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"- LIGO/Virgo G298048: SRT observations of SSS17a in NGC 4993
- GRB 170921A: Swift/UVOT Upper Limits
- GRB 170921A: Swift-BAT refined analysis
- GRB 170918A: Insight-HXMT detection
- GRB 170921A: LCO 2m telescope observations
- GRB 170921A: NOT optical observations
- LIGO/Virgo G298048: LCO FLOYDS and Gemini Spectroscopy
- GRB 170921A: Nanshan optical upper limit
- GRB 170921A: Enhanced Swift-XRT position
- GRB 170921A: MITSuME Okayama upper limits
- GRB 170921A: Swift-XRT refined Analysis
- GRB 170921A: TAROT Calern observatory optical observations
- GRB 170921B: Fermi GBM detection
- GRB 170921A: Swift detection of a burst
- LIGO/Virgo G298048: ATCA monitoring of SSS17a in NGC 4993
- LIGO/Virgo G298048: Limits from an FRB search of SSS17a with the Parkes 64m Radio Telescope
- LIGO/Virgo G298048: SSS17a photometry of CHILESCOPE observatory
- LIGO/Virgo G298048: Milliarcsecond imaging of the NGC 4993 central radio source
- Swift trigger 773082 is probably not astrophysical
- LIGO/Virgo G298048: TOROS photometry of SSS17a
- LIGO/Virgo G298048: Desert Fireball Network simultaneous optical observations of the SSS17a/DLT17ck.
- Fermi-GBM GRB misclassifications
- GRB 170912C: Insight-HXMT detection
- LIGO/VIRGO G298048: MeerKAT observations of SSS17a
- LIGO/Virgo G297595: NIR Observations following GW170814
- LIGO/Virgo G298048: Danish Telescope Observations of SSS17a/DLT17ck
- LIGO/Virgo G297595: PIRATE observations
- Fermi GBM trigger 527149931/170915272 is not a GRB
- LIGO/Virgo G298048: ATLAS pre-discovery limits 601 to 16 days before first detection of SSS17a/DLT17ck
- LIGO/Virgo G297595: LSGT observation of nearby galaxies
- GRB 170906A CALET Gamma-Ray Burst Monitor detection
- LIGO/Virgo G298048: AST3-2 observations of SSS17a/DLT17ck from Antarctica
- LIGO/Virgo G298048: ATCA monitoring of SSS17a in NGC 4993
- GRB 170912B: Swift/UVOT Upper Limits
- Fermi GBM trigger 526978609/170913289 is not a GRB
- GRB 170912B: Swift-BAT refined analysis
- LIGO/Virgo G297595: DLT40 follow-up observation
- GRB 170912A: Swift-BAT refined analysis
- GRB 170912A: Swift-XRT refined Analysis
- LIGO/Virgo G299232: Khureltogot observations
- GRB 170912A: Swift/UVOT Upper-Limits
- GRB 170912B: Swift-XRT refined Analysis
- GRB 170912B: Fermi GBM observations
- LIGO/Virgo G298936: Konus-Wind observations
- LIGO/Virgo G299232: Konus-Wind observations
- GRB 170911A: Fermi GBM observation
- GRB 170912B: Enhanced Swift-XRT position
- LIGO/Virgo G299232: Pierre Auger Observatory follow-up
- LIGO/Virgo G298389: Pierre Auger Observatory neutrino follow-up
- GRB 170912B: Swift detection of a burst
- GRB 170912A: Enhanced Swift-XRT position
- GRB 170912A: Prompt enhanced Swift-XRT position
- GRB 170912A: Swift detection of a burst
- LIGO/Virgo G297595: Las Cumbres Observatory Optical Follow-Up
- Konus-Wind observation of GRB 170906A
- GRB 170911A: MAXI/GSC detection
- Konus-Wind observation of GRB 170906C
- GRB 170906A: AstroSat CZTI(Veto) detection
- GRB 170830B CALET Gamma-Ray Burst Monitor detection
- IBAS Alert nr. 7913 is not a real GRB
- Fermi-GBM GRB mis-classifications during current Solar activity
- Konus-Wind observation of GRB 170904A
- LIGO/Virgo G298048: VLA radio non-detection
- LIGO/Virgo G298048: VLBA upper limits at 8.7GHz for the GW counterpart SSS17a/DLT17ck on August 20-21 UT
- Swift Triggered on MAXI J1535-571
- LIGO/Virgo G298048: LWA Detection
- GRB 170906A: Swift/UVOT Detection
- GRB 170906B: Swift/UVOT Upper Limits
- GRB 170906B: Swift-XRT refined Analysis
- LIGO/Virgo G299232: Swift-XRT sources
- GRB 170906C: optical observations
- LIGO/Virgo G298048: ATCA observations of of SSS17a in NGC 4993
- GRB 170906B: Swift-BAT refined analysis
- GRB 170906B: Fermi GBM detection
- GRB 170906A: Fermi GBM detection
- GRB 170906A: Swift-BAT refined analysis
- GRB 170906C: COATLI Observations
- GRB 170906A: Swift-XRT refined Analysis
- GRB 170906C: Swift/UVOT Upper Limits
- GRB 170906C: Swift-XRT refined Analysis
- LIGO/Virgo G298048 GRAWITA: VST-ESO PARANAL follow up of SSS17a in NGC4993.
- GRB 170906C: Swift-BAT refined analysis
- GRB 170906C: Enhanced Swift-XRT position
- GRB 170906A: MASTER-OAFA (Argentina) early automatic OT detection
- GRB 170829A: Insight-HXMT detection
- GRB 170906C: Swift-XRT observations
- GRB 170906A: Fermi-LAT detection
- GRB 170906C: Swift detection of a burst
- GRB 170906A: REM optical/NIR observations
- GRB 170906A: Enhanced Swift-XRT position
- GRB 170906B: Enhanced Swift-XRT position
- GRB 170906B: Swift detection of a burst
- GRB 170906A: Swift detection of a burst with an optical afterglow
- IPN Triangulation of GRB 170904A (long/very bright)
- LIGO/Virgo G299232: Lulin Observations of Possible OTs
- GRB 170901B: Insight-HXMT detection
- GRB 170904A: Insight-HXMT detection
- LIGO/VIRGO G298048: Precise position of SSS17a based on HST and Gaia
- LIGO/VIRGO G298048: Radio detection of SSS17a at 6 GHz with the VLA
- LIGO/VIRGO G298048: Radio detection of SSS17a at 3GHz with the VLA/JAGWAR