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"26499 results found.
- Konus-Wind observation of GRB 080507
- GRB 080319B: Further HST observations and underlying host
- GRB 080506: NAYUTA Optical Observation
- GRB 080507: Suzaku WAM observation of the prompt emission
- GRB 080507: Swift XRT analysis confirms the X-ray afterglow
- GRB 080507: Keck photometry
- GRB 080503: Chandra Observation of X-ray Rebrightening or Flattening
- GRB 080503: Hubble Space Telescope Imaging
- GRB 080507: Optical Afterglow
- GRB 080506:Optical observations from HCT
- GRB 080506: VLA radio upper limit
- GRB 080507: GRB localization by SuperAGILE
- GRB 080506: Swift XRT refined analysis
- GRB080506: Swift/UVOT observations
- GRB 080506, Swift-BAT refined analysis
- GRB080503, RIMOTS optical upper limit
- GRB 080506: Observations from NOT
- GRB 080506: Enhanced Swift-XRT position
- GRB 080506: Swift detection of a burst with optical afterglow
- GRB 080503: VLA radio upper limit
- GRB 080503: Observations from NOT
- GRB 080503: Slow-rise optical AG ?
- GRB 080430: TLS imaging one day after the GRB
- GRB 080503: No further optical rebrightening
- GRB 080503: Late-time Optical rebrightening (possible mini-SN)
- GRB080503 XRT refined analysis
- GRB 080430
- GRB 080503: Enhanced Swift-XRT position
- GRB 080503: New candidate afterglow/host in Gemini imaging
- GRB 080503: Swift detection of a short burst
- GRB 080411: Continued Swift Monitoring
- GRB080430: Swift/UVOT observations
- VLA radio upper limit on GRB 080430
- GRB 080430: Swift-XRT refined analysis
- GRB 080430: Enhanced Swift-XRT position
- GRB 080430: Spectroscopy from CAHA
- GRB 080430 - SDSS Pre-Burst Observations
- GRB 080430: Swift detection of a burst with optical afterglow
- GRB 080430: TAROT Calern observatory optical observations
- GRB 080426: Swift-XRT refined analysis
- GRB080426: Swift/UVOT upper limits
- GRB 080426: Enhanced Swift-XRT position
- GRB 080426: Swift detection of a possibly short burst
- GRB 080320 : Faulkes Telescope North Observations
- GRB 080319A : Liverpool and Faulkes Telescopes Observations
- GRB080319A: MAGIC telescope GeV observation
- GRB 080420A: ROTSE-III Optical Limits on a possible short burst
- GRB080310, BVRcIc field calibration
- GRB 080413A: Suzaku/WAM and Swift/BAT joint spectral analysis
- GRB 080413B: Rapid PROMPT Observations
- Swift XRT and UVOT observations of GRB080414
- GRB 080319B: Jet Break, Energetics, Supernova
- GRB 080413B: Faulkes Telescope South optical afterglow observations
- GRB 080413A: Liverpool Telescope and Faulkes Telescope South optical observations
- GRB 080413A: Suzaku WAM observation of the prompt emission
- GRB 080413B: Suzaku WAM observation of the prompt emission
- GRB 080414: RTT150 optical observations
- GRB 080414 Watcher observations
- GRB 080414: A long GRB detected by INTEGRAL
- VLA radio observations of GRB 080413B
- VLA radio observations of GRB 080413A
- GRB080413B
- Swift-BAT spectral lag analysis of GRB 080413B
- GRB 080413a, SMARTS optical/IR afterglow observations
- GRB 080413B: Swift XRT refined analysis
- GRB080413A: Swift/UVOT observations
- GRB 080413A: Swift-XRT refined analysis
- GRB080413B: REM NIR & Optical Observation
- GRB 080413B: GROND detection of afterglow in all bands
- GRB 080413B: Swift detection of a possibly short burst with optical counterpart
- GRB 080413A: REM detection of the NIR Afterglow
- GRB 080413: Enhanced Swift-XRT position
- GRB 080413: TAROT Calern observatory optical observations
- GRB 080413: Swift detection of a burst with an optical afterglow
- GRB 080411: Swift/UVOT refined analysis
- GRB 080411: Swift-XRT Refined Analysis
- Konus-Wind observation of GRB 080411
- GRB 080411: Enhanced Swift-XRT position
- GRB 080411: GROND detection of optical afterglow candidate
- GRB080330: MAGIC telescope GeV observation
- GRB 080411: Swift detection of a bright burst
- GRB 080409: Swift-BAT refined analysis
- GRB 080408: GROND detection of optical/NIR afterglow candidate
- GRB 080330 optical observations
- Swift/UVOT observations of GRB080409
- GRB 080409: Swift XRT refined analysis
- GRB 080409: Enhanced Swift-XRT position
- GRB 080409: REM optical/NIR observations
- GRB 080409: Swift detection of a burst
- GRB 080408: Analysis of AGILE Gamma-ray data
- GRB 080408: GRB Localization by SuperAGILE
- GRB 080319A: Early RAPTOR optical limits
- GRB 080319B: HST observations
- GRB 080405: Swift-BAT refined analysis
- GRB 080405: Swift-XRT position
- GRB 080405: Mars Oddysey and Swift-BAT detection, possible host galaxy
- GRB 080325: optical upper limit
- GRB 080328: GAO 150cm telescope Optical Observation
- GRB080330: Improved Swift XRT Position
- GRB080328, RIMOTS optical upper limit