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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"

24705 results found.

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

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