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.
Advanced Search Examples (click to copy):
subject:"Swift"body:"GRB"submitter:"Judith Racusin"11778 results found.
- 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
- LIGO/Virgo G274296: PESSTO classification of 9 Pan-STARRS transients
- LIGO/Virgo G274296: Fermi-LAT search for a high-energy gamma-ray counterpart
- Konus-Wind observation of GRB 170219A (short/hard)
- IPN Triangulation of GRB 170219A (short/hard)
- LIGO/Virgo G274296: Optical Observation
- LIGO/Virgo G274296: Pan-STARRS imaging and discovery of 70 transients
- LIGO/Virgo G274296: SWASP optical imaging coverage
- LIGO/Virgo G274296: Observations of initial skymap by project Mini-GWAC of SVOM
- LIGO/Virgo G274296: REM optical/NIR observations
- GRB 170214A: Mondy optical upper limit
- Konus-Wind observation of GRB 170214A
- GRB 170214A: Fermi-LAT detection
- LIGO/Virgo G270580: DLT40 follow-up observation
- Konus-Wind observation of GRB 170210A
- GRB 170210A: POLAR observation
- GRB 170208C: POLAR Observation
- IPN Triangulation of GRB 170210A
- Konus-Wind observation of GRB 170209A
- GRB 170208B: Swift-BAT refined analysis
- LIGO/Virgo G270580: AstroSat CZTI upper limits
- GRB 170207A: POLAR Observation
- Konus-Wind observation of GRB 170208B
- Konus-Wind observation of GRB 170208A
- GRB 170206C: POLAR Observation
- GRB 170208B: Swift-XRT refined Analysis
- GRB 170208B: Swift detection of a burst
- Konus-Wind observation of GRB 170207A
- Konus-Wind observation of GRB 170206A
- GRB 170206A: POLAR observation
- IPN Triangulation of GRB 170206A (short/hard)
- GRB 170206A: Fermi-LAT detection
- Konus-Wind observation of GRB 170205A
- Konus-Wind observation of GRB 170202A
- GRB 170202B POLAR Observation
- GRB 170131A: POLAR Observation
- GRB 170202A: Swift-XRT refined Analysis
- GRB 170202A: T100 observations
- GRB 170131A detected in Swift/BAT ground processing
- LIGO/Virgo G270580: Las Cumbres Observatory Follow-up Observations
- GRB 170130A: POLAR Observation
- Konus-Wind observation of GRB 170127C (short/hard GRB with extended emission)
- GRB 170127B: Swift-BAT refined analysis
- GRB 170127C: POLAR Observation
- GRB 170127B: Swift-XRT refined Analysis
- GRB 170127A: Swift-XRT refined Analysis
- GRB 170124A: CALET Gamma-Ray Burst Monitor detection
- Konus-Wind observation of GRB 170126A
- GRB 170127C (Fermi/GBM trigger 507173752): AGILE analysis
- GRB 170127C: Fermi-LAT detection
- GRB 170127B: Swift detection of a short burst
- GRB 170126A: Swift-XRT refined Analysis
- LIGO/Virgo G270580: MAXI/GSC observations
- LIGO/Virgo G270580: No change to estimate of LIGO false alarm probability
- LIGO/Virgo G270580: Liverpool Telescope classification of EM candidates
- LIGO/Virgo G270580: Pan-STARRS coverage and 124 optical transients
- LIGO/Virgo G270580: UL50 observations
- GRB 170121B: MASTER early optical observations of the Swift possible XT
- LIGO/Virgo G270580: CALET Observations
- LIGO/Virgo G268556/GW170104: MAXI/GSC observations
- GRB 170120A: POLAR Observation
- LIGO/Virgo G270580: Fermi-LAT search for a high-energy gamma-ray counterpart
- LIGO/Virgo G270580: Two optical counterpart candidates from CNEOST
- LIGO/Virgo G270580: INTEGRAL search of temporally coincident prompt hard X-ray
- LIGO/Virgo G268556: Global MASTER Net 21 OTs detection
- LIGO/Virgo G270580: Mini-MegaTORTORA follow-up observations
- LIGO/Virgo G270580: Pan-STARRS and ATLAS observations of the skymap
- LIGO/Virgo G270580: Observations of initial skymap by Project Mini-GWAC of SVOM
- LIGO/Virgo G270580: AGILE MCAL and Super-AGILE Observations
- LIGO/Virgo G270580: Identification of a GW Burst Candidate
- Konus-Wind observation of GRB 170115B
- GRB 170115A: Swift-XRT refined Analysis
- GRB 170115B: Fermi-LAT detection
- GRB 170115A: Swift detection of a burst
- LIGO/Virgo G268556: spectra of two nuclear transients PS17fr and PS17er
- GRB 161219B: afterglow and SN2016jca optical observations
- GRB 170111A: Swift-BAT refined analysis
- GRB 170111A: Swift-XRT refined Analysis
- LIGO/Virgo G268556/GW170104: Campo Imperatore Observatory observations
- LIGO/Virgo G268556: AMI 15 GHz detection of ATLAS17aeu
- GRB 170111A: Swift detection of a burst
- LIGO/Virgo G268556: Spectroscopic observations of ATLAS17aeu and iPTF17cw