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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"

26007 results found.

  1. GRB 060322: IAC80 optical observations
  2. GRB 060322: Swift XRT afterglow candidate
  3. GRB060323: P60 Observations
  4. GRB 060323: Swift/UVOT Observations
  5. GRB 060323: optical afterglow confirmed
  6. GRB060323: NOT observations
  7. GRB 060323: Optical Observations
  8. GRB 060323: Refined analysis of the Swift-BAT burst
  9. GRB 060323: optical observations at TNG
  10. GRB 060323: BVRI observations at Tautenburg, aftreglow candidate
  11. GRB 060322: Refined analysis of the Swift-BAT burst
  12. GRB060323, optical observation
  13. GRB060323 - SDSS Pre-Burst Observations
  14. GRB 060323: Swift detection of a burst with a possible optical afterglow
  15. GRB 060322: Swift-BAT detection of a 200-sec burst
  16. GRB 060218/SN 2006aj, LNA optical observation
  17. GRB060218: Refined photometric calibration of comparison stars
  18. GRB 060319: WHT K-band candidate afterglow
  19. GRB060319: Swift/UVOT upper limits
  20. GRB 060319: Swift-BAT refined analysis
  21. GRB 060319 optical observations at TNG
  22. GRB060319 : Liverpool Telescope optical limit
  23. GRB060319 - SDSS Pre-burst Observations
  24. GRB060313: Radio Observations
  25. GRB 060313: early afterglow NIR upper limits with REM
  26. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  27. GRB 060313: Swift/UVOT Observations
  28. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  29. GRB 060313, SMARTS optical counterpart?
  30. GRB 060313, SMARTS optical/IR observations
  31. GRB060313: optical and near infrared observations with REM
  32. GRB060218: SARA Observations of SN2006aj
  33. GRB 060312: Refined analysis of the Swift-BAT burst
  34. GRB 060218/SN 2006aj, high resolution spectra
  35. GRB 060312: Swift XRT team refined analysis
  36. GRB060306: APO Ks-band Imaging Observations
  37. GRB 060312: ROTSE-III Optical Limits
  38. Bright short hard GRB 060303: IPN localization and Konus spectrum
  39. GRB060219: Liverpool Telescope observations
  40. GRB 060306: MAGNUM observations
  41. GRB060218: analysis of the XMM-Newton observation
  42. Swift/UVOT observations of GRB060306
  43. GRB 060306: Swift-BAT refined analysis
  44. GRB 060306: Swift-XRT team refined analysis
  45. GRB 060306: Swift detection of a bright burst
  46. GRB060218: Ep,i - Eiso correlation
  47. GRB060223b: optical limit
  48. GRB 060223b: Swift/UVOT Upper Limits
  49. GRB 060218/SN 2006aj: K-380 optical observations
  50. GRB 060218/SN 2006aj, SMARTS optical/IR observations
  51. GRB 060223B: Swift XRT possible afterglow
  52. GRB 060218/SN 2006aj: ABT observations
  53. GRB 060218/SN 2006aj: REM optical and near-infrared observations
  54. GRB 060218 : Radio upper limits from GMRT
  55. GRB 060218/SN 2006aj: RBO optical observations
  56. GRB 060204B: GETS early limit
  57. GRB 060223A:Xinglong optical limits
  58. GRB 060223B: Swift-BAT refined analysis
  59. GRB 060223a: Swift/UVOT refined analysis
  60. GRB 060223B: Swift detection of a bright burst
  61. GRB 060223: Swift-BAT refined analysis
  62. GRB 060223: Swift detection of a burst
  63. Spectral properties of GRB060218/SN2006aj
  64. GRB 060219: Swift-BAT refined analysis
  65. GRB 060218: Decline in r-band flux
  66. GRB060218: UV Detection and Light Curves
  67. GRB060219: SARA Observations
  68. GRB 060219: Swift/UVOT Upper Limits
  69. GRB 060219: Swift-XRT Team refined analysis
  70. GRB 051221B: Swift-XRT Team Refined Analysis
  71. GRB060218: Radio Afterglow Discovery
  72. GRB060219: SDSS pre-burst observations
  73. GRB 060219: Swift-BAT detection of a weak burst
  74. Oddball GRB 060218, transient or GRB?
  75. GRB060218: Swift/XRT Team preliminary analysis of the possible burst
  76. GRB 060218: Pre-burst detection of a possible host galaxy
  77. Further UVOT Observations of the Candidate Optical Afterglow for GRB 060218
  78. GRB 060211B: Swift/UVOT Upper Limits
  79. GRB060218 : SDSS pre-burst observations
  80. GRB 060218: Swift-BAT detection of a possible burst
  81. GRB 060213: optical afterglow not confirmed
  82. Swift UVOT observations of GRB060213
  83. GRB 060211B: Skynet Observations
  84. GRB060213: Swift XRT observations and possible afterglow candidate
  85. GRB 060213: IPN localization
  86. GRB060211B: REM optical and NIR observations
  87. GRB 060211A: Further refined analysis of the Swift burst
  88. GRB 060210: ARC NIR Detection of Afterglow and Possible Host Galaxy
  89. GRB 060211b: P60 Observations
  90. GRB 060211A: Partial refined analysis on the Swift-BAT burst
  91. GRB 050826: Optical Afterglow and Host Galaxy
  92. GRB 060210: Further refined analysis of the Swift-BAT burst
  93. GRB 060211B: Swift/BAT refined analysis
  94. GRB060210: Swift/UVOT Upper Limits
  95. GRB 060211B: Swift-XRT Team refined analysis
  96. GRB 060210: Optical Observations
  97. GRB 060211: Swift detection of a long burst
  98. GRB 060210: Refined analysis of the Swift-BAT burst
  99. GRB060210: Swift XRT Refined Analysis
  100. GRB 060210 : Xinglong and Lulin optical limit

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