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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"

28231 results found.

  1. GRB 041223: J-band observations of the afterglow
  2. GRB 041219c: PROMPT Observations
  3. GRB041223: Swift-BAT detection of a bright long burst
  4. GRB 041218: optical observations
  5. GRB 041219 : optical follow-up observations
  6. Deep RAPTOR observations during GRB 041219
  7. GRB 041218 Optical Observations
  8. GRB041219: Continued NIR Observations
  9. GRB 041219 ,optical observation
  10. GRB 041219: Radio Afterglow Detection
  11. GRB 041218 : Radio Observations
  12. GRB 041218: R-band optical observations
  13. GRB041218: optical observations
  14. GRB041219: Confirmed NIR Afterglow
  15. Swift-BAT detection of the bright long burst GRB041219
  16. GRB 041219: Infrared Afterglow Candidate
  17. GRB041219, BVRcIc field calibration
  18. GRB 041219: Infrared Afterglow Candidate
  19. GRB041218, BVRcIc field calibration
  20. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  21. GRB 041219 - A long GRB detected by INTEGRAL
  22. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  23. GRB 041217: PROMPT Observations
  24. GRB 041217: LCO40 Optical Observations and Possible Candidates
  25. GRB 041218 - A long GRB detected by integral
  26. GRB041217: NIR and optical observations with REM
  27. GRB041217: Infrared Observations
  28. GRB041217: The First GRB Located On-Board Swift
  29. GRB041211: Faulkes Telescope continued optical monitoring
  30. Optical Transient in Lynx not a GRB
  31. Optical transient (GRB?) in Lynx
  32. GRB041211: RAPTOR observations
  33. GRB041211: Ashra Prototype optical observation
  34. GRB041211, BVRcIc field calibration
  35. GRB041211,optical observation
  36. GRB 041211: Infrared Observations
  37. GRB 041211: KAIT observations
  38. GRB 041211: Optical follow-up in East Asian region
  39. Triangulation of short GRB 041116 (large error box)
  40. GRB 040924: Afterglow Color
  41. GRB 041006: GETS Optical Afterglow Observation
  42. Summary of the recent bursts from SGR 1806-20
  43. GRB 041006: Optical Observations
  44. GRB041006, late-time optical photometry
  45. GRB041006: RTT150 Optical Observations
  46. HST Observations: XRF 040701 and 040812
  47. Bright bursts from SGR1806-20
  48. GRB 041016: BOOTES-2 simultaneous observation
  49. GRB041006: RTT150 Optical Observations
  50. GRB041016,optical observation
  51. GRB 041016: Optical limits
  52. GRB 041016:Optical limit during first minute
  53. GRB 041015: Optical Observations at Rikubetsu
  54. GRB 041016: Optical limit
  55. GRB 041015 R band observations
  56. GRB040924, BVRcIc field calibration
  57. GRB041015,optical observation
  58. GRB041006: Fading X-ray Afterglow Observed with Chandra
  59. GRB 041015 - A long GRB detected by INTEGRAL
  60. GRB041006: VLT observations of the afterglow and host galaxy
  61. GRB041006: Optical observations and Potential host galaxy
  62. GRB041006, BVRcIc field calibration
  63. GRB 040924: VLT spectroscopy
  64. GRB 041006: SARA afterglow observations
  65. GRB041006, optical observation in CrAO
  66. Search for SN light in XRF 040912 with MEGACAM
  67. GRB 041006: BR observations with VATT
  68. GRB 041006: Redshift confirmed
  69. GRB 041006: Radio Observations
  70. GRB 041006 : optical follow-up observation at Lulin Observatory
  71. GRB041006: Optical photometry and spectroscopy at TNG
  72. GRB 041006: presice astrometry
  73. GRB041006, optical I observation
  74. GRB041006 (=HETE3570): optical observations
  75. ROTSE-IIIa Observations of GRB 041006
  76. GRB041006: MASTER optical observations
  77. GRB041006,optical observation
  78. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  79. GRB041006: Fading of optical afterglow candidate
  80. GRB 041006: Optical afterglow candidate
  81. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  82. XRF 020903: Observations of the Host Galaxy
  83. radio observations, GRB 040924
  84. GRB040929,optical observation
  85. GRB040924,optical observation
  86. GRB040924,optical observation
  87. GRB 040924: detection of possible host galaxy by Subaru
  88. GRB040924: KAIT observations
  89. GRB040924 : Optical candidate observations at Lulin observatory
  90. GRB040924 : Optical candidate observations at Lulin observatory
  91. GRB 040924: Subaru NIR observation
  92. XRF 040912: Radio Observations
  93. XRF 040916: Radio Observations
  94. GRB040912(=H3557): Chandra Candidate X-ray Afterglow
  95. XRF040916: continuing decay of OT
  96. TAROT Observations of GRB 040916 (HETE #3558)
  97. GRB040912(=H3557): Candidate Optical Afterglow
  98. XRF040916, optical observations
  99. XRF 040912, identification of CXO sources
  100. XRF040912, BVRcIc field calibration

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