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"11848 results found.
- IceCube-191001A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
- IceCube-191001A - IceCube observation of a high-energy neutrino candidate event
- LIGO/Virgo S190930s: No counterpart candidates in KAIT observations
- GRB 191001A: DDOTI Optical Counterpart Candidate
- IceCube Alert 191001.84: Global MASTER-Net observations report
- LIGO/Virgo S190814bv: VLA 6 GHz observations of 75 galaxies in the 90% localization region
- GRB 191001B: Swift detection of a burst
- LIGO/Virgo S190930t: No counterpart candidates in Fermi-LAT observations
- LIGO/Virgo S190930s: No counterpart candidates in Fermi-LAT observations
- LIGO/Virgo S190930s: Upper limits from CALET observations.
- LIGO/Virgo S190930t: Coverage and upper limits from MAXI/GSC observations
- LIGO/Virgo S190930t: No counterpart candidates in HAWC observations
- LIGO/Virgo S190930s: Coverage and upper limits from MAXI/GSC observations
- Fermi trigger No 591532362: Global MASTER-Net observations report
- Konus-Wind observation of GRB 190928A
- Fermi trigger No 591391412: Global MASTER-Net observations report
- GRB 190928A: AGILE/MCAL detection of a burst
- GRB 190926A: Swift-XRT refined Analysis
- LIGO/Virgo S190923y: No significant candidates in TAROT-GRANDMA observations
- LIGO/Virgo S190924h: No counterpart candidates in Fermi-LAT observations
- Fermi-LAT Gamma-ray Observations of IceCube-190922B
- LIGO/Virgo S190924h: Coverage and upper limits from MAXI/GSC observations
- LIGO/Virgo S190923y: No counterpart candidates in Fermi-LAT observations
- Fermi-LAT Gamma-ray Observations of IceCube-190922A
- LIGO/Virgo S190923y: Coverage and upper limits from MAXI/GSC observations
- LIGO/Virgo S190923y: No counterpart candidates in HAWC observations
- IceCube Alert 190922.96: Global MASTER-Net observations report
- IceCube-190922A - IceCube observation of a high-energy neutrino candidate event
- Baksan Neutrino Observatory Alert 190920.65: Global MASTER-Net observations report
- GRB 190919B: LCO Optical Afterglow Detection
- GRB 190919B: FRAM-Auger optical detection
- GRB 190919B: Swift-XRT observations
- GRB 190919B: A long GRB detected by INTEGRAL
- Integral GRB190919.99: Global MASTER-Net observations report
- Fermi trigger No 590621700: Global MASTER-Net observations report
- GRB 190919A: Fermi GBM Final Real-time Localization
- LIGO/Virgo S190915ak: No significant candidates in TAROT-GRANDMA observations
- LIGO/Virgo S190910h: No significant candidates in TAROT-GRANDMA observations
- LIGO/Virgo S190915ak: No counterpart candidates in Fermi-LAT observations
- LIGO/Virgo S190915ak: Coverage and upper limits from MAXI/GSC observations
- LIGO/Virgo S190915ak: Global MASTER-Net observations report
- LIGO/Virgo S190910d : No significant candidates in TAROT-GRANDMA observations
- Fermi trigger No 590038994: Global MASTER-Net observations report
- LIGO/Virgo S190910h: No counterpart candidates in Fermi-LAT observations
- LIGO/Virgo S190910h: Gaia Photometric Alerts transient candidates
- LIGO/Virgo S190910d and S190910h: No counterpart candidates in KAIT observations
- LIGO/Virgo S190910d: AT2019pvu, AT2019pvv, AT2019pvz and AT2019pwa 10.4m GTC spectroscopy
- LIGO/Virgo S190910d: Liverpool Telescope spectroscopy of ZTF19abyfazm
- LIGO/Virgo S190910d: AstroSat CZTI upper limits
- LIGO/Virgo S190910d: No counterpart candidates in Fermi-LAT observations
- LIGO/Virgo S190910h: No counterpart candidates in HAWC observations
- LIGO/Virgo S190910h Global MASTER-Net observations report
- LIGO/Virgo S190910h: Coverage and upper limits from MAXI/GSC observations
- LIGO/Virgo S190910d: Coverage and upper limits from MAXI/GSC observations
- LIGO/Virgo S190910d: No counterpart candidates in HAWC observations
- LIGO/Virgo S190901ap : No significant candidates found in GRANDMA citizen science observations
- ZTF19abvizsw: AbAO and CrAO photometry
- LIGO/Virgo S190814bv: GRAWITA VST-ESO PARANAL observations and independent transient candidates discovery.
