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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"

37704 results found.

  1. GRB 041218: Optical Observation
  2. GRB 041219: Infrared Afterglow Candidate
  3. GRB041219, BVRcIc field calibration
  4. GRB 041219: Infrared Afterglow Candidate
  5. GRB041218, BVRcIc field calibration
  6. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  7. GRB041219: P60 Optical Observations
  8. GRB 041219 - A long GRB detected by INTEGRAL
  9. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  10. GRB 041217: PROMPT Observations
  11. GRB041218: optical observations
  12. GRB041217: optical limit 30 min after GRB
  13. GRB 041218; optical candidate
  14. GRB 041218: Optical observations
  15. GRB 041217: LCO40 Optical Observations and Possible Candidates
  16. GRB 041218 - A long GRB detected by integral
  17. GRB041217: Optical Observations
  18. GRB041217: P60 Optical Observations
  19. GRB041217: Infrared Observations
  20. GRB041217: The First GRB Located On-Board Swift
  21. GRB041211: Faulkes Telescope continued optical monitoring
  22. Optical Transient in Lynx not a GRB
  23. Optical transient (GRB?) in Lynx
  24. Optical transient (GRB?) in Lynx, UT Dec 11.4436
  25. GRB041211: Continued P60 Observations
  26. GRB041211: RAPTOR observations
  27. GRB041211: Ashra Prototype optical observation
  28. GRB041211, Faulkes Telescope optical observation
  29. GRB041211, BVRcIc field calibration
  30. GRB 041211: Infrared Observations
  31. GRB 041211: KAIT observations
  32. GRB 041211: Optical follow-up in East Asian region
  33. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  34. GRB041211: P60 optical imaging
  35. GRB970815: Discovery of Optical Afterglow
  36. Distribution of IBAS Alerts for NON-GRB sources
  37. Triangulation of short GRB 041116 (large error box)
  38. GRB 040924: Afterglow Color
  39. GRB 041006: GETS Optical Afterglow Observation
  40. Summary of the recent bursts from SGR 1806-20
  41. GRB 041006: Optical Observations
  42. GRB041006, late-time optical photometry
  43. IBAS GRB Alert # 2034
  44. GRB041006: RTT150 Optical Observations
  45. Bright bursts from SGR1806-20
  46. GRB 041016: BOOTES-2 simultaneous observation
  47. GRB041006: RTT150 Optical Observations
  48. GRB 041016: Optical limits
  49. GRB 041016: Optical limits in V, R, I
  50. GRB 041016:Optical limit during first minute
  51. GRB041016: MASTER: Optical observations
  52. GRB 041015: Optical Observations at Rikubetsu
  53. GRB041006: Near Infrared observations
  54. GRB 041016: Optical limit
  55. GRB 041015 R band observations
  56. GRB040924, BVRcIc field calibration
  57. GRB041015: MASTER: Optical observations
  58. GRB041015,optical observation
  59. GRB 041015: Optical limit at Osaka University
  60. GRB041015 : Optical follow-up at Kiso
  61. GRB 041015 - A long GRB detected by INTEGRAL
  62. GRB 041006 R observations in Loiano
  63. GRB041006: VLT observations of the afterglow and host galaxy
  64. GRB041006: Optical observations and Potential host galaxy
  65. GRB041006, BVRcIc field calibration
  66. GRB 040924: VLT spectroscopy
  67. GRB 041006: SARA afterglow observations
  68. Search for SN light in XRF 040912 with MEGACAM
  69. GRB 040916: Afterglow Color at Early Times
  70. GRB 041006 Optical afterglow observations
  71. IBAS GRB Alert # 2010
  72. GRB 041006: BR observations with VATT
  73. GRB 041006: Redshift confirmed
  74. GRB041006: Liverpool Telescope optical observations
  75. GRB 041006: Colour measurement
  76. GRB041006: break in the light curve
  77. GRB 041006: Radio Observations
  78. GRB041006, further submilllimetre observations
  79. GRB 041006 : optical follow-up observation at Lulin Observatory
  80. GRB 041006 : Optical follow-up observation at TAROT
  81. GRB041006: Optical photometry and spectroscopy at TNG
  82. GRB 041006: presice astrometry
  83. GRB041006 (= H3570): Chandra Observations In Progress
  84. GRB 041006 : optical observation at Bisei
  85. GRB041006 (=HETE3570): optical observations
  86. ROTSE-IIIa Observations of GRB 041006
  87. GRB041006, submillimetre observations
  88. GRB041006: MASTER optical observations
  89. GRB 041006: Optical decay
  90. GRB 041006 (=H3570): An X-Ray Rich GRB Localized in Real Time by HETE
  91. GRB 041006 : Optical follow-up observation at KISO
  92. GRB 041006: Finding chart
  93. GRB 041006: Optical afterglow candidate
  94. XRF 020903: Observations of the Host Galaxy (authors)
  95. GRB 040924: Second Epoch WSRT Radio Observations
  96. radio observations, GRB 040924
  97. IBAS Alert 1991. Not a real GRB
  98. GRB040929,optical observation
  99. GRB040924,optical observation
  100. GRB040924, RTT150 optical observation

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