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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"

43672 results found.

  1. GRB021211: APO optical observations
  2. IPN detection of continued activity from SGR1806-20
  3. IPN triangulation of GRB021215 (large error box)
  4. IPN triangulation of GRB021214 (annulus)
  5. XRF 020903 : HST observations
  6. GRB 021201: Optical Observations
  7. GRB 021211, optical observations
  8. GRB 021211: CTIO observations
  9. GRB021211: Measurement of Early Time Afterglow
  10. VLT spectrum of GRB 021211
  11. IPN triangulation of GRB021211B (two large error boxes)
  12. GRB 021211: early break in light curve
  13. GRB021211, BVRI field photometry
  14. GRB 021211, IR observations
  15. GRB 021211, optical observations
  16. GRB021211: Kiso Observations
  17. GRB 021201, optical observations
  18. GRB 021211: Radio Observations
  19. GRB021211: Optical observations
  20. GRB 021201 (short/hard), NOT observations
  21. SUB-MM SEARCH FOR GRB 021211
  22. Chandra observation of the IPN error box of GRB021201 (short/hard)
  23. GRB 021211 Milagro GeV/TeV Observations
  24. GRB 021211, R- and I-band observations
  25. GRB021211 - Upper limits from recent and historical observations
  26. GRB021211, OT at 108 s
  27. GRB021211 (HETE2493), OT at 143 sec
  28. GRB 021204: I-band Observations
  29. GRB021211 (=H2493): A Bright, Long GRB Localized by HETE-2 in Near-Real Time
  30. HETE 2493: Optical observations
  31. HETE 2493: Optical candidate
  32. GRB 021204: Optical Observations at RIKEN
  33. GRB 021125: Radio Observations
  34. IPN triangulation of GRB021206 (small error box)
  35. IPN triangulation of GRB021206 (exceptionally bright; annulus only)
  36. IPN detection of renewed activity from SGR1806-20
  37. IPN triangulation of GRB021205 (large error box)
  38. GRB 021104, GRB 021112 and GRB 021113 - Milagro GeV/TeV Observations
  39. GRB021201, BVRcIc field photometry
  40. GRB 021201, Radio Observations
  41. GRB 021201: BOOTES simultaneous optical observations
  42. IPN triangulation of GRB021201 (short/hard burst, small error box)
  43. Radio Catalog of GRB Afterglows
  44. GRB021004, late time optical observations
  45. GRB021004 Chandra Observation
  46. IPN detection of continued SGR1900+14 activity
  47. GRB021125 refined position
  48. IPN triangulation of GRB021115 (annulus)
  49. IPN triangulation of GRB021125B (two large error boxes)
  50. IPN triangulation of GRB021119 (large error box)
  51. IPN triangulation of GRB021125B (annulus)
  52. Improved IPN error box for GRB021125
  53. IPN BURST POSITION
  54. IPN triangulation of GRB021125 (INTEGRAL BURST)
  55. GRB021125 : A long GRB localized by INTEGRAL
  56. IPN confirmation of the reactivation of SGR1900+14
  57. IPN detection of possible reactivation of SGR1900+14
  58. GRB021113, SPI ACS observation
  59. IPN triangulation of GRB021119 (annulus)
  60. GRB 021112: Afterglow or Variable Star?
  61. GRB021113: optical observations at Bisei
  62. GRB 021113: Evidence for a Dark Optical Afterglow
  63. GRB 021112, Radio Observations
  64. GRB021112, BVRI field photometry
  65. GRB 021112: Variable Source in R-band search
  66. GRB021112: Optical Observations
  67. GRB021113: Kiso Observations
  68. IPN triangulation of GRB021109 (portion of annulus)
  69. IPN triangulation of GRB021113 (=H2449; annulus)
  70. IPN triangulation of GRB021108 (CORRECTION; TWO LARGE ERROR BOXES)
  71. GRB 021113: Optical observations
  72. GRB 021112: RAPTOR Observations
  73. GRB 021113: Optical Observations
  74. GRB021113 (=H2449): A Long GRB Localized by HETE
  75. GRB 021112: R-band search
  76. IPN triangulation of GRB021108 (large error box)
  77. GRB021112 (=H2448): A Long GRB Localized by HETE
  78. IPN triangulation of GRB021109 (annulus)
  79. IPN triangulation of GRB021108 (annulus)
  80. GRB021004: Near infrared spectroscopy
  81. GRB021104: Optical Observations
  82. IPN triangulation of GRB021104 (annulus)
  83. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  84. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  85. SGR1900+14 activity, November 2-4, 2002
  86. Spectropolarimetry of GRB021004
  87. GRB021104: Optical observations
  88. GRB021104: optical observations
  89. GRB021104: Candidate present in DSS
  90. GRB021104: possible optical afterglow
  91. IPN triangulation of GRB021102 (annulus)
  92. Detection of activity from SGR 1900+14 with the RXTE/PCA
  93. IPN triangulation of a burst from SGR1900+14 on November 01, 2002
  94. IPN triangulation of a burst from SGR1900+14 on October 29 2002
  95. IPN triangulation of GRB021025 (portion of annulus)
  96. IPN triangulation of GRB021027 (single large error box)
  97. GRB021004, late-time optical observations
  98. IPN triangulation of GRB021027 (two large error boxes)
  99. GRB 021023: Infrared Imaging
  100. IPN triangulation of GRB021027 (annulus)

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