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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. GRB030227 localized by INTEGRAL
  2. Possible break in the GRB 030226 light curve
  3. GRB 030226 : Predicted light curve
  4. GRB030226: optical observation
  5. IPN triangulation of GRB030225 (annulus)
  6. GRB 030226: Confirmed decay index
  7. GRB030226: ESI spectroscopy
  8. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  9. GRB 030226 simultaneous optical observations
  10. Two absorption systems in GRB 030226
  11. GRB 030226, optical observations
  12. GRB030226: optical observations and refined redshift
  13. GRB030226: Optical decay index
  14. GRB 030226 Optical Spectra and R,I,z' Imaging
  15. GRB 030226, optical observations
  16. GRB 030226: Optical afterglow
  17. GRB030226: Candidate optical afterglow
  18. GRB 030217: Optical Observations at 4, 5, and 6 Days
  19. IPN triangulation of GRB030223 (annulus)
  20. IPN triangulation of GRB030220 (annulus)
  21. GRB: Non-Referencing of GCN Circulars.
  22. IPN triangulation of GRB030218 (annulus)
  23. GRB030217: optical observations
  24. IPN triangulation of GRB030217 (small error box)
  25. IPN triangulation of GRB030215C (annulus)
  26. IPN triangulation of GRB030217 (annulus)
  27. IPN triangulation of GRB030216 (annulus)
  28. IPN triangulation of GRB030215A and GRB030215B (annuli)
  29. GRB030115, WSRT radio observations - correction to GCN 1864
  30. GRB 030131: marginal optical detection
  31. GCN/INTEGRAL Mistake Fixed
  32. GRB030115, WSRT radio observations
  33. IPN triangulation of GRB030206 (annulus)
  34. IPN triangulation of GRB030208 (annulus)
  35. GRB 030204: Optical Observations
  36. GRB030204 field photometry
  37. GRB020819: Kiso R and I band observations
  38. GRB 030204: Correction to GCN 1856
  39. GRB030131: Candidate Optical Afterglow
  40. GRB 030115: Optical Observations
  41. GRB 030204, optical observations
  42. IPN triangulation of GRB030204 (small error box)
  43. IPN triangulation of GRB030202 (annulus)
  44. GRB 030131, optical observations
  45. GRB030131: Kiso optical limit for corrected position
  46. GRB030131: Optical limits for corrected position
  47. GRB 030131: afterglow candidate
  48. GRB 030115, late-time optical observations
  49. GRB030131: corrected INTEGRAL position
  50. Type Ic SN2003L (SN/GRB?), optical spectrum
  51. GRB030131: Kiso Observations
  52. GRB 020819: Host galaxy at Radio Position
  53. IPN triangulation of GRB030131 - CORRECTION
  54. GRB 020819: afterglow candidate
  55. IPN triangulation of GRB030131
  56. GRB030131: Optical limit
  57. GRB 030131 optical observations
  58. GRB030131: refined position
  59. GRB 030131 optical observations
  60. A long GRB detected by INTEGRAL
  61. GRB030115: 1.2 mm upper limits with MAMBO @ IRAM 30m
  62. Type Ic SN2003L (SN/GRB?) Radio Observations
  63. IPN triangulation of GRB030127 (annulus)
  64. GRB030115 submm upper limit
  65. IPN triangulation of GRB030119 (two large error boxes)
  66. GRB 030115: Further IR observations with IRSF/SIRIUS
  67. IPN triangulation of GRB030117 (two large error boxes)
  68. Publicizing GRB Discoveries - A Message from NASA HQ
  69. GRB 030115: Radio detection of IR candidate
  70. GRB 030115, simultaneous observations by BOOTES-1
  71. GRB 030115: IR observations with IRSF/SIRIUS
  72. IPN triangulation of GRB030115C (large error box)
  73. GRB030115: R-band counterpart of IR candidate
  74. GRB030115, afterglow candidate
  75. GRB 021211: R-band observations at late-time
  76. GRB030115: Optical Observations, Swiss Telescope at La Silla (ESO, Chile)
  77. IPN triangulation of GRB030115B (small error box)
  78. GRB 030115 : Possible IR counterpart
  79. GRB 030115: Radio Observations
  80. GRB030115 (=H2533): A Long GRB Localized by the HETE WXM and SXC
  81. Distribution of INTEGRAL SPI-ACS triggers for GRB bursts
  82. IPN triangulation of GRB030115B (annulus)
  83. ANNOUNCEMENT ON INTEGRAL GRB ALERTS
  84. Distribution of INTEGRAL SPI-ACS triggers
  85. GRB030115: R-band observations at Asiago
  86. GRB030115: TAROT optical observations
  87. GRB 021211: VLT spectrum
  88. GRB 030115: APO Optical Observations
  89. GRB 030115, no optical candidate
  90. GRB 030115, optical observations
  91. GRB 030115, optical candidate
  92. Possible GRB030113 seen by SPI ACS
  93. Probable GRB030112B seen by SPI ACS
  94. Probable GRB030112 seen by SPI ACS
  95. Information about where HETE will be pointing
  96. Possible GRB030111 seen by SPI ACS
  97. Possible GRB030110b seen by SPI ACS
  98. Possible GRB 030110 seen by SPI ACS
  99. IPN triangulation of GRB030109 (annulus)
  100. IPN triangulation of GRB030105 (large error box)

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