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 131118A: Fermi GBM detection
- GRB 131117A: Swift-XRT refined Analysis
- GRB 131108A: Swift-XRT observations
- IPN triangulation of GRB 131108A
- GRB 131105A: Swift-XRT refined Analysis
- GRB 131105A: VLT/X-shooter optical afterglow candidate
- GRB 131103A: Swift-XRT refined Analysis
- GRB 131031A: 1.23m CAHA I-band and 1.5m OSN R-band observations of Swift/BAT error circle
- GRB 131030A: Swift-XRT refined Analysis
- GRB 131024B: Mondy optical upper limits
- GRB 131024B: Fermi GBM observation
- GRB 131024B: Swift-XRT refined Analysis
- Fermi GBM trigger 13121024.436 is not a GRB
- GRB 131024B: Nanshan optical upper limit
- GRB 131024A: Swift-XRT refined Analysis
- GRB 131024A: Skynet R-COP optical observations
- IPN triangulation of GRB 131011B (Swift Trigger 574266)
- GRB 131018A: Swift-XRT refined Analysis
- GRB131018A, optical observations
- Fermi 403206457 / GRB 131011A: AAO optical observations
- GRB 131014A: Swift detection of a possible X-ray afterglow
- Swift-XRT detection of iPTF 13dsw/Fermi403206457
- Fermi403206457: NOT optical observations
- Fermi403206457: iPTF detection of a possible optical afterglow
- Trigger 574266 is not a Swift detection of a known source
- GRB 131004A: Swift-XRT refined Analysis
- GRB 131002B: Swift-XRT Refined Analysis
- GRB 131002A: Swift-XRT refined Analysis
- GRB 131001A detected in ground analysis of Swift-BAT data
- IPN Observations of GRB 130925A
- GRB 130929A: Swift-XRT refined Analysis
- Observation of possible GRB/TDE 130925A by INTEGRAL/SPI-ACS: three activity episodes
- GRB 130925A: Historical non-detection from Rosat-HRI
- GRB 130925A: Initial Similarities to Swift J1644+57
- GRB 130925A: Swift detection of a burst
- GRB 130919A: Swift detection of a burst
- GRB 130912A: WHT confirmation of optical counterpart
- GRB 130912A: Swift-XRT refined Analysis
- GRB 130831A: ISON-Kislovodsk optical observations
- Swift Trigger 569022: a possible GRB
- GRB 130831B: Swift-XRT refined Analysis
- GRB 130831A: Swift-XRT refined Analysis
- IPN triangulation of GRB130821A
- GRB 130821A: Weihai optical upper limit
- GRB 130822A: Swift-XRT refined Analysis
- GRB 130816A: Swift-XRT refined Analysis
- GRB 130816B: Swift-XRT refined Analysis
- IPN Triangulation of GRB 130812B (long/soft)
- GRB 130812A: Swift-XRT refined Analysis
- GRB 130812A: Swift detection of a burst
- GRB 130806A: Swift-XRT refined Analysis
- GRB 130803A: Swift-XRT refined Analysis
- GRB 130727A: Swift-XRT refined Analysis
- GRB 130725A: Swift-XRT refined Analysis
- GRB 130725B: Swift-XRT refined Analysis
- GRB 130725B: Swift detection of a burst
- Fermi Gamma-ray Burst Monitor trigger 396447899 / 130725517 is not a GRB
- GRB 130722A: Swift-XRT refined Analysis
- GRB 130702A: Continued P60 observations
- Fermi394416326: iPTF detection of a possible optical afterglow
- GRB 130701A: MITSuME Akeno Optical observation
- GRB 130701A: Swift-XRT refined Analysis
- GRB 130627A: Swift-XRT refined Analysis
- GRB 130625A: Swift-XRT refined Analysis
- GRB 130603B: First epoch of XMM-Newton observations
- Swift Trigger 558828 is not an interesting event
- GRB 130609B: Suzaku WAM observation of the prompt emission
- GRB 130615A: Swift-XRT refined Analysis
- GRB 130612A: Swift-XRT refined Analysis
- IPN Triangulation of GRB 130610B (long/multipeaked)
- GRB 130610A: Swift-XRT refined Analysis
- GRB 130609B: Swift-XRT refined Analysis
- GRB 130606A - Liverpool Telescope and Faulkes Telescope North optical observations
- GRB 130608A: Swift-XRT refined Analysis
- GRB 130609A: Swift-XRT refined Analysis
- Swift Trigger 557674 was due to an onboard position error
- Swift Trigger 557674 is a probable new Galactic transient
- GRB 130606A: Swift-XRT refined Analysis
- GRB 130606A: AAO optical observations
- GRB 130605A: Swift-XRT refined Analysis
- GRB 130604A: Swift-XRT refined Analysis
- GRB 130603B: Swift-XRT refined Analysis
- GRB 130603A: Swift-XRT refined Analysis
- GRB 130518A: Suzaku WAM observation of the prompt emission
- GRB 130529A: Swift-XRT refined Analysis
- GRB 130528A: Swift-XRT refined Analysis
- GRB 130527A: Swift-XRT refined Analysis
- GRB 130527A: Prompt enhanced Swift-XRT position
- GRB 130521B: Suzaku WAM observation of the prompt emission
- Konus-Wind observation of GRB 130521B
- IPN Triangulation of GRB 130521B
- GRB 130518A: P60 Afterglow Observations
- GRB 130515A: Swift-XRT refined Analysis
- GRB 130514A: Swift-XRT refined Analysis
- GRB 130514A: Skynet/PROMPT/DSO Detections
- GRB 130427A: optical observations
- GRB 130513A: Swift-XRT detection of the afterglow.
- GRB 130511A: Swift-XRT refined Analysis
- GRB 130508A: Refined Swift-XRT analysis: Correction to GCN 14612
- GRB 130504B: Suzaku WAM observation of the prompt emission