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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"

36129 results found.

  1. GRB 030228, optical observations
  2. GRB 030226: Steep Decline
  3. GRB 030227: Confirmed Optical Afterglow (S1-A)
  4. GRB 030226: R band polarimetric observations
  5. GRB 030226: Optical observations
  6. GRB 030227: fading of candidate optical afterglow 'S1-A'
  7. GRB030227:Optical observations
  8. GRB 20030226: Upper limits from recent and historical observations
  9. GRB 030227, possible optical counterpart of XMM-Newton source
  10. GRB030227 - faint tentative OT candidate
  11. GRB 030226, optical observations
  12. GRB030227: Kiso optical observations
  13. GRB 030227: Kyoto optical observation
  14. GRB 030226, optical light curve
  15. GRB 030226 spectroscopy
  16. Possible break in the GRB 030226 light curve
  17. GRB 030226 : Predicted light curve
  18. IPN triangulation of GRB030225 (annulus)
  19. GRB 030226: Confirmed decay index
  20. GRB030226: ESI spectroscopy
  21. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  22. GRB 030226 simultaneous optical observations
  23. Two absorption systems in GRB 030226
  24. GRB 030226, optical observations
  25. GRB 030226 Optical Spectra and R,I,z' Imaging
  26. GRB 030226, optical observations
  27. GRB 030226: Optical afterglow
  28. GRB 030217: Optical Observations at 4, 5, and 6 Days
  29. IPN triangulation of GRB030223 (annulus)
  30. IPN triangulation of GRB030220 (annulus)
  31. GRB: Non-Referencing of GCN Circulars.
  32. IPN triangulation of GRB030218 (annulus)
  33. IPN triangulation of GRB030217 (small error box)
  34. IPN triangulation of GRB030215C (annulus)
  35. IPN triangulation of GRB030217 (annulus)
  36. IPN triangulation of GRB030216 (annulus)
  37. IPN triangulation of GRB030215A and GRB030215B (annuli)
  38. GRB030115, WSRT radio observations - correction to GCN 1864
  39. GRB 030131: marginal optical detection
  40. GRB030115, WSRT radio observations
  41. IPN triangulation of GRB030206 (annulus)
  42. IPN triangulation of GRB030208 (annulus)
  43. GRB 030204: Optical Observations
  44. GRB030204 field photometry
  45. GRB020819: Kiso R and I band observations
  46. GRB 030204: Correction to GCN 1856
  47. GRB 030115: Optical Observations
  48. GRB 030204, optical observations
  49. IPN triangulation of GRB030204 (small error box)
  50. IPN triangulation of GRB030202 (annulus)
  51. GRB 030131, optical observations
  52. GRB030131: Kiso optical limit for corrected position
  53. GRB030131: Optical limits for corrected position
  54. GRB 030131: afterglow candidate
  55. GRB 030115, late-time optical observations
  56. GRB030131: corrected INTEGRAL position
  57. Type Ic SN2003L (SN/GRB?), optical spectrum
  58. GRB030131: Kiso Observations
  59. GRB 020819: Host galaxy at Radio Position
  60. IPN triangulation of GRB030131 - CORRECTION
  61. GRB 020819: afterglow candidate
  62. IPN triangulation of GRB030131
  63. GRB 030131 optical observations
  64. GRB 030131 optical observations
  65. A long GRB detected by INTEGRAL
  66. GRB030115: 1.2 mm upper limits with MAMBO @ IRAM 30m
  67. Type Ic SN2003L (SN/GRB?) Radio Observations
  68. IPN triangulation of GRB030127 (annulus)
  69. GRB030115 submm upper limit
  70. IPN triangulation of GRB030119 (two large error boxes)
  71. GRB 030115: Further IR observations with IRSF/SIRIUS
  72. IPN triangulation of GRB030117 (two large error boxes)
  73. Publicizing GRB Discoveries - A Message from NASA HQ
  74. GRB 030115: Radio detection of IR candidate
  75. GRB 030115, simultaneous observations by BOOTES-1
  76. GRB 030115: IR observations with IRSF/SIRIUS
  77. IPN triangulation of GRB030115C (large error box)
  78. GRB030115: R-band counterpart of IR candidate
  79. GRB030115, afterglow candidate
  80. GRB 021211: R-band observations at late-time
  81. GRB030115: Optical Observations, Swiss Telescope at La Silla (ESO, Chile)
  82. IPN triangulation of GRB030115B (small error box)
  83. GRB 030115 : Possible IR counterpart
  84. GRB 030115: Radio Observations
  85. GRB030115 (=H2533): A Long GRB Localized by the HETE WXM and SXC
  86. Distribution of INTEGRAL SPI-ACS triggers for GRB bursts
  87. IPN triangulation of GRB030115B (annulus)
  88. ANNOUNCEMENT ON INTEGRAL GRB ALERTS
  89. Distribution of INTEGRAL SPI-ACS triggers
  90. GRB030115: R-band observations at Asiago
  91. GRB030115: TAROT optical observations
  92. GRB 021211: VLT spectrum
  93. GRB 030115: APO Optical Observations
  94. GRB 030115, no optical candidate
  95. GRB 030115, optical observations
  96. GRB 030115, optical candidate
  97. Possible GRB030113 seen by SPI ACS
  98. Probable GRB030112B seen by SPI ACS
  99. Probable GRB030112 seen by SPI ACS
  100. Possible GRB030111 seen by SPI ACS

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