- LIGO/Virgo S190901ap : No significant candidates in TAROT-GRANDMA
- LIGO/Virgo S190901ap: No counterpart candidates in KAIT observations
- Konus-Wind observation of GRB 190829A
- Swift XRT Detection of X-ray Emission from ZTF19abvizsw
- LIGO/Virgo S190901ap: GOTO optical coverage and detection of AT2019pjv
- LIGO/Virgo S190901ap: GTC follow-up spectroscopic observations of ZTF19abvizsw
- LIGO/Virgo S190901ap : GRAWITA photometric observation of candidate ZTFabvizsw and GCN 25618 revision
- LIGO/Virgo S190901ap: no counterpart candidate in the SVOM/GWAC observations
- Liverpool Telescope observations of ZTF19abvizsw, a candidate untriggered GRB afterglow
- LIGO/Virgo S190901ap: Upper limits from AGILE-GRID observations
- LIGO/Virgo S190828l: no counterpart candidate in the SVOM/GWAC observations
- LIGO/Virgo S190828j: no counterpart candidate in the SVOM/GWAC observations
- LIGO/Virgo S190901ap: No counterpart candidates in Fermi-LAT observations
- LIGO/Virgo S190901ap: Coverage and upper limits from MAXI/GSC observations
- LIGO/Virgo S190901ap: No counterpart candidates in HAWC observations
- Fermi trigger No 589060361 Global MASTER-Net observations report
- GRB 190829A: Keck LRIS spectroscopy of the optical afterglow
- LIGO/Virgo S190828j : No significant candidates in TAROT-GRANDMA observations
- LIGO/Virgo S190828l: No significant candidates in TAROT-GRANDMA observations
- GRB 190829A: Follow up VLA and VLBI radio observations urged
- GRB 190829A, Swift-BAT refined analysis
- GRB 190829A: Fermi GBM detection
- GRB 190829A: Fermi-LAT Upper Limits
- GRB 190829A:: Global MASTER-net optical clear and polarization observations scheduler and some spiculations
- GRB 190829A: Swift-XRT refined Analysis
- GRB 190830B: Fermi GBM Final Real-time Localization
- LIGO/Virgo S190828l: No counterpart candidates in KAIT observations
- GRB 190829A:: MASTER-net bright and decay OT detection
- GRB 190829A: Dabancheng-0.5m optical afterglow detection
- Fermi trigger No 588801358 Global MASTER-Net observations report
- GRB 190828B: Swift-XRT refined Analysis
- LIGO/Virgo S190814bv: VLA observation of ASKAP J005547-270433/AT2019osy
- LIGO/Virgo S190828l: No counterpart candidates in Fermi-LAT observations
- LIGO/Virgo S190828j: No counterpart candidates in KAIT observations
- LIGO/Virgo S190828j: No counterpart candidates in Fermi-LAT observations
- GRB 190828D: A long GRB detected by INTEGRAL
- Integral GRB190828.78 Global MASTER-Net observations report
- GRB 190828B: Swift detection of a burst
- LIGO/Virgo S190828l: Coverage and upper limits from MAXI/GSC observations
- LIGO/Virgo S190828j: Coverage and upper limits from MAXI/GSC observations
- LIGO/Virgo S190828l: No counterpart candidates in HAWC observations
- LIGO/Virgo S190828j: No counterpart candidates in HAWC observations