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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"

45433 results found.

  1. GRB021211: Measurement of Early Time Afterglow
  2. VLT spectrum of GRB 021211
  3. IPN triangulation of GRB021211B (two large error boxes)
  4. GRB 021211: early break in light curve
  5. GRB021211, BVRI field photometry
  6. GRB021211: Optical observations in CrAO
  7. GRB 021211, IR observations
  8. GRB 021211, optical observations
  9. GRB 021211: Optical Observations
  10. GRB021211: Kiso Observations
  11. GRB021204: Kiso Observations
  12. GRB 021201, optical observations
  13. GRB 021211: Radio Observations
  14. GRB021211: Optical observations
  15. GRB 021201 (short/hard), NOT observations
  16. SUB-MM SEARCH FOR GRB 021211
  17. Chandra observation of the IPN error box of GRB021201 (short/hard)
  18. GRB 021211 Milagro GeV/TeV Observations
  19. GRB 021211, R- and I-band observations
  20. GRB021211 - Upper limits from recent and historical observations
  21. GRB021211, OT at 108 s
  22. GRB021211 (HETE2493), OT at 143 sec
  23. GRB 021204: I-band Observations
  24. GRB021211 (=H2493): A Bright, Long GRB Localized by HETE-2 in Near-Real Time
  25. HETE 2493: Optical observations
  26. HETE 2493: Optical candidate
  27. GRB 021204: Optical Observations at RIKEN
  28. GRB 021125: Radio Observations
  29. IPN triangulation of GRB021206 (small error box)
  30. IPN triangulation of GRB021206 (exceptionally bright; annulus only)
  31. IPN detection of renewed activity from SGR1806-20
  32. IPN triangulation of GRB021205 (large error box)
  33. GRB 021104, GRB 021112 and GRB 021113 - Milagro GeV/TeV Observations
  34. GRB021201, BVRcIc field photometry
  35. GRB 021201, Radio Observations
  36. GRB 021201: Optical Observations
  37. GRB 021201: BOOTES simultaneous optical observations
  38. IPN triangulation of GRB021201 (short/hard burst, small error box)
  39. Radio Catalog of GRB Afterglows
  40. GRB021004, late time optical observations
  41. GRB021004 Chandra Observation
  42. IPN detection of continued SGR1900+14 activity
  43. GRB021125 refined position
  44. IPN triangulation of GRB021115 (annulus)
  45. IPN triangulation of GRB021125B (two large error boxes)
  46. IPN triangulation of GRB021119 (large error box)
  47. IPN triangulation of GRB021125B (annulus)
  48. Improved IPN error box for GRB021125
  49. IPN triangulation of GRB021125 (INTEGRAL BURST)
  50. GRB021125 : A long GRB localized by INTEGRAL
  51. IPN confirmation of the reactivation of SGR1900+14
  52. IPN detection of possible reactivation of SGR1900+14
  53. GRB021113, SPI ACS observation
  54. IPN triangulation of GRB021119 (annulus)
  55. GRB 021112: Afterglow or Variable Star?
  56. GRB021113: optical observations at Bisei
  57. GRB 021113: Evidence for a Dark Optical Afterglow
  58. GRB 021112, Radio Observations
  59. GRB021112, BVRI field photometry
  60. GRB 021112: Variable Source in R-band search
  61. GRB021112: Optical Observations
  62. GRB021113: Kiso Observations
  63. IPN triangulation of GRB021109 (portion of annulus)
  64. IPN triangulation of GRB021113 (=H2449; annulus)
  65. IPN triangulation of GRB021108 (CORRECTION; TWO LARGE ERROR BOXES)
  66. GRB 021113: Optical observations
  67. GRB 021112: RAPTOR Observations
  68. GRB 021113: Optical Observations
  69. GRB021113 (=H2449): A Long GRB Localized by HETE
  70. GRB 021112: Optical Observations
  71. GRB 021112: R-band search
  72. IPN triangulation of GRB021108 (large error box)
  73. GRB021112 (=H2448): A Long GRB Localized by HETE
  74. GRB 021016: Optical Observations
  75. IPN triangulation of GRB021109 (annulus)
  76. IPN triangulation of GRB021108 (annulus)
  77. GRB021004: Near infrared spectroscopy
  78. GRB021104: Optical Observations
  79. IPN triangulation of GRB021104 (annulus)
  80. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  81. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  82. SGR1900+14 activity, November 2-4, 2002
  83. Spectropolarimetry of GRB021004
  84. GRB021104: Optical observations
  85. GRB021104: optical observations
  86. GRB021104: Candidate present in DSS
  87. GRB021104: possible optical afterglow
  88. IPN triangulation of GRB021102 (annulus)
  89. Detection of activity from SGR 1900+14 with the RXTE/PCA
  90. IPN triangulation of a burst from SGR1900+14 on November 01, 2002
  91. IPN triangulation of a burst from SGR1900+14 on October 29 2002
  92. IPN triangulation of GRB021025 (portion of annulus)
  93. IPN triangulation of GRB021027 (single large error box)
  94. GRB021004, late-time optical observations
  95. IPN triangulation of GRB021027 (two large error boxes)
  96. IPN triangulation of GRB021027 (annulus)
  97. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  98. IPN triangulation of GRB021025 (annulus)
  99. IPN triangulation of SGR1900+14, October 22 2002
  100. GRB 021004: optical observations

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