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').
107 results found.
- Fermi GRB 210324B: Global MASTER-Net observations report
- GRB 201216C: Swift/UVOT Upper Limits
- Fermi GRB190425.09 Global MASTER-Net observations report
- Swift triggered on SAX J1806.5-221
- GRB 160409A found in Swift BAT ground analysis
- GRB 160119A: Swift/UVOT Upper Limits
- Trigger 659734: Swift detection of SAX J1750.8-2900 or other source near Galactic center
- Swift detection of SAX J1808.4-3658
- GRB 150110B: Enhanced Swift-XRT position
- Swift detection of SAX J1712.6-3739
- Swift-BAT trigger 536502 is not astrophysical
- Swift Trigger 536502 is likely a noise fluctuation in coincidence with SAX J1818.6-1703
- Swift-BAT trigger 535733 is not astrophysical
- Trigger 535733: Swift possible detection of SAX J1828.5-1037
- SAX J1818.6-1703: Swift detection (trigger 306379)
- UVOT observations of SAXJ1810.8-2609
- Swift detection of a outburst from SAX J1810.8-2609
- GRB050802: TNG optical observations
- GRB 050802.422: Fading of the afterglow and detection of the host
- GRB050802: Tentative absorption redshift
- GRB 050802: Swift/UVOT optical and UV detections
- GRB050802: CrAO optical observations
- GRB 050802: early Swift XRT analysis results
- H11603: An X-ray flare from V4641 Sgr, or a possible XRF
- 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
- GRB990123, Probability of gravitational lensing
- GRB990123 IPN annulus
- GRB990123, refined SAX-WFC position
- GRB 981226 Optical Observations
- GRB981226 BeppoSAX follow up
- GRB980425: X-ray revised positions
- GRB980519, Optical Observations
- GRB980703, Host galaxy multicolor photometry
- GRB 980703 (NFI observations)
- BeppoSAX NFI observations of GRB 980703
- GRB980703
- GRB980613, optical observations
- GRB 980613 Optical Observations
- GRB980613 BeppoSAX-NFI follow up
- GRB980613, BeppoSAX WFC positions
- GRB980519 IPN POSITION
- GRB980515: SAX-WFC updated position
- BSAX Observations of GRB980425 field
- GRB980425 BATSE observations
- SAX J0840.7+2248 Optical Observations
- report on BSAX observations of GRB980425
- GRB980329 IPN annulus
- GRB980329 near-IR observations
- GRB980329 near-IR observations