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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.

Advanced Search Examples (click to copy):

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

24993 results found.

  1. GRB 060322: Swift-BAT detection of a 200-sec burst
  2. GRB 060218/SN 2006aj, LNA optical observation
  3. GRB060218: Refined photometric calibration of comparison stars
  4. GRB 060319: WHT K-band candidate afterglow
  5. GRB060319: Swift/UVOT upper limits
  6. GRB 060319: Swift-BAT refined analysis
  7. GRB 060319 optical observations at TNG
  8. GRB060319 : Liverpool Telescope optical limit
  9. GRB060319 - SDSS Pre-burst Observations
  10. GRB060313: Radio Observations
  11. GRB 060313: early afterglow NIR upper limits with REM
  12. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  13. GRB 060313: Swift/UVOT Observations
  14. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  15. GRB 060313, SMARTS optical counterpart?
  16. GRB 060313, SMARTS optical/IR observations
  17. GRB060313: optical and near infrared observations with REM
  18. GRB060218: SARA Observations of SN2006aj
  19. GRB 060312: Refined analysis of the Swift-BAT burst
  20. GRB 060218/SN 2006aj, high resolution spectra
  21. GRB 060312: Swift XRT team refined analysis
  22. GRB060306: APO Ks-band Imaging Observations
  23. GRB 060312: ROTSE-III Optical Limits
  24. Bright short hard GRB 060303: IPN localization and Konus spectrum
  25. GRB060219: Liverpool Telescope observations
  26. GRB 060306: MAGNUM observations
  27. GRB060218: analysis of the XMM-Newton observation
  28. Swift/UVOT observations of GRB060306
  29. GRB 060306: Swift-BAT refined analysis
  30. GRB 060306: Swift-XRT team refined analysis
  31. GRB 060306: Swift detection of a bright burst
  32. GRB060218: Ep,i - Eiso correlation
  33. GRB060223b: optical limit
  34. GRB 060223b: Swift/UVOT Upper Limits
  35. GRB 060218/SN 2006aj: K-380 optical observations
  36. GRB 060218/SN 2006aj, SMARTS optical/IR observations
  37. GRB 060223B: Swift XRT possible afterglow
  38. GRB 060218/SN 2006aj: ABT observations
  39. GRB 060218/SN 2006aj: REM optical and near-infrared observations
  40. GRB 060218 : Radio upper limits from GMRT
  41. GRB 060218/SN 2006aj: RBO optical observations
  42. GRB 060204B: GETS early limit
  43. GRB 060223A:Xinglong optical limits
  44. GRB 060223B: Swift-BAT refined analysis
  45. GRB 060223a: Swift/UVOT refined analysis
  46. GRB 060223B: Swift detection of a bright burst
  47. GRB 060223: Swift-BAT refined analysis
  48. GRB 060223: Swift detection of a burst
  49. Spectral properties of GRB060218/SN2006aj
  50. GRB 060219: Swift-BAT refined analysis
  51. GRB 060218: Decline in r-band flux
  52. GRB060218: UV Detection and Light Curves
  53. GRB060219: SARA Observations
  54. GRB 060219: Swift/UVOT Upper Limits
  55. GRB 060219: Swift-XRT Team refined analysis
  56. GRB 051221B: Swift-XRT Team Refined Analysis
  57. GRB060218: Radio Afterglow Discovery
  58. GRB060219: SDSS pre-burst observations
  59. GRB 060219: Swift-BAT detection of a weak burst
  60. Oddball GRB 060218, transient or GRB?
  61. GRB060218: Swift/XRT Team preliminary analysis of the possible burst
  62. GRB 060218: Pre-burst detection of a possible host galaxy
  63. Further UVOT Observations of the Candidate Optical Afterglow for GRB 060218
  64. GRB 060211B: Swift/UVOT Upper Limits
  65. GRB060218 : SDSS pre-burst observations
  66. GRB 060218: Swift-BAT detection of a possible burst
  67. GRB 060213: optical afterglow not confirmed
  68. Swift UVOT observations of GRB060213
  69. GRB 060211B: Skynet Observations
  70. GRB060213: Swift XRT observations and possible afterglow candidate
  71. GRB 060213: IPN localization
  72. GRB060211B: REM optical and NIR observations
  73. GRB 060211A: Further refined analysis of the Swift burst
  74. GRB 060210: ARC NIR Detection of Afterglow and Possible Host Galaxy
  75. GRB 060211b: P60 Observations
  76. GRB 060211A: Partial refined analysis on the Swift-BAT burst
  77. GRB 050826: Optical Afterglow and Host Galaxy
  78. GRB 060210: Further refined analysis of the Swift-BAT burst
  79. GRB 060211B: Swift/BAT refined analysis
  80. GRB060210: Swift/UVOT Upper Limits
  81. GRB 060211B: Swift-XRT Team refined analysis
  82. GRB 060210: Optical Observations
  83. GRB 060211: Swift detection of a long burst
  84. GRB 060210: Refined analysis of the Swift-BAT burst
  85. GRB060210: Swift XRT Refined Analysis
  86. GRB 060210 : Xinglong and Lulin optical limit
  87. GRB 060210: optical evolution
  88. GRB 060210: Swift detection of a burst
  89. GRB060210: Optical afterglow
  90. GRB 060209 : TAROT optical observation
  91. GRB 060203: Swift/UVOT upper limits
  92. GRB 060121 : WIDGET Pre-trigger limit
  93. GRB060204a: Swift XRT Source is not GRB Afterglow
  94. GRB 060206: optical observations at Asiago
  95. GRB 060206: IR Detection of the Afterglow
  96. GRB 060206: Super-LOTIS observations
  97. GRB060204A: Swift/UVOT observations
  98. GRB 060206: Swift-BAT refined analysis
  99. GRB060206: SDSS Pre-Burst Observations
  100. GRB060206 - Swift UVOT Confirmation of Optical Afterglow

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