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"
3050 results found.
- GRB 160117A: Swift-XRT observations
- GRB 160117B: Swift-XRT refined Analysis
- LIGO/Virgo G211117: Further Swift-XRT sources
- GRB 160113A: Swift-XRT observations
- LIGO/Virgo G211117: Swift observations of PS15dpn
- LIGO/Virgo G211117: VISTA imaging
- LIGO/Virgo G211117: Further Swift-XRT sources
- GRB 160104A: Swift-XRT refined Analysis
- GRB 160104A: MITSuME Okayama Ks-band upper-limit
- GRB 160102A: Swift-XRT observations
- GRB 160101A: Swift/UVOT Detection
- GRB 160101A: Swift-XRT afterglow detection
- GRB 151228A: Correction to GCN 18770
- LIGO/Virgo G211117: SkyMapper observations and transient candidate
- GRB 151228A: Swift-XRT refined Analysis
- GRB 151229A: Swift-XRT refined Analysis
- GRB 151228B: Swift-XRT refined Analysis
- LIGO/Virgo G211117: Further Swift-XRT sources
- LIGO/Virgo G211117: Further Swift-XRT sources
- LIGO/Virgo G211117: Swift-XRT sources
- GRB 151215A: Swift-XRT refined Analysis
- GRB 151212A: Swift-XRT afterglow detection
- GRB 151210A: Swift-XRT refined Analysis
- GRB 151205B: further Swift-XRT observations
- GRB 151205C: Swift-XRT observations
- GRB 151205A: Swift-XRT refined Analysis
- GRB 151122A: Further Swift-XRT observations, no afterglow detected.
- GRB 151127A: Swift-XRT refined Analysis
- GRB 151122A: Swift-XRT observations
- Swift Trigger 664610 is not astrophysical
- GRB 151120A: Swift-XRT afterglow detection
- GRB 151118A: Swift-XRT refined Analysis
- GRB 151114A: Swift-XRT refined Analysis
- GRB 151112A: Swift-XRT refined Analysis
- GRB 151111A: Swift/UVOT upper limits
- GRB 151111A: Swift-XRT refined Analysis
- LIGO/Virgo G194575: Swift observations if iPTF15dld
- GRB 151031A: Swift-XRT refined Analysis
- GRB 151029A: Swift-XRT refined Analysis
- GRB 151027B: Swift-XRT refined Analysis
- GRB 151027A: Swift-XRT refined Analysis
- GRB 151023A: Swift-XRT refined Analysis
- GRB 151022A: Swift-XRT refined Analysis
- LIGO/Virgo G194575: Identification of a GW CBC Candidate
- GRB 151022A: MITSuME Okayama Ks-band upper-limit
- GRB 151021A: MITSuME Okayama Ks-band upper-limit
- GRB 151021A: Swift-XRT refined Analysis
- GRB 151004A: Swift-XRT follow-up observations
- GRB 151006A: MITSuME Okayama Ks-band upper-limit
- GRB 151006A: Swift-XRT refined Analysis
- Trigger 657564 / GRB 151004A: Swift BAT and XRT refined analysis
- Swift Trigger 657564: XRT prompt analysis
- GRB 151001B: Swift-XRT refined Analysis
- GRB 151001A: Swift-XRT refined Analysis
- GRB 150925A: Swift-XRT refined Analysis
- LIGO/Virgo G184098: SkyMapper observations
- LIGO/Virgo G184098: Swift follow-up observations
- GRB 150915A: Swift-XRT refined Analysis
- GRB150915A : IRSF NIR upper limits
- GRB 150907A: Swift-XRT afterglow detection
- GRB 150912A: Swift-XRT and UVOT observations
- GRB 150911A: Swift-XRT refined Analysis
- GRB150911A MITSuME Okayama Ks-band upper-limit
- GRB 150910A: MITSuME Okayama Ks-band Observation
- GRB 150910A: Swift-XRT refined Analysis
- GRB 150910A: Swift/UVOT Detection of a Brightening Afterglow
- GRB 150907B: Swift-XRT refined Analysis
- GRB 150907A: Swift-XRT observations
- GRB 150902A: Swift-XRT afterglow detection
- GRB 150902A: Swift-XRT observations
- GRB 150821A: Flattening in the UVOT light curve
- GRB 150831B: Swift-XRT refined Analysis
- GRB 150831A: Swift-XRT refined Analysis
- GRB 150821A: Swift-XRT refined Analysis
- GRB 150819A: Swift-XRT refined Analysis
- GRB 150818A: Swift-XRT update, correction to GCN 18162
- GRB 150818A: Swift-XRT refined Analysis
- GRB 150817A: Swift-XRT refined Analysis
- GRB 150811A: KAIT Refined Analysis
- GRB 150811A: Swift-XRT refined Analysis
- GRB 150727A: IRSF NIR observation
- GRB 150801A: Swift-XRT observations
- GRB 150801B: Swift-XRT refined Analysis
- GRB 150724B: Swift-XRT afterglow detection
- GRB 150728A: Swift-XRT refined Analysis
- GRB 150727A: Swift-XRT refined Analysis
- GRB 150724B: Swift-XRT observations
- Correction to GCN 18059: Parameterisation of Swift-XRT light curve
- GRB 150724A: Swift-XRT refined Analysis
- GRB 150722A: Swift-XRT refined Analysis
- GRB 150720A: Swift-XRT refined Analysis
- GRB 150716A: Swift-XRT refined Analysis
- GRB 150710B: Swift-XRT afterglow detection
- GRB 150710B: Swift-XRT and Swift-UVOT observations
- GRB 150711A: Swift-XRT refined Analysis
- Swift-XRT observations of GRB 150710A
- GRB 150702A: Swift-XRT observations
- GRB 150622A: Swift-XRT afterglow detection
- GRB 150627A: Swift-XRT afterglow detection
- GRB 150626B: Swift-XRT refined Analysis