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').
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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.
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subject:"Swift"body:"GRB"submitter:"Judith Racusin"- GRB 170710C: a long GRB detected by INTEGRAL
- GRB 170711A: Swift-XRT refined Analysis
- GRB 170711A: Fermi GBM observation
- GRB 170711A: Enhanced Swift-XRT position
- GRB 170711A: Prompt enhanced Swift-XRT position
- GRB 170711A: Swift detection of a burst
- GRB 170705A: TShAO optical observations
- GRB 170710B: Fermi GBM observation
- GRB 170710B: Swift-XRT and UVOT observations
- GRB 170710B: Swift ToO observations
- GRB 170710B: Swift detection of a burst
- GRB170710A: Swift/UVOT detection
- IPN Triangulation of GRB 170708A (short)
- GRB 170710A: Swift-BAT refined analysis
- GRB 170710A: Swift-XRT refined Analysis
- GRB 170710A: Gemini-S candidate counterpart
- GRB 170710A: Enhanced Swift-XRT position
- GRB 170710A: Prompt enhanced Swift-XRT position
- GRB 170710A: Swift detection of a burst
- GRB 170708A: Insight-HXMT detection
- Correction to GCN Circular 21305: Trigger 760835: Swift misidentification of GRS1716-249
- Trigger 760835: Swift misidentification of GRS1716-249
- LIGO/Virgo G288732: Konus-Wind observations
- GRB 170705A: Further RATIR Optical and NIR Observations and Steepening of Fading
- GRB 170705A: KAIT Optical Observations
- GRB 170705A: Insight-HXMT observation
- GRB 170705A: ISON/Terskol optical observations
- Konus-Wind observation of GRB 170705A
- GRB 170705A: Redshift from 10.4m GTC/OSIRIS
- GRB 170705A: Fermi GBM observation
- GRB 170705A: Swift-BAT refined analysis
- GRB 170705A: MITSuME Akeno Optical Observation
- GRB 170705A: Swift/UVOT Detection
- GRB 170705A: RATIR Optical and NIR Observations
- GRB 170705A: Swift-XRT refined Analysis
- GRB 170705A: MASTER-OAFA early OT observations
- GRB 170705A: Enhanced Swift-XRT position
- GRB 170705A: Swift detection of a burst with an optical counterpart
- GRB 170629A: Swift-XRT refined Analysis
- GRB 170629A: Swift-BAT refined analysis
- GRB 170629A: Enhanced Swift-XRT position
- GRB 170629A: Fermi GBM observation
- LIGO/Virgo G274296: Updated localization from LIGO data
- GRB 170629A: Swift detection of a burst
- GRB 170626B CALET Gamma-Ray Burst Monitor detection
- LIGO/Virgo G270580: Candidate retracted due to H1 data quality
- Konus-Wind observation of GRB 170626B
- IPN Triangulation of GRB 170626B
- Konus-Wind observation of GRB 170626A
- GRB 170626A: SAO RAS confirmation of OT fading
- GRB 170626A: TShAO optical observations
- GRB 170607A: 15 GHz upper limits from AMI
- GRB 170626A: Insight-HXMT observation
- GRB 170626A: OASDG optical observations
- GRB 170626A: MASTER-Tunka OT detection.
- GRB 170626A: Swift-BAT refined analysis
- GRB 170626A: TNG optical observations
- GRB 170626A: Afterglow detection from 1.5m OSN
- GRB 170626A: SAO RAS possible OT detection
- GRB 170626A: Swift-XRT refined Analysis
- GRB 170626A: Fermi GBM observation
- GRB 170626B: The first GRB detected by the Insight-HXMT X-ray Telescope (revised)
- GRB 170626A: Swift detection of a burst
- LIGO/Virgo G288732: Fermi GBM Upper Limits for the LIGO Trigger and LAT Candidate
- LIGO/Virgo G288732: Pan-STARRS coverage of the Fermi/LAT candidate position
- Swift trigger 758168 is probably not an astrophysical source
- Swift Trigger 758005 is Probably Not an Astrophysical Source
- GRB 170607A CALET Gamma-Ray Burst Monitor detection
- Konus-Wind observation of GRB 170616A
- IPN Triangulation of GRB 170616A (short/hard)
- GRB 170614A: AstroSat CZTI detection
- GRB 170614A CALET Gamma-Ray Burst Monitor detection
- GRB 170606A CALET Gamma-Ray Burst Monitor detection
- LIGO/Virgo G288732: VLA imaging of the possible Fermi/LAT counterpart
- Swift Trigger 756953: false identification by MASTER GCN 21250
- Swift Trigger 756953 is probably not an astrophysical source
- GRB170612.87 MASTER-Net OT detection
- LIGO/Virgo G288732: Kiso/KWFC optical imaging of the possible Fermi/LAT counterpart
- LIGO/Virgo G288732: HAWC follow-up
- Konus-Wind observation of GRB 170604A
- Konus-Wind observation of GRB 170607B
- LIGO/Virgo G288732: UKIRT near-IR imaging of the Fermi/LAT candidate
- LIGO/Virgo G288732: LBT optical imaging of the Fermi/LAT candidate
- GRB 170610A: MAXI/GSC detection
- IPN Triangulation of GRB 170607B
- LIGO/Virgo G288732 : MAXI/GSC observations
- GRB 170607A: Redshift from GTC/OSIRIS
- LIGO/Virgo G288732: Updated sky map from gravitational-wave data
- GRB 170607B: Fermi GBM detection
- GRB 170607A: ISON/Terskol optical observations
- LIGO/Virgo G288732: GWFUNC/NOWT observations of the skymap and follow-up of the Fermi/LAT candidate
- LIGO/Virgo G288732: Swift/UVOT follow up of the possible LAT counterpart
- LIGO/Virgo G288732: Swift/BAT data search
- LIGO/Virgo G288732: Swift-XRT follow up of the putative LAT counterpart
- GRB 170607B: AstroSat CZTI detection
- LIGO/Virgo G288732: INTEGRAL search for a prompt gamma-ray counterpart
- GRB 170607A: Swift-BAT refined analysis
- LIGO/Virgo G288732:SVOM/Mini-GWAC observations of the initial skymap
- LIGO/Virgo G288732: AGILE GRID Observations
- LIGO/Virgo G288732: Fermi-LAT detection of a weak candidate