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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"

24599 results found.

  1. GRB 010214, Optical Observations
  2. GRB010222, radio observations
  3. GRB010222, optical observations
  4. GRB010222: BeppoSAX/NFI Observations
  5. GRB010214B,Gamma Ray Observations
  6. GRB 010220, simultaneous optical observations
  7. GRB010220: BeppoSAX WFC and GRBM preliminary data
  8. GRB010214, candidate optical afterglow
  9. GRB010214, optical observations
  10. GRB010214: BeppoSAX WFC and GRBM preliminary data
  11. GRB 010214: X-Ray afterglow
  12. GRB 010214 optical observation
  13. GRB010213, Radio Observations
  14. J-Band Observation of GRB 010214.
  15. GRB010213, Near-IR observations
  16. Possible InfraRed Transient of GRB 010214.
  17. GRB 010214, optical observations
  18. GRB010213 detected by HETE
  19. IPN Status Report
  20. HETE Status
  21. IPN/RXTE TRIANGULATION OF GRB010126
  22. GRB010126 Optical Observations
  23. IPN TRIANGULATION OF GRB010126
  24. Optical Observations of GRB 001018 at Keck
  25. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  26. Optical observations of GRB 001018 with JCAM
  27. IPN TRIANGULATION OF GRB010115
  28. IPN TRIANGULATION OF GRB010109
  29. IPN TRIANGULATION OF GRB010109
  30. IPN triangulation of GRB010104
  31. IPN triangulation of GRB010103
  32. H band observation of GRB 001212
  33. IPN triangulation of GRB001219
  34. GRB 001212 Optical Observation
  35. GRB 001212 Optical Observation
  36. GRB 001212 possible OA in 2MASS
  37. IPN triangulation of GRB001212
  38. Confirmation of IPN position for GRB001204
  39. IPN triangulation of GRB001204 (short/hard)
  40. GRB001120, optical observations
  41. WSRT 4.8 GHz observations of GRB001109
  42. IPN triangulation of GRB001120
  43. GRB 001109: deep JHK upper limits
  44. GRB 001109 X-ray afterglow with BeppoSAX
  45. CORRECTION to XMM-Newton observation of GRB001025
  46. GRB001109, Radio observations
  47. GRB001105 BVRI field photometry correction
  48. GRB001105, BVRI field photometry
  49. IPN TRIANGULATION OF GRB001105
  50. GRB 001025B, Optical obervations
  51. GRB 991208: HST Imaging of the Host Galaxy
  52. GRB 001025B, I-band observations
  53. XMM-Newton observation of GRB001025
  54. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  55. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  56. GRB001007: Optical observations
  57. ASM Localization of GRB 001025
  58. GRB001007, Radio observations
  59. GRB 001018, Possible Radio Afterglow
  60. GRB001018, Gamma Ray Observations
  61. IPN TRIANGULATION OF GRB001019
  62. IPN TRIANGULATION OF GRB001018
  63. IPN TRIANGULATION OF GRB 001017
  64. V,R,I band observations of GRB000926
  65. HETE positions added to GCN
  66. GRB000926 - Amateur Optical Observations
  67. CONCAM null result on GRB001005
  68. IPN triangulation of GRB001005
  69. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  70. GRB000926 - Optical observations
  71. GRB000926 - Optical observations
  72. GRB 000926, Optical Decay
  73. GRB000911: VLT infrared observation
  74. GRB 000926, Optical Observations
  75. GRB000926 K'-band Observation
  76. J and K band observations of GRB 000926
  77. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  78. CONCAM crude optical limits before and after GRB000926
  79. GRB 000926: Preliminary R-band Lightcurve
  80. Spectroscopic Redshift of GRB 000926
  81. GRB 000926: Optical candidate
  82. Optical candidate for GRB000926
  83. GRB 000911, BVRI field photometry
  84. GRB000911, Radio and Optical observations
  85. GRB000911: Optical observations
  86. GRB000830, BVRI field photometry
  87. GRB000210, Optical observations
  88. "Snapshot" afterglow IDs and GRB 000830
  89. GRB000730, Gamma Ray Observations
  90. GRB000812, Radio observations
  91. GRB000801, Gamma Ray Observations
  92. GRB000801, VLT-Antu R-band observations
  93. GRB 991208 Host Galaxy Imaging
  94. IPN localization of GRB000730B
  95. GRB 990510: Possible detection of a host galaxy
  96. GRB 990510 Host Galaxy Discovery
  97. IPN localization of GRB000727
  98. GRB 990712: Late time HST/STIS Observations
  99. GRB 991216, HST/STIS observations
  100. GRB000620, Radio Observations

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