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"5051 results found.
- GRB 160104A: MITSuME Akeno Optical Observation
- GRB 160104A: Swift detection of a burst
- LIGO/Virgo G211117: LOFAR follow-up
- LIGO/Virgo G211117: CSS/CRTS observations on 29/30 Dec 2015 UT
- GRB 160101A: MAXI/GSC detection
- LIGO/Virgo G211117: 44 transients from Pan-STARRS data during 2015-12-28/30
- IPN Triangulation of GRB 151227B
- V404Cyg Swift Trigger 668097: CrAO RT-22 radio observations
- LIGO/Virgo G211117: Optical Observations with Kiso Schmidt telescope and KWFC
- GRB 151229A Swift-BAT Spectral lag analysis
- GRB 151229A: Swift-XRT refined Analysis
- GRB 151228B: Swift-XRT refined Analysis
- LIGO/Virgo G211117: Further Swift-XRT sources
- LIGO/Virgo G211117: Swift-XRT sources
- Fermi GBM trigger 472694170/151224997 is not a GRB
- V404Cyg Swift Trigger 668097:
- GRB 151216A: MAXI/GSC detection
- GRB 151215A: Swift-XRT refined Analysis
- GRB151215A: P60 Optical Afterglow Candidate
- GRB 151210A: Swift-XRT refined Analysis
- Swift detection of 4U 1850-03
- GRB 130831A: MASTER early OT detection and LC
- GRB 151205A: Swift-XRT refined Analysis
- GRB 151205C: MAXI/GSC detection
- GRB 151205A: Garching Telescope Upper Limit
- GRB 151127A: Swift-XRT refined Analysis
- GRB 151120A: Swift-XRT afterglow detection
- GRB 151118A: Swift-XRT refined Analysis
- GRB GRB 151118A: MASTER-NET optical observations
- GRB 151114A: Swift-XRT refined Analysis
- GRB 151107B: CALET Gamma-Ray Burst Monitor detection
- GRB 151112A: GROND photometric redshift and i'-band prediction
- GRB 151112A: MAXI/GSC detection
- GRB 151112A: Swift-XRT refined Analysis
- GRB 151111A: Swift-XRT refined Analysis
- GRB 151107B: Mini-MegaTORTORA limits on simultaneous optical emission
- GRB 151107B
- LIGO/Virgo G194575: MAXI/GSC further analysis
- GRB 151031A: Swift-XRT refined Analysis
- LIGO/Virgo G194575: INAF-TNG follow-up of iPTF15dkm and iPTF15dlj
- GRB 151029A: Swift-XRT refined Analysis
- GRB 151029A: LCOGT-FTS afterglow observations
- GRB 151027B: Swift-XRT refined Analysis
- GRB 151027B: GROND Optical/NIR Afterglow Detection
- LIGO/Virgo G194575 : RATIR Observation of La Silla - QUEST Candidate
- GRB 151027A: MITSuME Akeno Optical observation
- GRB 151027A: Swift-XRT refined Analysis
- GRB 151027A: Swift detection of a burst with a bright optical afterglow
- LIGO/Virgo G194575: INAF-TNG follow-up of LSQ15bjb
- LIGO/Virgo G194575 : La Silla - QUEST followup
- LIGO/Virgo G194575: Near-infrared follow-up with OAO-WFC
- LIGO/Virgo G194575: Kanata/J-GEM optical follow-up
- GRB 151023A: Swift-XRT refined Analysis
- LIGO/Virgo G194575: CQUEAN/LOAO observations
- GRB 151022A: Swift-XRT refined Analysis
- LIGO/Virgo G194575: Mini-MegaTORTORA observations
- GRB 151021A: Swift-XRT refined Analysis
- GRB 151006A: MITSuME Akeno optical upper limits
- GRB 151006A: Swift-XRT refined Analysis
- LIGO/Virgo G184098: Further VST-ESO PARANAL observations
- Swift Trigger 657564: MASTER-NET early optical observations.
- GRB 151001B: Swift-XRT refined Analysis
- GRB 151001A: NOT imaging
- GRB 151001A: Swift-XRT refined Analysis
- LIGO/Virgo G184098: Liverpool Telescope Spectroscopy of PS15ccx
- GRB 150925A: Swift-XRT refined Analysis
- LIGO/Virgo G184098: optical transient search with Kiso Schmidt telescope and KWFC on behalf of J-GEM collaboration
- Konus-Wind observation of GRB 150919A
- ANTARES neutrino detection: Fermi GBM Observations
- LIGO/Virgo G184098: TAROT network optical observations
- LIGO/Virgo G184098: MWA Followup
- LIGO/Virgo G184098: VST-ESO PARANAL observations
- LIGO/Virgo G184098: TAROT La Silla Observatory optical observations (TZAC)
- GRB 150915A: Swift detection of a burst
- GRB 150911A: Swift-XRT refined Analysis
- GRB 150910A: Swift-XRT refined Analysis
- GRB 150907B: Swift-XRT refined Analysis
- Fermi GBM trigger 463339482/150907725 is too weak to be classified
- GRB 150906A: Fermi GBM detection
- ANTARES neutrino Alert150901.32 alert and Swift XRT counterpart: MASTER optical observations and new possible candidate
- GRB 150902A: MASTER-SAAO optical observations
- GRB 150831B: Swift-XRT refined Analysis
- GRB 150831B: MASTER-IAC early optical observations
- GRB 150831A: Swift-XRT refined Analysis
- INTEGRAL detection of GRB 150831A
- GRB 150824A: Fermi GBM detection
- GRB 150821A: Swift-XRT refined Analysis
- GRB 150819A: Swift-XRT refined Analysis
- GRB 150818A: Swift-XRT update, correction to GCN 18162
- GRB 150817A: AAO optical observations
- MASTER OT inside bright ESO240-010 galaxy detection during FERMI trigger GRB150816.83 inspection
- GRB 150817A: Swift-XRT refined Analysis
- GRB 150811A: Swift-XRT refined Analysis
- GRB 150801B: Swift-XRT refined Analysis
- GRB 150727A: Swift-XRT refined Analysis
- Konus-Wind observation of GRB 150725A
- GRB 150724B: Fermi GBM detection
- GRB 150724B: Fermi-LAT detection
- Swift IGR J00291+5934: MASTER Optical flare detection
- GRB 150724A: Swift-BAT refined analysis