GCN Circulars
GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"14950 results found.
- GRB 191023A: Fermi GBM Final Real-time Localization
- GRB 191019B: AstroSat CZTI detection
- GRB 191022B: Fermi GBM Final Real-time Localization
- GRB 191022A: Fermi GBM Final Real-time Localization
- Swift GRB191020.89: Global MASTER-Net OT detection
- GRB 191019A: Swift/UVOT Detection
- HAWC-191019A: No Neutrino Counterpart detected with ANTARES
- Swift GRB191020.81: Global MASTER-Net OT detection
- GRB 191019B: Fermi GBM Final Real-time Localization
- GRB 191019A: NOT optical observations
- GRB 191019A: Swift detection of a burst
- GRB 191016A: Swift-XRT afterglow detection
- GRB 191016A: Swift/UVOT Detection
- GRB 191017C: Fermi GBM Final Real-time Localization
- GRB 191017B: Swift detection of a burst
- GRB 191017A: Fermi GBM Final Localization
- GRB 191016A: AZT-20 (Assy observatory) optical photometry
- GRB 191016A: early time BOOTES Network and follow-up 1.5m OSN optical observations
- GRB 191016A: Optical limit by Ondrejov D50
- GRB 191016A: COATLI Optical Observations and Detection of the Afterglow
- GRB 191016A: Swift detection of a burst
- GRB 191009A: AstroSat CZTI detection
- GRB 191011A: Swift/UVOT Detection
- GRB 19011A: Optical Afterglow Detection with LCO
- GRB 191009A: Insight-HXMT/HE detection
- GRB 191011A: GROND Detection of the Optical/NIR afterglow
- GRB 191011A: VLT X-shooter redshift from RRM Observations
- Swift GRB191011.19: Global MASTER-Net OT detection
- GRB 191011A: Swift detection of a burst with an optical counterpart
- GRB 191011A: Fermi GBM Final Real-time Localization
- GRB 191009A: Fermi GBM Final Real-time Localization
- TESS Detection of the Optical Emission from the Possible Untriggered GRB Associated with ZTF19abvizsw
- GRB 191004A: CALET Gamma-Ray Burst Monitor detection
- GRB 191008A: Fermi GBM Final Real-time Localization
- GRB 191004B: Swift/UVOT Detection
- Konus-Wind observation of GRB 191004B
- Konus-Wind observation of GRB 191004A
- GRB 191004A: Swift/UVOT Detection
- GRB 191004A: Optical Detection with LCO
- GRB 190928A: AstroSat CZTI detection
- GRB 191004B: GROND Detection of the Optical/NIR Afterglow
- GRB 191004B: Optical Afterglow Detection with LCO
- Swift GRB191004.9: Global MASTER-Net OT detection
- GRB 191004B: Swift detection of a burst with an optical counterpart
- FACT follow-up of IceCube-191001A
- GRB 191004A: Swift detection of a burst with an optical detection
- Swift GRB191004.75: Global MASTER-Net OT detection
- LIGO/Virgo S190930t: AT2019rpn, AT2019rpj CrAO continued optical photometry
- GRB 190926A: Upper limit from CAHA 2.2m observation
- IceCube-191001A: HAWC follow-up
- GRB 190919A: AstroSat CZTI detection
- LIGO/Virgo S190930t: Upper limits from Insight-HXMT/HE observations
- LIGO/Virgo S190930s: Upper limits from Insight-HXMT/HE observations
- IPN triangulation of GRB 191001A
- GRB 191001A: KAIT Optical Upper Limit
- GRB 191001A: RATIR Optical and NIR Observations
- IceCube-191001A - IceCube observation of a high-energy neutrino candidate event
- LIGO/Virgo S190930t: Upper limits on the two of the ZTF/GROWTH candidates
- LIGO/Virgo S190923y: optical spectrum of MASTER detected transient
- GRB 191001B: Swift detection of a burst
- LIGO/Virgo S190930t: Transient found in Swift/UVOT counterpart search
- LIGO/Virgo S190930t and S190930s: MASTER PSN in unknown disk galaxy
- LIGO/Virgo S190930t: Candidates from the Zwicky Transient Facility
- LIGO/Virgo S190930t and S190930s: MASTER optical observation and optical transient
- GRB 191001A: Fermi GBM Final Real-time Localization
- LIGO/Virgo S190930t: Upper limits from Fermi-GBM Observations
- LIGO/Virgo S190930s: Upper limits from Fermi-GBM Observations
- LIGO/Virgo S190930t: No counterpart candidates in HAWC observations
- GRB 190928A: Insight-HXMT/HE detection
- Konus-Wind observation of GRB 190928A
- GRB 190928A: MASTER optical observations
- GRB 190930A: Fermi GBM Final Real-time Localization
- GRB 190928A: CALET Gamma-Ray Burst Monitor detection
- GRB 190926A: AbAO upper optical limit
- GRB 190928A: AGILE/MCAL detection of a burst
- GRB 190926A: Upper Limit from OSN T150 Observation
- LIGO/Virgo S190923y: MASTER OT outburst detection inside NSBH merger error-box
- GRB 190926A: Swift detection of a burst
- LIGO/Virgo S190924h: Upper limits from Fermi-GBM Observations
- IceCube-190922B - HAWC follow-up
- LIGO/Virgo S190923y: Upper limits from Fermi-GBM Observations
- LIGO/Virgo S190814bv: Chandra X-ray non-detection of ASKAP J005547-270433 / AT2019osy
- GRB 190923A: Fermi GBM Final Real-time Localization
- LIGO/Virgo S190923y: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
- LIGO/Virgo S190923y: No counterpart candidates in HAWC observations
- IceCube-190922B - IceCube observation of a high-energy neutrino candidate event
- IceCube-190922A - IceCube observation of a high-energy neutrino candidate event
- GRB 190921A: Fermi GBM Final Real-time Localization
- GRB 190919B: LCO Optical Afterglow Detection
- GRB 190919B: FRAM-Auger optical detection
- GRB 190919B: MASTER OT early detection at GROND position
- GRB 190919B: GROND detection of the NIR afterglow
- GRB 190919A: Fermi GBM Final Real-time Localization
- HAWC-190916A: Upper limits from Insight-HXMT/HE observations
- GRB 190828B: AstroSat CZTI detection
- LIGO/Virgo S190915ak: Upper limits from Fermi-GBM Observations
- GRB 190916A: Fermi GBM Final Real-time Localization
- GRB 190915A: Insight-HXMT/HE detection
- GRB 190915A: Fermi GBM Final Real-time Localization
- LIGO/Virgo S190814bv: No counterpart candidate after completion of GRAWITA VST-ESO PARANAL transient survey.