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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"

24606 results found.

  1. GRB010222, possible increase of optical decay slope
  2. GRB 010222 Kyoto optical observation
  3. GRB010222 R-BAND OBSERVATION
  4. GRB010214 follow-up from Hanle
  5. GRB 010222: Near-IR Observations
  6. GRB 010222: Optical Observations
  7. GRB010222: Optical decay slope
  8. GRB 010214, Optical Observations
  9. GRB010222, radio observations
  10. GRB010222, optical observations
  11. GRB010222: BeppoSAX/NFI Observations
  12. GRB010214B,Gamma Ray Observations
  13. GRB 010220, simultaneous optical observations
  14. GRB010220: BeppoSAX WFC and GRBM preliminary data
  15. GRB010214, candidate optical afterglow
  16. GRB010214, optical observations
  17. GRB010214: BeppoSAX WFC and GRBM preliminary data
  18. GRB 010214: X-Ray afterglow
  19. GRB 010214 optical observation
  20. GRB010213, Radio Observations
  21. J-Band Observation of GRB 010214.
  22. GRB010213, Near-IR observations
  23. Possible InfraRed Transient of GRB 010214.
  24. GRB 010214, optical observations
  25. GRB010213 detected by HETE
  26. IPN Status Report
  27. HETE Status
  28. IPN/RXTE TRIANGULATION OF GRB010126
  29. GRB010126 Optical Observations
  30. IPN TRIANGULATION OF GRB010126
  31. Optical Observations of GRB 001018 at Keck
  32. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  33. Optical observations of GRB 001018 with JCAM
  34. IPN TRIANGULATION OF GRB010115
  35. IPN TRIANGULATION OF GRB010109
  36. IPN TRIANGULATION OF GRB010109
  37. IPN triangulation of GRB010104
  38. IPN triangulation of GRB010103
  39. H band observation of GRB 001212
  40. IPN triangulation of GRB001219
  41. GRB 001212 Optical Observation
  42. GRB 001212 Optical Observation
  43. GRB 001212 possible OA in 2MASS
  44. IPN triangulation of GRB001212
  45. Confirmation of IPN position for GRB001204
  46. IPN triangulation of GRB001204 (short/hard)
  47. GRB001120, optical observations
  48. WSRT 4.8 GHz observations of GRB001109
  49. IPN triangulation of GRB001120
  50. GRB 001109: deep JHK upper limits
  51. GRB 001109 X-ray afterglow with BeppoSAX
  52. CORRECTION to XMM-Newton observation of GRB001025
  53. GRB001109, Radio observations
  54. GRB001105 BVRI field photometry correction
  55. GRB001105, BVRI field photometry
  56. IPN TRIANGULATION OF GRB001105
  57. GRB 001025B, Optical obervations
  58. GRB 991208: HST Imaging of the Host Galaxy
  59. GRB 001025B, I-band observations
  60. XMM-Newton observation of GRB001025
  61. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  62. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  63. GRB001007: Optical observations
  64. ASM Localization of GRB 001025
  65. GRB001007, Radio observations
  66. GRB 001018, Possible Radio Afterglow
  67. GRB001018, Gamma Ray Observations
  68. IPN TRIANGULATION OF GRB001019
  69. IPN TRIANGULATION OF GRB001018
  70. IPN TRIANGULATION OF GRB 001017
  71. V,R,I band observations of GRB000926
  72. HETE positions added to GCN
  73. GRB000926 - Amateur Optical Observations
  74. CONCAM null result on GRB001005
  75. IPN triangulation of GRB001005
  76. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  77. GRB000926 - Optical observations
  78. GRB000926 - Optical observations
  79. GRB 000926, Optical Decay
  80. GRB000911: VLT infrared observation
  81. GRB 000926, Optical Observations
  82. GRB000926 K'-band Observation
  83. J and K band observations of GRB 000926
  84. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  85. CONCAM crude optical limits before and after GRB000926
  86. GRB 000926: Preliminary R-band Lightcurve
  87. Spectroscopic Redshift of GRB 000926
  88. GRB 000926: Optical candidate
  89. Optical candidate for GRB000926
  90. GRB 000911, BVRI field photometry
  91. GRB000911, Radio and Optical observations
  92. GRB000911: Optical observations
  93. GRB000830, BVRI field photometry
  94. GRB000210, Optical observations
  95. "Snapshot" afterglow IDs and GRB 000830
  96. GRB000730, Gamma Ray Observations
  97. GRB000812, Radio observations
  98. GRB000801, Gamma Ray Observations
  99. GRB000801, VLT-Antu R-band observations
  100. GRB 991208 Host Galaxy Imaging

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