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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

37169 results found.

  1. GRB041217: Infrared Observations
  2. GRB041217: The First GRB Located On-Board Swift
  3. GRB041211: Faulkes Telescope continued optical monitoring
  4. Optical Transient in Lynx not a GRB
  5. Optical transient (GRB?) in Lynx
  6. Optical transient (GRB?) in Lynx, UT Dec 11.4436
  7. GRB041211: Continued P60 Observations
  8. GRB041211: RAPTOR observations
  9. GRB041211: Ashra Prototype optical observation
  10. GRB041211, Faulkes Telescope optical observation
  11. GRB041211, BVRcIc field calibration
  12. GRB 041211: Infrared Observations
  13. GRB 041211: KAIT observations
  14. GRB 041211: Optical follow-up in East Asian region
  15. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  16. GRB041211: P60 optical imaging
  17. GRB970815: Discovery of Optical Afterglow
  18. Distribution of IBAS Alerts for NON-GRB sources
  19. Triangulation of short GRB 041116 (large error box)
  20. GRB 040924: Afterglow Color
  21. GRB 041006: GETS Optical Afterglow Observation
  22. Summary of the recent bursts from SGR 1806-20
  23. GRB 041006: Optical Observations
  24. GRB041006, late-time optical photometry
  25. IBAS GRB Alert # 2034
  26. GRB041006: RTT150 Optical Observations
  27. Bright bursts from SGR1806-20
  28. GRB 041016: BOOTES-2 simultaneous observation
  29. GRB041006: RTT150 Optical Observations
  30. GRB 041016: Optical limits
  31. GRB 041016: Optical limits in V, R, I
  32. GRB 041016:Optical limit during first minute
  33. GRB041016: MASTER: Optical observations
  34. GRB 041015: Optical Observations at Rikubetsu
  35. GRB041006: Near Infrared observations
  36. GRB 041016: Optical limit
  37. GRB 041015 R band observations
  38. GRB040924, BVRcIc field calibration
  39. GRB041015: MASTER: Optical observations
  40. GRB041015,optical observation
  41. GRB 041015: Optical limit at Osaka University
  42. GRB041015 : Optical follow-up at Kiso
  43. GRB 041015 - A long GRB detected by INTEGRAL
  44. GRB 041006 R observations in Loiano
  45. GRB041006: VLT observations of the afterglow and host galaxy
  46. GRB041006: Optical observations and Potential host galaxy
  47. GRB041006, BVRcIc field calibration
  48. GRB 040924: VLT spectroscopy
  49. GRB 041006: SARA afterglow observations
  50. Search for SN light in XRF 040912 with MEGACAM
  51. GRB 040916: Afterglow Color at Early Times
  52. GRB 041006 Optical afterglow observations
  53. IBAS GRB Alert # 2010
  54. GRB 041006: BR observations with VATT
  55. GRB 041006: Redshift confirmed
  56. GRB041006: Liverpool Telescope optical observations
  57. GRB 041006: Colour measurement
  58. GRB041006: break in the light curve
  59. GRB 041006: Radio Observations
  60. GRB041006, further submilllimetre observations
  61. GRB 041006 : optical follow-up observation at Lulin Observatory
  62. GRB 041006 : Optical follow-up observation at TAROT
  63. GRB041006: Optical photometry and spectroscopy at TNG
  64. GRB 041006: presice astrometry
  65. GRB041006 (= H3570): Chandra Observations In Progress
  66. GRB 041006 : optical observation at Bisei
  67. GRB041006 (=HETE3570): optical observations
  68. ROTSE-IIIa Observations of GRB 041006
  69. GRB041006, submillimetre observations
  70. GRB041006: MASTER optical observations
  71. GRB 041006: Optical decay
  72. GRB 041006 (=H3570): An X-Ray Rich GRB Localized in Real Time by HETE
  73. GRB 041006 : Optical follow-up observation at KISO
  74. GRB 041006: Finding chart
  75. GRB 041006: Optical afterglow candidate
  76. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  77. XRF 020903: Observations of the Host Galaxy (authors)
  78. GRB 040924: Second Epoch WSRT Radio Observations
  79. radio observations, GRB 040924
  80. IBAS Alert 1991. Not a real GRB
  81. GRB040929,optical observation
  82. GRB040929: MASTER optical observations
  83. GRB040924,optical observation
  84. GRB040924, RTT150 optical observation
  85. GRB 040924: detection of possible host galaxy by Subaru
  86. GRB040924, RTT150 optical observation
  87. GRB040924: KAIT observations
  88. GRB040924: Afterglow magnitude at t=17.5hr
  89. GRB 040924: WSRT Radio Observations
  90. GRB 040924: NIR finding chart
  91. GRB040924 : Optical candidate observations at Lulin observatory
  92. GRB040924 : Optical candidate observations at Lulin observatory
  93. GRB 040924: Subaru NIR observation
  94. GRB040924: Optical afterglow properties
  95. GRB 040924: RTT150 optical observations
  96. GRB 040924, optical follow-up
  97. GRB040924: MASTER: OT decay
  98. GRB040924: MASTER Optical observations
  99. IPN triangulation of GRB040924 (H3564)
  100. GRB 040924(=H3564): A Short, Bright GRB Localized in Real Time by HETE

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