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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"

36214 results found.

  1. GRB 070612A: SARA detection of possible OT
  2. GRB 070612B: Swift XRT position from downlink data
  3. GRB 070610: TAROT Calern observatory optical observations
  4. GRB 070610: MITSuME OAO optical upper limit
  5. GRB 070612B: Swift detection of a burst
  6. GRB070612 - SDSS Pre-Burst Observations
  7. GRB 070612: Swift detection of a burst
  8. GRB 070610: OPTIMA-Burst detection of continued strong flaring activity
  9. GRB 070610: SARA upper limit
  10. GRB 070610: Swift-XRT refined analysis
  11. GRB 070610: TLS RRM sees flaring behaviour - Galactic transient?
  12. GRB 070611: Swift/UVOT Observations
  13. GRB 070611: Swift-XRT refined analysis
  14. GRB 070611, Swift-BAT refined analysis
  15. GRB 070610: Optical observations from OSN
  16. GRB 070610: Watcher Observations
  17. GRB 070611: VLT redshift
  18. GRB 060121 : pseudo-z = 1.9 ('intermediate-duration' burst)
  19. GRB 070611: ROTSE-III Detection of Late Rising Optical Counterpart
  20. GRB 070611; Swift-XRT position
  21. GRB 070611: ROTSE-III Optical Limits
  22. GRB 070611: Swift detection of a burst
  23. GRB 070610: Swift-UVOT Upper Limits
  24. GRB 070610: OPTIMA-Burst high-time-resolution optical observations
  25. GRB 070610, Swift-BAT refined analysis
  26. GRB 070610; Swift-XRT position
  27. GRB 070610: Swift detection of a burst
  28. GRB 070412: TAROT Calern observatory optical observations
  29. GRB 070411: TAROT Calern observatory optical observations
  30. GRB 070419A, deep LBT photometry and possible supernova detection
  31. GRB070520B: optical observations
  32. GRB070520: optical observation
  33. GRB070518: optical observation
  34. GRB070521: optical observation
  35. GRB 070531: NOT nIR observations
  36. GRB 070531: Swift-BAT refined analysis
  37. GRB 070531: I-band observations from IAC80
  38. GRB 070531: Swift-XRT position
  39. GRB 070531: Liverpool Telescope Optical Observations
  40. GRB 070531: Swift detection of a burst
  41. GRB 070529: SARA upper limit
  42. GRB 070529: MARGE Observations
  43. GRB 070529: Optical aterglow from MIRO
  44. GRB 070529: Gemini Redshift
  45. GRB 070529: Swift-XRT refined analysis
  46. GRB 070529, Swift-BAT refined analysis
  47. GRB 070529: Xinglong TNT Optical Upper Limit
  48. GRB 070529: Swift detection of a burst with an optical aterglow
  49. GRB 070412: Deep Keck imaging
  50. Swift trigger 280447 is probably a Galactic transient
  51. GRB 070518, deep LBT photometry
  52. GRB 070518: MARGE Observations
  53. GRB 070521: pseudo-z ~ 2.28 from prompt emission spectrum
  54. Konus-Wind observation of GRB 070521
  55. GRB 070518: optical observation
  56. GRB070520B: NIR observations
  57. GRB 070521: Swift/UVOT Upper Limits
  58. GRB 070521, optical observation
  59. GRB 070521: Swift-XRT refined analysis
  60. GRB 070521: Keck imaging
  61. GROND upper limits of GRB 070521
  62. GRB 070521 Milagro GeV/TeV Observations
  63. GRB 070520B: SARA upper limit
  64. GRB 070520A: SARA upper limit
  65. GRB 070521: SARA upper limit
  66. GRB 070521: Subaru observations and possible host detection
  67. GRB 070520B: Swift/UVOT Upper Limits
  68. GRB 070520A: Subaru Observations
  69. GRB 070521, Swift-BAT refined analysis
  70. GRB 070520A: Swift UVOT Upper Limits
  71. GRB 070520B: Swift-XRT refined analysis
  72. GRB 070521: optical limit by Pi of the Sky
  73. GRB070521 : Faulkes Telescope North Observations
  74. GRB 070521: TAROT La Silla observatory optical observations
  75. GRB070521: Bright SDSS Galaxy Near XRT Error Circle
  76. GRB070521 - SDSS Pre-Burst Observations
  77. GRB 070521: Swift detection of a burst
  78. GRB 070520A: MITSuME Akeno optical upper limits
  79. GRB 070520B, Swift-BAT refined analysis
  80. GRB 070520A, Swift-BAT refined analysis
  81. GRB 070520A: Swift-XRT refined analysis
  82. GRB 070518: TNG observations
  83. GRB 070520B: Swift detection of a burst
  84. GRB 070520: Xinglong EST optical Upper Limit
  85. GRB 070520: Swift detection of a burst
  86. VLA observation of GRB 070518
  87. GRB 070518: Swift-XRT refined analysis
  88. GRB 070517: Gemini optical imaging
  89. GRB070518: OSN observation
  90. GRB 070518, Swift-BAT refined analysis
  91. GRB 070518: OT confirmed form Xinglong TNT observation
  92. GRB 070518: Swift detection of a burst with optical afterglow
  93. GRB 070517, Swift-BAT refined analysis
  94. GRB 070517: Optical search
  95. GRB 070517: Swift detection of a burst
  96. GRB 070509: objects inside XRT error circle
  97. GRB 070512: pseudo-z ~ 1.39 from prompt emission spectrum
  98. GRB 070512: IPN localization and Konus spectrum of a bright burst
  99. GRB070419A: optical observations
  100. GRB 070419A, Deep LBT photometry

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