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.
Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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"- Swift GRB200909.97: Global MASTER-Net observations report
- GRB 200909B: Swift detection of a burst
- GRB 200909A: AstroSat CZTI detection
- GRB 200829A: T100 observations
- Fermi GRB 200909A: Global MASTER-Net observations report
- GRB 200909A: BALROG localization (Fermi Trigger 621316887 / GRB 200909168)
- GRB 200909A: Fermi GBM Final Real-time Localization
- GRB 200907B: Swift/UVOT Upper Limits
- Fermi GRB 200908A: Global MASTER-Net observations report
- GRB 200907B: Swift-BAT refined analysis
- Konus-Wind detection of GRB 200903E
- GRB 200908A: Fermi GBM Final Real-time Localization
- GRB 200907B: AstroSat CZTI detection
- GRB 200907B: Swift-XRT refined Analysis
- GRB 200907B: MITSuME Okayama optical upper limits
- Swift GRB 200907B: Global MASTER-Net observations report
- GRB 200907B: Enhanced Swift-XRT position
- Fermi GRB 200907C: Global MASTER-Net observations report
- GRB 200907C: Fermi GBM Final Real-time Localization
- Correction to GCN 28387: GRB 200907B GROWTH-India optical upper limit
- GRB200907A: GROWTH-India optical upper limit
- Fermi GRB 200906A: Global MASTER-Net observations report
- GRB 200907B: Prompt enhanced Swift-XRT position
- GRB 200907B: Swift detection of a short burst
- IPN triangulation of GRB 200903E
- GRB 200906A: EMIR/GTC NIR upper limit
- GRB 200906A: LBT near-infrared upper limit
- GRB 200906A: Swift-BAT refined analysis
- GRB 200906A: Swift/UVOT Upper Limits
- GRB 200907A: AGILE/MCAL detection of a burst
- GRB 200906A: GROWTH-India Telescope (GIT) optical r band upper limit
- GRB 200906A: OSN 1.5m Upper Limit
- GRB 200906A: Swift-XRT refined Analysis
- GRB 200906A: Fermi GBM detection
- GRB 200906A: Enhanced Swift-XRT position
- GRB 200906A: Nanshan/NEXT optical upper limit
- GRB 200906A: Swift detection of a burst
- GRB 200906A: Fermi GBM Final Real-time Localization
- Baksan Neutrino Observatory Alert 200905.99: Global MASTER-Net observations report
- Swift Triggers 994723-994725 and 994727 are not GRBs.
- GRB 200903E: AstroSat CZTI detection
- Fermi GRB 200904A: Global MASTER-Net observations report
- GRB 200904A: Fermi GBM Final Real-time Localization
- Fermi GRB 200903C: Global MASTER-Net observations report
- GRB 200903D: MAXI/GSC detection
- GRB 200903A: Fermi GBM detection
- GRB 200903C: Fermi GBM Final Real-time Localization
- GRB 200903A: Swift-BAT refined analysis
- GRB 200829A: optical observations, a light curve in R-filter
- GRB 200903B: Insight-HXMT/HE detection
- GRB 200903A: CALET Gamma-Ray Burst Monitor detection
- AGILE detection of a burst (AGILE trigger no. 526185273)
- ZTF20abtxwfx/AT2020sev : AstroSat CZTI non-detection of a transient
- GRB200817B: AstroSat CZTI detection
- Fermi GRB 200903B: Global MASTER-Net observations report
- GRB 200903B: Fermi GBM Final Real-time Localization
- Swift GRB200903.03: Global MASTER-Net observations report
- GRB 200903A: Swift detection of a burst
- GRB 200903A: Fermi GBM Final Real-time Localization
- GRB 200901A: MASTER OT early detection
- GRB 200901B: Swift-XRT refined Analysis
- INTEGRAL Weak#8699: AROMA-N Optical Observation
- GRB 200901B: Swift-BAT refined analysis
- GRB 200901A: Swift-BAT refined analysis
- GRB 200901B: Swift/UVOT Detection
- GRB 200901A: Swift/UVOT Detection
- GRB 200901A: Swift-XRT refined Analysis
- GRB 200901A: Fermi GBM observation
- GRB 200901B: Enhanced Swift-XRT position
- GRB 200829A: Swift/UVOT-XRT photometric redshift
- GRB 200901B: Swift detection of a burst
- GRB 200901A: Swift-XRT observations
- GRB 200901A: Swift detection of a burst
- Swift GRB200901.16: Global MASTER-Net observations report
- GRB 200829A: Koshka Zeiss-1000 optical observations
- Fermi GBM trigger 620564765/200831463 is not a GRB
- GRB 200829A: Liverpool Telescope observations
- GRB 200829A: Continued Nanshan/NEXT optical observations
- GRB 200829A: Kitab optical upper limit
- GRB 200829A: further SAO RAS optical observations
- Fermi GRB 200830A: Global MASTER-Net observations report
- GRB 200829A: Fermi GBM detection
- GRB 200829A: Swift-BAT refined analysis
- GRB 200829A: Nanshan/NEXT optical observations
- Konus-Wind detection of GRB 200829A (a clone of GRB 200826B?)
- GRB 200829A: SAO RAS optical observations
- GRB 200830A: BALROG localization (Fermi Trigger 620474063 / GRB 200830413)
- GRB 200830A: Fermi GBM Final Real-time Localization
- GRB 200826A
- GRB 200829A: THO optical observatios
- GRB 200829A: Swift-XRT refined Analysis
- GRB200829A: optical afterglow detection
- GRB 200829A: Global MASTER-Net OT detection
- GRB 200829A: AGILE/MCAL detection
- GRB 200829A: Enhanced Swift-XRT position
- GRB 200826A: Lowell Discovery Telescope observations of ZTF20abwysqy
- GRB 200829A: Swift/UVOT Detection
- Fermi trigger No 620402299: Global MASTER-Net observations report
- Swift GRB 200829A: Global MASTER-Net observations report
- GRB 200829A: TSHAO optical observations