB000528, Radio Observations
- IPN triangulation of GRB000516
- BeppoSAX GRB000424
- GRB000419 [IPN Position]
- 1SAXJ1715.0-7134 refined position
- RE: Budget cuts in BeppoSAX operations: impact on GRB observation
- X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
- Budget cuts in BeppoSAX operations: impact on GRB observations
- GRB000226 [IPN Position]
- GRB 000210: BATSE Observations
- GRB000210, Radio Observations
- SAX_WFC_GRB_NOTICE
- SAX_WFC_GRB_NOTICE
- GCN resumes full operations
- IPN error box for GRB991216
- GRB 991217 (SAX J2303.2+0015) Optical observations
- GRB991217/SAX J2303.2+0015, optical observations
- SAX J2303.2+0015 Optical observations
- GRB 991217 (SAX J2303.2+0015) Optical observations
- GRB 991217
- SAX J2303.2+0015: an x-ray/GRB?
- BeppoSAX NFI Observation of GRB991106
- GRB 991105: BATSE Observations
- BeppoSAX refined position for GRB991106
- GRB991105: SAX-GRBM/-WFC detection
- BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
- GRB ALERT: GRB991105
- GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
- GRB990908, another BeppoSAX-GRBM/WFC burst detection
- GRB990806 BeppoSAX follow up
- GRB 990712
- Infrared and Optical Observations of GRB990705
- GRB990704: SAX-NFI results summary
- GRB 990704 X-ray Observations
- GRB990705: Intriguing Positional Coincidences
- X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
- optical observation of the X-ray/GRB transient SAX J0835.9+5118
- Optical report on X-ray/GRB transient
- BeppoSAX: A new fast X-ray transient
- GRB981220 VLBA observations
- GRB981220, IPN localization
- GRB 981220, radio observations
- GRB990123, Probability of gravitational lensing
- GRB990123 IPN annulus
- GRB990123, refined SAX-WFC position
- GRB 990123, Radio observations
- Optical Observations of GRB 981220
- GRB981220
- GRB981220, Optical Observations
- GRB 981220 Optical observations