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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"

42958 results found.

  1. GRB041211, Faulkes Telescope optical observation
  2. GRB041211, BVRcIc field calibration
  3. GRB 041211: Infrared Observations
  4. GRB 041211: KAIT observations
  5. GRB 041211: Optical follow-up in East Asian region
  6. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  7. GRB041211: P60 optical imaging
  8. GRB970815: Discovery of Optical Afterglow
  9. Distribution of IBAS Alerts for NON-GRB sources
  10. Triangulation of short GRB 041116 (large error box)
  11. GRB041015: Near-Infrared observations
  12. GRB 040924: Afterglow Color
  13. GRB 041006: GETS Optical Afterglow Observation
  14. Summary of the recent bursts from SGR 1806-20
  15. GRB 041006: Optical Observations
  16. GRB041006, late-time optical photometry
  17. IBAS GRB Alert # 2034
  18. GRB041006: RTT150 Optical Observations
  19. GRB041015 : Multi epoch optical observations
  20. HST Observations: XRF 040701 and 040812
  21. Bright bursts from SGR1806-20
  22. GRB 041016: BOOTES-2 simultaneous observation
  23. GRB041006: RTT150 Optical Observations
  24. GRB 041016: Optical limits
  25. GRB 041016: Optical limits in V, R, I
  26. GRB 041016:Optical limit during first minute
  27. GRB041016: MASTER: Optical observations
  28. GRB 041015: Optical Observations at Rikubetsu
  29. GRB041006: Near Infrared observations
  30. GRB 041016: Optical limit
  31. GRB 041015 R band observations
  32. GRB040924, BVRcIc field calibration
  33. GRB041015: MASTER: Optical observations
  34. GRB041006: Fading X-ray Afterglow Observed with Chandra
  35. GRB 041015: Optical limit at Osaka University
  36. GRB041015 : Optical follow-up at Kiso
  37. GRB 041015 - A long GRB detected by INTEGRAL
  38. GRB 041006 R observations in Loiano
  39. GRB041006: VLT observations of the afterglow and host galaxy
  40. GRB041006: Optical observations and Potential host galaxy
  41. GRB041006, BVRcIc field calibration
  42. GRB 040924: VLT spectroscopy
  43. GRB 041006: SARA afterglow observations
  44. GRB041006, optical observation in CrAO
  45. Search for SN light in XRF 040912 with MEGACAM
  46. GRB 040916: Afterglow Color at Early Times
  47. GRB 041006 Optical afterglow observations
  48. IBAS GRB Alert # 2010
  49. GRB 041006: BR observations with VATT
  50. GRB 041006: Redshift confirmed
  51. GRB 041006: Colour measurement
  52. GRB041006: break in the light curve
  53. GRB 041006: Radio Observations
  54. GRB 041006 : Optical follow-up observation at TAROT
  55. GRB041006: Optical photometry and spectroscopy at TNG
  56. GRB 041006: presice astrometry
  57. GRB041006 (= H3570): Chandra Observations In Progress
  58. GRB 041006 : optical observation at Bisei
  59. GRB041006, optical I observation
  60. GRB041006 (=HETE3570): optical observations
  61. ROTSE-IIIa Observations of GRB 041006
  62. GRB041006, optical observation
  63. GRB041006: MASTER optical observations
  64. GRB 041006: Optical decay
  65. GRB 041006 (=H3570): An X-Ray Rich GRB Localized in Real Time by HETE
  66. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  67. GRB041006: Fading of optical afterglow candidate
  68. GRB 041006 : Optical follow-up observation at KISO
  69. GRB 041006: Finding chart
  70. GRB 041006: Optical afterglow candidate
  71. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  72. Very strong outburst from SGR 1806-20 detected with INTEGRAL
  73. XRF 020903: Observations of the Host Galaxy
  74. SGR 1806-20 still active
  75. GRB 040924: Second Epoch WSRT Radio Observations
  76. radio observations, GRB 040924
  77. IBAS Alert 1991. Not a real GRB
  78. GRB040929: MASTER optical observations
  79. Konus-Wind and Helicon-Coronas-F observations of GRB040924
  80. GRB040924,optical observation
  81. GRB040924, RTT150 optical observation
  82. GRB040924,optical observation
  83. GRB 040924: detection of possible host galaxy by Subaru
  84. GRB040924, RTT150 optical observation
  85. GRB040924: KAIT observations
  86. GRB 040924: WSRT Radio Observations
  87. GRB 040924: NIR finding chart
  88. GRB040924 : Optical candidate observations at Lulin observatory
  89. GRB040924 : Optical candidate observations at Lulin observatory
  90. GRB 040924: Subaru NIR observation
  91. GRB040924: Optical afterglow properties
  92. GRB 040924: RTT150 optical observations
  93. GRB 040924, optical follow-up
  94. GRB040924: MASTER: OT decay
  95. GRB040924: MASTER Optical observations
  96. IPN triangulation of GRB040924 (H3564)
  97. GRB 040924(=H3564): A Short, Bright GRB Localized in Real Time by HETE
  98. GRB040924 (H3564): Optical afterglow candidate
  99. XRF 040912: Radio Observations
  100. XRF 040916: Radio Observations

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