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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"

26681 results found.

  1. GRB 030226, optical observations
  2. GRB030226: Optical decay index
  3. GRB030226: Candidate optical afterglow
  4. GRB: Non-Referencing of GCN Circulars.
  5. IPN triangulation of GRB030217 (small error box)
  6. GRB 030131: marginal optical detection
  7. GRB 030204: Optical Observations
  8. GRB030204 field photometry
  9. GRB020819: Kiso R and I band observations
  10. GRB030131: Candidate Optical Afterglow
  11. GRB 030204, optical observations
  12. IPN triangulation of GRB030204 (small error box)
  13. GRB 030131, optical observations
  14. GRB 030131: afterglow candidate
  15. GRB 030115, late-time optical observations
  16. GRB 020819: Host galaxy at Radio Position
  17. GRB 020819: afterglow candidate
  18. GRB 030131 optical observations
  19. GRB 030131 optical observations
  20. A long GRB detected by INTEGRAL
  21. IPN triangulation of GRB030119 (two large error boxes)
  22. GRB 030115, simultaneous observations by BOOTES-1
  23. GRB 030115: IR observations with IRSF/SIRIUS
  24. IPN triangulation of GRB030115C (large error box)
  25. GRB030115, afterglow candidate
  26. GRB030115: Optical Observations, Swiss Telescope at La Silla (ESO, Chile)
  27. GRB 030115 : Possible IR counterpart
  28. GRB030115 (=H2533): A Long GRB Localized by the HETE WXM and SXC
  29. Distribution of INTEGRAL SPI-ACS triggers for GRB bursts
  30. GRB030115: R-band observations at Asiago
  31. GRB 030115: APO Optical Observations
  32. GRB 030115, no optical candidate
  33. GRB 030115, optical candidate
  34. IPN triangulation of GRB030102A (large error box)
  35. VLT spectroscopy of the probable host of GRB 021211
  36. GRB on 20030101 seen by SPI-ACS
  37. GRB 021211: Probable Host and Underlying Supernova
  38. GRB 021112: Evidence for Another Dark Optical Afterglow
  39. GRB 021219: OSN optical observations
  40. GRB021219, optical observations
  41. GRB021219, optical observation by MASTER
  42. GRB021219: a long GRB localized by INTEGRAL
  43. GRB021211: APO optical observations
  44. XRF 020903 : HST observations
  45. GRB 021201: Optical Observations
  46. GRB 021211: CTIO observations
  47. IPN triangulation of GRB021211B (two large error boxes)
  48. GRB021211, BVRI field photometry
  49. GRB021211: Optical observations in CrAO
  50. GRB 021211, optical observations
  51. GRB021211: Kiso Observations
  52. GRB 021201, optical observations
  53. GRB021211: Optical observations
  54. GRB 021201 (short/hard), NOT observations
  55. SUB-MM SEARCH FOR GRB 021211
  56. Chandra observation of the IPN error box of GRB021201 (short/hard)
  57. GRB 021211 Milagro GeV/TeV Observations
  58. GRB 021211, R- and I-band observations
  59. GRB021211 (=H2493): A Bright, Long GRB Localized by HETE-2 in Near-Real Time
  60. GRB 021125: Radio Observations
  61. IPN triangulation of GRB021206 (small error box)
  62. IPN triangulation of GRB021205 (large error box)
  63. GRB 021104, GRB 021112 and GRB 021113 - Milagro GeV/TeV Observations
  64. GRB021201, BVRcIc field photometry
  65. GRB 021201, Radio Observations
  66. GRB 021201: Optical Observations
  67. GRB 021201: BOOTES simultaneous optical observations
  68. IPN triangulation of GRB021201 (short/hard burst, small error box)
  69. GRB021004, late time optical observations
  70. GRB021004 Chandra Observation
  71. IPN detection of continued SGR1900+14 activity
  72. GRB021125 refined position
  73. Improved IPN error box for GRB021125
  74. IPN BURST POSITION
  75. IPN triangulation of GRB021125 (INTEGRAL BURST)
  76. GRB021125 : A long GRB localized by INTEGRAL
  77. IPN confirmation of the reactivation of SGR1900+14
  78. GRB 021112: Afterglow or Variable Star?
  79. GRB021113: optical observations at Bisei
  80. GRB021112, BVRI field photometry
  81. GRB 021112: Variable Source in R-band search
  82. GRB021112: Optical Observations
  83. GRB021113: Kiso Observations
  84. GRB 021113: Optical observations
  85. GRB 021112: RAPTOR Observations
  86. GRB 021113: Optical Observations
  87. GRB021113 (=H2449): A Long GRB Localized by HETE
  88. GRB 021112: R-band search
  89. GRB021112 (=H2448): A Long GRB Localized by HETE
  90. GRB 021016: Optical Observations
  91. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  92. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  93. SGR1900+14 activity, November 2-4, 2002
  94. GRB021104: Optical observations
  95. GRB021104: optical observations
  96. GRB021104: Candidate present in DSS
  97. Detection of activity from SGR 1900+14 with the RXTE/PCA
  98. IPN triangulation of GRB021027 (single large error box)
  99. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  100. GRB 021004: optical observations

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