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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"

19090 results found.

  1. SGR 0501+4516: Astrotel-Caucasus optical observations
  2. SGR 0501+4516: UKIRT detection of possible infra-red counterpart
  3. SGR 0501+4516: optical observations
  4. SGR 0501+4516: Swift-BAT refined analysis of the 3 discovery events
  5. Discovery of the Spin Period of the New Soft Gamma Repeater SGR 0501+4516
  6. GRB080818B: GLAST Burst Monitor detection
  7. GRB 080822: Swift detection of a short burst
  8. GRB080810 - optical observations
  9. GRB080810: optical observations
  10. Radio detection of GRB 080810 with the VLA
  11. GRB 080810: Swift/UVOT Refined Analysis
  12. GRB 080810: Liverpool Telescope observations
  13. GRB 080810: Kanazawa optical observation
  14. GRB 080810: OSN follow-up
  15. GRB 080810: Enhanced Swift-XRT position
  16. GRB 080810: KANATA optical-NIR observation, update
  17. GRB 080810 : optical observation with KANATA
  18. GRB 080810: Swift detection of a burst with a bright optical afterglow
  19. GRB 080723B: GROND upper limits
  20. GRB 080805: Faulkes Telescope South optical observations
  21. GRB 080804: GROND observations
  22. GRB 080727B: Late VLT imaging
  23. GRB 080805: Swift-XRT Refined Analysis
  24. GRB 080805: Swift/UVOT Upper Limits
  25. GRB 080804: Enhanced Swift-XRT position
  26. GRB 080804: Faulkes Telescope South observations
  27. GRB080805 optical limit by "Pi of the Sky"
  28. GRB 080805: Afterglow confirmation
  29. GRB 080805: GROND detection of possible afterglow
  30. GRB 080805: Swift detection of a burst
  31. GRB 080804: Swift detection of a burst with optical afterglow
  32. GRB 080802: Swift/UVOT Upper Limits
  33. GRB 080802: UVI Telescope Upper Limit
  34. GRB 080802: Swift detection of a probable burst
  35. GRB 080727B: IR photometry
  36. GRB 080727C: TAROT Calern observatory optical observations
  37. GRB 080727B: KAIT photometry and an early lightcurve break
  38. GRB 080727C: Swift/UVOT Upper Limits
  39. GRB 080727C: Liverpool Telescope observations
  40. GRB 080727A: VLT upper limits
  41. GRB 080727C: Enhanced Swift-XRT position
  42. GRB080727C: RTT150 optical observations
  43. GRB 080727C: Swift detection of a burst
  44. Swift detection of XTE J1701-407
  45. GRB 080727B: Swift/UVOT Upper Limits
  46. GRB080727A: Swift/UVOT Upper Limits
  47. GRB 080727B: Enhanced Swift-XRT position
  48. GRB 080727A: Enhanced Swift-XRT position
  49. GRB 080727B: REM prompt observations
  50. GRB 080727B: Swift detection of a bright burst
  51. GRB 080727: Swift detection of a burst
  52. GRB 080723A: optical upper limit
  53. GRB080723B: Swift/UVOT Upper Limits
  54. GRB 080725: REM prompt observations
  55. ATCA radio upper limit on GRB 080723B
  56. GRB 080723A: Swift/UVOT Upper Limits
  57. VLA radio upper limit on GRB 080721
  58. GRB 080723, Swift-BAT refined analysis
  59. GRB 080723B: AGILE GRID and MCAL results
  60. GRB 080723: Enhanced Swift-XRT position
  61. GRB 080723: Swift detection of a burst
  62. GRB 080721: Enhanced Swift-XRT position
  63. GRB 080721: Swift detection of a burst with a bright optical counterpart.
  64. Trigger 317393: Swift detection of a possible GRB
  65. Trigger 317205: Swift detection of an outburst from XTE J1701-407
  66. GRB 080714: GROND confirmation of the optical/NIR afterglow
  67. GRB 080714: Swift/UVOT Detection of an Optical Afterglow
  68. GRB 080714: Enhanced Swift-XRT position
  69. GRB 080714: Swift-BAT refined analysis
  70. GRB 080714: Swift detection of a burst
  71. GRB 080702A: optical upper limit
  72. GRB 080603A: CrAO optical observations
  73. GRB 080702B: Swift XRT confirmation of the afterglow
  74. GRB 080710: Lick IR detection
  75. GRB 0800707: optical observations
  76. GRB 080710: Swift-XRT refined analysis
  77. GRB080710: Swift/UVOT observations
  78. GRB 080710: Enhanced Swift-XRT position
  79. UVOT white band observations of GRB080710
  80. GRB 080710: REM afterglow confirmation & brightening
  81. GRB 080710: Swift XRT position
  82. GRB 080707: possible break in the X-rays
  83. GRB 080707: GROND Confirmation of the Optical Afterglow
  84. UVOT observations of GRB080707
  85. GRB 080707: Swift XRT refined analysis
  86. GRB 080707: Enhanced Swift-XRT position
  87. GRB 080707: VLT redshift
  88. GRB 080707: GROND Detection of the Optical Afterglow Candidate
  89. GRB 080707: Swift detection of a burst
  90. Refined analysis of Swift Trigger 316063, is IGR J08408-4503
  91. Trigger 316063: Swift detection of a transient
  92. GRB 080703: GROND Upper Limits
  93. GRB 080702B: GROND Upper Limits
  94. GRB 080703: VLT observations of the afterglow
  95. GRB 080703: Enhanced Swift-XRT position
  96. GRB 080703: Swift detection of a burst with optical afterglow
  97. No radio detection from the short GRB 080702A
  98. Swift/UVOT observation of GRB080702A
  99. GRB 080702B: Swift XRT and UVOT observations
  100. GRB 080625: Suzaku WAM observation of the prompt emission

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