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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"

4572 results found.

  1. IPN triangulation of GRB030208 (annulus)
  2. GRB 030131: afterglow candidate
  3. GRB 030115, simultaneous observations by BOOTES-1
  4. IPN triangulation of GRB030101 (two large error boxes)
  5. GRB 021211: Probable Host and Underlying Supernova
  6. IPN triangulation of GRB021219 - CORRECTION
  7. GRB 021211: CTIO observations
  8. GRB 021211: Optical Observations
  9. Chandra observation of the IPN error box of GRB021201 (short/hard)
  10. IPN detection of continued SGR1900+14 activity
  11. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  12. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  13. IPN triangulation of GRB021023 (small error boc)
  14. IPN triangulation of GRB021013 (single error box)
  15. IPN triangulation of GRB021013 (two small error boxes)
  16. GRB021004: NIR and Optical observations
  17. GRB021004: BVRc photometry
  18. GRB021004, Optical Observations
  19. GRB 021004: Optical Photometry at 1.5 Days
  20. GRB 021004, SPM optical observations
  21. GRB 021004: steepening of the optical decay slope
  22. GRB021004: Upper limits from recent and historical observations
  23. XRF 020903: Supernova
  24. IPN annulus for GRB020923
  25. GRB020903(=H2314): An X-Ray Flash Localized by HETE
  26. INTEGRAL GRBs added to GCN
  27. GRB 020812: early time optical observation at Ouda Station
  28. GRB020813: optical and NIR observations
  29. GRB 020813: addendum to GCN 1498
  30. GRB020812: NIR observations
  31. GRB020813, optical observations
  32. Further refinement to IPN error box for GRB020531
  33. GRB020625 (=H2081): A Long Burst Localized by HETE
  34. GRB020531: Second epoch Chandra observations
  35. GRB020531 Optical observations with TAROT
  36. GRB020531: Observations with the Chandra X-ray Observatory
  37. Refined IPN error box for GRB020531
  38. IPN triangulation of the short, hard GRB020531 (=H2042)
  39. GRB020321 : Optical observations.
  40. GRB 020124: Optical observations
  41. GRB 020409: Optical observations
  42. GRB 020409: No Evidence for an Optical Afterglow
  43. GRB 020331 Kyoto observation on March 31
  44. GRB 020409
  45. GRB020124 optical observations with RIBOTS/RIMOTS
  46. Short RXTE/ASM transient 020406; may be a GRB
  47. GRB 020321, Radio Observations
  48. GRB 020321: Optical observations
  49. GRB 020322 optical observations
  50. GRB020317 : Near IR Observations from Mt Abu Observatory
  51. GRB 020317 : KISO Optical Observations
  52. GRB 020317: Optical observations
  53. GRB011130 (XRF011130) Second Epoch Chandra Observations
  54. IPN detection and localization of Cygnus X-1 flares
  55. IPN Upper Limits to a GRB Associated With SN2002ap
  56. GRB020124: Optical observations
  57. GRB 020124: Optical observations
  58. GRB020124(=H1896): Localization of a Long GRB by HETE
  59. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  60. GRB 011121
  61. GRB011030, optical observation
  62. GRB010923 as seen by BeppoSAX GRBM
  63. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  64. GRB001109, Host Galaxy Astrometry
  65. GRB000926, Host Galaxy Observations
  66. GRB001109, Host Galaxy Spectroscopic Observations
  67. BeppoSAX/GRBM detection of GRB010728
  68. SGR1900+14: Second Burst Localized by HETE
  69. SGR1900+14: A Burst Localized by HETE
  70. Millimeter observation of SGR 1900+14
  71. GRB010324: BeppoSAX/GRBM data
  72. GRB 010214, I-band data
  73. Sub-millimeter Excess/GRB 010222
  74. GRB 010220: Near-IR Observations
  75. GRB 010222: Near-IR Observations
  76. GRB010214, optical observations
  77. J-Band Observation of GRB 010214.
  78. Possible InfraRed Transient of GRB 010214.
  79. GRB010214 Optical Observation
  80. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  81. IPN triangulation of GRB001219
  82. GRB 001212 Optical Observation
  83. GRB 001212 Optical Observation
  84. IPN triangulation of GRB001212
  85. GRB 001025B, I-band observations
  86. IPN TRIANGULATION OF GRB001020
  87. GRB 000926 : the host galaxy
  88. IPN triangulation of GRB001005
  89. J and K band observations of GRB 000926
  90. GRB000830, TNG B-band observations
  91. GRB000830: Optical observations
  92. Updated IPN coordinates for GRB000801
  93. IPN localization of GRB000801
  94. IPN localization of GRB000727
  95. GRB 990712: Late time HST/STIS Observations
  96. GRB000630: Optical observations
  97. GRB 000620: J-band observations
  98. GRB 000615: NIR further observations
  99. GRB 000615: NIR observations
  100. GRB000615: BeppoSAX GRB Alert

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