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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"

3870 results found.

  1. GRB 030227: Kyoto optical observation
  2. GRB030227: refined INTEGRAL position
  3. GRB 030131: marginal optical detection
  4. Probable GRB030112 seen by SPI ACS
  5. VLT spectroscopy of the probable host of GRB 021211
  6. IPN triangulation of GRB021219
  7. IPN detection of continued activity from SGR1806-20
  8. IPN triangulation of GRB021211B (two large error boxes)
  9. GRB021211 (=H2493): A Bright, Long GRB Localized by HETE-2 in Near-Real Time
  10. IPN detection of renewed activity from SGR1806-20
  11. GRB 021201: BOOTES simultaneous optical observations
  12. GRB021004, late time optical observations
  13. IPN detection of continued SGR1900+14 activity
  14. IPN confirmation of the reactivation of SGR1900+14
  15. IPN detection of possible reactivation of SGR1900+14
  16. GRB 021113: Evidence for a Dark Optical Afterglow
  17. GRB 021112: RAPTOR Observations
  18. GRB021112 (=H2448): A Long GRB Localized by HETE
  19. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  20. SGR1900+14 activity, November 2-4, 2002
  21. Detection of activity from SGR 1900+14 with the RXTE/PCA
  22. IPN triangulation of a burst from SGR1900+14 on November 01, 2002
  23. IPN triangulation of a burst from SGR1900+14 on October 29 2002
  24. IPN triangulation of GRB021020 (smaller error box)
  25. IPN triangulation of GRB021020
  26. GRB021016(=H2397): A Long GRB Localized by HETE
  27. IPN triangulation of GRB021013 (two small error boxes)
  28. GRB021004: BVRc photometry
  29. GRB 021004: Optical Observations
  30. IPN triangulation of GRB020914
  31. IPN detection of a burst from SGR1900+14
  32. IPN triangulation of GRB020715 (=GRB150702)
  33. IPN triangulation of GRB150702
  34. IPN triangulation of GRB020708
  35. IPN triangulation of GRB020708
  36. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  37. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  38. AXP 1E2259+586: quasi-simultaneous optical observation
  39. AXP 1E2259+586 optical observations
  40. SGR-like Bursts from the AXP 1E 2259+586
  41. GRB 020604, optical observations
  42. GRB020604, optical observations
  43. IPN triangulation of GRB020604
  44. GRB020531: Optical observations
  45. GRB020525, optical observations
  46. IPN detection of possible bursts from SGR1806-20
  47. IPN triangulation of GRB020525
  48. XRF 020427: Sudden Ionospheric Disturbance (SID)
  49. Mars Odyssey joins the IPN
  50. Short RXTE/ASM transient 020406; may be a GRB
  51. XRF/GRB 011030: Detection of the Probable Host Galaxy
  52. IPN detection and localization of Cygnus X-1 flares
  53. RXTE Observations of SGR 1900+14
  54. SGR1900+14 activity
  55. IPN/HETE Detection of Bursts from SGR1900+14
  56. IPN Upper Limits to a GRB Associated With SN2002ap
  57. IPN detection of further activity from SGR1806-20
  58. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  59. GRB010923 as seen by BeppoSAX GRBM
  60. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  61. Probable SGR or Short Duration GRB Detected by HETE
  62. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  63. GRB 010629 Optical Observations
  64. GRB010629: A Burst Localized by HETE
  65. Possible burst from SGR1806-20
  66. IPN detection of SGR1900+14
  67. X-ray precursors to the large flare from SGR 1900+14
  68. SGR 1900+14: No evidence of extended X-ray emission
  69. SGR 1900+14 : RXTE observations
  70. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  71. SGR1900+14
  72. SGR 1900+14: Correction to GCN 1049
  73. Millimeter observation of SGR 1900+14
  74. SGR 1900+14: Detection of extended X-ray emission
  75. Chandra Observations of SGR 1900+14
  76. SGR 1900+14, Chandra observations
  77. Chandra Observations of SGR 1900+14
  78. SGR1900+14, I-band observations
  79. GRB 980326: Late-time HST/STIS observations
  80. GRB 010214, I-band data
  81. GRB010214 Optical Observation
  82. GRB010126 optical observations
  83. Optical Observations of GRB 001018 at Keck
  84. IPN triangulation of GRB001219
  85. GRB 001109: deep JHK upper limits
  86. IPN TRIANGULATION OF GRB001105
  87. IPN TRIANGULATION OF GRB001020
  88. GRB 000926 Chandra Observation
  89. GRB000926 K'-band Observation
  90. HST/STIS observations of the host galaxy of GRB 980329
  91. SGR 1806-20 burst activity
  92. IPN localization of GRB000730B
  93. IPN localization of GRB000730B
  94. GRB 990510: Possible detection of a host galaxy
  95. GRB 990510 Host Galaxy Discovery
  96. GRB 990712: Late time HST/STIS Observations
  97. GRB 000630: Detection of the Optical Afterglow
  98. GRB000616 [IPN Position]
  99. GRB 000418: Detection of the Host Galaxy
  100. GRB000529: BeppoSAX NFI follow-up preliminary analysis

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