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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"

19139 results found.

  1. GRB010222, late-time optical observation
  2. GRB 010222 - HEGRA GeV/TeV Observations
  3. GRB010222: Sub-millimeter vanishing act
  4. GRB 010222, Optical Observations
  5. GRB 010222: High-Resolution Keck Spectroscopy
  6. GRB 010214, I-band data
  7. Sub-millimeter Excess/GRB 010222
  8. GRB 010222
  9. GRB 010222 HST/Chandra TOO
  10. GRB010222 further R-band photometry
  11. GRB010222 Optical observations
  12. GRB010222, field photometry
  13. GRB010222 further R-band photometry
  14. GRB010222, possible increase of optical decay slope
  15. GRB 010222 BV optical observations
  16. GRB010220, Optical Observations
  17. GRB010222 R-BAND OBSERVATION
  18. GRB 010220: Near-IR Observations
  19. GRB010214 follow-up from Hanle
  20. GRB 010222: Near-IR Observations
  21. GRB 010222: Optical Observations
  22. GRB010222: Optical decay slope
  23. GRB 010214, Optical Observations
  24. GRB010222: Sub-millimeter detection
  25. GRB010222: R-band fading behavior
  26. GRB010222: Optical Observations
  27. GRB010222, radio observations
  28. GRB010222, optical observations
  29. GRB010222: BeppoSAX/NFI Observations
  30. Redshift of the Optical Transient of GRB010222
  31. GRB010214B,Gamma Ray Observations
  32. GRB010222
  33. GRB010220, Radio and Optical Observations
  34. GRB 010220, simultaneous optical observations
  35. GRB010214, candidate optical afterglow
  36. GRB010214, optical observations
  37. GRB 010214, Optical Observations
  38. GRB010213, Radio Observations
  39. GRB010213 Optical Observation
  40. GRB010213, Radio Observations
  41. J-Band Observation of GRB 010214.
  42. GRB010214, Radio Observations
  43. GRB010214, optical observations
  44. GRB010213, optical observations
  45. GRB010213, Near-IR observations
  46. Possible InfraRed Transient of GRB 010214.
  47. GRB010214 Optical Observation
  48. GRB010214: BeppoSAX/NFI Observations
  49. GRB010213 (HETE) TAROT observations
  50. GRB 010214, optical observations
  51. GRB010213 detected by HETE
  52. GRB010126, TNG R-band observations
  53. GRB010126 Optical Observations
  54. GRB010126 optical observations
  55. GRB010126: Optical observations
  56. GRB 010119, optical observations
  57. GRB010119: Optical observations
  58. Optical Observations of GRB 001018 at Keck
  59. GRB010119, Radio observations
  60. Optical observations of GRB 001018 with JCAM
  61. GRB010103, optical observations
  62. GRB 001204: Ks observations
  63. H band observation of GRB 001212
  64. GRB 001212 possible OA
  65. GRB001204: Optical observations
  66. GRB001204, Radio observations
  67. GRB 001105, further optical observations
  68. GRB001120: Gunn-i observations
  69. GRB001120: Optical observations
  70. GRB001109, optical observations
  71. GRB001120, optical observations
  72. WSRT 4.8 GHz observations of GRB001109
  73. Optical/NIR observations of GRB001109
  74. GRB 001109: deep JHK upper limits
  75. GRB001109: Optical observations
  76. GRB001109: BeppoSAX/NFI Observations
  77. GRB001109, R-band optical observations
  78. GRB001109, Radio observations
  79. GRB 991208: HST Imaging of the Host Galaxy
  80. GRB000926: R-image of the host galaxy
  81. GRB 001025B, I-band observations
  82. GRB001025B, Radio observations
  83. GRB 001025 Optical Observations
  84. GRB001007: Optical observations
  85. GRB001007, Radio observations
  86. GRB001019, Optical Observations
  87. GRB 001018, Possible Radio Afterglow
  88. GRB001018, Gamma Ray Observations
  89. V,R,I band observations of GRB000926
  90. The Likely Optical/Infrared Afterglow of GRB 001011
  91. GRB 001007, BVR-band observations
  92. GRB000926 - Amateur Optical Observations
  93. GRB001007: Optical observations
  94. GRB 000926 : the host galaxy
  95. HETE-2 Launches Successfully
  96. GRB 000926 Chandra Observation
  97. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  98. GRB000926 - Optical observations
  99. GRB000926 - Optical observations
  100. GRB000926 - Optical observations

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