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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.

Lucene Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

3036 results found.

  1. GRB 080328: Swift XRT refined analysis
  2. GRB 080325: Subaru detection of NIR afterglow candidate
  3. GRB080325: XRT Refined Analysis
  4. GRB 080319D: Swift XRT refined analysis
  5. GRB 080319B: Swift-XRT Team Refined Analysis
  6. Swift trigger 306323: Swift-BAT/XRT refined analysis
  7. GRB 080310: Swift/UVOT Refined Analysis
  8. GRB 080307: Swift-XRT Team refined analysis
  9. Swift UVOT observations of GRB080229B
  10. GRB080229B: Swift XRT afterglow observation
  11. GRB080229: Swift XRT refined analysis
  12. ESO optical and NIR observations of GRB 080218B
  13. GRB 080218B: Swift-XRT refined analysis
  14. GRB 080212: Swift-XRT Team refined analysis
  15. GRB 080207: Swift-XRT Refined Analysis
  16. GRB 080205: Swift XRT refined analysis
  17. GRB 080130: further Swift XRT observations confirm fading source
  18. GRB 080129: Swift-XRT refined analysis
  19. GRB 080121: Upper limit on X-ray afterglow
  20. SNe 2008D and 2007uy: Chandra Detections
  21. GRB 080123: Swift-XRT refined analysis
  22. GRB 080120: Swift-XRT refined analysis
  23. GRB080120: Swift XRT position
  24. Swift observations of the X-ray transient in NGC 2770 (aka SN2008D)
  25. Refined Swift-XRT analysis of the transient in NGC 2770
  26. GRB 071122 Swift-XRT refined analysis
  27. GRB 071117: Swift-XRT revised position
  28. Swift XRT follow-up observations of GRB071008
  29. GRB071118: Swift XRT refined analysis
  30. GRB 071117: Swift-XRT refined analysis
  31. GRB 071112C: Optical and NIR data observed with KANATA
  32. GRB 071112C: Swift XRT refined analysis
  33. GRB 071112B: Swift-XRT preliminary analysis
  34. Swift XRT follow-up observations of GRB071028B
  35. GRB 071109: further Swift-XRT analysis
  36. GRB 071109: Swift-XRT possible X-ray counterpart
  37. GRB 071104: Swift-XRT Team Refined Analysis
  38. GRB 071104: Possible Swift UVOT Afterglow Candidate
  39. GRB 071104: Swift-XRT position
  40. Swift XRT and UVOT observations of GRB071028B
  41. GRB071101: Optical and NIR upper limits by KANATA
  42. GRB 071101: Swift XRT position
  43. GRB 071031: Swift-XRT Team refined analysis
  44. GRB 071028: Swift-XRT Team refined analysis
  45. GRB 071025A: Complex Early-Time IR Behavior, Simultaneous with Gamma- and X-rays
  46. GRB 071025: Swift-XRT Team refined analysis
  47. GRB071021 : CFHT Ks-band observation
  48. GRB 071021: (Relatively shallow) IR non-detections; motivation for optical spectroscopy
  49. GRB 071021: Swift-XRT Team refined analysis
  50. GRB 071018: Swift-XRT observation
  51. GRB 071017 - Swift XRT observations
  52. GRB 071011: Swift-XRT refined analysis
  53. GRB 071010: Swift-XRT observation
  54. GRB071008: Swift-XRT observation
  55. GRB 071003: XRT refined analysis
  56. GRB 070810B: further XRT analysis
  57. GRB 071003: Swift XRT position
  58. GRB 071001: Swift-XRT Team refined analysis
  59. GRB070925: Swift-XRT Position
  60. GRB 070920B: XRT observations
  61. GRB 070923: Galaxies within BAT localization
  62. INTEGRAL ToO observations of SGR1806-20
  63. GRB 070917: Confirmation of the X-ray afterglow
  64. GRB 070917: Swift-XRT observations
  65. GRB 070913: Swift-XRT detection of the possible X-ray afterglow
  66. GRB 070911: PAIRITEL IR Observations
  67. GRB 070911: Swift XRT refined analysis
  68. GRB 070731: Swift/UVOT Upper Limit
  69. GRB 070810B: XRT refined analysis
  70. GRB 070810: Swift-XRT Team Refined Analysis
  71. GRB 070809: Swift-XRT refined analysis
  72. GRB 070805: Swift XRT initial analysis.
  73. GRB 070724B: Swift-XRT afterglow confirmation
  74. GRB 070802: Swift-XRT refined analysis
  75. GRB 070802: GROND J band candidate
  76. GRB 070729: Swift-XRT refined analysis
  77. GRB 070729: Magellan NIR Observations
  78. GRB 070724: P60 and Gemini Observations
  79. GRB 070724: Swift-XRT Team refined analysis
  80. GRB 070721A: Swift/XRT refined analysis
  81. GRB 070714A: Swift XRT refined analysis
  82. GRB070714B: Swift-XRT refined analysis
  83. GRB 070707: Swift-XRT follow-up observations
  84. Swift XRT observation of GRB 070707
  85. GRB 070628: Swift XRT refined analysis
  86. GRB070621: Swift XRT refined analysis
  87. GRB 070616: Swift XRT refined circular
  88. GRB 070612B: Swift-XRT refined analysis
  89. SWIFT J195509.6+261406 / GRB 070610: SWIFT continued observations
  90. GRB 070610: Swift-XRT refined analysis
  91. GRB 070611: Swift-XRT refined analysis
  92. GRB 070611; Swift-XRT position
  93. GRB 070610; Swift-XRT position
  94. GRB 070529: Swift-XRT refined analysis
  95. GRB 070521: Swift-XRT refined analysis
  96. GRB070521: Gemini Observations
  97. GROND upper limits of GRB 070521
  98. GRB 070520B: Swift-XRT refined analysis
  99. GRB 070520A: Swift-XRT refined analysis
  100. GRB 070518: Swift-XRT refined analysis

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