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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"

28230 results found.

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

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