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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"
  1. GRB 030329: Optical Afterglow Observations
  2. GRB 030329: precise position from Kyoto images
  3. GRB 030328 Optical Observations
  4. GRB030328: Decay index
  5. GRB 030328: Optical observations
  6. GRB 030328: optical observations
  7. GRB 030329: Optical afterglow fading
  8. GRB 030329 follow-up
  9. GRB 030329: Optical afterglow candidate
  10. GRB 030329: OT candidate
  11. GRB 030329: Optical afterglow candidate
  12. GRB 030328: OT photometry
  13. GRB030328: optical spectroscopy at TNG
  14. GRB030328: optical photometry at the TNG
  15. VLT spectra of GRB 030328
  16. GRB 030328, optical spectroscopy
  17. GRB 030328, optical observations
  18. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  19. GRB 030328: Optical observations
  20. Re: GRB 030328: Finding chart
  21. GRB 030328: Finding chart
  22. GRB 030328: Optical afterglow candidate
  23. GRB030323 optical observations
  24. GRB030324 optical observation
  25. GRB030131, BVRcIc field photometry
  26. Possible GRB030323 localized by INTEGRAL
  27. IPN triangulation of GRB030325 (final analysis)
  28. GRB030323: Detection on 2003/03/24
  29. IPN triangulation of GRB030326 (single small error box)
  30. GRB 030323: SARA Optical Observations
  31. IPN triangulation of GRB030325 (single small error box)
  32. GRB030324, optical observations
  33. GRB030324, optical observations
  34. IPN triangulation of GRB030325 (two small error boxes)
  35. GRB 030324: TAROT optical observations
  36. GRB030323: V, R, I photometry
  37. GRB 030324 (HETE #2641): Optical observations
  38. GRB030324, Optical Observations
  39. GRB030323: Upper limits from recent and historical observations.
  40. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  41. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  42. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  43. VLT/FORS2 spectra of GRB 030323
  44. GRB030323, ROTSE-III detection of possible optical counterpart
  45. GRB030323, optical observations
  46. GRB030324, BVRcIc field photometry
  47. GRB030323, possible optical counterpart
  48. GRB030323, BVRcIc field calibration
  49. GRB 030324 optical observations
  50. GRB 030320: Optical Observations
  51. GRB 030324, optical observations
  52. IPN triangulation of GRB030320B (annulus)
  53. IPN triangulation of GRB030320 (small error box)
  54. IPN triangulation of GRB030320
  55. Possible GRB 030320 localized by INTEGRAL
  56. GRB030226, addendum to GCN 1892
  57. IPN upper limit to a GRB associated with SN2003L
  58. IPN triangulation of GRB030317 (annulus)
  59. IPN triangulation of GRB030307 (annulus)
  60. GRB 030227: Optical limit at RIKEN
  61. GRB 030226 Optical observations
  62. IPN triangulation of GRB030306 (single small error box - REVISED)
  63. GRB030226: Optical observations at Asiago
  64. IPN triangulation of GRB030306 (single small error box)
  65. IPN triangulation of GRB030306 (two small error boxes)
  66. IPN triangulation of GRB030306 (intense; annulus only so far)
  67. GRB 030226: Optical observations
  68. GRB030226: Analysis of Chandra data
  69. IPN triangulation of GRB030304 (annulus)
  70. GRB 030227: Optical observations
  71. GRB030226, BVRc observations
  72. Chandra detection of the X-ray afterglow of GRB 030226
  73. GRB 030226, further optical/NIR imaging
  74. GRB030227, optical observations
  75. GRB 030226: Ic Observations
  76. GRB030227: Kiso optical upper limit
  77. IPN triangulation of GRB030301 (annulus)
  78. IPN triangulation of GRB030228 (annulus)
  79. GRB030227, BVRcIc field photometry
  80. GRB030226, BVRcIc field calibration
  81. GRB 030227 optical afterglow
  82. 030302: NOT A GRB
  83. 030228: NOT A GRB
  84. GRB 030228, optical observations
  85. GRB 030226: Steep Decline
  86. GRB 030227: Confirmed Optical Afterglow (S1-A)
  87. GRB 030226: R band polarimetric observations
  88. GRB 030226: Optical observations
  89. GRB 030227: fading of candidate optical afterglow 'S1-A'
  90. GRB030227:Optical observations
  91. GRB 20030226: Upper limits from recent and historical observations
  92. GRB 030227, possible optical counterpart of XMM-Newton source
  93. GRB030227 - faint tentative OT candidate
  94. GRB 030226, optical observations
  95. XMM-Newton observation of GRB030227
  96. GRB030227: Kiso optical observations
  97. GRB 030227: Kyoto optical observation
  98. GRB 030226, optical light curve
  99. GRB 030226 spectroscopy
  100. GRB030227: refined INTEGRAL position

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