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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.

Lucene Examples (click to copy):

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

3036 results found.

  1. GRB 060707: Swift-XRT refined analysis
  2. GRB050326: Host Galaxy Candidates
  3. GRB050124: Possible Host Galaxy
  4. GRB050223: Host Galaxy
  5. GRB060512: near IR observations
  6. GRB060614: Swift-XRT refined analysis
  7. GRB 060602A: Swift/XRT analysis
  8. GRB 060605: Swift-XRT Team refined analysis
  9. GRB 060604: Swift-XRT Team refined analysis
  10. GRB 060526: Break in X-ray light curve
  11. XMM-Newton observation of GRB060510b
  12. GRB 060515: NIR observation
  13. GRB060515: P200 NIR Observations
  14. GRB 060515: Swift/XRT Team refined analysis
  15. GRB 060515: Swift/XRT position
  16. GRB 060512: Subaru NIR observation
  17. GRB060512: Swift XRT Team refined analysis
  18. GRB 060512: Detection of NIR afterglow
  19. GRB 060505: X-ray afterglow - Correction -
  20. GRB 060505: X-ray afterglow
  21. GRB060510B: Swift XRT refined analysis
  22. GRB060510A: XRT refined analysis
  23. GRB060502B: improvement in the XRT afterglow position
  24. GRB 060505: Swift XRT Team Refined Analysis
  25. GRB 060306: Further Analysis of SOAR and APO NIR Observations
  26. GRB 060505: Swift XRT afterglow canditate position
  27. GRB060502B: Swift XRT Team refined analysis
  28. GRB060502: Swift-XRT refined analysis
  29. GRB060428B: Swift XRT Team refined analysis
  30. GRB 060421: Swift-XRT refined analysis
  31. Erratum of GCN 4983 for GRB 060418 IR follow-up
  32. GRB 060418 : IR afterglow observations
  33. GRB 060418: JHKs PAIRITEL Observations of Afterglow
  34. GRB060418: Swift XRT Team Refined Analysis
  35. GRB060403: XRT refined analysis
  36. GRB 060322: Confirmation of Swift XRT afterglow
  37. GRB 060322: Swift XRT afterglow candidate
  38. GRB 060313: early afterglow NIR upper limits with REM
  39. GRB 060312: Swift XRT team refined analysis
  40. GRB060306: APO Ks-band Imaging Observations
  41. GRB 060306: SOAR Ks Observations
  42. GRB060218: analysis of the XMM-Newton observation
  43. GRB 060223B: Swift XRT possible afterglow
  44. GRB 060223: Swift/UVOT Confirmation of Optical Afterglow
  45. GRB 060219: Swift-XRT Team refined analysis
  46. GRB 051221B: Swift-XRT Team Refined Analysis
  47. GRB 060210: ARC NIR Detection of Afterglow and Possible Host Galaxy
  48. GRB 060211B: Swift-XRT Team refined analysis
  49. GRB060210: Swift XRT Refined Analysis
  50. GRB 060206: near-infrared observations (JK' imaging)
  51. GRB 060206: IR Detection of the Afterglow
  52. GRB060204a: Swift XRT Detection of an Afterglow Candidate
  53. GRB 060204C: XRT analysis of Swift J061223.0+701243.9
  54. Swift XRT Observation of GRB 060204C
  55. GRB060204B: Swift XRT Team Refined Analysis
  56. GRB 060203: IR Counterpart
  57. Swift BAT Trigger 180151: Swift XRT source detection
  58. GRB 060121: Confirmation of NIR Afterglow
  59. GRB 060123: Swift refined analysis of an unusual GRB
  60. GRB060105: refined analysis of the Suzaku observation
  61. GRB 060121: Probable Detection of NIR Afterglow
  62. GRB060124: detailed XRT analysis
  63. GRB060123: Optical and IR Imaging
  64. GRB 060123: Swift detection of a very long, faint burst
  65. GRB 060121: Swift/UVOT upper limits
  66. GRB 060121: Swift XRT refined analysis
  67. GRB 060121: Swift XRT refined position
  68. GRB 060121: Infrared Observations
  69. GRB 060116: possible I-J dropout
  70. GRB 060110: XRT position and analysis
  71. GRB 060114: Swift XRT upper limit
  72. GRB 060108: further analysis of VLT images
  73. GRB 060111B: Swift XRT refined analysis
  74. GRB060111 : XRT refined analysis
  75. GRB 060110: IR Candidate Afterglow
  76. GRB 060108: ISAS early observations and near IR upper limit
  77. GRB060108: P200 Ks Observations
  78. GRB 060105: ISAS observations and near IR upper limit
  79. Swift-BAT trigger 175653 is not an astrophysical source
  80. GRB051016: analysis of the XMM-Newton observation
  81. GRB 051221A: Chandra Afterglow Position
  82. GRB 051221: Swift XRT refined analysis
  83. GRB 051215: near-infrared observations
  84. GRB 051211B: Swift XRT confirmation of the afterglow
  85. GRB 051211B: Swift XRT Observations
  86. GRB 051210: Swift XRT refined analysis
  87. GRB 051117b: NIR observations
  88. GRB051117A : XRT refined analysis
  89. GRB051114: results of the Swift-XRT observation
  90. GRB051111: XRT preliminary analysis
  91. GRB 051111a: IR photometry
  92. GRB051109B: XRT refined analysis
  93. GRB051109A: XRT refined analysis
  94. GRB 051109a: IR Photometry and Astrometry
  95. GRB 051109a: IR Detections
  96. GRB051028: Swift-XRT refined analysis
  97. XRT observations of GRB 051105A
  98. GRB 051022: XRT Refined Spectral and Temporal Analysis
  99. Chandra Observations of GRB 051022
  100. GRB051012: Swift-XRT analysis

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