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"19534 results found.
- 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
- GRB 080905B: Refined UVOT Analysis
- GRB 080905B: Enhanced Swift-XRT position
- GRB 080905B, Swift-BAT refined analysis
- GRB 080905A, Swift-BAT refined analysis
- GRB 080906: Swift detection of a burst with optical afterglow
- GRB 080905A: Swift-XRT Refined 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: Astrotel-Caucasus optical observations
- GRB 080903: TAROT Calern observatory optical observations
- GRB 080903: ROTSE-III Optical Limits
- GRB 080903: Swift detection of a burst
- SGR 0501+4516: preliminary results of the first XMM-Newton observation
- 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
- SGR 0501+4516: Decline in Activity
- SGR 0501+4516: Proximity to supernova remnant HB9
- Enhanced Swift-XRT position of SGR 0501+4516
- SGR 0501+4516: Swift XRT measure of the spin period
- GRB 080825B: Swift-XRT team analysis
- Soft Gamma Repeater SGR 0501+4516: GBM Detection of multiple bursts
- SGR 0501+4516: radio pulsar searches with GBT and WSRT
- Konus-Wind observations of new SGR 0501+4516
- SGR 0501+4516: MDM Optical Observations
- GRB 080822B, Swift-BAT refined analysis
- SGR 0501+4516: WSRT Radio Observations
- Trigger 321551: Continued Large Flaring of SGR 0501+4516
- New Soft Gamma Repeater 0501+4516 (GRB 080822): GLAST Burst Monitor detection
- SGR 0501+4516: optical observations
- Swift Trigger 321481: A Large Flare from SGR 0501+4516
- 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
- GRB 080822B: Swift detection of a burst
- Third event from SGR 0501+4516
- New Soft Gamma Repeater 0501+4516 was GRB 080822
- GRB 080822: Swift detection of a short burst
- Radio detection of GRB 080810 with the VLA
- GRB 080810: Konus-Wind and Swift/BAT joint spectral analysis
- GLAST Burst Monitor detection of GRB 080810
- GRB 080810: Swift/UVOT Refined Analysis
- GRB 080810: D50 optical observation
- GRB 080810: Kanazawa optical observation
- GRB 080810: Swift-XRT Team refined analysis
- GRB 080810: Enhanced Swift-XRT position
- GRB 080810: ROTSE-III Prompt Detection of Optical Counterpart
- GRB 080810, Swift-BAT refined analysis
- GRB 080810: Swift detection of a burst with a bright optical afterglow
- GRB 080723B: XMM-Newton observation
- GRB 080727B: Late VLT imaging
- GRB 080805: Swift-XRT Refined Analysis