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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"
  1. GRB 120728A: Swift-XRT refined Analysis
  2. GRB 120728A: Enhanced Swift-XRT position
  3. Trigger 529076: Swift possible detection of SwJ1910.2-0546
  4. GRB 120728A: GROND observations
  5. GRB 120728A: Swift detection of a burst
  6. GRB 120727A/Galactic source: Fermi-LAT detection of a transient source
  7. GRB 120716A: optical observation in Maidanak observatory
  8. Swift Trigger 528925 is probably a noise fluctuation
  9. GRB 120722A: optical upper limit
  10. GRB 120724A: optical observation in Maidanak observatory
  11. GRB 120724A: JCMT SCUBA-2 sub-mm observation
  12. GRB 120716A: optical observation in CrAO
  13. GRB 120724A, Swift-BAT refined analysis
  14. GRB 120724A: Swift/UVOT Detection of the Optical Afterglow
  15. GRB 120724A: Enhanced Swift-XRT position
  16. GRB 120724A: Swift-XRT refined Analysis
  17. GRB120711A: Planned XMM-Newton observation
  18. GRB 120724A: Gemini-N tentative redshift
  19. GRB 120724A: FTN optical afterglow candidate
  20. GRB 120724A: Swift detection of a burst
  21. GRB 120709A: Swift re-observation of the field of the X-ray counterpart candidate.
  22. GRB 120722A: Swift/UVOT Upper Limits
  23. GRB 120722A: VLT/X-shooter redshift of the host galaxy
  24. GRB 120722A: GROND detection of the afterglow
  25. GRB 120722A: 1.5m OSN I-band observations
  26. GRB 120722A: Swift-XRT refined Analysis
  27. GRB 120722A: Swift-BAT refined analysis
  28. GRB 120722A: Enhanced Swift-XRT position
  29. GRB 120722A: Correction for GCN circ.13500
  30. GRB 120722A: Xinglong TNT optical afterglow candidate
  31. GRB 120722A: Swift detection of a burst
  32. GRB 120716A: Fermi GBM observation
  33. GRB 120716A: EVLA Detection
  34. GRB 120716A: Swift-XRT detection
  35. GRB 120716A: Swift/XRT position consistent with that of the optical counterpart
  36. GRB 120716A: Redshift confirmation from VLT/X-shooter
  37. VLT/FORS2 redshift of GRB120716A
  38. GRB 120716A: GROND confirmation of the optical/NIR afterglow
  39. GRB 120716A: Typo correction in GCN 13490
  40. GRB 120716A: Optical decay from NOT
  41. GRB 120716A: Candidate Optical Afterglow from PTF
  42. Konus-Wind observation of GRB 120716A
  43. IPN Triangulation of unusual GRB 120716A
  44. Fermi GBM trigger 120716.498 is not a GRB
  45. GRB 120711A: ATCA 34GHz final observations (upper limit)
  46. GRB 120714B: Swift/UVOT Detection
  47. GRB 120714B: Swift-XRT refined Analysis
  48. GRB120714A: Swift/UVOT upper limits
  49. GRB 120714B: Swift-BAT refined analysis
  50. Swift-BAT refined analysis of 1E 1841-045 (Trigger=526660)
  51. GRB 120714A: GROND upper limits
  52. GRB 120714B: GROND confirmation of fading afterglow
  53. GRB 120714B: Redshift from VLT/X-shooter
  54. GRB 120714A: Swift-XRT refined Analysis
  55. Trigger 526660: Swift detection of 1 E 1841-045 (aka Kes 73)
  56. GRB 120624B: VLA Observations
  57. GRB 120714B: Position Correction and Candidate Optical Afterglow
  58. GRB 120714A: Swift-BAT refined analysis
  59. GRB 120714B: Swift detection of a burst
  60. GRB 120714A: Enhanced Swift-XRT position
  61. GRB 120712A: Fermi GBM observation
  62. GRB 120711A: INTEGRAL/SPI observations
  63. GRB120714A: UVOT non-detection
  64. GRB 120714A: Swift-XRT observations
  65. GRB120711B: MITSuME Ishigakijima upper limits
  66. GRB 120714A: Swift detection of a burst
  67. GRB 120711A: ATCA 34GHz further observations (upper limit)
  68. IPN Triangulation of GRB 120709A
  69. GRB 120712A: Swift/UVOT Detection
  70. GRB 120712A: VLT/Xshooter redshift
  71. GRB 120712A: Swift-XRT refined Analysis
  72. GRB 120712A Gemini-S redshift
  73. GRB 120712A: GROND Detection of the Optical/NIR Afterglow Candidate and photo-z
  74. GRB 120712A: Enhanced Swift-XRT position
  75. GRB 120712A: Swift-BAT refined analysis
  76. GRB 120712A: Swift detection of a burst with optical afterglow
  77. GRB 120711B: Swift-XRT refined Analysis
  78. GRB 120711A: Fermi LAT Detection
  79. GRB 120711A: ATCA 34GHz upper limit
  80. GRB 120711B: Swift-BAT refined analysis
  81. GRB 120711B: Swift/UVOT Upper Limits
  82. GRB 120711A: Swift/UVOT Observations
  83. GRB 120709A: Swift/UVOT Observations
  84. Konus-Wind observation of GRB 120711A
  85. GRB 120711A: Fermi LAT detection
  86. GRB 120711A: MASTER early OT detection
  87. GRB 120711A: Swift-XRT observations
  88. GRB 120711A Gemini-S likely redshift
  89. Konus-Wind observation of GRB 120709A
  90. GRB 120711A: REM NIR early time detection
  91. GRB 120711A: GROND photometric redshift
  92. GRB 120711A: Fermi GBM observation
  93. GRB 120711A: MAXI/GSC detection
  94. GRB 120711A: a possible X-ray transient
  95. GRB 120711A: an bright long GRB detected with INTEGRAL
  96. Continued Skynet/PROMPT observations of GRB120711A
  97. GRB 120711A: ROTSE-III confirm of Optical Counterpart
  98. Swift detection of GRB 120711B or a new Galactic transient
  99. Skynet/PROMPT Observations of GRB120711A
  100. GRB 120709A: Fermi GBM detection

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Download all Circulars as a .tar.gz archive (updated once a day):
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