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 170726A: Insight-HXMT detection
- GRB 170724A, Swift-BAT refined analysis
- GRB 170724A: Swift detection of a burst
- Fermi GBM trigger 522477026/170723188 is not a GRB
- Fermi GBM trigger 522470841/170723116 is not a GRB
- Fermi GBM trigger 522334209/170721535 is not a GRB
- GRB170714A: ATCA observation
- GRB 170714A: Bastille Day Burst redshift from OSIRIS/GTC
- Trigger 763539 from Swift is probably not astrophysical
- Fermi GBM trigger 522048561/170718229 is not a GRB
- GRB 170714A: NOEMA non-detection of the Bastille Day Burst
- LIGO/Virgo G275697: LOFAR follow-up
- GRB 170710B: Further Swift-XRT observations
- Correction to GCN Circular 21351: GRB 170714A: Swift/UVOT Observations
- GRB170714A: VLA Observations of the Bastille Day Ultra-long Burst
- GRB 170714A: Swift/UVOT Observations
- GRB 170714A: TNG NIR observations
- Fermi GBM trigger 521905898/170716577 is not a GRB
- GRB 170702A: AstroSat CZTI detection
- GRB 170714A, Swift-BAT refined analysis
- GRB 170714A: z-band afterglow candidate for OSIRIS/GTC
- GRB 170714A: Bastille Day Burst: ULGRB or RTDE?
- GRB 170714B: Insight-HXMT detection
- GRB 170714A: Swift-XRT refined Analysis
- Fermi GBM Detection of possible burst from AXP 4U 0142+61
- GRB 170714A: Enhanced Swift-XRT position
- GRB 170714A: Swift detection of a burst
- GRB 170712A: AstroSat CZTI detection
- Correction to GCN Circular 21337: GRB 170710D CALET Gamma-Ray Burst Monitor detection
- GRB 170710D CALET Gamma-Ray Burst Monitor detection
- GRB 170708B CALET Gamma-Ray Burst Monitor detection
- GRB 170703A CALET Gamma-Ray Burst Monitor detection
- GRB 170702A CALET Gamma-Ray Burst Monitor detection
- GRB 170711A: ISON/Terskol and AbAO optical observations
- GRB 170712A: Insight-HXMT detection
- GRB 170711A: Swift-BAT refined analysis
- Konus-Wind observation of GRB 170708A
- GRB 170711A: Swift/UVOT Upper Limits
- GRB 170711A: RATIR Optical and NIR Observations
- GRB 170705A: AstroSat CZTI detection
- 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