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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"

45722 results found.

  1. GRB030227: Kiso optical upper limit
  2. IPN triangulation of GRB030301 (annulus)
  3. IPN triangulation of GRB030228 (annulus)
  4. GRB030227, BVRcIc field photometry
  5. GRB030226, BVRcIc field calibration
  6. GRB 030227 optical afterglow
  7. 030302: NOT A GRB
  8. 030228: NOT A GRB
  9. GRB 030228, optical observations
  10. GRB 030226: Steep Decline
  11. GRB 030227: Confirmed Optical Afterglow (S1-A)
  12. GRB 030226: R band polarimetric observations
  13. GRB 030226: Optical observations
  14. GRB 030227: fading of candidate optical afterglow 'S1-A'
  15. GRB030227:Optical observations
  16. GRB 20030226: Upper limits from recent and historical observations
  17. GRB 030227, possible optical counterpart of XMM-Newton source
  18. GRB030227 - faint tentative OT candidate
  19. GRB 030226, optical observations
  20. XMM-Newton observation of GRB030227
  21. GRB030227: Kiso optical observations
  22. GRB 030227: Kyoto optical observation
  23. GRB 030226, optical light curve
  24. GRB 030226 spectroscopy
  25. GRB030227: refined INTEGRAL position
  26. GRB030227 localized by INTEGRAL
  27. Possible break in the GRB 030226 light curve
  28. GRB 030226 : Predicted light curve
  29. GRB030226: optical observation
  30. IPN triangulation of GRB030225 (annulus)
  31. GRB 030226: Confirmed decay index
  32. GRB030226: ESI spectroscopy
  33. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  34. GRB 030226 simultaneous optical observations
  35. Two absorption systems in GRB 030226
  36. GRB 030226, optical observations
  37. GRB030226: optical observations and refined redshift
  38. GRB030226: Optical decay index
  39. GRB 030226 Optical Spectra and R,I,z' Imaging
  40. GRB 030226, optical observations
  41. GRB 030226: Optical afterglow
  42. GRB030226: Candidate optical afterglow
  43. GRB 030217: Optical Observations at 4, 5, and 6 Days
  44. IPN triangulation of GRB030223 (annulus)
  45. IPN triangulation of GRB030220 (annulus)
  46. GRB: Non-Referencing of GCN Circulars.
  47. IPN triangulation of GRB030218 (annulus)
  48. GRB030217: optical observations
  49. IPN triangulation of GRB030217 (small error box)
  50. IPN triangulation of GRB030215C (annulus)
  51. IPN triangulation of GRB030217 (annulus)
  52. IPN triangulation of GRB030216 (annulus)
  53. IPN triangulation of GRB030215A and GRB030215B (annuli)
  54. GRB030115, WSRT radio observations - correction to GCN 1864
  55. GRB 030131: marginal optical detection
  56. GCN/INTEGRAL Mistake Fixed
  57. GRB030115, WSRT radio observations
  58. IPN triangulation of GRB030206 (annulus)
  59. IPN triangulation of GRB030208 (annulus)
  60. GRB 030204: Optical Observations
  61. GRB030204 field photometry
  62. GRB020819: Kiso R and I band observations
  63. GRB 030204: Correction to GCN 1856
  64. GRB030131: Candidate Optical Afterglow
  65. GRB 030115: Optical Observations
  66. GRB 030204, optical observations
  67. IPN triangulation of GRB030204 (small error box)
  68. IPN triangulation of GRB030202 (annulus)
  69. GRB 030131, optical observations
  70. GRB030131: Kiso optical limit for corrected position
  71. GRB030131: Optical limits for corrected position
  72. GRB 030131: afterglow candidate
  73. GRB 030115, late-time optical observations
  74. GRB030131: corrected INTEGRAL position
  75. Type Ic SN2003L (SN/GRB?), optical spectrum
  76. GRB030131: Kiso Observations
  77. GRB 020819: Host galaxy at Radio Position
  78. IPN triangulation of GRB030131 - CORRECTION
  79. GRB 020819: afterglow candidate
  80. IPN triangulation of GRB030131
  81. GRB030131: Optical limit
  82. GRB 030131 optical observations
  83. GRB030131: refined position
  84. GRB 030131 optical observations
  85. A long GRB detected by INTEGRAL
  86. GRB030115: 1.2 mm upper limits with MAMBO @ IRAM 30m
  87. Type Ic SN2003L (SN/GRB?) Radio Observations
  88. IPN triangulation of GRB030127 (annulus)
  89. GRB030115 submm upper limit
  90. IPN triangulation of GRB030119 (two large error boxes)
  91. GRB 030115: Further IR observations with IRSF/SIRIUS
  92. IPN triangulation of GRB030117 (two large error boxes)
  93. Publicizing GRB Discoveries - A Message from NASA HQ
  94. GRB 030115: Radio detection of IR candidate
  95. GRB 030115, simultaneous observations by BOOTES-1
  96. GRB 030115: IR observations with IRSF/SIRIUS
  97. IPN triangulation of GRB030115C (large error box)
  98. GRB030115: R-band counterpart of IR candidate
  99. GRB030115, afterglow candidate
  100. GRB 021211: R-band observations at late-time

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