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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"

37513 results found.

  1. REVISED LOCATION OF GRB010326A
  2. GRB 980326: Late-time HST/STIS observations
  3. GRB010324, field photometry
  4. GRB010326B, field photometry
  5. GRB010326, field photometry
  6. GRB010220, field photometry
  7. Further Optical Observations of GRB 010324
  8. GRB 010326A: Further optical observations
  9. GRB010324: BeppoSAX/GRBM data
  10. GRB 010326B: Optical observations
  11. GRB010324, optical observations
  12. GRB010326B: Localization by HETE (2nd GRB for this date)
  13. GRB 010326: Optical observations
  14. GRB 010326 optical observations
  15. GRB010326: Refined Localization by HETE
  16. GRB010326: Localization by HETE
  17. Duration, ECT, peak flux and fluence of GRB010324
  18. Optical Observations of GRB 010324
  19. IPN TRIANGULATION OF GRB010324
  20. GRB990705, VLT-FORS1 observations of the host galaxy
  21. GRB010222, late-time optical observation
  22. Support extension to the BeppoSAX mission
  23. GRB 010222 - HEGRA GeV/TeV Observations
  24. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  25. GRB010222: Chandra X-ray Observatory Observation
  26. GRB010222: Sub-millimeter vanishing act
  27. GRB 010222, Optical Observations
  28. GRB 010222: High-Resolution Keck Spectroscopy
  29. GRB 010214, I-band data
  30. Sub-millimeter Excess/GRB 010222
  31. GRB 010222
  32. GRB 010222 HST/Chandra TOO
  33. GRB 010222
  34. GRB010222 further R-band photometry
  35. GRB010222: R-band data
  36. GRB010222 Optical observations
  37. GRB 010222: Keck Spectroscopy
  38. GRB010214, field photometry
  39. GRB010222, field photometry
  40. GRB010222 further R-band photometry
  41. GRB010222, possible increase of optical decay slope
  42. GRB 010222 Kyoto optical observation
  43. GRB010222: fading behavior
  44. GRB 010222 BV optical observations
  45. GRB 010220: Near-IR Observations
  46. GRB010214 follow-up from Hanle
  47. GRB 010222: Near-IR Observations
  48. GRB 010222: Optical Observations
  49. GRB 010222, Decay Slope Confirmed
  50. GRB010222: Another absorption line system
  51. GRB010222: Optical decay slope
  52. GRB 010214, Optical Observations
  53. GRB010222: Sub-millimeter detection
  54. GRB010222: R-band fading behavior
  55. GRB010222: Optical Observations
  56. GRB010222, optical observations
  57. GRB010222: BeppoSAX/NFI Observations
  58. Redshift of the Optical Transient of GRB010222
  59. GRB010214B,Gamma Ray Observations
  60. GRB010222
  61. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  62. GRB 010220, simultaneous optical observations
  63. GRB010220: BeppoSAX WFC and GRBM preliminary data
  64. BeppoSAX ALERT: GRB010220
  65. GRB010214: BeppoSAX WFC and GRBM preliminary data
  66. GRB 010214: X-Ray afterglow
  67. GRB 010214, Optical Observations
  68. GRB 010214 optical observation
  69. GRB010213 Optical Observation
  70. J-Band Observation of GRB 010214.
  71. GRB010213, Near-IR observations
  72. Possible InfraRed Transient of GRB 010214.
  73. GRB010214 Optical Observation
  74. GRB010214: BeppoSAX/NFI Observations
  75. GRB010213 (HETE) TAROT observations
  76. GRB 010214, optical observations
  77. BeppoSAX ALERT: GRB010214
  78. IPN Status Report
  79. HETE Status
  80. GRB010126 opt. obs.
  81. IPN/RXTE TRIANGULATION OF GRB010126
  82. GRB010126: CONCAM crude optical limits during GRB
  83. GRB010126, TNG R-band observations
  84. IPN TRIANGULATION OF GRB010126
  85. IPN/RXTE TRIANGULATION OF GRB010126
  86. GRB 010119, optical observations
  87. GRB010119: Optical observations
  88. Optical Observations of GRB 001018 at Keck
  89. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  90. Optical observations of GRB 001018 with JCAM
  91. IPN TRIANGULATION OF GRB010115
  92. IPN TRIANGULATION OF GRB010109
  93. GRB010103, optical observations
  94. IPN triangulation of GRB010104
  95. IPN triangulation of GRB010103
  96. GRB 001204: Ks observations
  97. H band observation of GRB 001212
  98. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  99. IPN triangulation of GRB001219
  100. GRB 001212 Optical Observation

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