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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').

24546 results found.

  1. GRB 060223: Swift detection of a burst
  2. Spectral properties of GRB060218/SN2006aj
  3. GRB 060219: Swift-BAT refined analysis
  4. GRB 060218: Decline in r-band flux
  5. GRB060218: UV Detection and Light Curves
  6. GRB060219: SARA Observations
  7. GRB 060219: Swift/UVOT Upper Limits
  8. GRB 060219: Swift-XRT Team refined analysis
  9. GRB 051221B: Swift-XRT Team Refined Analysis
  10. GRB060218: Radio Afterglow Discovery
  11. GRB060219: SDSS pre-burst observations
  12. GRB 060219: Swift-BAT detection of a weak burst
  13. Oddball GRB 060218, transient or GRB?
  14. GRB060218: Swift/XRT Team preliminary analysis of the possible burst
  15. GRB 060218: Pre-burst detection of a possible host galaxy
  16. Further UVOT Observations of the Candidate Optical Afterglow for GRB 060218
  17. GRB 060211B: Swift/UVOT Upper Limits
  18. GRB060218 : SDSS pre-burst observations
  19. GRB 060218: Swift-BAT detection of a possible burst
  20. GRB 060213: optical afterglow not confirmed
  21. Swift UVOT observations of GRB060213
  22. GRB 060211B: Skynet Observations
  23. GRB060213: Swift XRT observations and possible afterglow candidate
  24. GRB 060213: IPN localization
  25. GRB060211B: REM optical and NIR observations
  26. GRB 060211A: Further refined analysis of the Swift burst
  27. GRB 060210: ARC NIR Detection of Afterglow and Possible Host Galaxy
  28. GRB 060211b: P60 Observations
  29. GRB 060211A: Partial refined analysis on the Swift-BAT burst
  30. GRB 050826: Optical Afterglow and Host Galaxy
  31. GRB 060210: Further refined analysis of the Swift-BAT burst
  32. GRB 060211B: Swift/BAT refined analysis
  33. GRB060210: Swift/UVOT Upper Limits
  34. GRB 060211B: Swift-XRT Team refined analysis
  35. GRB 060210: Optical Observations
  36. GRB 060211: Swift detection of a long burst
  37. GRB 060210: Refined analysis of the Swift-BAT burst
  38. GRB060210: Swift XRT Refined Analysis
  39. GRB 060210 : Xinglong and Lulin optical limit
  40. GRB 060210: optical evolution
  41. GRB 060210: Swift detection of a burst
  42. GRB060210: Optical afterglow
  43. GRB 060209 : TAROT optical observation
  44. GRB 060203: Swift/UVOT upper limits
  45. GRB 060121 : WIDGET Pre-trigger limit
  46. GRB060204a: Swift XRT Source is not GRB Afterglow
  47. GRB 060206: optical observations at Asiago
  48. GRB 060206: IR Detection of the Afterglow
  49. GRB 060206: Super-LOTIS observations
  50. GRB060204A: Swift/UVOT observations
  51. GRB 060206: Swift-BAT refined analysis
  52. GRB060206: SDSS Pre-Burst Observations
  53. GRB060206 - Swift UVOT Confirmation of Optical Afterglow
  54. GRB060206: Swift-BAT detection of a burst
  55. GRB 060204C: XRT analysis of Swift J061223.0+701243.9
  56. GRB060204C: optical observation
  57. GRB 060204A: Swift XRT upper limit
  58. GRB 060204A: FRAM optical observations
  59. GRB060204B: Swift/UVOT refined analysis
  60. GRB 060204C: optical observations
  61. Swift XRT Observation of GRB 060204C
  62. GRB 060204B: Swift-BAT refined analysis
  63. GRB 060204B: ART early limit
  64. GRB 060204b: Keck/LRIS Afterglow Confirmation
  65. GRB 060204C: Liverpool Telescopes optical limit
  66. GRB 060204C: Swift-BAT detection of a burst
  67. GRB 060204A: further INTEGRAL results
  68. GRB060204B, optical observation
  69. GRB060204B - SDSS pre-burst observations
  70. GRB 060203: Swift-BAT refined analysis
  71. GRB 060204B: Swift detection of a burst
  72. GRB 060202: UKIRT/WFCAM K-band and KeckI/LRIS I-band Observation
  73. GRB 060203: RTT150 optical observations
  74. GRB 060203: IR Counterpart
  75. Possible GRB 060203: optical observations at Asiago
  76. GRB 060202: PROMPT Observations
  77. GRB 060202: GETS observation
  78. GRB 060202: Gemini-N J, H, K_s observations
  79. GRB 060202: Near-IR Observation with UKIRT/WFCAM
  80. GRB 060202: Optical Afterglow Candidate from Keck/LRIS
  81. GRB 060202: Refined analysis of the Swift-BAT burst
  82. GRB060202, optical observation
  83. GRB 060202: Swift/UVOT upper limits
  84. GRB 060121: Gemini Late-time Observations
  85. GRB 060130: PROMPT Observations
  86. GRB060130: Further R-band imaging
  87. GRB 060130: Swift/XRT observation
  88. GRB 060123: Gemini spectroscopy of the putative host galaxy
  89. GRB060130: Optical imaging
  90. GRB060130: REM infrared observations
  91. GRB 060130, SMARTS optical observations
  92. GRB 060130: FRAM optical observations
  93. GRB 060130: further INTEGRAL IBIS results
  94. GRB 060121: Confirmation of NIR Afterglow
  95. GRB 060123: Swift refined analysis of an unusual GRB
  96. GRB060124, BVRcIc field calibration
  97. GRB 060121: Probable Detection of NIR Afterglow
  98. GRB 060116 HST observations
  99. GRB 060124: HETE detection and spectrum of the main peak
  100. GRB060124: detailed XRT analysis

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