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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"

37504 results found.

  1. GRB 010326B: Optical observations
  2. GRB010324, optical observations
  3. GRB010326B: Localization by HETE (2nd GRB for this date)
  4. GRB 010326: Optical observations
  5. GRB 010326 optical observations
  6. GRB010326: Refined Localization by HETE
  7. GRB010326: Localization by HETE
  8. Duration, ECT, peak flux and fluence of GRB010324
  9. Optical Observations of GRB 010324
  10. IPN TRIANGULATION OF GRB010324
  11. GRB990705, VLT-FORS1 observations of the host galaxy
  12. GRB010222, late-time optical observation
  13. Support extension to the BeppoSAX mission
  14. GRB 010222 - HEGRA GeV/TeV Observations
  15. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  16. GRB010222: Chandra X-ray Observatory Observation
  17. GRB010222: Sub-millimeter vanishing act
  18. GRB 010222, Optical Observations
  19. GRB 010222: High-Resolution Keck Spectroscopy
  20. GRB 010214, I-band data
  21. Sub-millimeter Excess/GRB 010222
  22. GRB 010222
  23. GRB 010222 HST/Chandra TOO
  24. GRB 010222
  25. GRB010222 further R-band photometry
  26. GRB010222: R-band data
  27. GRB010222 Optical observations
  28. GRB 010222: Keck Spectroscopy
  29. GRB010214, field photometry
  30. GRB010222, field photometry
  31. GRB010222 further R-band photometry
  32. GRB010222, possible increase of optical decay slope
  33. GRB 010222 Kyoto optical observation
  34. GRB010222: fading behavior
  35. GRB 010222 BV optical observations
  36. GRB 010220: Near-IR Observations
  37. GRB010214 follow-up from Hanle
  38. GRB 010222: Near-IR Observations
  39. GRB 010222: Optical Observations
  40. GRB 010222, Decay Slope Confirmed
  41. GRB010222: Another absorption line system
  42. GRB010222: Optical decay slope
  43. GRB 010214, Optical Observations
  44. GRB010222: Sub-millimeter detection
  45. GRB010222: R-band fading behavior
  46. GRB010222: Optical Observations
  47. GRB010222, optical observations
  48. GRB010222: BeppoSAX/NFI Observations
  49. Redshift of the Optical Transient of GRB010222
  50. GRB010214B,Gamma Ray Observations
  51. GRB010222
  52. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  53. GRB 010220, simultaneous optical observations
  54. GRB010220: BeppoSAX WFC and GRBM preliminary data
  55. BeppoSAX ALERT: GRB010220
  56. GRB010214: BeppoSAX WFC and GRBM preliminary data
  57. GRB 010214: X-Ray afterglow
  58. GRB 010214, Optical Observations
  59. GRB 010214 optical observation
  60. GRB010213 Optical Observation
  61. J-Band Observation of GRB 010214.
  62. GRB010213, Near-IR observations
  63. Possible InfraRed Transient of GRB 010214.
  64. GRB010214 Optical Observation
  65. GRB010214: BeppoSAX/NFI Observations
  66. GRB010213 (HETE) TAROT observations
  67. GRB 010214, optical observations
  68. BeppoSAX ALERT: GRB010214
  69. IPN Status Report
  70. HETE Status
  71. GRB010126 opt. obs.
  72. IPN/RXTE TRIANGULATION OF GRB010126
  73. GRB010126: CONCAM crude optical limits during GRB
  74. GRB010126, TNG R-band observations
  75. IPN TRIANGULATION OF GRB010126
  76. IPN/RXTE TRIANGULATION OF GRB010126
  77. GRB 010119, optical observations
  78. GRB010119: Optical observations
  79. Optical Observations of GRB 001018 at Keck
  80. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  81. Optical observations of GRB 001018 with JCAM
  82. IPN TRIANGULATION OF GRB010115
  83. IPN TRIANGULATION OF GRB010109
  84. GRB010103, optical observations
  85. IPN triangulation of GRB010104
  86. IPN triangulation of GRB010103
  87. GRB 001204: Ks observations
  88. H band observation of GRB 001212
  89. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  90. IPN triangulation of GRB001219
  91. GRB 001212 Optical Observation
  92. GRB 001212 Optical Observation
  93. GRB 001212 optical observation
  94. GRB 001212 possible OA in 2MASS
  95. GRB 001212 possible OA
  96. IPN triangulation of GRB001212
  97. Confirmation of IPN position for GRB001204
  98. IPN triangulation of GRB001204 (short/hard)
  99. GRB 001105, further optical observations
  100. GRB001120: Gunn-i observations

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