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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"

36141 results found.

  1. Chandra detection of the X-ray afterglow of GRB 030226
  2. GRB 030226, further optical/NIR imaging
  3. GRB030227, optical observations
  4. GRB 030226: Ic Observations
  5. GRB030227: Kiso optical upper limit
  6. IPN triangulation of GRB030301 (annulus)
  7. IPN triangulation of GRB030228 (annulus)
  8. GRB030227, BVRcIc field photometry
  9. GRB030226, BVRcIc field calibration
  10. GRB 030227 optical afterglow
  11. 030302: NOT A GRB
  12. 030228: NOT A GRB
  13. GRB 030228, optical observations
  14. GRB 030226: Steep Decline
  15. GRB 030227: Confirmed Optical Afterglow (S1-A)
  16. GRB 030226: R band polarimetric observations
  17. GRB 030226: Optical observations
  18. GRB 030227: fading of candidate optical afterglow 'S1-A'
  19. GRB030227:Optical observations
  20. GRB 20030226: Upper limits from recent and historical observations
  21. GRB 030227, possible optical counterpart of XMM-Newton source
  22. GRB030227 - faint tentative OT candidate
  23. GRB 030226, optical observations
  24. GRB030227: Kiso optical observations
  25. GRB 030227: Kyoto optical observation
  26. GRB 030226, optical light curve
  27. GRB 030226 spectroscopy
  28. Possible break in the GRB 030226 light curve
  29. GRB 030226 : Predicted light curve
  30. IPN triangulation of GRB030225 (annulus)
  31. GRB 030226: Confirmed decay index
  32. GRB030226: ESI spectroscopy
  33. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  34. GRB 030226 simultaneous optical observations
  35. Two absorption systems in GRB 030226
  36. GRB 030226, optical observations
  37. GRB 030226 Optical Spectra and R,I,z' Imaging
  38. GRB 030226, optical observations
  39. GRB 030226: Optical afterglow
  40. GRB 030217: Optical Observations at 4, 5, and 6 Days
  41. IPN triangulation of GRB030223 (annulus)
  42. IPN triangulation of GRB030220 (annulus)
  43. GRB: Non-Referencing of GCN Circulars.
  44. IPN triangulation of GRB030218 (annulus)
  45. IPN triangulation of GRB030217 (small error box)
  46. IPN triangulation of GRB030215C (annulus)
  47. IPN triangulation of GRB030217 (annulus)
  48. IPN triangulation of GRB030216 (annulus)
  49. IPN triangulation of GRB030215A and GRB030215B (annuli)
  50. GRB030115, WSRT radio observations - correction to GCN 1864
  51. GRB 030131: marginal optical detection
  52. GRB030115, WSRT radio observations
  53. IPN triangulation of GRB030206 (annulus)
  54. IPN triangulation of GRB030208 (annulus)
  55. GRB 030204: Optical Observations
  56. GRB030204 field photometry
  57. GRB020819: Kiso R and I band observations
  58. GRB 030204: Correction to GCN 1856
  59. GRB 030115: Optical Observations
  60. GRB 030204, optical observations
  61. IPN triangulation of GRB030204 (small error box)
  62. IPN triangulation of GRB030202 (annulus)
  63. GRB 030131, optical observations
  64. GRB030131: Kiso optical limit for corrected position
  65. GRB030131: Optical limits for corrected position
  66. GRB 030131: afterglow candidate
  67. GRB 030115, late-time optical observations
  68. GRB030131: corrected INTEGRAL position
  69. Type Ic SN2003L (SN/GRB?), optical spectrum
  70. GRB030131: Kiso Observations
  71. GRB 020819: Host galaxy at Radio Position
  72. IPN triangulation of GRB030131 - CORRECTION
  73. GRB 020819: afterglow candidate
  74. IPN triangulation of GRB030131
  75. GRB 030131 optical observations
  76. GRB 030131 optical observations
  77. A long GRB detected by INTEGRAL
  78. GRB030115: 1.2 mm upper limits with MAMBO @ IRAM 30m
  79. Type Ic SN2003L (SN/GRB?) Radio Observations
  80. IPN triangulation of GRB030127 (annulus)
  81. GRB030115 submm upper limit
  82. IPN triangulation of GRB030119 (two large error boxes)
  83. GRB 030115: Further IR observations with IRSF/SIRIUS
  84. IPN triangulation of GRB030117 (two large error boxes)
  85. Publicizing GRB Discoveries - A Message from NASA HQ
  86. GRB 030115: Radio detection of IR candidate
  87. GRB 030115, simultaneous observations by BOOTES-1
  88. GRB 030115: IR observations with IRSF/SIRIUS
  89. IPN triangulation of GRB030115C (large error box)
  90. GRB030115: R-band counterpart of IR candidate
  91. GRB030115, afterglow candidate
  92. GRB 021211: R-band observations at late-time
  93. GRB030115: Optical Observations, Swiss Telescope at La Silla (ESO, Chile)
  94. IPN triangulation of GRB030115B (small error box)
  95. GRB 030115 : Possible IR counterpart
  96. GRB 030115: Radio Observations
  97. GRB030115 (=H2533): A Long GRB Localized by the HETE WXM and SXC
  98. Distribution of INTEGRAL SPI-ACS triggers for GRB bursts
  99. IPN triangulation of GRB030115B (annulus)
  100. ANNOUNCEMENT ON INTEGRAL GRB ALERTS

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