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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"

17217 results found.

  1. IPN triangulation of GRB030102B (portion of annulus)
  2. VLT spectroscopy of the probable host of GRB 021211
  3. GRB 021211: Probable Host and Underlying Supernova
  4. GRB 021112: Evidence for Another Dark Optical Afterglow
  5. GRB 021219: OSN optical observations
  6. GRB021219, optical observations
  7. GRB021219, optical observation by MASTER
  8. GRB021219: a long GRB localized by INTEGRAL
  9. GRB021211: APO optical observations
  10. IPN triangulation of GRB021215 (large error box)
  11. XRF 020903 : HST observations
  12. GRB 021201: Optical Observations
  13. GRB 021211: CTIO observations
  14. GRB021211, BVRI field photometry
  15. GRB021211: Optical observations in CrAO
  16. GRB 021211, optical observations
  17. GRB021211: Kiso Observations
  18. GRB 021201, optical observations
  19. GRB021211: Optical observations
  20. GRB 021201 (short/hard), NOT observations
  21. Chandra observation of the IPN error box of GRB021201 (short/hard)
  22. GRB 021211, R- and I-band observations
  23. GRB021211 (=H2493): A Bright, Long GRB Localized by HETE-2 in Near-Real Time
  24. HETE 2493: Optical observations
  25. HETE 2493: Optical candidate
  26. GRB021201, BVRcIc field photometry
  27. GRB 021201: Optical Observations
  28. GRB 021201: BOOTES simultaneous optical observations
  29. IPN triangulation of GRB021201 (short/hard burst, small error box)
  30. GRB021004, late time optical observations
  31. IPN triangulation of GRB021119 (large error box)
  32. Improved IPN error box for GRB021125
  33. GRB021125 : A long GRB localized by INTEGRAL
  34. GRB 021112: Afterglow or Variable Star?
  35. GRB021113: optical observations at Bisei
  36. GRB021112, BVRI field photometry
  37. GRB 021112: Variable Source in R-band search
  38. GRB021112: Optical Observations
  39. GRB 021113: Optical observations
  40. GRB 021112: RAPTOR Observations
  41. GRB021113 (=H2449): A Long GRB Localized by HETE
  42. GRB021112 (=H2448): A Long GRB Localized by HETE
  43. GRB 021016: Optical Observations
  44. GRB021004: Near infrared spectroscopy
  45. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  46. SGR1900+14 activity, November 2-4, 2002
  47. GRB021104: optical observations
  48. Detection of activity from SGR 1900+14 with the RXTE/PCA
  49. IPN triangulation of GRB021027 (single large error box)
  50. GRB 021004: optical observations
  51. GRB021004: Optical Observations
  52. GRB021016(=H2397): A Long GRB Localized by HETE
  53. IPN triangulation of GRB021014 (large error box)
  54. IPN triangulation of GRB021013 (two small error boxes)
  55. XRF 020903: flattening of the optical light curve.
  56. GRB021004, UBVRcIc field photometry update
  57. IPN triangulation of GRB021008 (single error box)
  58. IPN triangulation of GRB021008 (two small error boxes)
  59. GRB021004 Chandra HETG Observations
  60. GRB 021004: Optical/NIR Observations
  61. GRB 021004: Additional V-band Polarimetric Observations
  62. GRB021004: optical observation
  63. GRB 021004: Host Galaxy Star Formation Rate
  64. GRB 021004: WC wind?
  65. GRB021004: NIR and Optical observations
  66. IPN triangulation of GRB021007 (annulus)
  67. XRF 020903 spectrum
  68. GRB021004: BVRc photometry
  69. GRB 021004 redshift
  70. GRB021004 radio observation
  71. HETE fluences for GRB021004
  72. GRB 021004: Optical Photometry at 2.5 Days
  73. GRB 021004: polarimetric observations
  74. GRB 021004: V-band Polarimetric Observations
  75. GRB021004: Update Bisei photometric data
  76. GRB 021004: Optical Decay
  77. GRB 021004 radio observation
  78. GRB 021004: Optical Photometry at 1.5 Days
  79. GRB021004, BVRcIc field photometry
  80. GRB021004: Optical Spectroscopy
  81. GRB 021004 radio search
  82. XRF020903, BVRI field photometry
  83. GRB021004(=H2380): A Long GRB Localized by HETE in Near-Real Time
  84. XRF020903: TNG and Asiago photometry
  85. XRF 020903: Correction to GCN 1560
  86. XRF 020903: VRI observations
  87. XRF 020903: R band observations
  88. IPN triangulation of GRB020923 (two error boxes)
  89. IPN triangulation of GRB020914 - clarification and additional information
  90. GRB 020305: HST/STIS observations
  91. XRF 020903: optical observation at Kyoto
  92. GRB020322 : HST/STIS observations
  93. XRF 020903: Optical observations
  94. IPN triangulation of GRB020904
  95. INTEGRAL GRBs added to GCN
  96. SGR1900+14 burst localized by HETE
  97. GRB020812: negative optical observations
  98. GRB 020812: optical observation at Kyoto University
  99. Second epoch K band imaging of GRB 020819
  100. GRB 020813 : HST observations

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