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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"

24356 results found.

  1. HETE Trigger #1759 (GRB 010920?) optical observations
  2. GRB 010222: HST observations -- host galaxy and late-time decay
  3. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  4. SGR1900+14 burst seen by HETE: BeppoSAX data
  5. SGR1900+14: High Fluence Burst Localized by HETE
  6. GRB010629: A Burst Localized by HETE
  7. SGR1900+14: Second Burst Localized by HETE
  8. SGR1900+14: A Burst Localized by HETE
  9. Possible burst from SGR1806-20
  10. IPN detection of SGR1900+14
  11. SGR1806-20: A Second, Intense Burst Localized by HETE
  12. SGR1806-20: Localization by HETE
  13. HETE Fully-Automated GCN Notices
  14. GRB000301C: Late-time HST/STIS observation
  15. GRB010518: a faint BeppoSAX detection
  16. GRB000418: HST/STIS Second-epoch Observations
  17. X-ray precursors to the large flare from SGR 1900+14
  18. GRB010427, Gamma Ray Observations
  19. SGR 1900+14 : RXTE observations
  20. Chandra Observations of SGR 1900+14
  21. Possible precursor to the SGR1900+14 giant burst
  22. SGR1900+14, I-band observations
  23. IPN Triangulation of the Giant Flare from SGR1900+14
  24. Giant flare from SGR1900+14
  25. GRB010412: BeppoSAX GRBM and WFC observations
  26. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002
  27. REVISED LOCATION OF GRB010326A
  28. GRB 980326: Late-time HST/STIS observations
  29. GRB010324, field photometry
  30. GRB010326B, field photometry
  31. GRB010326, field photometry
  32. Further Optical Observations of GRB 010324
  33. GRB010324: BeppoSAX/GRBM data
  34. GRB010324, optical observations
  35. GRB010326B: Localization by HETE (2nd GRB for this date)
  36. GRB010326: Refined Localization by HETE
  37. GRB010326: Localization by HETE
  38. Duration, ECT, peak flux and fluence of GRB010324
  39. GRB010222, late-time optical observation
  40. Support extension to the BeppoSAX mission
  41. GRB010222: Sub-millimeter vanishing act
  42. Sub-millimeter Excess/GRB 010222
  43. GRB 010222
  44. GRB010222 further R-band photometry
  45. GRB 010222: Keck Spectroscopy
  46. GRB010222 further R-band photometry
  47. GRB010222, possible increase of optical decay slope
  48. GRB010220, Optical Observations
  49. GRB010222 R-BAND OBSERVATION
  50. GRB 010222: Near-IR Observations
  51. GRB010222, optical observations
  52. Redshift of the Optical Transient of GRB010222
  53. GRB010214B,Gamma Ray Observations
  54. GRB 010220, simultaneous optical observations
  55. GRB010220: BeppoSAX WFC and GRBM preliminary data
  56. GRB010214: BeppoSAX WFC and GRBM preliminary data
  57. GRB 010214: X-Ray afterglow
  58. J-Band Observation of GRB 010214.
  59. GRB010214, optical observations
  60. GRB010213, optical observations
  61. Possible InfraRed Transient of GRB 010214.
  62. GRB010214 Optical Observation
  63. GRB010213 detected by HETE
  64. IPN Status Report
  65. HETE Status
  66. GRB010126 opt. obs.
  67. GRB010126: CONCAM crude optical limits during GRB
  68. GRB010126, TNG R-band observations
  69. GRB010126 optical observations
  70. GRB010126: Optical observations
  71. IPN/RXTE TRIANGULATION OF GRB010126
  72. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  73. GRB 001212 Optical Observation
  74. GRB 001212 Optical Observation
  75. GRB 001212 optical observation
  76. GRB 001212 possible OA
  77. Confirmation of IPN position for GRB001204
  78. GRB 001105, R-band observation
  79. GRB 001025B, Optical obervations
  80. GRB 991208: HST Imaging of the Host Galaxy
  81. ASM Localization of GRB 001025
  82. GRB001018, Gamma Ray Observations
  83. V,R,I band observations of GRB000926
  84. HETE positions added to GCN
  85. GRB000926 - Amateur Optical Observations
  86. CONCAM null result on GRB001005
  87. GRB 000926 : the host galaxy
  88. GRB 000926 Chandra Observation
  89. Public availability of BeppoSAX data of GRB000926
  90. GRB000926 - Optical observations
  91. GRB000926 - Optical observations
  92. GRB000911: VLT infrared observation
  93. GRB000911: optical VLT observations
  94. GRB000926 K'-band Observation
  95. J and K band observations of GRB 000926
  96. IPN triangulation of GRB000911
  97. False GRB alarm from RXTE/ASM on 8 Sept 2000
  98. GRB000830: Optical observations
  99. GRB000830, TNG B-band observations
  100. IPN localization of GRB000820

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