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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"

26352 results found.

  1. GRB 030320: Optical Observations
  2. IPN triangulation of GRB030320B (annulus)
  3. IPN triangulation of GRB030320 (small error box)
  4. Possible GRB 030320 localized by INTEGRAL
  5. GRB030226, addendum to GCN 1892
  6. IPN upper limit to a GRB associated with SN2003L
  7. IPN triangulation of GRB030317 (annulus)
  8. IPN triangulation of GRB030307 (annulus)
  9. GRB 030227: Optical limit at RIKEN
  10. IPN triangulation of GRB030306 (single small error box - REVISED)
  11. GRB030226: Optical observations at Asiago
  12. IPN triangulation of GRB030306 (intense; annulus only so far)
  13. GRB 030226: Optical observations
  14. GRB030226: Analysis of Chandra data
  15. IPN triangulation of GRB030304 (annulus)
  16. GRB 030227: Optical observations
  17. GRB030226, BVRc observations
  18. Chandra detection of the X-ray afterglow of GRB 030226
  19. GRB 030226, further optical/NIR imaging
  20. GRB030227: Kiso optical upper limit
  21. IPN triangulation of GRB030301 (annulus)
  22. IPN triangulation of GRB030228 (annulus)
  23. GRB030226, BVRcIc field calibration
  24. GRB 030227 optical afterglow
  25. GRB 030226: Steep Decline
  26. GRB 030227: Confirmed Optical Afterglow (S1-A)
  27. GRB 030226: Optical observations
  28. GRB 030227: fading of candidate optical afterglow 'S1-A'
  29. GRB 20030226: Upper limits from recent and historical observations
  30. GRB 030227, possible optical counterpart of XMM-Newton source
  31. GRB 030226, optical observations
  32. GRB030227: Kiso optical observations
  33. GRB 030226, optical light curve
  34. GRB030227 localized by INTEGRAL
  35. Possible break in the GRB 030226 light curve
  36. IPN triangulation of GRB030225 (annulus)
  37. GRB 030226: Confirmed decay index
  38. GRB030226: ESI spectroscopy
  39. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  40. GRB 030226: Optical afterglow
  41. GRB030226: Candidate optical afterglow
  42. IPN triangulation of GRB030223 (annulus)
  43. IPN triangulation of GRB030220 (annulus)
  44. GRB: Non-Referencing of GCN Circulars.
  45. IPN triangulation of GRB030218 (annulus)
  46. GRB030217: optical observations
  47. IPN triangulation of GRB030217 (small error box)
  48. IPN triangulation of GRB030215C (annulus)
  49. IPN triangulation of GRB030217 (annulus)
  50. IPN triangulation of GRB030216 (annulus)
  51. IPN triangulation of GRB030215A and GRB030215B (annuli)
  52. GRB 030131: marginal optical detection
  53. IPN triangulation of GRB030208 (annulus)
  54. GRB020819: Kiso R and I band observations
  55. GRB030131: Candidate Optical Afterglow
  56. IPN triangulation of GRB030204 (small error box)
  57. IPN triangulation of GRB030202 (annulus)
  58. GRB 030131, optical observations
  59. GRB030131: Optical limits for corrected position
  60. GRB 030115, late-time optical observations
  61. GRB030131: corrected INTEGRAL position
  62. GRB030131: Kiso Observations
  63. GRB 020819: Host galaxy at Radio Position
  64. IPN triangulation of GRB030131
  65. GRB030131: Optical limit
  66. GRB030131: refined position
  67. A long GRB detected by INTEGRAL
  68. IPN triangulation of GRB030127 (annulus)
  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 (=H2533): A Long GRB Localized by the HETE WXM and SXC
  78. IPN triangulation of GRB030115B (annulus)
  79. ANNOUNCEMENT ON INTEGRAL GRB ALERTS
  80. GRB030115: TAROT optical observations
  81. GRB 021211: VLT spectrum
  82. GRB 030115, optical observations
  83. GRB 030115, optical candidate
  84. Possible GRB030113 seen by SPI ACS
  85. Probable GRB030112B seen by SPI ACS
  86. Probable GRB030112 seen by SPI ACS
  87. Information about where HETE will be pointing
  88. Possible GRB030111 seen by SPI ACS
  89. Possible GRB030110b seen by SPI ACS
  90. Possible GRB 030110 seen by SPI ACS
  91. IPN triangulation of GRB030109 (annulus)
  92. IPN triangulation of GRB030105 (large error box)
  93. Possible GRB 20030109 seen by SPI ACS
  94. IPN triangulation of GRB030102B (portion of annulus)
  95. IPN triangulation of GRB030102A (large error box)
  96. Possible GRB20030107 seen by SPI-ACS
  97. Possible GRB 20030105 seen by SPI ACS
  98. IPN triangulation of GRB030102 (annulus)
  99. GRB on 20030102 seen by SPI-ACS
  100. VLT spectroscopy of the probable host of GRB 021211

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