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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

36008 results found.

  1. GRB 030226 simultaneous optical observations
  2. Two absorption systems in GRB 030226
  3. GRB 030226, optical observations
  4. GRB 030226 Optical Spectra and R,I,z' Imaging
  5. GRB 030226, optical observations
  6. GRB 030226: Optical afterglow
  7. GRB 030217: Optical Observations at 4, 5, and 6 Days
  8. IPN triangulation of GRB030223 (annulus)
  9. IPN triangulation of GRB030220 (annulus)
  10. GRB: Non-Referencing of GCN Circulars.
  11. IPN triangulation of GRB030218 (annulus)
  12. IPN triangulation of GRB030217 (small error box)
  13. IPN triangulation of GRB030215C (annulus)
  14. IPN triangulation of GRB030217 (annulus)
  15. IPN triangulation of GRB030216 (annulus)
  16. IPN triangulation of GRB030215A and GRB030215B (annuli)
  17. GRB030115, WSRT radio observations - correction to GCN 1864
  18. GRB 030131: marginal optical detection
  19. GRB030115, WSRT radio observations
  20. IPN triangulation of GRB030206 (annulus)
  21. IPN triangulation of GRB030208 (annulus)
  22. GRB 030204: Optical Observations
  23. GRB030204 field photometry
  24. GRB020819: Kiso R and I band observations
  25. GRB 030204: Correction to GCN 1856
  26. GRB 030115: Optical Observations
  27. GRB 030204, optical observations
  28. IPN triangulation of GRB030204 (small error box)
  29. IPN triangulation of GRB030202 (annulus)
  30. GRB 030131, optical observations
  31. GRB030131: Kiso optical limit for corrected position
  32. GRB030131: Optical limits for corrected position
  33. GRB 030131: afterglow candidate
  34. GRB 030115, late-time optical observations
  35. GRB030131: corrected INTEGRAL position
  36. Type Ic SN2003L (SN/GRB?), optical spectrum
  37. GRB030131: Kiso Observations
  38. GRB 020819: Host galaxy at Radio Position
  39. IPN triangulation of GRB030131 - CORRECTION
  40. GRB 020819: afterglow candidate
  41. IPN triangulation of GRB030131
  42. GRB 030131 optical observations
  43. GRB 030131 optical observations
  44. A long GRB detected by INTEGRAL
  45. GRB030115: 1.2 mm upper limits with MAMBO @ IRAM 30m
  46. Type Ic SN2003L (SN/GRB?) Radio Observations
  47. IPN triangulation of GRB030127 (annulus)
  48. GRB030115 submm upper limit
  49. IPN triangulation of GRB030119 (two large error boxes)
  50. GRB 030115: Further IR observations with IRSF/SIRIUS
  51. IPN triangulation of GRB030117 (two large error boxes)
  52. Publicizing GRB Discoveries - A Message from NASA HQ
  53. GRB 030115: Radio detection of IR candidate
  54. GRB 030115, simultaneous observations by BOOTES-1
  55. GRB 030115: IR observations with IRSF/SIRIUS
  56. IPN triangulation of GRB030115C (large error box)
  57. GRB030115: R-band counterpart of IR candidate
  58. GRB030115, afterglow candidate
  59. GRB 021211: R-band observations at late-time
  60. GRB030115: Optical Observations, Swiss Telescope at La Silla (ESO, Chile)
  61. IPN triangulation of GRB030115B (small error box)
  62. GRB 030115 : Possible IR counterpart
  63. GRB 030115: Radio Observations
  64. GRB030115 (=H2533): A Long GRB Localized by the HETE WXM and SXC
  65. Distribution of INTEGRAL SPI-ACS triggers for GRB bursts
  66. IPN triangulation of GRB030115B (annulus)
  67. ANNOUNCEMENT ON INTEGRAL GRB ALERTS
  68. Distribution of INTEGRAL SPI-ACS triggers
  69. GRB030115: R-band observations at Asiago
  70. GRB030115: TAROT optical observations
  71. GRB 021211: VLT spectrum
  72. GRB 030115: APO Optical Observations
  73. GRB 030115, no optical candidate
  74. GRB 030115, optical observations
  75. GRB 030115, optical candidate
  76. Possible GRB030113 seen by SPI ACS
  77. Probable GRB030112B seen by SPI ACS
  78. Probable GRB030112 seen by SPI ACS
  79. Possible GRB030111 seen by SPI ACS
  80. Possible GRB030110b seen by SPI ACS
  81. Possible GRB 030110 seen by SPI ACS
  82. IPN triangulation of GRB030109 (annulus)
  83. IPN triangulation of GRB030105 (large error box)
  84. IPN triangulation of GRB030102B (refined localization - portion of annulus)
  85. Possible GRB 20030109 seen by SPI ACS
  86. IPN triangulation of GRB030102B (portion of annulus)
  87. IPN triangulation of GRB030102A (large error box)
  88. Possible GRB20030107 seen by SPI-ACS
  89. Possible GRB 20030105 seen by SPI ACS
  90. IPN triangulation of GRB030102 (annulus)
  91. GRB on 20030102 seen by SPI-ACS
  92. VLT spectroscopy of the probable host of GRB 021211
  93. GRB on 20030101 seen by SPI-ACS
  94. IPN triangulation of GRB030101 (two large error boxes)
  95. GRB021226
  96. GRB 021211: Probable Host and Underlying Supernova
  97. GRB 021226 registration by Helicon/Coronas-F
  98. Probable GRB in INTEGRAL SPI-ACS
  99. IPN triangulation of GRB021223 (two large error boxes)
  100. GRB021211, radio observations

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