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 170810A: Swift/UVOT Detection
- GRB 170810A: Fermi GBM observation
- GRB 170810A: Fermi-LAT detection
- GRB 170810A: Enhanced Swift-XRT position
- GRB 170810A: Swift detection of a burst with a bright optical counterpart
- GRB 170810A: MASTER-NET very bright OT detection
- LIGO/Virgo G296853: HAWC follow-up
- Konus-Wind observation of GRB 170808B
- LIGO/Virgo G296853: Super-AGILE observations
- LIGO/Virgo G296853: MASTER SN detection near center error-area
- GRB 170805B: Insight-HXMT observation
- GRB 170803B: Insight-HXMT detection
- Konus-Wind observation of GRB 170805B
- GMRT upper limit on the radio afterglow of GRB 170728B
- LIGO/Virgo G296853: no INTEGRAL data at the time of the event
- LIGO/Virgo G296853: Fermi-LAT search for high-energy gamma-ray counterpart
- LIGO/Virgo G296853: Fermi GBM Observations
- LIGO/Virgo G296853: AGILE GRID observations
- LIGO/Virgo G296853: Swift/BAT data search
- LIGO/Virgo G296853: MASTER follow up observations
- LIGO/Virgo G296853: AGILE MCAL observations
- LIGO/Virgo G296853 ANTARES search
- LIGO/Virgo G296853: IceCube neutrino observations
- LIGO/Virgo G296853: Identification of a GW Binary Merger Candidate
- GRB 170808B: Fermi LAT Detection
- GRB 170808B: Fermi GBM observation
- IPN Triangulation of GRB 170805B (short/hard)
- IPN Triangulation of GRB 170805A (short)
- GRB 170801A: Insight-HXMT detection
- Konus-Wind observation of GRB 170724A
- GRB 170714A: ATCA detection of the radio counterpart
- GRB 170807A: Swift-BAT refined analysis
- GRB 170808A: MAXI/GSC detection
- GRB 170805A: Insight-HXMT detection
- GRB 170807A: Swift detection of a burst
- GRB 170728B: TShAO, SAO RAS and AbAO optical observations
- GRB 170803A: Swift/BAT spectral lag results
- GRB 170804A: LCO Observations
- GRB 170804A: Swift-BAT refined analysis
- GRB 170804A: Swift/UVOT Detection
- GRB 170804A: Swift-XRT refined Analysis
- GRB 170804A: Enhanced Swift-XRT position
- GRB 170803A: Swift-BAT refined analysis
- GRB 170803A: Swift/UVOT Detection
- GRB 170804A: Swift detection of a burst with optical counterpart
- Swift Trigger 766161 is not a GRB
- GRB 170803A: Swift-XRT refined Analysis
- GRB 170803A: Enhanced Swift-XRT position
- GRB 170803A: Fermi GBM observation
- GRB 170803A: Swift detection of a burst with an optical counterpart
- GRB 170802A: Fermi GBM detection
- Swift Trigger 765783 is not an astrophysical event.
- GRB 160814A: Lomonosov BDRG gamma ray discovery
- GRB 170728B: time correction to MASTER GCN Circular 21391
- Swift J181723.1-164300: Swift detection of another pulse of the new Galactic source
- GRB 170728B: Swift/UVOT Further Analysis
- Konus-Wind observation of GRB 170728B
- GRB 170726A: AstroSat CZTI detection
- GRB 170714A: Chandra observations
- GRB 170728B: VLA radio afterglow detection
- GRB 170728B: Optical observations at Crni Vrh
- GRB 170728B: BOOTES-2/TELMA optical detection during the extended gamma-ray phase
- GRB170730A detecetd by INTEGRAL. Refined analysis
- GRB 170728B: MASTER-IAC first minute short GRB early OT detection
- IBAS weak Alert nr.7881: possible GRB 170730A
- GRB 170728B: COATLI Observations And Confirmation of Fading
- GRB 170728B: Swift/UVOT Upper Limits
- GRB 170728B iTelescope observation
- GRB 170728A: Swift/UVOT Detection
- Swift J181723.1-164300: Swift-BAT refined analysis
- GRB 170728B, Swift-BAT refined analysis
- GRB 170728B: Fermi GBM detection
- GRB 170728A: LCO observations
- GRB 170728B: I-band detection from 1.5m OSN
- GRB 170728B: Fermi-LAT detection
- GRB170714A: XMM observation of the afterglow
- GRB 170728A: Swift-XRT refined Analysis
- GRB 170728B: Enhanced Swift-XRT position
- GRB 170728B: Swift-XRT refined Analysis
- GRB 170728B: LT afterglow confirmation
- GRB 170728B: NOT optical afterglow confirmation
- GRB 170728B: position of the TNG optical counterpart
- GRB 170728B: TNG optical afterglow candidate
- GRB 170728B: Swift detection of a short burst
- GRB 170728A: Swift-BAT refined analysis
- Swift triggers on a new galactic source: Swift J181723.1-164300
- GRB 170728A: Enhanced Swift-XRT position
- GRB 170728A: Swift detection of a burst
- 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