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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"

24595 results found.

  1. GRB010214B,Gamma Ray Observations
  2. GRB 010220, simultaneous optical observations
  3. GRB010220: BeppoSAX WFC and GRBM preliminary data
  4. GRB010214, candidate optical afterglow
  5. GRB010214, optical observations
  6. GRB010214: BeppoSAX WFC and GRBM preliminary data
  7. GRB 010214: X-Ray afterglow
  8. GRB 010214 optical observation
  9. GRB010213, Radio Observations
  10. J-Band Observation of GRB 010214.
  11. GRB010213, Near-IR observations
  12. Possible InfraRed Transient of GRB 010214.
  13. GRB 010214, optical observations
  14. GRB010213 detected by HETE
  15. IPN Status Report
  16. HETE Status
  17. IPN/RXTE TRIANGULATION OF GRB010126
  18. GRB010126 Optical Observations
  19. IPN TRIANGULATION OF GRB010126
  20. Optical Observations of GRB 001018 at Keck
  21. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  22. Optical observations of GRB 001018 with JCAM
  23. IPN TRIANGULATION OF GRB010115
  24. IPN TRIANGULATION OF GRB010109
  25. IPN TRIANGULATION OF GRB010109
  26. IPN triangulation of GRB010104
  27. IPN triangulation of GRB010103
  28. H band observation of GRB 001212
  29. IPN triangulation of GRB001219
  30. GRB 001212 Optical Observation
  31. GRB 001212 Optical Observation
  32. GRB 001212 possible OA in 2MASS
  33. IPN triangulation of GRB001212
  34. Confirmation of IPN position for GRB001204
  35. IPN triangulation of GRB001204 (short/hard)
  36. GRB001120, optical observations
  37. WSRT 4.8 GHz observations of GRB001109
  38. IPN triangulation of GRB001120
  39. GRB 001109: deep JHK upper limits
  40. GRB 001109 X-ray afterglow with BeppoSAX
  41. CORRECTION to XMM-Newton observation of GRB001025
  42. GRB001109, Radio observations
  43. GRB001105 BVRI field photometry correction
  44. GRB001105, BVRI field photometry
  45. IPN TRIANGULATION OF GRB001105
  46. GRB 001025B, Optical obervations
  47. GRB 991208: HST Imaging of the Host Galaxy
  48. GRB 001025B, I-band observations
  49. XMM-Newton observation of GRB001025
  50. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  51. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  52. GRB001007: Optical observations
  53. ASM Localization of GRB 001025
  54. GRB001007, Radio observations
  55. GRB 001018, Possible Radio Afterglow
  56. GRB001018, Gamma Ray Observations
  57. IPN TRIANGULATION OF GRB001019
  58. IPN TRIANGULATION OF GRB001018
  59. IPN TRIANGULATION OF GRB 001017
  60. V,R,I band observations of GRB000926
  61. HETE positions added to GCN
  62. GRB000926 - Amateur Optical Observations
  63. CONCAM null result on GRB001005
  64. IPN triangulation of GRB001005
  65. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  66. GRB000926 - Optical observations
  67. GRB000926 - Optical observations
  68. GRB 000926, Optical Decay
  69. GRB000911: VLT infrared observation
  70. GRB 000926, Optical Observations
  71. GRB000926 K'-band Observation
  72. J and K band observations of GRB 000926
  73. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  74. CONCAM crude optical limits before and after GRB000926
  75. GRB 000926: Preliminary R-band Lightcurve
  76. Spectroscopic Redshift of GRB 000926
  77. GRB 000926: Optical candidate
  78. Optical candidate for GRB000926
  79. GRB 000911, BVRI field photometry
  80. GRB000911, Radio and Optical observations
  81. GRB000911: Optical observations
  82. GRB000830, BVRI field photometry
  83. GRB000210, Optical observations
  84. "Snapshot" afterglow IDs and GRB 000830
  85. GRB000730, Gamma Ray Observations
  86. GRB000812, Radio observations
  87. GRB000801, Gamma Ray Observations
  88. GRB000801, VLT-Antu R-band observations
  89. GRB 991208 Host Galaxy Imaging
  90. IPN localization of GRB000730B
  91. GRB 990510: Possible detection of a host galaxy
  92. GRB 990510 Host Galaxy Discovery
  93. IPN localization of GRB000727
  94. GRB 990712: Late time HST/STIS Observations
  95. GRB 991216, HST/STIS observations
  96. GRB000620, Radio Observations
  97. GRB000630, optical observations
  98. GRB000630, Revised BVRI Field Photometry
  99. GRB000630, Optical Observations
  100. GRB000630, optical observations

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