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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

42636 results found.

  1. GRB021219, optical observation by MASTER
  2. GRB021219: Correction to GCN 1766
  3. GRB021219 refined position with INTEGRAL
  4. VLT spectra of GRB 021211 revisited
  5. GRB021219: a long GRB localized by INTEGRAL
  6. GRB021211: APO optical observations
  7. IPN detection of continued activity from SGR1806-20
  8. IPN triangulation of GRB021215 (large error box)
  9. IPN triangulation of GRB021214 (annulus)
  10. XRF 020903 : HST observations
  11. GRB 021201: Optical Observations
  12. GRB 021211, optical observations
  13. GRB 021211: CTIO observations
  14. GRB021211: Measurement of Early Time Afterglow
  15. VLT spectrum of GRB 021211
  16. IPN triangulation of GRB021211B (two large error boxes)
  17. GRB 021211: early break in light curve
  18. GRB021211, BVRI field photometry
  19. GRB 021211, IR observations
  20. GRB 021211, optical observations
  21. GRB 021211: Optical Observations
  22. GRB021211: Kiso Observations
  23. GRB 021201, optical observations
  24. GRB 021211: Radio Observations
  25. GRB 021201 (short/hard), NOT observations
  26. SUB-MM SEARCH FOR GRB 021211
  27. Chandra observation of the IPN error box of GRB021201 (short/hard)
  28. GRB 021211 Milagro GeV/TeV Observations
  29. GRB 021211, R- and I-band observations
  30. GRB021211 - Upper limits from recent and historical observations
  31. GRB021211, OT at 108 s
  32. GRB021211 (HETE2493), OT at 143 sec
  33. GRB 021204: I-band Observations
  34. GRB021211 (=H2493): A Bright, Long GRB Localized by HETE-2 in Near-Real Time
  35. HETE 2493: Optical observations
  36. HETE 2493: Optical candidate
  37. GRB 021204: Optical Observations at RIKEN
  38. GRB 021125: Radio Observations
  39. IPN triangulation of GRB021206 (small error box)
  40. IPN triangulation of GRB021206 (exceptionally bright; annulus only)
  41. IPN detection of renewed activity from SGR1806-20
  42. IPN triangulation of GRB021205 (large error box)
  43. GRB 021104, GRB 021112 and GRB 021113 - Milagro GeV/TeV Observations
  44. GRB021201, BVRcIc field photometry
  45. GRB 021201, Radio Observations
  46. GRB 021201: BOOTES simultaneous optical observations
  47. IPN triangulation of GRB021201 (short/hard burst, small error box)
  48. Radio Catalog of GRB Afterglows
  49. GRB021004, late time optical observations
  50. GRB021004 Chandra Observation
  51. IPN detection of continued SGR1900+14 activity
  52. GRB021125 refined position
  53. IPN triangulation of GRB021115 (annulus)
  54. IPN triangulation of GRB021125B (two large error boxes)
  55. IPN triangulation of GRB021119 (large error box)
  56. IPN triangulation of GRB021125B (annulus)
  57. Improved IPN error box for GRB021125
  58. IPN BURST POSITION
  59. IPN triangulation of GRB021125 (INTEGRAL BURST)
  60. GRB021125 : A long GRB localized by INTEGRAL
  61. IPN confirmation of the reactivation of SGR1900+14
  62. GRB021113, SPI ACS observation
  63. IPN triangulation of GRB021119 (annulus)
  64. GRB 021112: Afterglow or Variable Star?
  65. GRB 021113: Evidence for a Dark Optical Afterglow
  66. GRB 021112, Radio Observations
  67. GRB021112, BVRI field photometry
  68. GRB 021112: Variable Source in R-band search
  69. GRB021112: Optical Observations
  70. GRB021113: Kiso Observations
  71. IPN triangulation of GRB021109 (portion of annulus)
  72. IPN triangulation of GRB021113 (=H2449; annulus)
  73. IPN triangulation of GRB021108 (CORRECTION; TWO LARGE ERROR BOXES)
  74. GRB 021113: Optical observations
  75. GRB 021112: RAPTOR Observations
  76. GRB 021113: Optical Observations
  77. GRB021113 (=H2449): A Long GRB Localized by HETE
  78. GRB 021112: R-band search
  79. IPN triangulation of GRB021108 (large error box)
  80. GRB021112 (=H2448): A Long GRB Localized by HETE
  81. IPN triangulation of GRB021109 (annulus)
  82. IPN triangulation of GRB021108 (annulus)
  83. GRB021004: Near infrared spectroscopy
  84. GRB021104: Optical Observations
  85. IPN triangulation of GRB021104 (annulus)
  86. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  87. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  88. SGR1900+14 activity, November 2-4, 2002
  89. GRB021104: optical observations
  90. GRB021104: Candidate present in DSS
  91. GRB021104: possible optical afterglow
  92. IPN triangulation of GRB021102 (annulus)
  93. Detection of activity from SGR 1900+14 with the RXTE/PCA
  94. IPN triangulation of a burst from SGR1900+14 on November 01, 2002
  95. IPN triangulation of a burst from SGR1900+14 on October 29 2002
  96. IPN triangulation of GRB021025 (portion of annulus)
  97. IPN triangulation of GRB021027 (single large error box)
  98. GRB021004, late-time optical observations
  99. IPN triangulation of GRB021027 (two large error boxes)
  100. IPN triangulation of GRB021027 (annulus)

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