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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"

24598 results found.

  1. GRB010222, radio observations
  2. GRB010222, optical observations
  3. GRB010222: BeppoSAX/NFI Observations
  4. GRB010214B,Gamma Ray Observations
  5. GRB 010220, simultaneous optical observations
  6. GRB010220: BeppoSAX WFC and GRBM preliminary data
  7. GRB010214, candidate optical afterglow
  8. GRB010214, optical observations
  9. GRB010214: BeppoSAX WFC and GRBM preliminary data
  10. GRB 010214: X-Ray afterglow
  11. GRB 010214 optical observation
  12. GRB010213, Radio Observations
  13. J-Band Observation of GRB 010214.
  14. GRB010213, Near-IR observations
  15. Possible InfraRed Transient of GRB 010214.
  16. GRB 010214, optical observations
  17. GRB010213 detected by HETE
  18. IPN Status Report
  19. HETE Status
  20. IPN/RXTE TRIANGULATION OF GRB010126
  21. GRB010126 Optical Observations
  22. IPN TRIANGULATION OF GRB010126
  23. Optical Observations of GRB 001018 at Keck
  24. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  25. Optical observations of GRB 001018 with JCAM
  26. IPN TRIANGULATION OF GRB010115
  27. IPN TRIANGULATION OF GRB010109
  28. IPN TRIANGULATION OF GRB010109
  29. IPN triangulation of GRB010104
  30. IPN triangulation of GRB010103
  31. H band observation of GRB 001212
  32. IPN triangulation of GRB001219
  33. GRB 001212 Optical Observation
  34. GRB 001212 Optical Observation
  35. GRB 001212 possible OA in 2MASS
  36. IPN triangulation of GRB001212
  37. Confirmation of IPN position for GRB001204
  38. IPN triangulation of GRB001204 (short/hard)
  39. GRB001120, optical observations
  40. WSRT 4.8 GHz observations of GRB001109
  41. IPN triangulation of GRB001120
  42. GRB 001109: deep JHK upper limits
  43. GRB 001109 X-ray afterglow with BeppoSAX
  44. CORRECTION to XMM-Newton observation of GRB001025
  45. GRB001109, Radio observations
  46. GRB001105 BVRI field photometry correction
  47. GRB001105, BVRI field photometry
  48. IPN TRIANGULATION OF GRB001105
  49. GRB 001025B, Optical obervations
  50. GRB 991208: HST Imaging of the Host Galaxy
  51. GRB 001025B, I-band observations
  52. XMM-Newton observation of GRB001025
  53. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  54. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  55. GRB001007: Optical observations
  56. ASM Localization of GRB 001025
  57. GRB001007, Radio observations
  58. GRB 001018, Possible Radio Afterglow
  59. GRB001018, Gamma Ray Observations
  60. IPN TRIANGULATION OF GRB001019
  61. IPN TRIANGULATION OF GRB001018
  62. IPN TRIANGULATION OF GRB 001017
  63. V,R,I band observations of GRB000926
  64. HETE positions added to GCN
  65. GRB000926 - Amateur Optical Observations
  66. CONCAM null result on GRB001005
  67. IPN triangulation of GRB001005
  68. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  69. GRB000926 - Optical observations
  70. GRB000926 - Optical observations
  71. GRB 000926, Optical Decay
  72. GRB000911: VLT infrared observation
  73. GRB 000926, Optical Observations
  74. GRB000926 K'-band Observation
  75. J and K band observations of GRB 000926
  76. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  77. CONCAM crude optical limits before and after GRB000926
  78. GRB 000926: Preliminary R-band Lightcurve
  79. Spectroscopic Redshift of GRB 000926
  80. GRB 000926: Optical candidate
  81. Optical candidate for GRB000926
  82. GRB 000911, BVRI field photometry
  83. GRB000911, Radio and Optical observations
  84. GRB000911: Optical observations
  85. GRB000830, BVRI field photometry
  86. GRB000210, Optical observations
  87. "Snapshot" afterglow IDs and GRB 000830
  88. GRB000730, Gamma Ray Observations
  89. GRB000812, Radio observations
  90. GRB000801, Gamma Ray Observations
  91. GRB000801, VLT-Antu R-band observations
  92. GRB 991208 Host Galaxy Imaging
  93. IPN localization of GRB000730B
  94. GRB 990510: Possible detection of a host galaxy
  95. GRB 990510 Host Galaxy Discovery
  96. IPN localization of GRB000727
  97. GRB 990712: Late time HST/STIS Observations
  98. GRB 991216, HST/STIS observations
  99. GRB000620, Radio Observations
  100. GRB000630, optical observations

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