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').
Advanced Search
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"14830 results found.
- Search for counterpart to IceCube-170922A with ANTARES
- GRB 170921B: AstroSat CZTI detection
- GRB 170906A: Insight-HXMT detection
- LIGO/Virgo G298048: Effelsberg 100-m Radio Telescope observations of SSS17a
- GRB 170921C: Insight-HXMT detection
- GRB 170921A: RATIR Optical Afterglow Detection and NIR Observations
- LIGO/Virgo G298048: SRT observations of SSS17a in NGC 4993
- GRB 170918A: Insight-HXMT detection
- GRB 170921B: Fermi GBM detection
- GRB 170921A: Swift detection of a burst
- Swift trigger 773082 is probably not astrophysical
- LIGO/Virgo G298048: Desert Fireball Network simultaneous optical observations of the SSS17a/DLT17ck.
- GRB 170912C: Insight-HXMT detection
- LIGO/Virgo G298048: ATLAS pre-discovery limits 601 to 16 days before first detection of SSS17a/DLT17ck
- GRB 170906A CALET Gamma-Ray Burst Monitor detection
- GRB 170912B: Swift detection of a burst
- GRB 170912A: Swift detection of a burst
- Konus-Wind observation of GRB 170906A
- GRB 170911A: MAXI/GSC detection
- GRB 170906A: AstroSat CZTI(Veto) detection
- GRB 170830B CALET Gamma-Ray Burst Monitor detection
- LIGO/Virgo G298048: VLA radio non-detection
- LIGO/Virgo G298048: LWA Detection
- GRB 170906A: Swift/UVOT Detection
- LIGO/Virgo G298048: ATCA observations of of SSS17a in NGC 4993
- GRB 170906B: Fermi GBM detection
- GRB 170906A: Fermi GBM detection
- GRB 170906A: MASTER-OAFA (Argentina) early automatic OT detection
- GRB 170829A: Insight-HXMT detection
- GRB 170906A: Fermi-LAT detection
- GRB 170906C: Swift detection of a burst
- 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: Radio detection of SSS17a at 6 GHz with the VLA
- LIGO/VIRGO G298048: Radio detection of SSS17a at 3GHz with the VLA/JAGWAR
- LIGO/Virgo G298048: e-MERLIN upper limits on 5 GHz compact emission from SSS17a
- GRB 170903A: Host galaxy redshift from OSIRIS/GTC
- GRB 170903A: Swift detection of a burst
- LIGO/Virgo G297595: DECam observations of BBH merger region of interest
- GRB 170902A: Swift detection of a burst or possible Galactic transient
- LIGO/Virgo G298048: Continued X-ray monitoring and X-ray detection of GW170817 [erratum]]
- LIGO/Virgo G298048: AGILE-GRID analysis of data contemporary to X-ray emission from SSS17a in NGC4993
- GRB 170831A: Fermi GBM detection
- GRB 170830A: Astrosat CZTI detection
- LIGO/Virgo G298048: GMRT Follow-up of SSS17a at 1.4 GHz
- Konus-Wind observation of GRB 170826B
- LIGO/Virgo G299232: GRAWITA Campo Imperatore optical observations
- LIGO/Virgo G298048: Discovery of X-ray emission from SSS17a in NGC4993
- GRB 170830A: MAXI/GSC detection
- LIGO/Virgo G298048: OVRO 40m telescope follow-up
- LIGO/Virgo G299232: WHT non-detection u-band optical transient
- IPN Triangulation of GRB 170826B
- LIGO/Virgo G299232/PGWB170825.55: early MASTER observations of the Swift UVOT source position
- GRB 170826B: Insight-HXMT detection
- GRB 170827A: Swift-XRT refined Analysis
- LIGO/Virgo G299232: OVRO-LWA simultaneous low frequency radio observations of localization region
- LIGO/Virgo G299232/PGWB170825.55: MASTER Global-Net OT inside NGC1343 discovery
- GRB 170827A: Swift detection of a burst
- GRB 170826B: Fermi GBM detection
- GRB 170826A: Fermi GBM detection
- LIGO/Virgo G299232: Nearby Galaxies in the Localization Volume
- GRB 170820A CALET Gamma-Ray Burst Monitor detection
- LIGO/Virgo G299232: Swift/BAT data search
- GRB 170822A: AstroSat CZTI detection
- LIGO/Virgo G299232: AGILE MCAL detection of a short gamma-ray candidate
- GRB 170825A: AGILE/MCAL Detection
- Konus-Wind observation of GRB 170822A
- LIGO/Virgo G298048: H.E.S.S. very-high energy gamma-ray follow-up
- LIGO/Virgo G297595: H.E.S.S. very-high energy gamma-ray follow-up
- GRB 170823A: Swift detection of a burst
- GRB 170822A: Swift detection of a burst
- LIGO/Virgo G298048: Pan-STARRS izy photometry of SSS17a/DLT17ck
- Konus-Wind observation of GRB 170816A
- GRB 170816A CALET Gamma-Ray Burst Monitor detection
- LIGO/Virgo G298048: Possible X-ray detection with Swift
- GRB 170817B: Insight-HXMT observation
- LIGO/Virgo G298048: Continued observation for DLT17ck
- LIGO/Virgo G298048: optical spectral energy distribution of SSS17a
- LIGO/Virgo G298048: Archival 2MASS and Spitzer non-detections of the potential LIGO EM counterpart SSS17a
- GRB 170818A: Fermi GBM detection
- LIGO/Virgo G298048: Archival VLA observations
- LIGO/Virgo G298048: ATCA detection of a radio source coincident with NGC 4993
- LIGO/Virgo G298048: REM optical/NIR observations
- LIGO/Virgo G298048: Pan-STARRS detections and izy photometry of the possible optical/NIR counterpart in NGC4993
- LIGO/Virgo G298048: Magellan g-band Imaging of the Potential Optical Counterpart Associated with NGC 4993
- LIGO/VIRGO G298048: Swift UVOT detection and XRT upper limits
- LIGO/Virgo G298048: VLA Detection
- LIGO/Virgo G298048: VISTA/VIRCAM detection of candidate counterpart
- GRB 170817B: Fermi GBM detection
- LIGO/Virgo G298048: Las Cumbres Observatory Detection of The Possible Optical Counterpart in NGC 4993
- LIGO/Virgo G298048: Nearby Galaxies in the Localization Volume using the updated sky map computed using LALInference
- LIGO/Virgo G298048: Nearby Galaxies in the Localization Volume with Face-on Assumption
- GRB 170817A: Fermi GBM detection
- LIGO/Virgo G298048: Nearby Galaxies in the Localization Volume
- LIGO/Virgo G298048: Insight-HXMT observations
- LIGO/Virgo G298048: INTEGRAL detection of a prompt gamma-ray counterpart