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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').
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"

55 results found.

  1. Fermi GRB 251006B: Global MASTER-Net observations report
  2. Swift detection of the Soft Gamma Repeater PSR J1647-4552
  3. GRB 241113A: KAIT optical observations
  4. Fermi-LAT gamma-ray observations of IceCube-240808A
  5. LIGO/Virgo/KAGRA S240527fv: Updated Sky localization
  6. Fermi trigger No 732299243: Global MASTER-Net observations report
  7. LIGO/Virgo/KAGRA S231008ap: Identification of a GW compact binary merger candidate
  8. IceCube-230708A - IceCube observation of a high-energy neutrino candidate track-like event
  9. Fermi trigger No 675411172: Global MASTER-Net observations report
  10. IceCube-220221A - IceCube observation of a high-energy neutrino candidate track-like event
  11. Fermi-LAT Gamma-ray Observations of IceCube-211023A
  12. IceCube-211023A - IceCube observation of a high-energy neutrino candidate track-like event
  13. Fermi-LAT Gamma-ray Observations of IceCube-210730A
  14. Fermi GRB 210615A: Global MASTER-Net observations report
  15. Fermi-LAT Gamma-ray Observations of IceCube-201120A
  16. AX J1846.4-0258: Swift-BAT refined analysis
  17. Swift Detection of an SGR-like flare from AX J1846.4-0258
  18. Swift-XRT observations of IceCube 200615A
  19. Fermi-LAT ANTARES 200127.79 coincidence: MASTER alert observation and presence of young pulsar close to error-box
  20. LIGO/Virgo S191110af: Potential pulsar counterparts
  21. Fermi-LAT Gamma-ray Observations of IceCube-191001A
  22. Trigger 896552: Swift detection of PSR B1055-52
  23. Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
  24. Swift Trigger on AXP CXOU J164710.2-455216/PSR J1647-4552
  25. Fermi-LAT Gamma-ray Observations of IceCube-171106A
  26. Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
  27. Trigger 780207: Swift triggers again on AXP CXOU J164710.2-455216/PSR J1647-4552
  28. Swift Trigger on AXP CXOU J164710.2-455216/PSR J1647-4552
  29. GRB 170519A: iTelescope T11 optical observations
  30. Swift Trigger on AXP CXOU J164710.2-455216
  31. GBM observation of SGR-like burst from the direction of PSR 1119-6127
  32. Trigger 706396: Swift detection of a short burst from PSR 1119-6127
  33. SGR 1935+2154: AbAO optical upper limit
  34. IPN Triangulation of SGR-like burst 130913 - probable association with SGR/AXP 1E1841-045
  35. GRB 120927A: Swift/UVOT Upper Limits
  36. GRB 120226A: Fermi-GBM and Fermi-LAT detections; LAT position retraction
  37. Swift detection of short bursts from PSR J1647-4552
  38. SGR J1834.9-0846: A Neutron Star in W41?
  39. Swift J1822.3-1606
  40. SGR 1E 1841-045: Swift detection of a soft gamma repeater burst
  41. An SGR-like burst from the magnetar 1E 1841-04.5 in Kes 73
  42. GRB 100116A: Suzaku WAM observation of the prompt emission
  43. GRB 070223: Optical Observations
  44. VLA observation of GRB 070223
  45. GRB 070223: Swift-XRT Refined Analysis
  46. GRB 051221: Swift/UVOT upper limits
  47. GRB050701: Swift-BAT Refined analysis
  48. Swift trigger 143708 is really GRB 050701
  49. The Radio Afterglow from the X-ray Rich GRB 011030
  50. GRB 011030, WSRT radio observations
  51. GRB011030 - further refinement WFC position
  52. GRB011030: radio search
  53. GRB 011030, R-band observations
  54. BeppoSAX ALERT: Possible X-ray rich GRB011030
  55. GRB990123, 15-GHz limits

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