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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"

17213 results found.

  1. GRB010222, CXO X-ray observations
  2. GRB010324: BeppoSAX/GRBM data
  3. GRB010324, optical observations
  4. GRB010326B: Localization by HETE (2nd GRB for this date)
  5. GRB 010326 optical observations
  6. GRB010326: Refined Localization by HETE
  7. GRB010326: Localization by HETE
  8. Optical Observations of GRB 010324
  9. IPN TRIANGULATION OF GRB010324
  10. GRB010222, late-time optical observation
  11. Support extension to the BeppoSAX mission
  12. GRB 010222, Optical Observations
  13. GRB010220 optical obsercations
  14. GRB010222 - Optical observation
  15. GRB010222 further R-band photometry
  16. GRB 010222: Keck Spectroscopy
  17. GRB010214, field photometry
  18. GRB010222, field photometry
  19. GRB010222 further R-band photometry
  20. GRB 010222 Kyoto optical observation
  21. GRB010222 R-BAND OBSERVATION
  22. GRB010214 follow-up from Hanle
  23. GRB 010222: Near-IR Observations
  24. GRB 010222: Optical Observations
  25. GRB 010222, Decay Slope Confirmed
  26. GRB010222, radio observations
  27. GRB010222, optical observations
  28. GRB 010220, simultaneous optical observations
  29. GRB010220: BeppoSAX WFC and GRBM preliminary data
  30. GRB010214, optical observations
  31. GRB010214: BeppoSAX WFC and GRBM preliminary data
  32. GRB 010214: X-Ray afterglow
  33. GRB 010214 optical observation
  34. J-Band Observation of GRB 010214.
  35. GRB010214, optical observations
  36. GRB010213, optical observations
  37. GRB010213, Near-IR observations
  38. Possible InfraRed Transient of GRB 010214.
  39. GRB010214 Optical Observation
  40. GRB010213 detected by HETE
  41. HETE Status
  42. Optical Observations of GRB 001018 at Keck
  43. Optical observations of GRB 001018 with JCAM
  44. IPN TRIANGULATION OF GRB010109
  45. IPN triangulation of GRB010104
  46. IPN triangulation of GRB010103
  47. IPN triangulation of GRB001219
  48. GRB 001212 Optical Observation
  49. GRB 001212 Optical Observation
  50. GRB001120, optical observations
  51. GRB 001109: deep JHK upper limits
  52. GRB 001109 X-ray afterglow with BeppoSAX
  53. CORRECTION to XMM-Newton observation of GRB001025
  54. GRB001109, Radio observations
  55. GRB001105 BVRI field photometry correction
  56. GRB001105, BVRI field photometry
  57. GRB 001025B, Optical obervations
  58. GRB 991208: HST Imaging of the Host Galaxy
  59. GRB 001025B, I-band observations
  60. GRB 001025A, optical observation
  61. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  62. GRB001007: Optical observations
  63. GRB001007, Radio observations
  64. IPN TRIANGULATION OF GRB001020
  65. CORRECTION TO PEAK FLUX OF GRB001018
  66. IPN TRIANGULATION OF GRB 001017
  67. V,R,I band observations of GRB000926
  68. GRB000926 - Amateur Optical Observations
  69. CONCAM null result on GRB001005
  70. GRB000926 - Optical observations
  71. GRB000926 - Optical observations
  72. GRB 000926, Optical Observations
  73. GRB000926 K'-band Observation
  74. J and K band observations of GRB 000926
  75. CONCAM crude optical limits before and after GRB000926
  76. GRB 000926: Optical candidate
  77. Optical candidate for GRB000926
  78. GRB 000911, BVRI field photometry
  79. GRB000911, Radio and Optical observations
  80. GRB000911: Optical observations
  81. False GRB alarm from RXTE/ASM on 8 Sept 2000
  82. GRB000830, BVRI field photometry
  83. GRB000830: Optical observations
  84. IPN localization of GRB000820
  85. IPN localization of GRB000812
  86. GRB000801, VLT-Antu R-band observations
  87. GRB 991208 Host Galaxy Imaging
  88. IPN localization of GRB000730B
  89. IPN localization of GRB000730B
  90. GRB 990510: Possible detection of a host galaxy
  91. GRB 990510 Host Galaxy Discovery
  92. GRB 990712: Late time HST/STIS Observations
  93. GRB 991216, HST/STIS observations
  94. GRB000630, optical observations
  95. GRB000630, Revised BVRI Field Photometry
  96. GRB000630, Optical Observations
  97. GRB000630, optical observations
  98. GRB000630, optical observations
  99. GRB000630, BVRI Field Photometry
  100. GRB000630, optical observations

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