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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"

25040 results found.

  1. GRB 070721B: optical observations and proposed redshift
  2. GRB 070721B, Further Swift-BAT refined analysis
  3. Swift/UVOT Observations of GRB070721A
  4. GRB 070721B : Faulkes Telescope South observations
  5. GRB 070721B: Swift-XRT refined analysis
  6. GRB 070721A : Faulkes Telescope South optical limit
  7. GRB 070721A: Swift/XRT refined analysis
  8. GRB 070721B, Swift-BAT refined analysis
  9. GRB 070721A, Swift-BAT refined analysis
  10. GRB070721B: A bright UVOT candidate
  11. GRB 070714B: Swift/BAT and Suzaku/WAM joint spectral analysis
  12. GRB 070714B : Suzaku WAM observation of the prompt emission
  13. GRB070714B: TNG NIR observations
  14. Erratum : Suzaku WAM observation of GRB 070704
  15. GRB 070714A: Swift/UVOT Upper limits
  16. GRB 070714B: Swift/UVOT Upper Limits
  17. GRB 070714B: confirmation of optical afterglow
  18. GRB 070616: No Evidence for I Band Afterglow
  19. GRB 070714A: Swift XRT refined analysis
  20. GRB070714B: Swift-XRT refined analysis
  21. GRB 070707: Swift-XRT follow-up observations
  22. GRB 070714B, Swift-BAT refined analysis of the short hard burst
  23. GRB 070714A, Swift-BAT refined analysis
  24. GRB 070714 : Liverpool Telescope optical counterpart ?
  25. GRB 070714: Swift detection of a bright burst, possibly short
  26. SN 2007bg - off-axis GRB?
  27. GRB 070704: RTT150 optical observations
  28. GRB 070704: Suzaku/WAM observation of the prompt emission
  29. Konus-Wind observation of GRB 070707
  30. GRB 070707: optical afterglow
  31. Swift/UVOT Observations of GRB070707
  32. Swift XRT observation of GRB 070707
  33. GRB 070707: VLT observations
  34. GRB070704: FAVOR optical observations
  35. GRB 070704 : Liverpool Telescope Observations
  36. GRB 070611: VLT observations
  37. VLA detection of GRB 070612A in C Band
  38. GRB 070704: Swift-XRT refined analysis
  39. Swift/UVOT Observations of GRB070704
  40. GRB 070704, Swift-BAT refined analysis
  41. GRB 070704: Correction to GCN Circ 6594
  42. GRB 070704: Swift detection of a burst
  43. GRB 070626: Suzaku/WAM observation of the prompt emission
  44. GRB 070628 Swift-UVOT Refined Analysis
  45. GRB 070628: NIR detection of afterglow
  46. GRB 070628, Swift-BAT refined analysis
  47. GRB 070628: TAROT La Silla observatory optical observations
  48. Swift UVOT Observations of GRB 070628
  49. OT20050728 was not an optical GRB afterglow
  50. GRB 070616 : WIDGET simultaneous optical observations
  51. GRB 070616: Suzaku/WAM observation of the prompt emission
  52. GRB070621: RTT150 optical observations
  53. GRB 070621: VLT optical observations
  54. GRB 070621: Swift/UVOT Upper Limits
  55. Keck Laser Guide Star Adaptive Optics Imaging of GRB 070621
  56. GRB 070621: Swift-BAT refined analysis
  57. GRB070621: Swift XRT refined analysis
  58. GRB 070621: Gemini South optical imaging
  59. GRB 070621: UVOT-enhanced XRT position
  60. Observations of GRB070612A at Calar Alto
  61. GRB 070621: NOT observations
  62. GRB070621: OPTIMA-Burst optical upper limit
  63. GRB 070621: TAROT Calern observatory optical observations
  64. GRB 070621: Watcher Observations
  65. GRB 070621: Swift detection of a burst
  66. GMRT upper limit of GRB 070610/SWIFT J195509.6+261406 in 610 MHz
  67. Swift/UVOT detection of GRB070616 optical afterglow.
  68. GRB 070612A: NOT observations
  69. GRB070616: Optical Observation by MITSuME Okayama
  70. GRB 070616, Swift-BAT further refined analysis
  71. GRB 070616: BTA optical observations
  72. GRB 070616: TLS observation
  73. Swift XRT observations of the INTEGRAL burst GRB070615: Possible
  74. GRB 070616: Swift detection of a burst
  75. GRB 070612B: optical observations
  76. UVOT Observations of INTEGRAL burst GRB070615
  77. VLA upper limit on GRB 070610
  78. GRB 070615
  79. SWIFT J195509.6+261406 (GRB 070610): further observations
  80. GRB 070612A: Super-LOTIS observations
  81. GRB 070612A: Rapid Decay
  82. GRB 070612A: Suzaku/WAM observation of the prompt emission
  83. SWIFT J195509.6+261406 / GRB 070610: OPTIMA-Burst observations
  84. GRB070612A: MITSuME Okayama Observation
  85. GRB 070612A: continued SARA observations
  86. GRB 070611: Watcher Observations
  87. Swift Trigger 282176 is Cygnus X-1
  88. GRB 070612A: P60 Confirmation of Afterglow and An Underlying, Nearby
  89. GRB 070612B: SARA upper limit
  90. GRB 070612B, Swift-BAT refined analysis
  91. GRB 070612A, Swift-BAT refined analysis
  92. SWIFT J195509.6+261406 / GRB 070610: SWIFT continued observations
  93. GRB 070612B: Swift/UVOT upper limits
  94. GRB 070612B: FRAM limit
  95. GRB070612B: P60 Observations
  96. GRB 070612A: SARA detection of possible OT
  97. GRB 070610: TAROT Calern observatory optical observations
  98. GRB 070610: MITSuME OAO optical upper limit
  99. GRB070612 - SDSS Pre-Burst Observations
  100. GRB 070612: Swift detection of a burst

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