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"11756 results found.
- GRB 151228A: T60 observations
- GRB 151229A: Swift detection of a short burst
- LIGO/Virgo G211117: Optical NIR observation with Kanata telescope
- LIGO/Virgo G211117: Optical follow-up with Kanata telescope
- GRB 151228B: Swift detection of a burst with an optical detection
- LIGO/Virgo G211117: MASTER Observations and Inspection + OT
- LIGO/Virgo G211117: INTEGRAL was inactive at the time of the event
- LIGO/Virgo G211117: Pan-STARRS1 observations 2015-12-28
- GRB 151212A iTelescope observation
- Konus-Wind observation of GRB 151222A
- V404Cyg Swift Trigger 668097: MASTER-Tunka optical wake up detection
- V404Cyg Swift Trigger 668097:
- Fermi GBM trigger 472271765/151220108 is not a GRB
- GRB 151221A: INTEGRAL detection of a short burst or possible SGR
- LIGO/Virgo G184098: Fermi-LAT search for high-energy gamma-ray counterpart
- GRB 151212B: CALET Gamma-Ray Burst Monitor detection
- GRB 151216A: MAXI/GSC detection
- GRB 151210B: CALET Gamma-Ray Burst Monitor detection
- GRB 151212A: MAXI/GSC detection
- GRB 151210A: GROND Afterglow Confirmation
- GRB 151210A: Optical afterglow candidate from LCOGT-Cerro Tololo
- GRB 151205C: Optical follow-up observations at Kiso
- GRB 151205A: Khureltogot upper limit
- GRB 130831A: MASTER early OT detection and LC
- GRB 151205A: Swift-XRT refined Analysis
- GRB 151205C: MAXI/GSC detection
- GRB 151205B: MASTER-NET early optical observations
- GRB 151205A: Swift detection of a burst
- GRB 151127A iTelescope observation
- GRB 151127A: LCOGT-SSO optical upper limits
- GRB 151118A iTelescope observation
- Konus-Wind observation of GRB 151120A
- GRB 151120A: Swift-XRT afterglow detection
- GRB 151120A: Fermi GBM observation
- GRB 151120A: GROND optical/NIR afterglow
- GRB 151120A: A long GRB detected by INTEGRAL
- 610 MHz detection of GRB 151027A with the GMRT
- GRB GRB 151118A: MASTER-NET optical observations
- GRB151027A; Optical observations
- GMRT radio detection of GRB 151027A
- GRB 151107B: CALET Gamma-Ray Burst Monitor detection
- GRB 151114A: Swift detection of a burst with an optical counterpart
- GRB 151112A: MAXI/GSC detection
- GRB 151112A: Swift-XRT refined Analysis
- GRB 151112A: Swift-BAT refined analysis
- GRB 151112A: Swift-XRT observations
- GRB 151112A: Swift detection of a burst
- GRB 151111A: Swift-XRT refined Analysis
- GRB 151111A: Swift detection of a burst
- GRB 151107B: MASTER-NET OT detection inside the FERMI error box
- GRB 151107B: Mini-MegaTORTORA limits on simultaneous optical emission
- GRB 151107B
- GRB 151107A: MASTER-NET optical observations
- GRB 150910A: CrAO optical observations
- LIGO/Virgo G194575: LT Spectroscopy of iPTF candidates
- GRB 151031A: Swift-XRT refined Analysis
- GRB 151031A: Swift detection of a burst
- LIGO/Virgo G194575: INAF-TNG follow-up of iPTF15dkm and iPTF15dlj
- GRB 151027A: Optical counterpart detection
- GRB 151029A: Swift-XRT refined Analysis
- GRB 151029A: Swift detection of a burst with an optical counterpart
- GRB 151027A: SAO RAS optical observations
- GRB 151027A: NOT optical and NIR observations
- Konus-Wind observation of GRB 151027A
- GRB 151027A: LCOGT-McDonald afterglow observations
- GRB 151027B: Swift-XRT refined Analysis
- GRB 151027B: Swift detection of its 1000-th burst
- LIGO/Virgo G194575: iPTF Optical Transient Candidates
- LIGO/Virgo G194575: MASTER Optical Inspection
- GRB 151027A: Swift-XRT refined Analysis
- LIGO/Virgo G194575: Swift observations of LSQ15bjb
- Tentative redshift for GRB 151027A from Swift-XRT data
- GRB 151027A: P60 afterglow confirmation and rebrightening
- GRB 151027A: KAIT optical afterglow confirmation
- GRB 151006A: CALET Gamma-Ray Burst Monitor detection
- LIGO/Virgo G194575: Near-infrared follow-up with OAO-WFC
- LIGO/Virgo G194575: Kanata/J-GEM optical follow-up
- LIGO/Virgo G194575: CQUEAN/LOAO observations
- Possible Fermi-LAT Gamma-ray counterpart for LIGO/Virgo G194575
- LIGO Virgo G194575: MWA Observations
- LIGO/Virgo G194575: INTEGRAL search of temporally coincident prompt hard X-ray emission
- LIGO/Virgo G194575: more details on transients from Pan-STARRS in the RA=1hr localisation region
- GRB 151022A: MITSuME Okayama upper limits
- GRB 151022A: Swift detection of a burst
- Konus-Wind observation of GRB 151021A
- GRB 151021A: Swift-XRT refined Analysis
- GRB 151021A: Swift detection of a burst
- LIGO/Virgo G184098: VLA follow-up of iPTF15cyk
- GRB 151006A: MITSuME Akeno optical upper limits
- Konus-Wind observation of GRB 151006A
- GRB 151006A: Swift-XRT refined Analysis
- GRB 151006A: Fermi-LAT detection
- Konus-Wind observation of GRB 151001B
- LIGO/Virgo G184098: Further VST-ESO PARANAL observations
- Trigger 657564 / GRB 151004A: Swift/UVOT Upper Limits
- LIGO/Virgo G184098: MASTER OTs detection and Scenario Machine prediction
- GRB 151001A: Swift/UVOT Detection
- GRB 151001B: MASTER-NET early optical observations.
- GRB 151001A: NOT imaging
- GRB 151001A: Swift-XRT refined Analysis