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"19592 results found.
- GRB081008: Swift/UVOT observations
- GRB 081008: Enhanced Swift-XRT position
- GRB 081008: Swift detection of a burst with optical afterglow
- GRB 081008: ROTSE-III Detection of Optical Counterpart
- GRB081007: Swift/UVOT Observations
- GRB 081007, Swift-BAT refined analysis
- GRB 081007: Early RAPTOR measurements of optical counterpart
- GRB 081007: Swift-XRT Team refined analysis
- GRB 081007: Enhanced Swift-XRT position
- GRB 081007: Swift detection of a burst with optical afterglow
- AXP 1E 1547.0-5408: Swift/UVOT Upper Limits
- GRB 081003B: Swift-XRT upper limit
- GRB 081003A: OSN optical observations
- AXP 1E1547.0-5408: Swift-XRT Team refined analysis
- GRB 081003A: Swift-XRT Team position and analysis
- Swift-BAT refined analysis of AXP 1E1547.0-5408 (Trigger 330353)
- GRB 080928: Fermi GBM detection
- AXP 1E1547.0-5408 (SGR 1550-5418): Fermi GBM detection
- SGR 1550-5418 = AXP 1E1547.0-5408 (Trigger 330353)
- Swift discovery of a new Soft Gamma Repeater SGR 1550-5418
- Trigger 330353: Swift detection of a Galactic short soft burst
- GRB 081001: Observations from OSN
- GRB 081001: Swift UVOT Observations
- GRB 081001: Swift-XRT position
- GRB 080928: Watcher observations
- GRB 080928: VLT redshift
- GRB 080928: Swift-XRT refined analysis
- GRB 080928: Swift/UVOT observations
- GRB 080928, Swift-BAT final refined analysis
- GRB 080928: Enhanced Swift-XRT position
- GRB 080928, Swift-BAT initial refined analysis
- GRB 080928A: ROTSE-III Confirmation of Optical Counterpart
- GRB 080928: Swift detection of a burst with an optical counterpart
- Swift-BAT trigger 325707 is not a GRB
- Swift trigger 325707: Swift/UVOT Upper Limits
- Swift trigger 325707: Swift-XRT upper limit
- Swift detection of a possible GRB (trigger 325707)
- GRB080916A: Suzaku WAM observation of the prompt emission
- GRB 080922: Swift/UVOT Upper Limits
- GRB080922: Swift-XRT upper limit
- Trigger 324561: IGR J08408-4503 detected by Swift
- GRB 080919: Swift/UVOT Refined Analysis
- GRB 080919: Swift-XRT refined analysis
- GRB 080919, Swift-BAT refined analysis
- GRB 080919: Swift detection of a short burst
- GRB080913: Swift-BAT spectral lag
- SGR 0501+4516: preliminary results of the Suzaku ToO observation
- GRB 080916A: Fermi GBM detection
- GRB 080916C: Swift UVOT Refined Analysis
- GRB 080916C: Swift XRT refined analysis
- GRB 080916B: Swift-XRT refined analysis
- Konus-Wind observation of GRB 080916A
- GRB 080916C: GROND Detection of the Optical Afterglow Candidate
- GRB 080913: Konus-Wind and Swift/BAT joint spectral analysis
- GRB 080916C: Enhanced XRT position
- GRB 080916C: Swift/XRT detection of possible afterglow
- GRB 080916B: Swift UVOT Refined Analysis
- GRB 080916B, Swift-BAT refined analysis
- GRB080916A: Refined Swift/UVOT Observations
- GRB 080916B: Enhanced Swift-XRT position
- GRB 080916A: Swift XRT refined analysis
- GRB 080916A, Swift-BAT refined analysis
- GRB 080916B: Swift-XRT afterglow detection
- GRB 080916A: Enhanced Swift-XRT position
- GRB 080916B: Swift detection of a burst
- GRB 080916: Swift detection of a burst with optical afterglow
- GRB 080915B, Swift-BAT refined analysis
- GRB 080915B: Swift detection of a burst
- GRB 080915: Swift/UVOT Upper Limits
- GRB 080915: Swift-XRT afterglow detection and analysis
- GRB 080915, Swift-BAT refined analysis
- GRB 080915: ROTSE-III Optical Limits
- GRB 080915: Swift detection of a burst
- GRB 080913: Swift-XRT refined analysis
- GRB080913: Swift/UVOT Upper Limits
- GRB 080913: GROND photo-z
- GRB 080913, Swift-BAT refined analysis
- GRB 080913: VLT/FORS2 observations
- GRB 080913: Enhanced Swift-XRT position
- GRB 080913: GROND observation of a high-z optical/NIR afterglow candidate
- GRB 080913: Swift detection of a burst
- GRB 080906: Watcher observations
- Swift-BAT/-XRT refined analysis on trigger 324362 (LS I +61 303)
- SGR J0501+4516: radio pulsar searches with GBT and WSRT
- Swift trigger 324362 (LS I +61 303 ?): XRT
- GRB 080905B: Photometric Redshift for the 2MASS Galaxy
- Swift trigger 324362 (LS I +61 303 ?)
- GRB080905A: Swift/UVOT Upper Limits
- GRB 080905B: Watcher optical detection
- GRB 080905B: Fermi Gamma-ray Burst Monitor detection
- GRB 080905A: Fermi Gamma-ray Burst Monitor detection
- GRB 080905A: Enhanced Swift-XRT position
- Swift Trigger 324122 is again known source Swift J1842.5-1124
- Swift Trigger 324116 is known source again
- Swift Trigger 324112 is known source Swift J1842.5-1124
- GRB 080906: Refined Swift/UVOT Observations
- GRB 080906: Swift-XRT Refined Analysis
- GRB 080906, Swift-BAT refined analysis
- GRB 080906: GROND observations of the optical/NIR afterglow
- GRB 080905B: Swift-XRT Refined Analysis