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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"

36143 results found.

  1. GRB010213 (HETE) TAROT observations
  2. GRB 010214, optical observations
  3. BeppoSAX ALERT: GRB010214
  4. IPN Status Report
  5. HETE Status
  6. GRB010126 opt. obs.
  7. IPN/RXTE TRIANGULATION OF GRB010126
  8. GRB010126: CONCAM crude optical limits during GRB
  9. GRB010126, TNG R-band observations
  10. IPN TRIANGULATION OF GRB010126
  11. IPN/RXTE TRIANGULATION OF GRB010126
  12. GRB 010119, optical observations
  13. GRB010119: Optical observations
  14. Optical Observations of GRB 001018 at Keck
  15. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  16. Optical observations of GRB 001018 with JCAM
  17. IPN TRIANGULATION OF GRB010115
  18. IPN TRIANGULATION OF GRB010109
  19. GRB010103, optical observations
  20. IPN triangulation of GRB010104
  21. IPN triangulation of GRB010103
  22. GRB 001204: Ks observations
  23. H band observation of GRB 001212
  24. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  25. IPN triangulation of GRB001219
  26. GRB 001212 Optical Observation
  27. GRB 001212 Optical Observation
  28. GRB 001212 optical observation
  29. GRB 001212 possible OA in 2MASS
  30. GRB 001212 possible OA
  31. IPN triangulation of GRB001212
  32. Confirmation of IPN position for GRB001204
  33. IPN triangulation of GRB001204 (short/hard)
  34. GRB 001105, further optical observations
  35. GRB001120: Gunn-i observations
  36. GRB001120: Optical observations
  37. GRB001109, optical observations
  38. GRB001120, optical observations
  39. IPN triangulation of GRB001120
  40. Optical/NIR observations of GRB001109
  41. GRB 001109: deep JHK upper limits
  42. GRB 001109 X-ray afterglow with BeppoSAX
  43. GRB001109: Optical observations
  44. GRB001109: BeppoSAX/NFI Observations
  45. GRB001109, R-band optical observations
  46. GRB001109, Radio observations
  47. BeppoSAX ALERT: GRB001109
  48. GRB001105 BVRI field photometry correction
  49. GRB001105, BVRI field photometry
  50. GRB 001105, R-band observation
  51. IPN TRIANGULATION OF GRB001105
  52. GRB 001025B, Optical obervations
  53. GRB 991208: HST Imaging of the Host Galaxy
  54. GRB000926: R-image of the host galaxy
  55. GRB 001025B, I-band observations
  56. GRB 001025 Optical Observations
  57. GRB 001025A, optical observation
  58. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  59. IPN triangulation of GRB001025
  60. ASM Localization of GRB 001025
  61. GRB001007, Radio observations
  62. IPN TRIANGULATION OF GRB001020
  63. GRB001019, Optical Observations
  64. GRB 001018, Possible Radio Afterglow
  65. GRB001018, Gamma Ray Observations
  66. IPN TRIANGULATION OF GRB001019
  67. IPN TRIANGULATION OF GRB001018
  68. IPN TRIANGULATION OF GRB 001017
  69. GRB 000926: Improved Absorber Redshift
  70. V,R,I band observations of GRB000926
  71. The Likely Optical/Infrared Afterglow of GRB 001011
  72. HETE positions added to GCN
  73. BeppoSAX ALERT: GRB001011
  74. GRB 001007, BVR-band observations
  75. GRB000926 - Amateur Optical Observations
  76. CONCAM null result on GRB001005
  77. IPN triangulation of GRB001007
  78. GRB 000926 : the host galaxy
  79. IPN triangulation of GRB001005
  80. GRB 000926 Chandra Observation
  81. IPN triangulation of GRB 001004
  82. Public availability of BeppoSAX data of GRB000926
  83. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  84. GRB 000926, Optical Decay
  85. GRB000926 - Optical observations
  86. GRB000926 - Optical observations
  87. GRB 000926: optical observations
  88. GRB 000926, Optical Observations
  89. GRB000926 K'-band Observation
  90. GRB000926 : increasing optical decay slope
  91. GRB000926 optical observations
  92. GRB000926 - Optical observations
  93. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  94. J and K band observations of GRB 000926
  95. GRB 000926: Lightcurve Update and Predictions
  96. GRB 000926, optical observation by Oksanen (vsnet-grb)
  97. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  98. CONCAM crude optical limits before and after GRB000926
  99. GRB 000926: Preliminary R-band Lightcurve
  100. GRB 000926 HST/Chandra TOO Status

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