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"7447 results found.
- LIGO/Virgo S190814bv: Prioritization of Counterpart Candidates based on a Photometric Redshift Analysis by the DECam-GROWTH Team
- LIGO/Virgo S190814bv: Not observable by CALET
- LIGO/Virgo S190814bv: Pan-STARRS imaging indicates DG19sevhc (AT2019npy) is a proper motion star
- LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of desgw-190814e, DG19sevhc and selected galaxies
- LIGO/Virgo S190814bv: No additional candidates from the Zwicky Transient Facility
- LIGO/Virgo S190814bv: SOAR spectroscopy of 2 DESGW candidates
- LIGO/Virgo S190814bv: no candidates from optical imaging of selected galaxies at the NOT
- LIGO/Virgo S190814bv: No candidates from DCT galaxy targeted search and observations of DECam-GROWTH candidates
- LIGO/Virgo S190814bv: New candidates from DECam DESGW difference imaging search
- LIGO/Virgo S190814bv: GROND imaging of candidate galaxies
- S190814bv: MASTER analysis of DECam-GROWTH candidates
- LIGO/Virgo S190816i: Retraction of GW compact binary merger candidate
- LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of selected galaxies
- LIGO/Virgo S190814bv: No candidates identified in DECam data by visual inspection
- LIGO/Virgo S190814bv: des-gw190814b is a moving object
- LIGO/Virgo S190814bv: ATLAS forced photometry non-detections of DESGW candidates
- LIGO/Virgo S190814bv: No candidates from the Zwicky Transient Facility
- LIGO/Virgo S190814bv: KMTNet observation
- LIGO/Virgo S190814bv : No counterpart candidate in TAROT-GRANDMA observations
- LIGO/Virgo S190814bv: Candidates found in initial DESGW search
- LIGO/Virgo S190814bv: Upper limits from AGILE-GRID observations
- LIGO/Virgo S190814bv: Update on Sky-Localization and Source-Classification
- LIGO/Virgo S190814bv: no candidates from WHT imaging of candidate galaxies
- LIGO/Virgo S190814bv: GRAWITA TNG imaging of selected galaxies
- LIGO/Virgo S190814bv : no neutrino counterpart candidate in ANTARES search
- LIGO/Virgo S190814bv: Upper limits from Fermi-GBM Observations
- LIGO/Virgo S190814bv: Nordic Optical Telescope imaging of selected galaxies
- LIGO/Virgo S190814bv: Identification of a GW compact binary merger candidate
- LIGO/Virgo S190814bv: Upper limits from IceCube neutrino searches
- LIGO/Virgo S190814bv: CLU/NED Galaxies in the 50% Localization Volume
- HAWC-190806A: Swift-XRT observations
- Trigger_11505: Tiled Swift observations
- LIGO/Virgo S190728q: New optical candidates from the DESGW program
- LIGO/Virgo S190808ae: Retraction of GW compact binary merger candidate
- LIGO/Virgo S190808ae: CLU/NED Galaxies in the 50% Localization Volume
- LIGO/Virgo S190808ae: No counterpart candidates in HAWC observations
- LIGO/Virgo S190808ae: One Coincident Neutrino Candidate from IceCube Search
- LIGO/Virgo S190808ae: Identification of a GW compact binary merger candidate
- GRB 190805B: Tiled Swift observations
- GRB 190804B: Tiled Swift observations
- IceCube 190730A: No counterpart candidates or blazar activity in GOTO observations
- GRB 190719C: VLT/X-shooter spectroscopic redshift of the host galaxy
- LIGO/Virgo S190727h: Updated sky localization
- GRB 190731A: Swift ToO observations
- LIGO/Virgo S190728q: ZTF Forced Photometry for PS1 and DECam-GROWTH optical candidates, and a note on DECam Photometry from GCN 25215
- IceCube 190730A: not observable by Fermi-GBM
- LIGO/Virgo S190707q: AstroSat CZTI upper limits
- LIGO/Virgo S190718y: AstroSat CZTI upper limits
- LIGO/Virgo S190727h: AstroSat CZTI upper limits
