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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"

19142 results found.

  1. GRB011130 (XRF011130) SDSS PT i-band observations
  2. XRF011130: Infrared Observations
  3. GRB011130, Radio Observations
  4. GRB011130 (=XRF011130), Optical Observations
  5. XRF011130: NEAT Optical Observations
  6. GRB001109, Radio Monitoring
  7. GRB 011121
  8. GRB 011121: J-band observations
  9. GRB 011121: NIR observations, host galaxy?
  10. GRB010921 - Milagro GeV/TeV Observations
  11. GRB 011121: HST Scheduled
  12. GRB011121: fainter still
  13. GRB011121: UBRI Observations
  14. GRB011121
  15. GRB 011121: Radio Observations
  16. GRB011121: continued decay
  17. GRB 011121: Detection of Bright IR Counterpart
  18. GRB011121: possible redshift, continued decay
  19. GRB011121: fading behavior
  20. GRB011121: possible optical counterpart
  21. XRF011030: J and K band observations
  22. XRF011030: Chandra Observations
  23. GRB 011030: K-band observations
  24. GRB011030: Z-band observations
  25. GRB 011030 R band observations
  26. The X-ray Flash 011030 ('GRB 011030')
  27. Non-triggered burst 011030 ("GRB 011030")
  28. The Radio Afterglow from the X-ray Rich GRB 011030
  29. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  30. GRB 970828: HST Observations of the Host Galaxy
  31. GRB 000131: HST Detection of the Host Galaxy
  32. GRB 970828: HST Observations of the Host Galaxy
  33. GRB010921, optical observation
  34. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  35. GRB011019: Subaru Optical Observations
  36. GRB 011030 I-band Observations
  37. GRB 011030 K-band Observations
  38. GRB010921, optical observations
  39. GRB 011030, WSRT radio observations
  40. GRB 011030, Radio observations
  41. GRB 011030, R-band observations
  42. GRB011019: NEAT Optical Observations
  43. GRB011019: ROTSE-III optical observations
  44. GRB 010921, I-band observations
  45. GRB011019: Optical observations
  46. GRB011019, optical observations -- correction
  47. GRB011019, optical observations
  48. GRB010921: Spectroscopy of the Host Galaxy
  49. GRB 010921: The afterglow of HETE #1761
  50. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  51. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  52. GRB010928(=H1770): Localization of a Long GRB by HETE
  53. GRB010921, negative optical observations
  54. GRB010921 Optical Observations
  55. HETE Trigger #1760 (GRB 010920B?): a new optical source
  56. HETE Trigger #1759 (GRB 010920?) optical observations
  57. GRB001109, Host Galaxy Astrometry
  58. GRB000926, Host Galaxy Observations
  59. GRB001109, Host Galaxy Spectroscopic Observations
  60. GRB000926 Host Galaxy Observations
  61. GRB 010222: HST observations -- host galaxy and late-time decay
  62. GRB 010222 - WHT BVRI images
  63. GRB 010629 Optical Observations
  64. GRB010629: Optical Observations
  65. SGR1900+14: High Fluence Burst Localized by HETE
  66. GRB010629, optical observations
  67. GRB010629: A Burst Localized by HETE
  68. SGR1900+14: Second Burst Localized by HETE
  69. SGR1900+14: A Burst Localized by HETE
  70. SGR1806-20: A Second, Intense Burst Localized by HETE
  71. GRB 00630: Host Galaxy
  72. SGR1806-20: Localization by HETE
  73. GRB000301C: Late-time HST/STIS observation
  74. GRB000418: HST/STIS Second-epoch Observations
  75. GRB010214, optical observations
  76. GRB010427, Gamma Ray Observations
  77. SGR 1900+14: No evidence of extended X-ray emission
  78. SGR 1900+14 : RXTE observations
  79. GRB 010222 /corrections to VBT data
  80. Millimeter observation of SGR 1900+14
  81. Chandra Observations of SGR 1900+14
  82. SGR 1900+14, Chandra observations
  83. Chandra Observations of SGR 1900+14
  84. SGR1900+14, I-band observations
  85. GRB 010326b Optical Observations
  86. GRB010412: Optical observations
  87. GRB010412: Optical observations
  88. GRB010412: BeppoSAX GRBM and WFC observations
  89. GRB Observation Report
  90. GRB 980326: Late-time HST/STIS observations
  91. Further Optical Observations of GRB 010324
  92. GRB010222, CXO X-ray observations
  93. GRB 010326A: Further optical observations
  94. GRB 010326B: Optical observations
  95. GRB010324, optical observations
  96. GRB010326B: Localization by HETE (2nd GRB for this date)
  97. GRB 010326: Optical observations
  98. GRB 010326 optical observations
  99. GRB010326: Refined Localization by HETE
  100. GRB010326: Localization by HETE

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