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"5544 results found.
- GRB 160910A: Mondy optical observations
- GRB 160910A: Global MASTER Net OT detection before LAT alert
- GRB 160912A: Swift detection of a burst
- IceCube HESE 160814: MASTER OT J130845.02-323254.9 as the possible source of the high energy neutrino
- GRB 160905A: Swift detection of a burst with an optical counterpart
- GRB 160827A: Swift detection of a burst
- GRB 160825A: not localized by Swift
- IPN Triangulation of GRB 160820A (short/hard)
- GRB 160821B: Swift detection of a short burst
- GRB 160814A: MAXI/GSC detection
- Swift Trigger 707545 is likely 4U 1850-03/GS1843-02
- GRB160804A: MASTER-SAAO observation
- IPN Triangulation of GRB 160802A
- GRB 160804A: Swift/UVOT Detection
- GRB 160801A: SAO RAS optical observations
- GRB 160801A: Swift detection of a burst
- GRB 160716A: Swift detection of a burst
- GRB 160709A: MASTER early imaging Swift BAT error box
- GRB 160709A, Swift-BAT detection and localization
- GRB 160709A: Global MASTER Net Fermi GBM Alerts observations
- GRB 160709A: Fermi GBM Observations
- GRB 160709A: Fermi-LAT detection
- SGR 1935+2154: CALET Gamma-Ray Burst Monitor detections
- GRB 160703A: Swift-XRT afterglow detection
- GRB 160705A/MAXI J0748-149: MAXI/GSC detection
- GRB 160630A: Swift detection of a burst
- GRB 160607A: Swift detection of a bright burst
- GRB 160601A: MITSuME Okayama Ks-band upper-limit
- GRB 160521B: Swift-XRT afterglow detection
- Konus-Wind observation of GRB 160521B
- GRB 160525B: Prompt enhanced Swift-XRT position
- GRB 160525B: Swift detection of a burst
- GRB 160521B: Swift-XRT observations
- GRB 160521B: Fermi-LAT detection
- GRB 160521B: Fermi GBM detection
- Konus-Wind observation of a bright burst from SGR 1935+2154
- FERMI GBM bursts from the magnetar SGR 1935+2154
- Fermi GBM triggers of SGR 1935+2154
- Trigger 686761: Swift detection of a bright burst from SGR 1935+2154
- GRB 160509A MASTER-NET observations
- Fermi GBM trigger 484574960/160510506 is not a GRB
- GRB 160509A: Fermi GBM Detection
- GRB 160509A: Fermi-LAT prompt detection of a very bright burst
- GRB 160506A: Swift detection of a burst
- ICECUBE-160427A : Pan-STARRS imaging and optical transients in the field
- VERITAS rapid follow-up observations of IceCube event 160427A
- GRB 160501A: Swift detection of a burst
- GRB 160325A: Skynet PROMPT-CTIO observations of the optical afterglow
- LIGO/Virgo G197392 / LVT151012: Identification of a GW CBC Candidate
- LIGO/Virgo G211117: EWE for NOWT of 12 days follow-up of northern sky
- GRB 160409A found in Swift BAT ground analysis
- GRB 160412A: Swift detection of a burst
- GRB 160411A: Gemini-S optical observations
- GRB 160411A: GROND Optical/NIR upper limits
- Konus-Wind observation of GRB 160410A (short/hard)
- GRB 160410A: Swift detection of a (possibly-short) burst with an optical counterpart
- LIGO/Virgo G211117: LOFAR follow-up
- GRB 160327A: Early RAPTOR Limits
- GRB 160327A: Imaging and spectroscopy from GTC
- GRB 160327A: KAIT optical afterglow confirmation
- GRB 160327A: Swift detection of a burst
- GRB 160325A: Swift detection of a burst
- LIGO/Virgo G211117: EWE for NOWT follow-up of northern sky
- LIGO/Virgo G194575: EWE for NOWT follow-up of northern sky
- GRB 160228A: GROND afterglow confirmation and X-shooter host candidate redshift
- Trigger 677981: Swift detection of IGRJ17091-3624
- GRB 160228A: RATIR Optical and NIR Observations
- GRB 160228A: Prompt enhanced Swift-XRT position
- GRB 160228A: Swift detection of a burst
- GRB 160227A: MAXI/GSC detection
- GRB 160227A: Swift detection of a burst with an optical counterpart
- GRB 160223B: CALET Gamma-Ray Burst Monitor detection
- GRB 160223A: Swift-XRT afterglow detection
- GRB 160223B: MASTER-Amur early observations
- GRB 160223B: Fermi GBM observation
- GRB 160223B: A long GRB detected by INTEGRAL
- GRB 160223A: GROND optical/NIR afterglow
- GRB 160220A: nIR observations at AAT
- LIGO/Virgo GW150914: BOOTES-3 simultaneous imaging
- LIGO/Virgo G184098: Correction for GCN Circular 18361
- LIGO/Virgo G184098: MAXI/GSC search for an X-ray counterpart of GW150914
- LIGO/Virgo G211117: LOFAR follow-up
- GRB 160203A: Skynet PROMPT-CTIO observations of the optical afterglow
- GRB 160203A: LCOGT-Cerro Tololo optical afterglow confirmation
- GRB 160131A: LCOGT-FTN optical afterglow observations
- GRB160131.35 MASTER-Net OT detection
- GRB 160121A: GROND Afterglow observations
- LIGO/Virgo G184098: MASTER final result
- Konus-Wind observation of GRB 160113A
- GRB 160117B: Swift detection of a burst with optical counterpart
- IPN Triangulation of GRB 160113A
- GRB 151225A: Correction to the trigger time of GCN 18724
- GRB 160113A: Fermi GBM detection
- GRB 160113A: iPTF P48 Observations and Optical Transient Candidates
- LIGO/Virgo G184098: Updated FAR estimate
- LIGO/Virgo G211117: Subaru Hyper Suprime-Cam follow-up observation
- GRB 160107A: MAXI/GSC detection
- Konus-Wind observation of GRB 151225A
- IPN Triangulation of GRB 151225A (short/hard)
- LIGO/Virgo G211117: Summary of Pan-STARRS transients