- LIGO/Virgo S190720a: AstroSat CZTI upper limits
- IceCube-190730A - IceCube observation of a high-energy neutrino candidate event
- LIGO/Virgo S190727h: Gaia Photometric Alerts transient candidate
- LIGO/Virgo S190728q/IceCube neutrino candidate: No counterpart candidates in the Swift-XRT Observations
- LIGO/VIRGO S190728q: No candidate counterparts from ATLAS observations
- LIGO/Virgo S190728q: Third update on neutrino search with IceCube
- LIGO/Virgo S190728q: Update on Sky-Localization and Source-Classification
- LIGO/Virgo S190728q: ZTF19abjethn is inconsistent with new GW localization
- LIGO/Virgo S190728q: Identification of a Faint Blue Static Source at the Location of ZTF19abjethn
- LIGO/Virgo S190728q: Photometric Redshift and Stellar Mass Estimates for the Potential Host Galaxy of Optical Counterpart Candidate ZTF19abjethn
- LIGO/Virgo S190728q: Optical Candidate from the Zwicky Transient Facility ZTF19abjethn
- LIGO/Virgo S190728q: Second update on neutrino search with IceCube
- LIGO/Virgo S190728q: Upper limits from Fermi-GBM Observations
- LIGO/Virgo S190728q: no counterpart candidates in AGILE-GRID observations
- LIGO/Virgo S190728q : no neutrino counterpart candidate in ANTARES search
- LIGO/Virgo S190728q: One neutrino candidate from IceCube search
- LIGO/Virgo S190728q: No counterpart candidates in HAWC observations
- LIGO/Virgo S190728q: Identification of a GW compact binary merger candidate
- LIGO/Virgo S190728q: Upper limits from IceCube neutrino searches
- LIGO/Virgo S190727h: No counterpart candidates in the Swift/BAT Observations
- LIGO/Virgo S190727h: possible counterpart candidate in SPI-ACS/INTEGRAL
- LIGO/Virgo S190727h: Upper limits from Fermi-GBM Observations
- LIGO/Virgo S190727h: No counterpart candidates in HAWC observations
- LIGO/Virgo S190727h : no neutrino counterpart candidate in ANTARES search
- LIGO/Virgo S190727h: Identification of a GW compact binary merger candidate
- LIGO/Virgo S190727h: Upper limits from IceCube neutrino searches
- LIGO/Virgo S190718y: Gaia Photometric Alerts transient candidates
- LIGO/Virgo S190720a: Updated localization from LIGO and Virgo data
- LIGO/Virgo S190720a: Upper limits from CALET observations
- GRB 190719C: Swift/UVOT Upper Limits
- LIGO/Virgo S190720a: Upper limits from Fermi-GBM Observations
- LIGO/Virgo S190720a: Upper limits from AGILE-GRID observations
- LIGO/Virgo S190720a : no neutrino counterpart candidate in ANTARES search
- LIGO/Virgo S190720a: AGILE-MCAL observations
- LIGO/Virgo S190720a: Identification of a GW compact binary merger candidate
- LIGO/Virgo S190720a: No counterpart candidates in HAWC observations
- LIGO/Virgo S190720a: Upper limits from IceCube neutrino searches
- GRB 190719C: NOT candidate optical afterglow and host
- LIGO/Virgo S190718y: ZTF pre-detection of MASTER candidate AT2019lly
- LIGO/Virgo S190718y: Analysis update
- GRB 190719C: Swift detection of a burst
- LIGO/Virgo S190718y: Upper limits from Fermi-GBM Observations
- LIGO/Virgo S190630ag: Updated sky localization
- LIGO/Virgo S190718y : no neutrino counterpart candidate in ANTARES search
- LIGO/Virgo S190718y: Identification of a GW compact binary merger candidate
- LIGO/Virgo S190718y: Upper limits from IceCube neutrino searches
- GRB 190718A: Swift detection of a burst
- GRB 190714A: Tiled Swift observations
- IceCube-190712A: No neutrino counterpart candidates in ANTARES search
- IceCube-190712A: Upper limits from Fermi-GBM Observations
- IceCube-190712A - IceCube observation of a high-energy neutrino candidate event