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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"

25810 results found.

  1. Swift/UVOT Observations of GRB070707
  2. Swift XRT observation of GRB 070707
  3. GRB 070707: VLT observations
  4. GRB070704: FAVOR optical observations
  5. GRB 070704 : Liverpool Telescope Observations
  6. GRB 070611: VLT observations
  7. VLA detection of GRB 070612A in C Band
  8. GRB 070704: Swift-XRT refined analysis
  9. Swift/UVOT Observations of GRB070704
  10. GRB 070704, Swift-BAT refined analysis
  11. GRB 070704: Correction to GCN Circ 6594
  12. GRB 070704: Swift detection of a burst
  13. GRB 070626: Suzaku/WAM observation of the prompt emission
  14. GRB 070628 Swift-UVOT Refined Analysis
  15. GRB 070628: NIR detection of afterglow
  16. GRB 070628, Swift-BAT refined analysis
  17. GRB 070628: TAROT La Silla observatory optical observations
  18. Swift UVOT Observations of GRB 070628
  19. OT20050728 was not an optical GRB afterglow
  20. GRB 070616 : WIDGET simultaneous optical observations
  21. GRB 070616: Suzaku/WAM observation of the prompt emission
  22. GRB070621: RTT150 optical observations
  23. GRB 070621: VLT optical observations
  24. GRB 070621: Swift/UVOT Upper Limits
  25. Keck Laser Guide Star Adaptive Optics Imaging of GRB 070621
  26. GRB 070621: Swift-BAT refined analysis
  27. GRB070621: Swift XRT refined analysis
  28. GRB 070621: Gemini South optical imaging
  29. GRB 070621: UVOT-enhanced XRT position
  30. Observations of GRB070612A at Calar Alto
  31. GRB 070621: NOT observations
  32. GRB070621: OPTIMA-Burst optical upper limit
  33. GRB 070621: TAROT Calern observatory optical observations
  34. GRB 070621: Watcher Observations
  35. GRB 070621: Swift detection of a burst
  36. GMRT upper limit of GRB 070610/SWIFT J195509.6+261406 in 610 MHz
  37. Swift/UVOT detection of GRB070616 optical afterglow.
  38. GRB 070612A: NOT observations
  39. GRB070616: Optical Observation by MITSuME Okayama
  40. GRB 070616, Swift-BAT further refined analysis
  41. GRB 070616: BTA optical observations
  42. GRB 070616: TLS observation
  43. Swift XRT observations of the INTEGRAL burst GRB070615: Possible
  44. GRB 070616: Swift detection of a burst
  45. GRB 070612B: optical observations
  46. UVOT Observations of INTEGRAL burst GRB070615
  47. VLA upper limit on GRB 070610
  48. GRB 070615
  49. SWIFT J195509.6+261406 (GRB 070610): further observations
  50. GRB 070612A: Super-LOTIS observations
  51. GRB 070612A: Rapid Decay
  52. GRB 070612A: Suzaku/WAM observation of the prompt emission
  53. SWIFT J195509.6+261406 / GRB 070610: OPTIMA-Burst observations
  54. GRB070612A: MITSuME Okayama Observation
  55. GRB 070612A: continued SARA observations
  56. GRB 070611: Watcher Observations
  57. Swift Trigger 282176 is Cygnus X-1
  58. GRB 070612A: P60 Confirmation of Afterglow and An Underlying, Nearby
  59. GRB 070612B: SARA upper limit
  60. GRB 070612B, Swift-BAT refined analysis
  61. GRB 070612A, Swift-BAT refined analysis
  62. SWIFT J195509.6+261406 / GRB 070610: SWIFT continued observations
  63. GRB 070612B: Swift/UVOT upper limits
  64. GRB 070612B: FRAM limit
  65. GRB070612B: P60 Observations
  66. GRB 070612A: SARA detection of possible OT
  67. GRB 070610: TAROT Calern observatory optical observations
  68. GRB 070610: MITSuME OAO optical upper limit
  69. GRB070612 - SDSS Pre-Burst Observations
  70. GRB 070612: Swift detection of a burst
  71. GRB 070610: OPTIMA-Burst detection of continued strong flaring activity
  72. GRB 070610: SARA upper limit
  73. GRB 070610: Swift-XRT refined analysis
  74. GRB 070611: Swift/UVOT Observations
  75. GRB 070611: Swift-XRT refined analysis
  76. GRB 070611, Swift-BAT refined analysis
  77. GRB 070610: Optical observations from OSN
  78. GRB 070610: Watcher Observations
  79. GRB 070611: ROTSE-III Detection of Late Rising Optical Counterpart
  80. GRB 070611: ROTSE-III Optical Limits
  81. GRB 070610: Swift-UVOT Upper Limits
  82. GRB 070610: OPTIMA-Burst high-time-resolution optical observations
  83. GRB 070610, Swift-BAT refined analysis
  84. GRB 070412: TAROT Calern observatory optical observations
  85. GRB 070411: TAROT Calern observatory optical observations
  86. GRB070520B: optical observations
  87. GRB070520: optical observation
  88. GRB070518: optical observation
  89. GRB070521: optical observation
  90. GRB 070531: NOT nIR observations
  91. GRB 070531: Swift-BAT refined analysis
  92. GRB 070531: I-band observations from IAC80
  93. GRB 070531: Liverpool Telescope Optical Observations
  94. GRB 070529: SARA upper limit
  95. Swift/UVOT refined analysis of GRB070529
  96. GRB 070529: Optical aterglow from MIRO
  97. GRB 070529: Swift-XRT refined analysis
  98. GRB 070529, Swift-BAT refined analysis
  99. GRB 070529: Xinglong TNT Optical Upper Limit
  100. GRB 070529: Swift detection of a burst with an optical aterglow

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