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"36947 results found.
- GRB 070529: MARGE Observations
- GRB 070529: Optical aterglow from MIRO
- GRB 070529: Gemini Redshift
- GRB 070529: Swift-XRT refined analysis
- GRB 070529, Swift-BAT refined analysis
- GRB 070529: Xinglong TNT Optical Upper Limit
- GRB 070529: Swift detection of a burst with an optical aterglow
- GRB 070412: Deep Keck imaging
- Swift Triggers 280447, 280450 and 280451 are invalid
- Swift trigger 280447 is probably a Galactic transient
- GRB 070518, deep LBT photometry
- GRB 070518: MARGE Observations
- GRB 070521: pseudo-z ~ 2.28 from prompt emission spectrum
- Konus-Wind observation of GRB 070521
- GRB 070518: optical observation
- GRB070520B: NIR observations
- GRB 070521: Swift/UVOT Upper Limits
- GRB 070521, optical observation
- GRB 070521: Swift-XRT refined analysis
- GRB 070521: Keck imaging
- GROND upper limits of GRB 070521
- GRB 070521 Milagro GeV/TeV Observations
- GRB 070520B: SARA upper limit
- GRB 070520A: SARA upper limit
- GRB 070521: SARA upper limit
- GRB 070521: Subaru observations and possible host detection
- GRB 070520B: Swift/UVOT Upper Limits
- GRB 070520A: Subaru Observations
- GRB 070521, Swift-BAT refined analysis
- GRB 070520A: Swift UVOT Upper Limits
- GRB 070520B: Swift-XRT refined analysis
- GRB 070521: optical limit by Pi of the Sky
- GRB070521 : Faulkes Telescope North Observations
- GRB 070521: TAROT La Silla observatory optical observations
- GRB070521: Bright SDSS Galaxy Near XRT Error Circle
- GRB070521 - SDSS Pre-Burst Observations
- GRB 070521: Swift detection of a burst
- GRB 070520A: MITSuME Akeno optical upper limits
- GRB 070520B, Swift-BAT refined analysis
- GRB 070520A, Swift-BAT refined analysis
- GRB 070520A: Swift-XRT refined analysis
- GRB 070518: TNG observations
- GRB 070520B: Swift detection of a burst
- GRB 070520: Xinglong EST optical Upper Limit
- GRB 070520: Swift detection of a burst
- VLA observation of GRB 070518
- GRB 070518: Swift-XRT refined analysis
- GRB 070517: Gemini optical imaging
- GRB070518: UVOT refined analysis
- GRB070518: OSN observation
- GRB 070518, Swift-BAT refined analysis
- GRB 070518: OT confirmed form Xinglong TNT observation
- GRB 070518: Swift detection of a burst with optical afterglow
- GRB070517: Swift-XRT Refined Analysis
- GRB 070517, Swift-BAT refined analysis
- GRB 070517: Optical search
- GRB 070517: Swift detection of a burst
- GRB 070509: objects inside XRT error circle
- GRB 070512: pseudo-z ~ 1.39 from prompt emission spectrum
- GRB 070512: IPN localization and Konus spectrum of a bright burst
- GRB070419A: optical observations
- GRB 070419A, Deep LBT photometry
- GRB 070508: pseudo-z from 4 different spectral analyses
- GRB 070509: Swift/UVOT Upper Limits
- Konus-Wind and Konus-A observation of GRB 070508
- Swift-BAT trigger 278987 is not a GRB
- GRB 070510: Swift detection of a possible burst
- GRB070509: Swift-XRT Refined Analysis
- GRB 070508: OA fading and tentative redshift
- GRB 070509, Swift-BAT refined analysis
- GRB 070508: Suzaku/WAM observation of the prompt emission
- GRB 070509: REM observations
- GRB 070509: Swift detection of a burst
- GRB 070509: ROTSE-III Optical Limits
- GRB070508: Swift/UVOT Observations
- GRB 070508, SMARTS optical afterglow observation
- GRB 070508, Swift-BAT refined analysis
- GRB 070508: Multicolor optical observations and possible redshift limit
- GRB 070508: Swift-XRT refined analysis
- GRB 070508: Optical observation limiting magnitude
- GRB 070508: Optical afterglow detection
- GRB 070508: REM observations
- GRB 070508: TAROT La Silla observatory optical observations
- GRB 070508: Swift detection of an intense burst with an optical counterpart
- GRB070412: MAGIC telescope GeV observation
- Swift-BAT trigger 278809 is not a GRB
- GRB 070507: Swift detection of a possible cosmic ray shower event or a possible burst
- GRB 070506: VLT redshift
- GRB070506: Swift/UVOT Observations
- GRB070506: Swift XRT refined analysis
- GRB 070506, Swift-BAT Refined Analysis
- GRB 070506: Swift detection of a burst with optical afterglow
- GRB 070412, deep LBT imaging
- GRB 070429A: Swift XRT further analysis
- GRB070429B: VLT observations
- GRB 070429A: optical observations
- GRB 070309: Swift-XRT afterglow confirmation
- GRB070429B: possible host galaxy detection
- VLA observation of GRB 070429B
- Swift/UVOT observations of GRB070429B