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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"

42961 results found.

  1. GRB041211: Continued P60 Observations
  2. GRB041211: RAPTOR observations
  3. GRB041211: Ashra Prototype optical observation
  4. GRB041211, Faulkes Telescope optical observation
  5. GRB041211, BVRcIc field calibration
  6. GRB 041211: Infrared Observations
  7. GRB 041211: KAIT observations
  8. GRB 041211: Optical follow-up in East Asian region
  9. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  10. GRB041211: P60 optical imaging
  11. GRB970815: Discovery of Optical Afterglow
  12. Distribution of IBAS Alerts for NON-GRB sources
  13. Triangulation of short GRB 041116 (large error box)
  14. GRB041015: Near-Infrared observations
  15. GRB 040924: Afterglow Color
  16. GRB 041006: GETS Optical Afterglow Observation
  17. Summary of the recent bursts from SGR 1806-20
  18. GRB 041006: Optical Observations
  19. GRB041006, late-time optical photometry
  20. IBAS GRB Alert # 2034
  21. GRB041006: RTT150 Optical Observations
  22. GRB041015 : Multi epoch optical observations
  23. HST Observations: XRF 040701 and 040812
  24. Bright bursts from SGR1806-20
  25. GRB 041016: BOOTES-2 simultaneous observation
  26. GRB041006: RTT150 Optical Observations
  27. GRB 041016: Optical limits
  28. GRB 041016: Optical limits in V, R, I
  29. GRB 041016:Optical limit during first minute
  30. GRB041016: MASTER: Optical observations
  31. GRB 041015: Optical Observations at Rikubetsu
  32. GRB041006: Near Infrared observations
  33. GRB 041016: Optical limit
  34. GRB 041015 R band observations
  35. GRB040924, BVRcIc field calibration
  36. GRB041015: MASTER: Optical observations
  37. GRB041006: Fading X-ray Afterglow Observed with Chandra
  38. GRB 041015: Optical limit at Osaka University
  39. GRB041015 : Optical follow-up at Kiso
  40. GRB 041015 - A long GRB detected by INTEGRAL
  41. GRB 041006 R observations in Loiano
  42. GRB041006: VLT observations of the afterglow and host galaxy
  43. GRB041006: Optical observations and Potential host galaxy
  44. GRB041006, BVRcIc field calibration
  45. GRB 040924: VLT spectroscopy
  46. GRB 041006: SARA afterglow observations
  47. GRB041006, optical observation in CrAO
  48. Search for SN light in XRF 040912 with MEGACAM
  49. GRB 040916: Afterglow Color at Early Times
  50. GRB 041006 Optical afterglow observations
  51. IBAS GRB Alert # 2010
  52. GRB 041006: BR observations with VATT
  53. GRB 041006: Redshift confirmed
  54. GRB 041006: Colour measurement
  55. GRB041006: break in the light curve
  56. GRB 041006: Radio Observations
  57. GRB 041006 : Optical follow-up observation at TAROT
  58. GRB041006: Optical photometry and spectroscopy at TNG
  59. GRB 041006: presice astrometry
  60. GRB041006 (= H3570): Chandra Observations In Progress
  61. GRB 041006 : optical observation at Bisei
  62. GRB041006, optical I observation
  63. GRB041006 (=HETE3570): optical observations
  64. ROTSE-IIIa Observations of GRB 041006
  65. GRB041006, optical observation
  66. GRB041006: MASTER optical observations
  67. GRB 041006: Optical decay
  68. GRB 041006 (=H3570): An X-Ray Rich GRB Localized in Real Time by HETE
  69. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  70. GRB041006: Fading of optical afterglow candidate
  71. GRB 041006 : Optical follow-up observation at KISO
  72. GRB 041006: Finding chart
  73. GRB 041006: Optical afterglow candidate
  74. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  75. Very strong outburst from SGR 1806-20 detected with INTEGRAL
  76. XRF 020903: Observations of the Host Galaxy
  77. SGR 1806-20 still active
  78. GRB 040924: Second Epoch WSRT Radio Observations
  79. radio observations, GRB 040924
  80. IBAS Alert 1991. Not a real GRB
  81. GRB040929: MASTER optical observations
  82. Konus-Wind and Helicon-Coronas-F observations of GRB040924
  83. GRB040924,optical observation
  84. GRB040924, RTT150 optical observation
  85. GRB040924,optical observation
  86. GRB 040924: detection of possible host galaxy by Subaru
  87. GRB040924, RTT150 optical observation
  88. GRB040924: KAIT observations
  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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