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"26500 results found.
- SGR 0501+4516: Detection of possible optical counterpart
- GRB080825B: Swift/UVOT Upper Limits
- GRB 080828: Swift-XRT detection of a possible X-ray afterglow
- Swift trigger 322590: BAT detection of a possible burst
- GRB 080828: SuperAGILE GRB Localization
- Enhanced Swift-XRT position of SGR 0501+4516
- SGR 0501+4516: GMRT Radio Observation at 618 MHz
- SGR 0501+4516: Swift XRT measure of the spin period
- GRB080823: Fermi Gamma-ray Burst Monitor detection
- GRB 080824: Fermi Gamma Ray Burst Monitor detection
- Konus-Wind observation of GRB 080825B
- GRB080825C: GLAST Burst Monitor detection
- GRB 080825B: Swift-XRT team analysis
- Soft Gamma Repeater SGR 0501+4516: GBM Detection of multiple bursts
- Suzaku ToO Observation of SGR 0501+4516
- GRB 080825B - optical counterpart candidate
- SGR 0501+4516: radio pulsar searches with GBT and WSRT
- GRB 080825B: GRB Localization by SuperAGILE
- SGR 0501+4516: Astrotel-Caucasus optical observations
- SGR 0501+4516: UKIRT detection of possible infra-red counterpart
- SGR 0501+4516: optical observations
- SGR 0501+4516: Swift-BAT refined analysis of the 3 discovery events
- Discovery of the Spin Period of the New Soft Gamma Repeater SGR 0501+4516
- GRB080818B: GLAST Burst Monitor detection
- GRB 080822: Swift detection of a short burst
- GLAST Burst Monitor detection of a GRB: 080816B
- GLAST Burst Monitor detection of GRB 080818
- GLAST Burst Monitor detection of GRB080817B
- GLAST Burst Monitor detection of GRB 080817
- GLAST Burst Monitor detection of GRB080816
- GRB080810 - optical observations
- GLAST Burst Monitor detection of GRB 080812
- Radio detection of GRB 080810 with the VLA
- GRB 080810: Konus-Wind and Swift/BAT joint spectral analysis
- GRB 080810: Liverpool and Faulkes North observations
- First GLAST Burst Monitor GRB Circulars
- GRB 080810: Swift/UVOT Refined Analysis
- GRB 080810: Liverpool Telescope observations
- GRB 080810: Kanazawa optical observation
- GRB 080810: OSN follow-up
- GRB 080810: Swift-XRT Team refined analysis
- GRB 080810: Enhanced Swift-XRT position
- GRB 080810: KANATA optical-NIR observation, update
- GRB 080810 : optical observation with KANATA
- GRB 080810: Swift detection of a burst with a bright optical afterglow
- GRB 080723B: GROND upper limits
- GRB 080723B: XMM-Newton observation
- GRB 080805: Faulkes Telescope South optical observations
- GRB 080804: GROND observations
- GRB 080727B: Late VLT imaging
- GRB 080805: Swift-XRT Refined Analysis
- GRB 080805: Swift/UVOT Upper Limits
- GRB 080804: Swift-XRT Refined Analysis
- GRB 080804, Swift-BAT refined analysis
- GRB 080804: Enhanced Swift-XRT position
- GRB 080804: Faulkes Telescope South observations
- GRB080805 optical limit by "Pi of the Sky"
- GRB 080805: Afterglow confirmation
- GRB 080805: GROND detection of possible afterglow
- GRB 080805: Swift detection of a burst
- GRB 080804: Swift detection of a burst with optical afterglow
- GRB 080802: Swift/UVOT Upper Limits
- GRB 080802: Swift-XRT Refined Analysis
- GRB 080802: UVI Telescope Upper Limit
- GRB 080802: Swift detection of a probable burst
- GRB 080727C: Suzaku WAM observation of the prompt emission
- GRB 080727B: IR photometry
- GRB 080727C: TAROT Calern observatory optical observations
- GRB 080727B: KAIT photometry and an early lightcurve break
- GRB 080727C: Swift/UVOT Upper Limits
- Konus-Wind observation of GRB 080727B
- GRB 080727C: Swift XRT refined analysis
- GRB 080727C: Liverpool Telescope observations
- GRB 080727A: VLT upper limits
- GRB 080727C: Enhanced Swift-XRT position
- GRB080727C: RTT150 optical observations
- GRB 080727C: Swift detection of a burst
- Swift detection of XTE J1701-407
- GRB 080727B: Swift/UVOT Upper Limits
- GRB 080727B: Swift-XRT refined analysis
- GRB 080727A: Swift-XRT refined analysis
- GRB080727A: Swift/UVOT Upper Limits
- GRB 080727B: Enhanced Swift-XRT position
- GRB 080727A: Enhanced Swift-XRT position
- GRB 080727B: KAIT observations
- GRB 080727B: REM prompt observations
- GRB 080727B: Swift detection of a bright burst
- GRB 080727: Swift detection of a burst
- GRB 080726: GRB Localization by SuperAGILE
- GRB 080725, Swift-BAT refined analysis
- GRB 080723A: optical upper limit
- GRB080723B: Swift/UVOT Upper Limits
- GRB 080725: REM prompt observations
- Konus-Wind observation of GRB 080723B
- GRB 080723A: Swift/UVOT Upper Limits
- VLA radio upper limit on GRB 080721
- GRB 080723B - correction to flux conversion factor
- GRB 080723B - Swift-XRT refined analysis
- GRB 080723, Swift-BAT refined analysis
- GRB 080723B: AGILE GRID and MCAL results