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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').
Advanced Search

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"

4183 results found.

  1. GRB030328: Decay index
  2. GRB 030329: OT candidate
  3. GRB030328: optical spectroscopy at TNG
  4. GRB030328: optical photometry at the TNG
  5. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  6. IPN triangulation of GRB030326 (single small error box)
  7. GRB 030323: SARA Optical Observations
  8. IPN triangulation of GRB030325 (two small error boxes)
  9. GRB030323: V, R, I photometry
  10. GRB 030227: fading of candidate optical afterglow 'S1-A'
  11. GRB 030227, possible optical counterpart of XMM-Newton source
  12. GRB030227 - faint tentative OT candidate
  13. XMM-Newton observation of GRB030227
  14. GRB 030227: Kyoto optical observation
  15. GRB030227: refined INTEGRAL position
  16. GRB 030131: marginal optical detection
  17. Probable GRB030112 seen by SPI ACS
  18. VLT spectroscopy of the probable host of GRB 021211
  19. IPN triangulation of GRB021219
  20. IPN detection of continued activity from SGR1806-20
  21. IPN triangulation of GRB021211B (two large error boxes)
  22. GRB021211 (=H2493): A Bright, Long GRB Localized by HETE-2 in Near-Real Time
  23. IPN detection of renewed activity from SGR1806-20
  24. GRB 021201: BOOTES simultaneous optical observations
  25. GRB021004, late time optical observations
  26. IPN detection of continued SGR1900+14 activity
  27. IPN confirmation of the reactivation of SGR1900+14
  28. IPN detection of possible reactivation of SGR1900+14
  29. GRB 021113: Evidence for a Dark Optical Afterglow
  30. GRB 021112: RAPTOR Observations
  31. GRB021112 (=H2448): A Long GRB Localized by HETE
  32. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  33. SGR1900+14 activity, November 2-4, 2002
  34. Detection of activity from SGR 1900+14 with the RXTE/PCA
  35. IPN triangulation of a burst from SGR1900+14 on November 01, 2002
  36. IPN triangulation of a burst from SGR1900+14 on October 29 2002
  37. IPN triangulation of GRB021020 (smaller error box)
  38. IPN triangulation of GRB021020
  39. GRB021016(=H2397): A Long GRB Localized by HETE
  40. IPN triangulation of GRB021013 (two small error boxes)
  41. GRB021004: BVRc photometry
  42. GRB 021004: Optical Observations
  43. IPN triangulation of GRB020914
  44. IPN detection of a burst from SGR1900+14
  45. IPN triangulation of GRB020715 (=GRB150702)
  46. IPN triangulation of GRB150702
  47. IPN triangulation of GRB020708
  48. IPN triangulation of GRB020708
  49. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  50. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  51. AXP 1E2259+586: quasi-simultaneous optical observation
  52. AXP 1E2259+586 optical observations
  53. SGR-like Bursts from the AXP 1E 2259+586
  54. GRB 020604, optical observations
  55. GRB020604, optical observations
  56. IPN triangulation of GRB020604
  57. GRB020531: Optical observations
  58. GRB020525, optical observations
  59. IPN detection of possible bursts from SGR1806-20
  60. IPN triangulation of GRB020525
  61. XRF 020427: Sudden Ionospheric Disturbance (SID)
  62. Mars Odyssey joins the IPN
  63. Short RXTE/ASM transient 020406; may be a GRB
  64. XRF/GRB 011030: Detection of the Probable Host Galaxy
  65. IPN detection and localization of Cygnus X-1 flares
  66. RXTE Observations of SGR 1900+14
  67. SGR1900+14 activity
  68. IPN/HETE Detection of Bursts from SGR1900+14
  69. IPN Upper Limits to a GRB Associated With SN2002ap
  70. IPN detection of further activity from SGR1806-20
  71. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  72. GRB010923 as seen by BeppoSAX GRBM
  73. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  74. Probable SGR or Short Duration GRB Detected by HETE
  75. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  76. GRB 010629 Optical Observations
  77. GRB010629: A Burst Localized by HETE
  78. Possible burst from SGR1806-20
  79. IPN detection of SGR1900+14
  80. X-ray precursors to the large flare from SGR 1900+14
  81. SGR 1900+14: No evidence of extended X-ray emission
  82. SGR 1900+14 : RXTE observations
  83. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  84. SGR1900+14
  85. SGR 1900+14: Correction to GCN 1049
  86. Millimeter observation of SGR 1900+14
  87. SGR 1900+14: Detection of extended X-ray emission
  88. Chandra Observations of SGR 1900+14
  89. SGR 1900+14, Chandra observations
  90. Chandra Observations of SGR 1900+14
  91. SGR1900+14, I-band observations
  92. GRB 980326: Late-time HST/STIS observations
  93. GRB 010214, I-band data
  94. GRB010214 Optical Observation
  95. GRB010126 optical observations
  96. Optical Observations of GRB 001018 at Keck
  97. IPN triangulation of GRB001219
  98. GRB 001109: deep JHK upper limits
  99. IPN TRIANGULATION OF GRB001105
  100. IPN TRIANGULATION OF GRB001020

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