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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"

4252 results found.

  1. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  2. SGR1900+14 activity, November 2-4, 2002
  3. Detection of activity from SGR 1900+14 with the RXTE/PCA
  4. IPN triangulation of a burst from SGR1900+14 on November 01, 2002
  5. IPN triangulation of a burst from SGR1900+14 on October 29 2002
  6. IPN triangulation of GRB021020 (smaller error box)
  7. IPN triangulation of GRB021020
  8. GRB021016(=H2397): A Long GRB Localized by HETE
  9. IPN triangulation of GRB021013 (two small error boxes)
  10. GRB021004: BVRc photometry
  11. GRB 021004: Optical Observations
  12. IPN triangulation of GRB020914
  13. IPN detection of a burst from SGR1900+14
  14. IPN triangulation of GRB020715 (=GRB150702)
  15. IPN triangulation of GRB150702
  16. IPN triangulation of GRB020708
  17. IPN triangulation of GRB020708
  18. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  19. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  20. AXP 1E2259+586: quasi-simultaneous optical observation
  21. AXP 1E2259+586 optical observations
  22. SGR-like Bursts from the AXP 1E 2259+586
  23. GRB 020604, optical observations
  24. GRB020604, optical observations
  25. IPN triangulation of GRB020604
  26. GRB020531: Optical observations
  27. GRB020525, optical observations
  28. IPN detection of possible bursts from SGR1806-20
  29. IPN triangulation of GRB020525
  30. XRF 020427: Sudden Ionospheric Disturbance (SID)
  31. Mars Odyssey joins the IPN
  32. Short RXTE/ASM transient 020406; may be a GRB
  33. XRF/GRB 011030: Detection of the Probable Host Galaxy
  34. IPN detection and localization of Cygnus X-1 flares
  35. RXTE Observations of SGR 1900+14
  36. SGR1900+14 activity
  37. IPN/HETE Detection of Bursts from SGR1900+14
  38. IPN Upper Limits to a GRB Associated With SN2002ap
  39. IPN detection of further activity from SGR1806-20
  40. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  41. GRB010923 as seen by BeppoSAX GRBM
  42. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  43. Probable SGR or Short Duration GRB Detected by HETE
  44. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  45. GRB 010629 Optical Observations
  46. GRB010629: A Burst Localized by HETE
  47. Possible burst from SGR1806-20
  48. IPN detection of SGR1900+14
  49. X-ray precursors to the large flare from SGR 1900+14
  50. SGR 1900+14: No evidence of extended X-ray emission
  51. SGR 1900+14 : RXTE observations
  52. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  53. SGR1900+14
  54. SGR 1900+14: Correction to GCN 1049
  55. Millimeter observation of SGR 1900+14
  56. SGR 1900+14: Detection of extended X-ray emission
  57. Chandra Observations of SGR 1900+14
  58. SGR 1900+14, Chandra observations
  59. Chandra Observations of SGR 1900+14
  60. SGR1900+14, I-band observations
  61. GRB 980326: Late-time HST/STIS observations
  62. GRB 010214, I-band data
  63. GRB010214 Optical Observation
  64. GRB010126 optical observations
  65. Optical Observations of GRB 001018 at Keck
  66. IPN triangulation of GRB001219
  67. GRB 001109: deep JHK upper limits
  68. IPN TRIANGULATION OF GRB001105
  69. IPN TRIANGULATION OF GRB001020
  70. GRB 000926 Chandra Observation
  71. GRB000926 K'-band Observation
  72. HST/STIS observations of the host galaxy of GRB 980329
  73. SGR 1806-20 burst activity
  74. IPN localization of GRB000730B
  75. IPN localization of GRB000730B
  76. GRB 990510: Possible detection of a host galaxy
  77. GRB 990510 Host Galaxy Discovery
  78. GRB 990712: Late time HST/STIS Observations
  79. GRB 000630: Detection of the Optical Afterglow
  80. GRB000616 [IPN Position]
  81. GRB 000418: Detection of the Host Galaxy
  82. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  83. GRB000529: BeppoSAX WFC position
  84. GRB000528: BeppoSAX GRBM observations
  85. GRB000419 [IPN Position]
  86. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  87. GRB 000326: Optical Observations
  88. GRB 000301C, Optical Observation
  89. GRB000301C
  90. GRB 000301C : Optical Candidate
  91. GRB000226 [IPN Position]
  92. HST Observations of GRB 990712
  93. IPN annulus for GRB000214
  94. GRB000126, optical observations
  95. IPN localization of GRB000126
  96. GRB991216 late optical observation
  97. BEPPOSAX GRBM Localization of GRB991226
  98. IPN error boxes for GRB991229
  99. IPN localization of GRB991226
  100. IPN localization of GRB991208

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