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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

32767 results found.

  1. GRB060218, optical observations
  2. GRB 060322: Confirmation of Swift XRT afterglow
  3. GRB 060211A: optical observation
  4. GRB060323: optical limit
  5. GRB060211B: optical observation
  6. SGR 1900+14: CORRECTION to GCN 4923
  7. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  8. GRB060323: NOT optical observations
  9. GRB 060322: Swift XRT afterglow candidate
  10. GRB060323: P60 Observations
  11. GRB 060323: Swift/UVOT Observations
  12. GRB 060323: optical afterglow confirmed
  13. GRB060323: NOT observations
  14. GRB 060323: Optical Observations
  15. GRB 060323: Tautenburg OT candidate retraction
  16. GRB 060323: Refined analysis of the Swift-BAT burst
  17. GRB 060323: optical observations at TNG
  18. GRB 060323: Swift XRT refined analysis
  19. GRB 060323: BVRI observations at Tautenburg, aftreglow candidate
  20. GRB 060323: Swift/XRT position
  21. GRB 060322: Refined analysis of the Swift-BAT burst
  22. GRB060323, optical observation
  23. GRB060206: optical observation
  24. GRB060218/SN2006aj: optical observations
  25. GRB 060218/SN 2006aj, LNA optical observation
  26. GRB060218: Refined photometric calibration of comparison stars
  27. GRB 060319: WHT K-band candidate afterglow
  28. GRB060319: Swift XRT refined analysis
  29. GRB060319: Swift/UVOT upper limits
  30. GRB 060319: Re-analysis of TNG data
  31. GRB060319: MASTER limit
  32. GRB 060319: Swift-BAT refined analysis
  33. GRB 060319 optical observations at TNG
  34. GRB060319 : Liverpool Telescope optical limit
  35. GRB060319 - SDSS Pre-burst Observations
  36. GRB060319: Swift/XRT position
  37. GRB060313: Radio Observations
  38. GRB 060313: early afterglow NIR upper limits with REM
  39. Konus-Wind observation of GRB 060313
  40. GRB060313: SSO 40inch Observations
  41. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  42. GRB 060313: PROMPT Observations
  43. GRB 060313: Swift/UVOT Observations
  44. GRB060313:Gemini South Observations
  45. GRB 060313: Swift-XRT team refined analysis
  46. GRB060313: optical observations of the afterglow candidate
  47. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  48. GRB 060313, SMARTS optical counterpart?
  49. GRB 060313: Possible optical counterpart
  50. GRB 060313: Swift XRT position
  51. GRB 060313, SMARTS optical/IR observations
  52. GRB060313: optical and near infrared observations with REM
  53. GRB060218: SARA Observations of SN2006aj
  54. GRB 060312: Refined analysis of the Swift-BAT burst
  55. GRB 060312: Swift XRT team refined analysis
  56. GRB060306: APO Ks-band Imaging Observations
  57. GRB 060312: ROTSE-III Optical Limits
  58. GRB 060306: SOAR Ks Observations
  59. GRB 060306: MAGNUM observations
  60. Swift/UVOT observations of GRB060306
  61. GRB 060306: Swift-BAT refined analysis
  62. GRB 060306: Swift-XRT team refined analysis
  63. GRB 060306: PROMPT Observations
  64. GRB 060218: RTT150 optical observations
  65. GRB060218: Ep,i - Eiso correlation
  66. GRB060223b: optical limit
  67. GRB060218/SN 2006aj: optical observation in V
  68. GRB060218/SN 2006aj: optical observation
  69. GRB 060121: HST observations
  70. GRB 060218 : GMRT observation [Correction and Improvement]
  71. GRB 060223b: Swift/UVOT Upper Limits
  72. GRB 060218/SN 2006aj, SMARTS optical/IR observations
  73. GRB 060223B: Swift XRT possible afterglow
  74. GRB 060218/SN 2006aj: ABT observations
  75. GRB 060218/SN 2006aj: REM optical and near-infrared observations
  76. GRB 060218 : Radio upper limits from GMRT
  77. GRB 060218/SN 2006aj: WIRO optical observations
  78. GRB 060218/SN 2006aj: RBO optical observations
  79. GRB 060204B: GETS early limit
  80. GRB 060218: Refined analysis of the radio afterglow
  81. GRB 060223B: ART optical limits
  82. GRB 060223B: Swift-BAT refined analysis
  83. GRB 060223a: Swift/UVOT refined analysis
  84. GRB 060223: Swift XRT Team preliminary analysis
  85. GRB 060218/SN 2006aj: Swift-BAT fluence and peak flux
  86. GRB 060223B: Swift detection of a bright burst
  87. GRB 060223: Swift-BAT refined analysis
  88. Correction to GCN 4816 on GRB060218
  89. GRB 060218/SN 2006aj: optical observations
  90. GRB060218: Optical brightening in V and R
  91. GRB 060223: Swift/UVOT Confirmation of Optical Afterglow
  92. Spectral properties of GRB060218/SN2006aj
  93. GRB 060219: Swift-BAT refined analysis
  94. GRB 060218: rebrightening
  95. GRB 060218: emergence of the underlying SN spectrum
  96. GRB 060218: Decline in r-band flux
  97. GRB 060218: spectroscopic observations
  98. GRB 060218: Further refined analysis of the Swift-BAT burst
  99. GRB 060218: Likely an underluminous GRB
  100. GRB060218: Optical Spectroscopy of GRB-SN

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