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"6828 results found.
- GRB 200327A: Fermi GBM detection
- GRB 200325B: Fermi GBM observation
- GRB 200325B: Swift-XRT and UVOT observations
- GRB 200325A: Fermi GBM observation
- GRB 200324A: AROMA-N Optical Observation
- GRB 200324A: Swift-XRT refined Analysis
- GRB 200324A: NOT optical upper limit
- GRB 200323A: Fermi GBM detection
- Chandra observations of GW170817 at 2.5 years since merger (All epochs 4 of 4)
- GW170817: Continued X-ray emission detected with Chandra at 940 days post-merger
- LIGO/Virgo S200316bj: No counterpart candidates in Fermi-LAT observations
- LIGO/Virgo S200213t: Continued Swift UVOT and XRT observations of ZTF20aamvmzj (AT2020cja)
- LIGO/Virgo S200316bj: No counterpart candidates in INTEGRAL SPI-ACS, and IBIS prompt observation
- LIGO/Virgo S200316bj: upper limits from AGILE/MCAL observations
- GRB 200313A: Fermi GBM detection
- LIGO/Virgo S200311bg: No significant counterpart candidates in Fermi-LAT observations
- LIGO/Virgo S200311bg: No counterpart candidates in INTEGRAL SPI-ACS,prompt observation
- Chandra observations of GW170817 ~ 2.5 years since merger (epoch 1 of 4)
- GRB 200306C: Swift-XRT refined Analysis
- GRB 200306A: Swift-XRT refined Analysis
- GRB 200303A: Fermi GBM observation
- GRB 200303A: Swift-XRT refined Analysis
- LIGO/Virgo S200302c: No significant counterpart candidates in Fermi-LAT observations
- LIGO/Virgo S200302c: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- LIGO/Virgo S200302c: upper limits from AGILE/MCAL observations
- GRB 200228B: Swift-XRT refined Analysis
- GRB 200228B: Fermi GBM observation
- GRB 200228A: Fermi GBM observation
- LIGO/Virgo S200213t: No significant EM counterparts identified from continued GECKO observation of host galaxy candidates
- Fermi-LAT Gamma-ray Observations of IceCube-200227A
- GRB 200227A: Swift-XRT refined Analysis
- GRB 200227A: Fermi GBM observation
- IceCube-200227A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- LIGO/Virgo S200219ac: Upper limits from Konus-Wind observations
- LIGO/Virgo S200213t: Upper limits from Konus-Wind observations
- LIGO/Virgo S200208q: Upper limits from Konus-Wind observations
- LIGO/Virgo S200225q: No counterpart candidates in Fermi-LAT observations
- LIGO/Virgo S200225q: upper limits from AGILE/MCAL observations
- LIGO/Virgo S200224ca: No counterpart candidates in Fermi-LAT observations
- LIGO/Virgo S200225q: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- LIGO/Virgo S200224ca: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
- LIGO/Virgo S200224ca: upper limits from AGILE/MCAL observations
- GRB 200219C: Swift-XRT afterglow confirmation
- GRB 200224A: Swift-XRT refined Analysis
- GRB 200219C: OAJ afterglow confirmation
- GRB 200219C: Swift-XRT afterglow detection
- GRB 200219C: Fermi GBM detection
- LIGO/Virgo S200213t: Swift UVOT and XRT observations of ZTF20aamvmzj (AT2020cja)
- GRB 200219C: Fermi-LAT detection
- GRB 200219A, Swift-BAT refined analysis
- LIGO/Virgo S200219ac: No counterpart candidates in Fermi-LAT observations
- GRB 200219A: Swift-XRT refined Analysis correction
- GRB 200219A: Swift-XRT refined Analysis
- GRB 200219A: Fermi GBM observation
- LIGO/Virgo S200219ac: upper limits from AGILE/MCAL observations
- LIGO/Virgo S200219ac: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
- GRB 200216B: Swift-XRT refined Analysis
- Further Swift-XRT observations of Swift J0840.7-3516
- GRB 200215A: Swift-XRT refined Analysis
- GRB 200215A: Fermi GBM detection
- LIGO/Virgo S200213t: No candidates found in J-GEM follow-up observations
- LIGO/Virgo S200213t: No counterpart candidates in Fermi-LAT observations
- LIGO/Virgo S200213t: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
- ZTF20aajnksq: Upper limits from Konus-Wind observations
- LIGO/Virgo S200208q: No counterpart candidates in Fermi-LAT observations
- GRB 200120A: Fermi GBM observation
- LIGO/Virgo S200208q: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
- GRB 200205B: ESO/NTT near-infrared imaging
- GRB 200205B: Swift-XRT refined Analysis
- Swift GRB200205.81: Global MASTER-Net observations report
- Swift GRB200205.81: Global MASTER-Net OT detection
- LIGO/Virgo S200129m: Upper limits from Konus-Wind observations
- LIGO/Virgo S200128d: Upper limits from Konus-Wind observations
- GRB 200131A: Swift-XRT refined Analysis
- LIGO/Virgo S200129m: No counterpart candidates in Fermi-LAT observations
- LIGO/Virgo S200128d: upper limits from AGILE/GRID observations
- LIGO/Virgo S200129m: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
- LIGO/Virgo S200128d: No counterpart candidates in Fermi-LAT observations
- GRB 200127A: Swift/UVOT Upper Limits
- LIGO/Virgo S200128d: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
- GRB 200127A: Swift-XRT refined Analysis
- GRB 200125A: Swift-BAT refined analysis
- GRB 200125A: Further Swift-XRT observations
- GRB 200125B: Fermi GBM observations
- GRB 200125A: TNG detection of a NIR counterpart candidate
- Correction to GRB 200125A: Swift-XRT refined analysis
- GRB 200125A: Swift-XRT refined Analysis
- LIGO/Virgo S200115j: Zwicky Transient Facility search for optical counterparts to Swift X-ray sources
- LIGO/Virgo S200115j: Further Swift-XRT sources
- GRB 200122A: Swift-XRT refined Analysis
- Fermi-LAT Gamma-ray Observations of IceCube-200120A
- LIGO/Virgo S200115j: Upper limits from Konus-Wind observations
- LIGO/Virgo S200114f: Upper limits from Konus-Wind observations
- LIGO/Virgo S200112r: Upper limits from Konus-Wind observations
- GRB 191031D: XMM-Newton upper limit
- IceCube-200120A: no counterpart candidates in INTEGRAL SPI-ACS and,IBIS prompt observation
- LIGO/Virgo S200105ae: Upper limits from Konus-Wind observations
- LIGO/Virgo S191222n: Upper limits from Konus-Wind observations
- LIGO/Virgo S191216ap: Upper limits from Konus-Wind observations
- LIGO/Virgo S191215w: Upper limits from Konus-Wind observations