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"20366 results found.
- GRB 091221: Enhanced Swift-XRT position
- GRB 091221: UVOT Confirmation of an Optical Afterglow
- GRB 091221: Swift detection of a burst
- Swift trigger 379449 (possible GRB) is not a burst
- GRB 091215: Faulkes Telescope North observations
- Trigger 379449: Swift detection of a possible burst
- GRB 091208A: GAO 150cm telescope Optical Observation
- GRB091208A: Swift/UVOT refined analysis
- GRB 091208B: optical observations
- GRB 091208B: GROND observations
- GRB 091208A: Swift-XRT observations
- GRB091208B: NOT optical observations
- GRB 091208A, RIMOTS optical upper limits
- GRB 091208B: MITSuME Akeno Optical Observation
- GRB 091208B: Enhanced Swift-XRT position
- GRB 091208B: MITSuME Okayama Optical Observation
- GRB 091208B, RIMOTS optical upper limits
- GRB 091208B: Swift detection of a burst with an optical afterglow
- GRB 091208B: BOOTES-3 optical afterglow
- GRB 091202: GTC & CAHA optical/nIR afterglow candidate
- GRB 091109A: GROND confirmation of redshift z = 3.5
- GRB 091127, SMARTS optical/IR afterglow observations
- GRB 091202: Swift/UVOT Upper Limits
- GRB 091202 - UVOT-enhanced XRT position
- GRB 091127: Zadko Telescope Observations
- GRB 091202: TAROT Calern observatory optical observations
- GRB 091117: Chandra Observations
- GRB 091020: MASTER-Net optical polarization observations
- GRB 091123: Fermi GBM detection of a very long burst
- GRB 091130B: Swift/UVOT Upper Limits
- GRB 091127: Skynet/PROMPT Observations of Fading
- GRB 091130B: Enhanced Swift-XRT position
- GRB 091130B: Swift detection of a burst
- GRB 091127: Radio observations
- Konus-Wind observation of GRB 091127
- GRB 091127: TAROT La Silla observatory optical observations
- GRB 091127: LABOCA/APEX submm observations
- GRB 091127: Further NOT optical observations
- GRB 091127: MASTER early optical transient polarimetry
- GRB 091127: Swift-XRT afterglow detection and analysis
- GRB 091127: TAROT La Silla observatory optical decay
- GRB 091127: Swift/UVOT observations
- GRB 091127: Swift-BAT refined analysis
- GRB 091127: NOT observations
- GRB 091127 : GROND observations
- GRB 091127: REM NIR afterglow detection
- GRB 091120: Fermi GBM observation
- GRB 091117: TNG optical observations
- GRB 091117A: Swift/UVOT followup observations
- GRB 091117: Evidence for Variability of XRT Source #1
- GRB091117: Gemini South Observations
- GRB 091117: Swift XRT refined analysis
- GRB091111: Swift XRT refined analysis
- GRB 091112: Swift-BAT refined analysis
- GRB 091031: Fermi LAT detection of a faint burst
- GRB 091111: BOOTES-3 contemporaneous imaging
- GRB 091111: BOOTES-3 observations
- GRB 091109A: GROND and VLT observations
- GRB 091109B: Swift/UVOT Upper Limits
- GRB 091109B: Enhanced Swift-XRT position
- GRB 091109B: Optical limits from Watcher
- GRB 091109B: ROTSE-III Optical Limits
- GRB 091109B: Swift detection of a short burst
- GRB 091109: BOOTES-3 observations
- GRB 091109: Swift/UVOT observations
- GRB 091109: Enhanced Swift-XRT position
- GRB091109: REM detection of the NIR afterglow
- GRB 091109: Swift detection of a burst with optical afterglow
- GRB 091029: Observations from Stardome Observatory
- GRB 091104: Swift XRT Refined Analysis
- GRB 091104: Swift/UVOT Upper Limits
- GRB 091104: Enhanced Swift-XRT position
- GRB 091104: Swift detection of a burst
- GRB 091102: LABOCA/APEX submm observations
- Fermi LAT Upper Limits on GRB 091010
- GRB 091102 : Faulkes Telescope South Upper Limits
- GRB 091102: Swift/UVOT Upper Limits
- GRB 091102: GROND Upper Limits
- GRB 091102: BOOTES-3 observations
- GRB 091102: Swift/XRT localization
- GRB 091024: optical observations
- GRB 091024: Fermi LAT upper limits
- GRB 091018, SMARTS optical/IR afterglow observations
- GRB091029: Swift/UVOT observations
- GRB 091029: Enhanced Swift-XRT position
- GRB091024 optical observations
- GRB 091029: GROND Detection of the Optical/NIR Afterglow
- GRB 091029: Swift detection of a burst with an optical counterpart
- GRB 091026: GROND Upper Limits
- Radio afterglow detection from GRB 091020
- GRB 091026: Swift/UVOT Upper Limits
- 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 091024: Super-LOTIS early observations
- GRB 091024: Fermi GBM Observations
- GRB 091024: Swift-XRT team refined analysis
- GRB 091024 : Faulkes Telescope North - Afterglow Confirmation
- GRB 091024: GRAS004 optical observations