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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"

39252 results found.

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