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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"

36132 results found.

  1. GRB 030227 optical afterglow
  2. 030302: NOT A GRB
  3. 030228: NOT A GRB
  4. GRB 030228, optical observations
  5. GRB 030226: Steep Decline
  6. GRB 030227: Confirmed Optical Afterglow (S1-A)
  7. GRB 030226: R band polarimetric observations
  8. GRB 030226: Optical observations
  9. GRB 030227: fading of candidate optical afterglow 'S1-A'
  10. GRB030227:Optical observations
  11. GRB 20030226: Upper limits from recent and historical observations
  12. GRB 030227, possible optical counterpart of XMM-Newton source
  13. GRB030227 - faint tentative OT candidate
  14. GRB 030226, optical observations
  15. GRB030227: Kiso optical observations
  16. GRB 030227: Kyoto optical observation
  17. GRB 030226, optical light curve
  18. GRB 030226 spectroscopy
  19. Possible break in the GRB 030226 light curve
  20. GRB 030226 : Predicted light curve
  21. IPN triangulation of GRB030225 (annulus)
  22. GRB 030226: Confirmed decay index
  23. GRB030226: ESI spectroscopy
  24. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  25. GRB 030226 simultaneous optical observations
  26. Two absorption systems in GRB 030226
  27. GRB 030226, optical observations
  28. GRB 030226 Optical Spectra and R,I,z' Imaging
  29. GRB 030226, optical observations
  30. GRB 030226: Optical afterglow
  31. GRB 030217: Optical Observations at 4, 5, and 6 Days
  32. IPN triangulation of GRB030223 (annulus)
  33. IPN triangulation of GRB030220 (annulus)
  34. GRB: Non-Referencing of GCN Circulars.
  35. IPN triangulation of GRB030218 (annulus)
  36. IPN triangulation of GRB030217 (small error box)
  37. IPN triangulation of GRB030215C (annulus)
  38. IPN triangulation of GRB030217 (annulus)
  39. IPN triangulation of GRB030216 (annulus)
  40. IPN triangulation of GRB030215A and GRB030215B (annuli)
  41. GRB030115, WSRT radio observations - correction to GCN 1864
  42. GRB 030131: marginal optical detection
  43. GRB030115, WSRT radio observations
  44. IPN triangulation of GRB030206 (annulus)
  45. IPN triangulation of GRB030208 (annulus)
  46. GRB 030204: Optical Observations
  47. GRB030204 field photometry
  48. GRB020819: Kiso R and I band observations
  49. GRB 030204: Correction to GCN 1856
  50. GRB 030115: Optical Observations
  51. GRB 030204, optical observations
  52. IPN triangulation of GRB030204 (small error box)
  53. IPN triangulation of GRB030202 (annulus)
  54. GRB 030131, optical observations
  55. GRB030131: Kiso optical limit for corrected position
  56. GRB030131: Optical limits for corrected position
  57. GRB 030131: afterglow candidate
  58. GRB 030115, late-time optical observations
  59. GRB030131: corrected INTEGRAL position
  60. Type Ic SN2003L (SN/GRB?), optical spectrum
  61. GRB030131: Kiso Observations
  62. GRB 020819: Host galaxy at Radio Position
  63. IPN triangulation of GRB030131 - CORRECTION
  64. GRB 020819: afterglow candidate
  65. IPN triangulation of GRB030131
  66. GRB 030131 optical observations
  67. GRB 030131 optical observations
  68. A long GRB detected by INTEGRAL
  69. GRB030115: 1.2 mm upper limits with MAMBO @ IRAM 30m
  70. Type Ic SN2003L (SN/GRB?) Radio Observations
  71. IPN triangulation of GRB030127 (annulus)
  72. GRB030115 submm upper limit
  73. IPN triangulation of GRB030119 (two large error boxes)
  74. GRB 030115: Further IR observations with IRSF/SIRIUS
  75. IPN triangulation of GRB030117 (two large error boxes)
  76. Publicizing GRB Discoveries - A Message from NASA HQ
  77. GRB 030115: Radio detection of IR candidate
  78. GRB 030115, simultaneous observations by BOOTES-1
  79. GRB 030115: IR observations with IRSF/SIRIUS
  80. IPN triangulation of GRB030115C (large error box)
  81. GRB030115: R-band counterpart of IR candidate
  82. GRB030115, afterglow candidate
  83. GRB 021211: R-band observations at late-time
  84. GRB030115: Optical Observations, Swiss Telescope at La Silla (ESO, Chile)
  85. IPN triangulation of GRB030115B (small error box)
  86. GRB 030115 : Possible IR counterpart
  87. GRB 030115: Radio Observations
  88. GRB030115 (=H2533): A Long GRB Localized by the HETE WXM and SXC
  89. Distribution of INTEGRAL SPI-ACS triggers for GRB bursts
  90. IPN triangulation of GRB030115B (annulus)
  91. ANNOUNCEMENT ON INTEGRAL GRB ALERTS
  92. Distribution of INTEGRAL SPI-ACS triggers
  93. GRB030115: R-band observations at Asiago
  94. GRB030115: TAROT optical observations
  95. GRB 021211: VLT spectrum
  96. GRB 030115: APO Optical Observations
  97. GRB 030115, no optical candidate
  98. GRB 030115, optical observations
  99. GRB 030115, optical candidate
  100. Possible GRB030113 seen by SPI ACS

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