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.
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"2983 results found.
- GRB 160625B: MITSuME Ishigakijima Optical Observation
- Swift-BAT refined analysis on the bright event from SGR 1935+2154
- IPN Triangulation of GRB 160620A (short/hard)
- GRB 160625A: Swift-BAT refined analysis
- Swift-BAT refined analysis of the recent outburst from SGR 1617-5103 (a.k.a. 1E 161348-5055 and 2E 1613.5-5053)
- IPN Triangulation of GRB 160612A (short/hard)
- GRB160611.9 MASTER-Net OT detection
- GRB 160607A: Swift-BAT refined analysis
- Fermi GBM trigger 486907024/160606498 is not a GRB
- GRB 160601A: MITSuME Okayama Ks-band upper-limit
- GRB 160525B: Prompt enhanced Swift-XRT position
- GRB 160509A: MAXI/GSC refined analysis
- GRB 160501A: Swift-BAT refined analysis
- GRB 160501A: NOT optical and NIR observations
- GRB 160425A: Swift-BAT refined analysis
- GRB 160422A: Swift/UVOT Afterglow Confirmation
- Konus-Wind observation of GRB 160424A
- GRB 160422A: Swift-XRT afterglow detection
- GRB 160422A: Swift/UVOT Candidate Afterglow
- GRB 160419A, Swift-BAT refined analysis
- LIGO/Virgo G211117: EWE for NOWT of 12 days follow-up of northern sky
- GRB 160401A: Zadko observatory - Gingin optical observations
- GRB 160401A: MASTER-IAC prompt optical observations
- LIGO/Virgo G211117: LOFAR follow-up
- Konus-Wind observation of GRB 160325A
- GRB 160321A: Swift detection of a probable burst
- GRB 160313A: Mondy optical upper limit
- Konus-Wind observation of GRB 160310A (possible ultra-long GRB?)
- GRB 160310A: NOT optical observations
- GRB 160310A: LCOGT-SAAO optical upper limits
- GRB 160303A: MITSuME Okayama upper limits
- GRB 160227B: Fermi GBM detection
- GRB 160228A: Swift detection of a burst
- GRB 160227A, Swift-BAT refined analysis
- GRB 160225A: WHT LIRIS observations
- Konus-Wind observation of GRB 160220B
- GRB 160220B: Swift-BAT refined analysis
- LIGO/Virgo G211117: LOFAR follow-up
- GRB 160131A: AbAO optical observations
- GRB 160131A: Khureltogot optical observations
- GRB160131.35 MASTER-Net OT detection
- GRB 160127A: Swift-BAT refined analysis
- LIGO/Virgo G211117: Further Swift-XRT sources
- LIGO/Virgo G211117: Subaru Hyper Suprime-Cam follow-up observation
- GRB 160107A: MAXI/GSC detection
- LIGO/Virgo G211117: Summary of Pan-STARRS transients
- GRB 160104B: MAXI/GSC detection
- LIGO/Virgo G211117: LOFAR follow-up
- LIGO/Virgo G211117: PESSTO classification of Pan-STARRS transients
- GRB 160101A: MAXI/GSC detection
- LIGO/Virgo G211117: LBT follow-up imaging of iPTF15fhq
- LIGO/Virgo G211117: 44 transients from Pan-STARRS data during 2015-12-28/30
- GRB 151228B: Swift/UVOT Detection
- LIGO/Virgo G211117: Optical Observations with Kiso Schmidt telescope and KWFC
- LIGO/Virgo G211117: iPTF Optical Transient Candidates
- GRB 151228B: Swift-BAT refined analysis
- LIGO/Virgo G211117: Optical follow-up with Kanata telescope
- GRB 151228B: Swift detection of a burst with an optical detection
- LIGO/Virgo G211117: INTEGRAL was inactive at the time of the event
- GRB 151212A: GROND Optical Afterglow Candidate
- GRB 151212A: Swift-XRT afterglow detection
- GRB 151210A: Swift-BAT refined analysis
- GRB 130831A: MASTER early OT detection and LC
- GRB 151205A: Garching Telescope Upper Limit
- GRB 151111A: Swift-BAT refined analysis
- GRB 151031A: Swift detection of a burst
- LIGO/Virgo G194575: INAF-TNG follow-up of iPTF15dkm and iPTF15dlj
- GRB 151029A: Swift-BAT refined analysis
- GRB 151027A: SAO RAS optical observations
- LIGO/Virgo G194575: Near-infrared follow-up with OAO-WFC
- LIGO/Virgo G194575: Kanata/J-GEM optical follow-up
- GRB 151021B: Fermi GBM detection
- LIGO/Virgo G184098: Further VST-ESO PARANAL observations
- Trigger 657564 / GRB 151004A: Swift BAT and XRT refined analysis
- LIGO/Virgo G184098: ongoing Pan-STARRS search for optical transients
- LIGO/Virgo G184098: ongoing Pan-STARRS search for optical transients
- IPN Triangulation of GRB 150922A (short/hard)
- LIGO/Virgo G184098: VST-ESO PARANAL observations
- GRB 150911A: Swift-BAT refined analysis
- GRB 150911A: MITSuME Okayama upper limits
- IPN Triangulation of GRB 150906B (short/intense)
- GRB 150907B: Swift-BAT refined analysis
- GRB 150831B: MASTER-IAC early optical observations
- GRB 150831A: Swift detection of a short burst
- IPN Triangulation of GRB 150824A
- GRB 150819A: Mondy and TSHAO optical upper limits
- GRB 150821A: Fermi GBM detection
- GRB 150821A: Swift detection of a burst with an optical afterglow
- Konus-Wind observation of GRB 150819B
- GBM Trigger 150813665 is not a GRB
- GRB 150728A: FTN observations
- GRB 150724B: MASTER upper limit
- GRB 150722A: Swift detection of a burst
- Fermi Gamma-ray Burst Monitor triggers that are not GRBs
- GRB 150710B refined analysis
- GRB 150710B detected in ground analysis of BAT data
- Swift-XRT observations of GRB 150710A
- GRB 150702A: MASTER-SAAO inspection
- GRB 150702A: Swift-XRT observations
- GRB 150627A: MASTER-SAAO OT Detection