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"26349 results found.
- GRB 091024: Burst was outside the Swift-BAT FOV after T0(BAT)+460sec
- GRB 091026: Swift-XRT refined analysis
- GRB 091026: Enhanced Swift-XRT position
- Konus-Wind and Konus-RF observations of GRB 091024
- GRB 091026: Swift detection of a Gamma Ray Burst
- GRB091024 Swift/UVOT Upper Limits
- GRB 091020: Early TLS Multicolor detections, red afterglow
- GRB 091024: KAIT optical afterglow observations
- GRB091024: VRcIc Afterglow Observations
- GRB 091024: Swift-BAT refined analysis
- GRB 091024: Fermi GBM Observations
- GRB 091024: Swift-XRT team refined analysis
- Swift-BAT trigger 373691 is a galactic bulge transient
- GRB 091024 : Faulkes Telescope North - Afterglow Confirmation
- GRB 091024: Swift detection of a burst
- GRB 091018: Skynet/PROMPT Continued Observations of Fading
- GRB 091020: Lick observations
- Konus-Wind observations of GRB 091010
- GRB 091020: Swift-XRT refined analysis
- GRB 091018: Swift XRT refined analysis
- GRB091020 Swift/UVOT observations
- GRB 091020: MASTER optical transient polarimetry
- GRB 091020, Swift-BAT refined analysis
- GRB 091020: Enhanced Swift-XRT position
- GRB 090926A: Late-time Gemini South Observations and Possible Jet Break
- GRB 091020: Swift detection of a burst with an optical afterglow
- GRB 091018: miniTAO/ANIR Observations
- GRB 091018: Skynet/PROMPT Observations of Fading
- Konus-RF observation of GRB 091018
- GRB 091018: VLT/X-shooter spectra
- GRB091018: Swift/UVOT observations
- GRB 091018: Swift-BAT refined analysis
- GRB 091018: GROND observations
- GRB091018: Magellan Echellette Observations
- GRB 091018: Enhanced Swift-XRT position
- GRB 091018: Swift detection of a burst with optical afterglow
- GRB 091010: optical obsevation
- GRB 090726 R band observations
- GRB 090815: a faint long GRB localized by INTEGRAL
- GRB 091010: Swift-XRT refined analysis
- GRB 091010: Suzaku WAM observation of the prompt emission
- GRB 091010: AGILE-MCAL measurement and GRID upper limit
- Radio observation of GRB090927 with ATCA
- Radio observation of GRB090926a with ATCA
- Radio observation of GRB080916c with ATCA
- GRB 091010: Fermi GBM observation
- Konus-Wind observations of GRB 091010
- GRB 091010: Enhanced XRT position
- Detection of a short GRB 090929A by RT-2 Experiment
- RT-2 observation of the bright GRB 090926A
- GRB 091010: Swift-XRT position
- GRB 091003A: Suzaku WAM observation of the prompt emission
- Konus-Wind observation of GRB 091003A
- GRB 090929B: Suzaku WAM observation of the prompt emission
- GRB 090929A: Suzaku WAM observation of the prompt emission
- GRB 091003: Swift-XRT confirmation of fading afterglow
- GRB 091003: UVOT-enhanced XRT position
- GRB 091003A: Fermi LAT detection
- GRB 091003A: Fermi GBM detection
- GRB 090929A, Swift-BAT refined analysis
- GRB 090929B, Swift-BAT refined analysis
- GRB 090929A: Swift-XRT non-detection
- Konus-Wind observation of GRB 090929A
- Konus-Wind observation of GRB 090929B
- GRB 090927: Fermi GBM observation
- GRB 090929B: Swift-XRT refined analysis
- GRB 090926A: Fermi LAT and GBM refined analysis
- GRB 090929B: Swift/UVOT Observations
- Konus-RF observation of GRB 090929A
- Correction: GRB 090929B: Enhanced Swift-XRT position
- GRB 090929: Enhanced Swift-XRT position
- GRB 090929B: Swift detection of a burst
- GRB 090929A: Fermi GBM detection
- GRB090926A: Swift-XRT refined analysis
- GRB 090927: Faulkes Telescope South Detection of the Optical Afterglow
- Konus-Wind and Konus-RF observations of GRB 090926A
- GRB 090926B: Fermi GBM detection
- GRB 090927, Swift-BAT refined analysis of the possibly short burst
- Swift/UVOT observations of GRB 090927
- GRB 090926A: Suzaku WAM observation of the prompt emission
- GRB 090927: Enhanced Swift-XRT position
- GRB090926B: Swift/UVOT Upper Limits
- GRB090926A: Swift/UVOT observations
- GRB 090927: Swift detection of a short burst
- GRB 090926B: MAXI GSC detection
- GRB 090926B: Swift XRT refined analysis
- GRB 090926B: Swift-BAT refined analysis
- GRB 090926A: Swift/UVOT detection of an optical afterglow
- GRB090926A: UVOT-enhanced XRT position
- GRB 090926B: Swift detection of a burst
- GRB 090926: Fermi LAT detection
- GRB 090926: Fermi GBM detection
- GRB 090925: Fermi GBM detection
- GRB090904B : IRSF NIR upper limit
- GRB 090922A: Fermi GBM detection
- GRB 090915: GROND upper limits
- GRB 090915: SARA detection of afterglow candidate
- GRB 090916, Swift-BAT refined analysis
- GRB 090915: Swift-XRT detection of a fading X-ray counterpart
- GRB 090916: Swift detection of a short burst