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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"

7396 results found.

  1. GRB021104: Candidate present in DSS
  2. GRB021004, Optical Observations
  3. GRB 021004: radio observations
  4. GRB 021004: Kyoto observation
  5. XRF 020903: Optical observations
  6. Second epoch K band imaging of GRB 020819
  7. GRB020819 : Optical observations at KISO
  8. GRB 020819 : OT candidate - confirmation of non variability
  9. GRB 020819: Optical observations
  10. K band observation of GRB 020819
  11. HETE 2275: Optical observations
  12. GRB020813: Fading X-ray Afterglow Observed with Chandra
  13. GRB020812: optical observations
  14. GRB020813(=H2262): Revised Localization with HETE SXC
  15. GRB 020813, radio detection
  16. GRB 020812 : optical afterglow candidate
  17. GRB020812: optical observations
  18. GRB020813, optical observations
  19. GRB020812: possible afterglow candidate
  20. GRB020812: possible afterglow candidate
  21. GRB020813, astrometric position
  22. GRB020813: Fading of Candidate OT
  23. GRB020813: Candidate Optical Afterglow
  24. GRB020801: Candidate OT present in DSS
  25. GRB020801, optical afterglow candidate
  26. GRB 020705: Optical observations
  27. GRB 020625: Optical observations
  28. GRB 020531: optical photometry of Chandra sources
  29. HETE #2081: Optical observations
  30. GRB 020531/Candidate Redshift
  31. GRB020531: Detection of Candidate Host Galaxy
  32. GRB 020603: Optical observations
  33. GRB 020531 optical observations with TAROT
  34. XRF020427: Chandra Observations and Candidate X-ray Counterparts
  35. GRB020331: Third Epoch and Revised Second Epoch Optical
  36. GRB 020418: Optical observations
  37. GRB 020418: Optical observations
  38. GRB020410: BeppoSAX NFI observations refined analysis
  39. GRB 020409: Optical observations
  40. GRB020406(?), optical observations
  41. GRB020331: Confirmation of Afterglow Candidate with Magellan
  42. GRB 020321: Candidate X-ray Counterparts
  43. ASM GRB candidate 020406 refined error box
  44. GRB020331: Optical Observations of Afterglow Candidate
  45. GRB020405: OT observations
  46. GRB 020331: Candidate Optical Afterglow
  47. GRB 020405: Decay index
  48. GRB020405, Radio Observations
  49. GRB020405: VLT spectroscopy
  50. Fading Optical Afterglow and Possible Host Galaxy of GRB 020405
  51. GRB 020405, U-band observations
  52. GRB 020405: Optical afterglow candidate
  53. GRB 020331: NIR Observations
  54. GRB020331 NIR observation at KPNO (re-submission)
  55. GRB02033 NIR observation at KPNO
  56. GRB 020331, NIR observations
  57. GRB 020331: Optical observations
  58. SN 2002ap - peak brightness date (SN/GRB?)
  59. GRB 020322: Optical Observations
  60. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  61. GRB 020321: Optical observations
  62. GRB020322: Candidate Optical Afterglow
  63. GRB 020322: Optical candidate
  64. GRB020305: NIR observations
  65. GRB 020305: Optical Observations
  66. GRB020305: Properties of the Candidate Optical Afterglow
  67. GRB020305: Subaru Optical Observations
  68. GRB 020305: Optical observations
  69. GRB 020305: Candidate optical afterglow
  70. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  71. GRB optical counterpart candidate in GCN 1217 is M dwarf
  72. GRB011212: Optical observations at Gunma
  73. GRB 011211, spectrum and optical photometry
  74. GRB 011212: optical observation at Oslo (relayed)
  75. GRB 011211: BVRi-band photometry
  76. GRB 011130, K band observations
  77. GRB011130 (=XRF011130), Optical Observations
  78. GRB011121: UBRI Observations
  79. GRB 011030 I-band Observations
  80. GRB 011030 K-band Observations
  81. GRB010921, negative optical observations
  82. Probable SGR or Short Duration GRB Detected by HETE
  83. GRB 010629 Optical Observations
  84. SGR1900+14
  85. Optical Observations of GRB 010324
  86. GRB 010214, I-band data
  87. GRB010222 further R-band photometry
  88. GRB010222 further R-band photometry
  89. GRB010220, Optical Observations
  90. GRB 010220: Near-IR Observations
  91. GRB010214 follow-up from Hanle
  92. GRB 010222: Near-IR Observations
  93. GRB010214, candidate optical afterglow
  94. GRB 010214, Optical Observations
  95. GRB010213, Radio Observations
  96. GRB010214 Optical Observation
  97. GRB 010214, optical observations
  98. HETE Status
  99. GRB010126 opt. obs.
  100. GRB010126 Optical Observations

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