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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"

32511 results found.

  1. GRB010222: R-band data
  2. GRB010222 Optical observations
  3. GRB 010222: Keck Spectroscopy
  4. GRB010222 further R-band photometry
  5. GRB010222, possible increase of optical decay slope
  6. GRB010222: fading behavior
  7. GRB 010222 BV optical observations
  8. GRB010222 R-BAND OBSERVATION
  9. GRB 010220: Near-IR Observations
  10. GRB010214 follow-up from Hanle
  11. GRB 010222: Near-IR Observations
  12. GRB 010222: Optical Observations
  13. GRB 010222, Decay Slope Confirmed
  14. GRB010222: Another absorption line system
  15. GRB010222: Optical decay slope
  16. GRB 010214, Optical Observations
  17. GRB010222: Sub-millimeter detection
  18. GRB010222: R-band fading behavior
  19. GRB010222: Optical Observations
  20. GRB010222, radio observations
  21. GRB010222, optical observations
  22. GRB010222: BeppoSAX/NFI Observations
  23. Redshift of the Optical Transient of GRB010222
  24. GRB010222: possible optical counterpart
  25. GRB010222
  26. GRB010222: BeppoSAX refined position
  27. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  28. GRB010220, Radio and Optical Observations
  29. GRB 010220, simultaneous optical observations
  30. GRB010220: BeppoSAX WFC and GRBM preliminary data
  31. GRB010214, candidate optical afterglow
  32. GRB010214, optical observations
  33. GRB010214: BeppoSAX WFC and GRBM preliminary data
  34. GRB 010214: X-Ray afterglow
  35. GRB 010214, Optical Observations
  36. GRB 010214 optical observation
  37. GRB010213, Radio Observations
  38. GRB010213 Optical Observation
  39. GRB010213, Radio Observations
  40. J-Band Observation of GRB 010214.
  41. GRB010214, Radio Observations
  42. GRB010214, optical observations
  43. GRB010213, optical observations
  44. Possible InfraRed Transient of GRB 010214.
  45. GRB010214 Optical Observation
  46. GRB010213 (HETE) TAROT observations
  47. GRB 010214, optical observations
  48. IPN Status Report
  49. HETE Status
  50. GRB010126 opt. obs.
  51. IPN/RXTE TRIANGULATION OF GRB010126
  52. GRB010126: CONCAM crude optical limits during GRB
  53. GRB010126, TNG R-band observations
  54. GRB010126 Optical Observations
  55. GRB010126 optical observations
  56. GRB010126: Optical observations
  57. IPN/RXTE TRIANGULATION OF GRB010126
  58. GRB 010119, optical observations
  59. GRB010119: Optical observations
  60. Optical Observations of GRB 001018 at Keck
  61. GRB010119, Radio observations
  62. Optical observations of GRB 001018 with JCAM
  63. IPN TRIANGULATION OF GRB010109
  64. GRB 001204: Ks observations
  65. H band observation of GRB 001212
  66. GRB 001212 Optical Observation
  67. GRB 001212 Optical Observation
  68. GRB 001212 optical observation
  69. GRB 001212 possible OA in 2MASS
  70. GRB 001212 possible OA
  71. GRB001204: Optical observations
  72. Confirmation of IPN position for GRB001204
  73. GRB001204, Radio observations
  74. GRB 001105, further optical observations
  75. GRB001120: Gunn-i observations
  76. GRB001109, optical observations
  77. WSRT 4.8 GHz observations of GRB001109
  78. Optical/NIR observations of GRB001109
  79. GRB 001109: deep JHK upper limits
  80. GRB 001109 X-ray afterglow with BeppoSAX
  81. CORRECTION to XMM-Newton observation of GRB001025
  82. GRB001109: Optical observations
  83. GRB001109, R-band optical observations
  84. GRB001109, Radio observations
  85. GRB001105 BVRI field photometry correction
  86. GRB001105, BVRI field photometry
  87. GRB 001105, R-band observation
  88. GRB 991208: HST Imaging of the Host Galaxy
  89. GRB000926: R-image of the host galaxy
  90. GRB 001025B, I-band observations
  91. XMM-Newton observation of GRB001025
  92. GRB001025B, Radio observations
  93. GRB 001025 Optical Observations
  94. GRB 001025A, optical observation
  95. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  96. IPN triangulation of GRB001025
  97. GRB001007: Optical observations
  98. GRB001007, Radio observations
  99. GRB 001018, Possible Radio Afterglow
  100. CORRECTION TO PEAK FLUX OF GRB001018

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