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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"

24601 results found.

  1. GRB 010222: Optical Observations
  2. GRB010222: Optical decay slope
  3. GRB 010214, Optical Observations
  4. GRB010222, radio observations
  5. GRB010222, optical observations
  6. GRB010222: BeppoSAX/NFI Observations
  7. GRB010214B,Gamma Ray Observations
  8. GRB 010220, simultaneous optical observations
  9. GRB010220: BeppoSAX WFC and GRBM preliminary data
  10. GRB010214, candidate optical afterglow
  11. GRB010214, optical observations
  12. GRB010214: BeppoSAX WFC and GRBM preliminary data
  13. GRB 010214: X-Ray afterglow
  14. GRB 010214 optical observation
  15. GRB010213, Radio Observations
  16. J-Band Observation of GRB 010214.
  17. GRB010213, Near-IR observations
  18. Possible InfraRed Transient of GRB 010214.
  19. GRB 010214, optical observations
  20. GRB010213 detected by HETE
  21. IPN Status Report
  22. HETE Status
  23. IPN/RXTE TRIANGULATION OF GRB010126
  24. GRB010126 Optical Observations
  25. IPN TRIANGULATION OF GRB010126
  26. Optical Observations of GRB 001018 at Keck
  27. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  28. Optical observations of GRB 001018 with JCAM
  29. IPN TRIANGULATION OF GRB010115
  30. IPN TRIANGULATION OF GRB010109
  31. IPN TRIANGULATION OF GRB010109
  32. IPN triangulation of GRB010104
  33. IPN triangulation of GRB010103
  34. H band observation of GRB 001212
  35. IPN triangulation of GRB001219
  36. GRB 001212 Optical Observation
  37. GRB 001212 Optical Observation
  38. GRB 001212 possible OA in 2MASS
  39. IPN triangulation of GRB001212
  40. Confirmation of IPN position for GRB001204
  41. IPN triangulation of GRB001204 (short/hard)
  42. GRB001120, optical observations
  43. WSRT 4.8 GHz observations of GRB001109
  44. IPN triangulation of GRB001120
  45. GRB 001109: deep JHK upper limits
  46. GRB 001109 X-ray afterglow with BeppoSAX
  47. CORRECTION to XMM-Newton observation of GRB001025
  48. GRB001109, Radio observations
  49. GRB001105 BVRI field photometry correction
  50. GRB001105, BVRI field photometry
  51. IPN TRIANGULATION OF GRB001105
  52. GRB 001025B, Optical obervations
  53. GRB 991208: HST Imaging of the Host Galaxy
  54. GRB 001025B, I-band observations
  55. XMM-Newton observation of GRB001025
  56. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  57. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  58. GRB001007: Optical observations
  59. ASM Localization of GRB 001025
  60. GRB001007, Radio observations
  61. GRB 001018, Possible Radio Afterglow
  62. GRB001018, Gamma Ray Observations
  63. IPN TRIANGULATION OF GRB001019
  64. IPN TRIANGULATION OF GRB001018
  65. IPN TRIANGULATION OF GRB 001017
  66. V,R,I band observations of GRB000926
  67. HETE positions added to GCN
  68. GRB000926 - Amateur Optical Observations
  69. CONCAM null result on GRB001005
  70. IPN triangulation of GRB001005
  71. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  72. GRB000926 - Optical observations
  73. GRB000926 - Optical observations
  74. GRB 000926, Optical Decay
  75. GRB000911: VLT infrared observation
  76. GRB 000926, Optical Observations
  77. GRB000926 K'-band Observation
  78. J and K band observations of GRB 000926
  79. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  80. CONCAM crude optical limits before and after GRB000926
  81. GRB 000926: Preliminary R-band Lightcurve
  82. Spectroscopic Redshift of GRB 000926
  83. GRB 000926: Optical candidate
  84. Optical candidate for GRB000926
  85. GRB 000911, BVRI field photometry
  86. GRB000911, Radio and Optical observations
  87. GRB000911: Optical observations
  88. GRB000830, BVRI field photometry
  89. GRB000210, Optical observations
  90. "Snapshot" afterglow IDs and GRB 000830
  91. GRB000730, Gamma Ray Observations
  92. GRB000812, Radio observations
  93. GRB000801, Gamma Ray Observations
  94. GRB000801, VLT-Antu R-band observations
  95. GRB 991208 Host Galaxy Imaging
  96. IPN localization of GRB000730B
  97. GRB 990510: Possible detection of a host galaxy
  98. GRB 990510 Host Galaxy Discovery
  99. IPN localization of GRB000727
  100. GRB 990712: Late time HST/STIS Observations

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