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').
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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"11759 results found.
- LIGO/Virgo G275404 and G275659: SkyMapper Follow-up Observations
- LIGO/Virgo G284239: H.E.S.S. very-high energy gamma-ray follow-up
- LIGO/Virgo G284239: MAXI/GSC observations
- GRB 170510A: Fermi-LAT detection
- LIGO/Virgo G284239:SVOM/Mini-GWAC observations of the initial skymap
- LIGO/Virgo G284239: MASTER automatic follow up and synchronous observations
- LIGO/Virgo G284239: Fermi-LAT search for a high-energy gamma-ray counterpart
- LIGO/Virgo G284239: TZAC TAROT network observations with TRE/TCA/TCH
- LIGO/Virgo G284239: AGILE GRID observations
- Short GRB 170428A: MASTER-OAFA final reduction of the optical observations
- Konus-Wind observation of GRB 170428A
- Konus-Wind observation of GRB 170424A
- GRB 170424A: Fermi-LAT detection
- Fermi GBM trigger 514379207/170420463 is not a GRB
- GRB 170419A: Swift-XRT refined Analysis
- GRB 170419A: Swift detection of a burst
- LIGO/Virgo G275404: DLT40 follow-up observation
- LIGO/Virgo G277583: DLT40 follow-up observation
- Konus-Wind observation of GRB 170409A
- GRB 170409A: Fermi GBM Observation
- GRB 170409A: Fermi-LAT detection
- GRB170405A, Swift-UVOT Detection
- GRB 170405A: Swift-XRT refined Analysis
- Konus-Wind observation of GRB 170405A
- GRB 170405A: ISON/Terskol optical observations
- GRB 170405A: Watcher optical detection
- GRB 170405A: Fermi-LAT detection
- GRB 170330A CALET Gamma-Ray Burst Monitor detection
- GRB 170325A: optical observations, possible OT/host detection
- Konus-Wind observation of GRB 170403A (short/hard)
- Konus-Wind observation of GRB 170330A
- Fermi-LAT Gamma-ray Observations of IceCube-170321
- IceCube-170321A: Swift-XRT observations
- GRB 170331A: Swift-XRT refined Analysis
- LIGO/Virgo G275697: LOFAR follow-up
- Konus-Wind observation of GRB 170329A
- GRB 170331A: Swift detection of a burst
- GRB 170329A: Fermi-LAT detection
- INTEGRAL pointed follow-up of IceCube-170321A
- Konus-Wind observation of GRB 170320A
- LIGO/Virgo G277583: INTEGRAL search for an X-ray and gamma-ray counterpart
- GRB 170318A: KAIT Optical Upper Limit
- GRB 170318B: Swift-BAT refined analysis
- GRB 170318A: Swift-BAT refined analysis
- GRB 170318A: Prompt enhanced Swift-XRT position
- IceCube-170312A: MASTER follow-up observations
- LIGO/Virgo G277583 : MAXI/GSC observations
- GRB 170317A: Mondy optical observations
- GRB 170317A: ISON-Ussuriysk aferglow confirmation
- LIGO/Virgo G277583: ATLAS coverage and transients over the first 2 days
- LIGO/Virgo G275697: DLT40 follow-up observation
- LIGO/Virgo G274296: DLT40 follow-up observation
- LIGO/Virgo G275697: Fermi-LAT search for a high-energy gamma-ray counterpart
- LIGO/Virgo G277583: ERRATUM LV GCN 20871: TAROT Calern (TCA) observations
- LIGO/Virgo G277583: TAROT Calern (TCA) observations
- LIGO/Virgo G277583: SVOM/Mini-GWAC observations of the initial skymap
- Konus-Wind observation of GRB 170311B
- GRB 170309A: POLAR Observation
- GRB170306A: SALT observations
- LIGO/Virgo G275404: Swift-XRT observations of sources in the AGILE error region
- GRB 170305A: POLAR observation
- GRB 170307A: Fermi GBM observation
- Swift Trigger 741528: a possible GRB
- Konus-Wind observation of GRB 170306B
- GRB 170306A, Swift-BAT refined analysis
- GRB 170306B: Fermi-LAT detection
- GRB 170306A: GROND observations
- LIGO/Virgo G275697: Further Swift-XRT sources
- GRB 170306A: LCO Cerro Tololo observations
- GRB 170306A: Swift detection of a burst
- LIGO/Virgo G275404: Liverpool Telescope classification of EM candidates
- LIGO/Virgo G275697: Further Swift-XRT sources
- Konus-Wind observation of GRB 170228A
- LIGO/Virgo G275697: MAXI/GSC observations
- GRB 170228B CALET Gamma-Ray Burst Monitor detection
- LIGO/Virgo G275697: Additional iPTF Optical Transient Candidates
- LIGO/Virgo G275404: Additional iPTF Optical Transient Candidates
- LIGO/Virgo G275404: Nearby Galaxies in the Localization Volume
- LIGO/Virgo G268556, G270580, G274296, and G275404: Konus-Wind observations
- LIGO/Virgo G275404: iPTF Optical Transient Candidates
- GRB 170228A: Fermi-LAT detection
- LIGO/Virgo G275404: A near-infrared transient in the error circle of AGL J1914+1043
- LIGO/Virgo G275697: CNEOST optical observations
- LIGO/Virgo G274296 and G275404 : MAXI/GSC observations
- LIGO/Virgo G275404: Nearby galaxy observations by J-GEM collaboration
- LIGO/Virgo G275404: Nearby Galaxies in the Localization Region
- LIGO/Virgo G275697: Fermi-LAT search for a high-energy gamma-ray counterpart
- LIGO/Virgo G275697: INTEGRAL search for a prompt gamma-ray counterpart
- LIGO/Virgo G275404: Fermi-LAT search for a high-energy gamma-ray counterpart
- LIGO/Virgo G275404: AGILE-GRID detection of a possible gamma-ray transient
- LIGO/Virgo G275404: SVOM/Mini-GWAC: Observations of initial skymap
- GRB 170220A: POLAR Observation
- Konus-Wind observation of GRB 170222A
- LIGO/Virgo G274296: CALET Observations
- LIGO/Virgo G274296: PS17bek is a superluminous supernova at z=0.31
- LIGO/Virgo G274296: J-GEM optical/NIR follow-up observations
- GRB 170219A: POLAR Observation
- Swift Trigger 739517 is probably not a GRB
- LIGO/Virgo G274296: Asiago 1.82m Optical Observations
- LIGO/Virgo G274296: PSN MASTER OT J042250.16-820415.4 is before maximum