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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"

19861 results found.

  1. GRB 080905B: Enhanced Swift-XRT position
  2. GRB 080906: Swift detection of a burst with optical afterglow
  3. GRB080825C: Fermi-LAT observations
  4. GRB 080905B: Swift detection of a burst with possible optical counterpart
  5. GRB 080905: Swift detection of a probably-short burst
  6. GRB 080903: Swift/UVOT Observations
  7. GRB 080903: Swift-XRT Refined Analysis
  8. GRB 080903: Enhanced Swift-XRT position
  9. GRB 080903: optical observations
  10. GRB 080903: Liverpool Telescope observations
  11. GRB 080903: Optical afterglow candidate
  12. GRB 080903: TAROT Calern observatory optical observations
  13. GRB 080903: Swift detection of a burst
  14. SGR 0501+4516: Spin Down Rate and Inferred Dipole Magnetic Field
  15. SGR 0501+4516: Confirmation of the NIR counterpart
  16. GRB080828: Swift/UVOT Upper Limits
  17. SGR 0501+4516: Detection of possible optical counterpart
  18. GRB080825B: Swift/UVOT Upper Limits
  19. GRB 080828: Swift-XRT detection of a possible X-ray afterglow
  20. Swift-BAT trigger 322590 is not a GRB
  21. Swift trigger 322590: BAT detection of a possible burst
  22. Enhanced Swift-XRT position of SGR 0501+4516
  23. SGR 0501+4516: GMRT Radio Observation at 618 MHz
  24. GRB 080825B: Swift-XRT team analysis
  25. SGR 0501+4516: Fermi GBM (formerly GLAST Burst Monitor) observations of three exceptionally intense outbursts
  26. Suzaku ToO Observation of SGR 0501+4516
  27. Konus-Wind observations of new SGR 0501+4516
  28. SGR 0501+4516: Astrotel-Caucasus optical observations
  29. SGR 0501+4516: UKIRT detection of possible infra-red counterpart
  30. Trigger 321551: Continued Large Flaring of SGR 0501+4516
  31. SGR 0501+4516: optical observations
  32. Discovery of the Spin Period of the New Soft Gamma Repeater SGR 0501+4516
  33. GRB 080822: Swift detection of a short burst
  34. GLAST Burst Monitor detection of GRB080816
  35. GRB080810 - optical observations
  36. Radio detection of GRB 080810 with the VLA
  37. First GLAST Burst Monitor GRB Circulars
  38. GRB 080810: Swift/UVOT Refined Analysis
  39. GRB 080810: Liverpool Telescope observations
  40. GRB 080810: Kanazawa optical observation
  41. GRB 080810: OSN follow-up
  42. GRB 080810: Enhanced Swift-XRT position
  43. GRB 080810: KANATA optical-NIR observation, update
  44. GRB 080810 : optical observation with KANATA
  45. GRB 080810: Swift detection of a burst with a bright optical afterglow
  46. GRB 080723B: GROND upper limits
  47. GRB 080805: Faulkes Telescope South optical observations
  48. GRB 080804: GROND observations
  49. GRB 080727B: Late VLT imaging
  50. GRB 080805: Swift-XRT Refined Analysis
  51. GRB 080805: Swift/UVOT Upper Limits
  52. GRB 080804: Swift/UVOT Refined Analysis
  53. GRB 080804: Enhanced Swift-XRT position
  54. GRB 080804: Faulkes Telescope South observations
  55. GRB080805 optical limit by "Pi of the Sky"
  56. GRB 080805: Afterglow confirmation
  57. GRB 080805: GROND detection of possible afterglow
  58. GRB 080805: Swift detection of a burst
  59. GRB 080804: Swift detection of a burst with optical afterglow
  60. GRB 080802: Swift/UVOT Upper Limits
  61. GRB 080802: UVI Telescope Upper Limit
  62. GRB 080802: Swift detection of a probable burst
  63. GRB 080727B: IR photometry
  64. GRB 080727C: TAROT Calern observatory optical observations
  65. GRB 080727B: KAIT photometry and an early lightcurve break
  66. GRB 080727C: Swift/UVOT Upper Limits
  67. GRB 080727C: Liverpool Telescope observations
  68. GRB 080727A: VLT upper limits
  69. GRB 080727C: Enhanced Swift-XRT position
  70. GRB080727C: RTT150 optical observations
  71. GRB 080727C: Swift detection of a burst
  72. Swift detection of XTE J1701-407
  73. GRB 080727B: Swift/UVOT Upper Limits
  74. GRB080727A: Swift/UVOT Upper Limits
  75. GRB 080727B: Enhanced Swift-XRT position
  76. GRB 080727A: Enhanced Swift-XRT position
  77. GRB 080727B: REM prompt observations
  78. GRB 080727B: Swift detection of a bright burst
  79. GRB 080727: Swift detection of a burst
  80. GRB 080726: GRB Localization by SuperAGILE
  81. GRB 080723A: optical upper limit
  82. GRB080723B: Swift/UVOT Upper Limits
  83. GRB 080725: REM prompt observations
  84. GRB 080723A: Swift/UVOT Upper Limits
  85. VLA radio upper limit on GRB 080721
  86. GRB 080723, Swift-BAT refined analysis
  87. GRB 080723: Enhanced Swift-XRT position
  88. GRB 080723: Swift detection of a burst
  89. GRB 080721: Enhanced Swift-XRT position
  90. GRB 080721, Swift-BAT refined analysis
  91. GRB 080721: Swift detection of a burst with a bright optical counterpart.
  92. Trigger 317393: Swift detection of a possible GRB
  93. Trigger 317205: Swift detection of an outburst from XTE J1701-407
  94. GRB 080714: GROND confirmation of the optical/NIR afterglow
  95. GRB 080714: Swift/UVOT Detection of an Optical Afterglow
  96. GRB 080714: Enhanced Swift-XRT position
  97. GRB 080714: Swift-BAT refined analysis
  98. GRB 080714: Swift detection of a burst
  99. GRB 080702A: optical upper limit
  100. GRB 080603A: CrAO optical observations

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