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"35431 results found.
- GRB 080906: Swift detection of a burst with optical afterglow
- GRB 080905A: Swift-XRT Refined Analysis
- GRB 080825C: Fermi GBM Spectral Analysis
- GRB 080905B: Swift detection of a burst with possible optical counterpart
- GRB 080905: R & I-band optical observations
- GRB 080905: Swift detection of a probably-short burst
- GRB 080903: Swift/UVOT Observations
- GRB 080903: Swift-XRT Refined Analysis
- GRB 080903: Enhanced Swift-XRT position
- GRB 080903, Swift-BAT refined analysis
- GRB 080903: optical observations
- GRB 080903: Liverpool Telescope observations
- GRB 080903: Astrotel-Caucasus optical observations
- GRB 080903: Optical afterglow candidate
- GRB 080903: TAROT Calern observatory optical observations
- GRB 080903: ROTSE-III Optical Limits
- GRB 080903: Swift detection of a burst
- GRB 080830: Fermi Gamma-ray Burst Monitor detection
- GRB080828: Swift/UVOT Upper Limits
- GRB080825B: Swift/UVOT Upper Limits
- GRB 080828: Swift-XRT detection of a possible X-ray afterglow
- Swift-BAT trigger 322590 is not a GRB
- Swift trigger 322590: BAT detection of a possible burst
- GRB 080828: SuperAGILE GRB Localization
- GRB080823: Fermi Gamma-ray Burst Monitor detection
- GRB 080824: Fermi Gamma Ray Burst Monitor detection
- GRB 080825B: pseudo-z= 0.83 from prompt emission spectrum
- 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
- GRB080825: Afterglow confirmation and redshift estimate
- GRB 080825B - optical counterpart candidate
- GRB 080825B: GRB Localization by SuperAGILE
- GRB 080822B, Swift-BAT refined analysis
- GRB 080822B: MASTER optical observation
- New Soft Gamma Repeater 0501+4516 (GRB 080822): GLAST Burst Monitor detection
- Swift Trigger 321481: A Large Flare from SGR 0501+4516
- GRB 080822B: Swift detection of a burst
- GRB080818B: GLAST Burst Monitor detection
- GRB 080822 (SGR 0501+4516): archival optical observations
- New Soft Gamma Repeater 0501+4516 was GRB 080822
- 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
- GRB080810: optical observations
- GLAST Burst Monitor detection of GRB 080812
- Radio detection of GRB 080810 with the VLA
- GRB 080810: RTT150 optical observations
- GRB 080810: Konus-Wind and Swift/BAT joint spectral analysis
- GLAST Burst Monitor detection of GRB 080810
- GRB 080810: Liverpool and Faulkes North observations
- GRB 080810: RTT150 optical observations
- GRB080810: MITSuME optical observation
- First GLAST Burst Monitor GRB Circulars
- GRB 080810: Swift/UVOT Refined Analysis
- GRB 080810: optical observations
- GRB 080810: Liverpool Telescope observations
- GRB 080810: D50 optical observation
- GRB 080810: Kanazawa optical observation
- GRB 080810: OSN follow-up
- GRB 080810: Observations from NOT
- GRB 080810: RTT150 optical observations
- GRB 080810: Swift-XRT Team refined analysis
- GRB 080810: Enhanced Swift-XRT position
- GRB 080810: KANATA optical-NIR observation, update
- GRB 080810: ROTSE-III Prompt Detection of Optical Counterpart
- GRB 080810: Keck/HIRES Spectroscopy
- GRB 080810, Swift-BAT refined analysis
- 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: VLT redshift update
- GRB 080805: Faulkes Telescope South optical observations
- GRB 080804: GROND observations
- GRB 080727B: Late VLT imaging
- GRB 080804: ATCA Radio Observations
- GRB 080805: Swift-XRT Refined Analysis
- GRB 080805: Swift/UVOT Upper Limits
- GRB 080804: Swift-XRT Refined Analysis
- GRB 080804: Swift/UVOT Refined Analysis
- GRB 080805, Swift-BAT refined analysis
- GRB 080804, Swift-BAT refined analysis
- GRB 080804: Enhanced Swift-XRT position
- GRB080804: Gemini South redshift confirmation
- GRB 080804: Faulkes Telescope South observations
- GRB080805 optical limit by "Pi of the Sky"
- GRB 080805: VLT redshift
- GRB 080805: Afterglow confirmation
- GRB 080805: GROND detection of possible afterglow
- GRB 080805: Swift detection of a burst
- GRB 080804: UVES redshift
- GRB 080804: Swift detection of a burst with optical afterglow
- GRB 080804: ROTSE-III Detection of Optical Counterpart
- GRB 080802: Swift/UVOT Upper Limits