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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"
  1. GRB020322, optical observations
  2. GRB 020322: Optical candidate
  3. XMM-Newton observation of GRB020322
  4. GRB020322: Optical Observations
  5. GRB020322: BeppoSAX/NFI Observations
  6. Bepposax GRB020322 The second springtime BSAX GRB
  7. GRB 020321: Optical observations
  8. GRB 011121: Fourth Epoch of HST Imaging
  9. GRB020317: optical observations
  10. GRB020321 optical observations
  11. GRB020321: BeppoSAX/NFI Observations
  12. GRB020321: a faint BeppoSAX detection
  13. GRB020305: NIR observations
  14. GRB 020317 : KISO Optical Observations
  15. BeppoSAX ALERT: GRB020321, the "Springtime Burst"
  16. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  17. GRB 020305: Optical Observations
  18. GRB020317, optical observations
  19. GRB 020317: Optical observations
  20. GRB 011121: Third HST Epoch
  21. GRB020305: Properties of the Candidate Optical Afterglow
  22. GRB 011121: HST Observations reveal an intermediate-time multicolor
  23. GRB011121, possible supernova association
  24. GRB011130 (XRF011130) Second Epoch Chandra Observations
  25. GRB020305: Subaru Optical Observations
  26. GRB 020305: Optical observations
  27. XRF/GRB 011030 Images
  28. XRF/GRB 011030: Detection of the Probable Host Galaxy
  29. GRB 020305: Candidate optical afterglow
  30. Type Ic SN2002bl (SN/GRB?) Radio Observations
  31. GRB020305, optical observations
  32. GRB020305: Optical Observations
  33. IPN triangulation of GRB020305 (HETE 1939)
  34. GRB020305 (=H1939): Localization of a GRB by HETE
  35. GRB 020305: Optical observations
  36. HST Imaging of the afterglow and host of GRB 011121
  37. GRB 010921: HST Observations
  38. IPN detection and localization of Cygnus X-1 flares
  39. GRB020127: Further VLA Observations of Possible Counterparts
  40. RXTE Observations of SGR 1900+14
  41. IPN detection of further SGR1900+14 activity
  42. SGR1900+14 activity
  43. IPN/HETE Detection of Bursts from SGR1900+14
  44. IPN Upper Limits to a GRB Associated With SN2002ap
  45. GRB020124 BVRI field photometry
  46. GRB020127: Palomar and VLA Observations of Possible Counterparts
  47. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  48. SN2002ap (SN/GRB?) Echelle spectra
  49. SN2002ap (SN/GRB?) optical spectrographic observations
  50. GRB020127, WSRT radio observations
  51. GRB020127 Optical Observations
  52. SN 2002ap (SN/GRB?)
  53. SN 2002ap in M74
  54. SN2002ap (SN/GRB?) UBVRI Field Photometry
  55. GRB020127: Chandra Observations and Prospective Counterparts
  56. pre-SN2002ap (SN/GRB?) imaging of M74
  57. SN 2002ap (hypernova / GRB ??): special list on VSNET
  58. Type Ib/c SN2002ap (SN/GRB?)
  59. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  60. GRB020124, optical observations
  61. GRB020127: Optical observations
  62. GRB 020127, I-band observations starting 3.14-hr after the event
  63. IPN detection of further activity from SGR1806-20
  64. IPN triangulation of GRB020127 (=H1902)
  65. GRB020127 Optical Observations -- Erratum to GCN 1230
  66. GRB010921 Optical Observations
  67. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  68. GRB020124: Optical observations
  69. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  70. GRB020124: Optical observations
  71. GRB 020124: Optical observations
  72. GRB 020124 Optical Observations
  73. IPN triangulation of GRB020124 (HETE 1896)
  74. IPN observations of SGR1806-20
  75. GRB 020124: Optical afterglow
  76. GRB020124(=H1896): Localization of a Long GRB by HETE
  77. HETE 1896: Optical observations
  78. GRB optical counterpart candidate in GCN 1217 is M dwarf
  79. Possible optical counterpart to a GRB
  80. GRB011212, Optical Observations
  81. GRB011211: BeppoSAX/GRBM data
  82. Optical polarization observations for GRB011211
  83. GRB 011211: Detection of the Probable Host Galaxy
  84. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  85. Color indices of the afterglow of GRB011211
  86. GRB011212: Optical observations at Gunma
  87. GRB 011211, spectrum and optical photometry
  88. GRB 011130: Optical Observations of X-ray and Radio Sources
  89. GRB 011130, Radio/X-ray Comparison
  90. GRB011212: Optical observations
  91. GRB 011212: optical observation at Asiago
  92. GRB 011211: Evidence for an Optical Break
  93. GRB 011211: TNG Spectroscopic Observations
  94. optical follow-up of GRB(XRF) 011211
  95. GRB 011212: optical observation at Oslo (relayed)
  96. GRB 011211: Optical Spectroscopy
  97. GRB 011211, Optical Observations
  98. GRB011212, BVRI field photometry
  99. GRB011211, BVRI field photometry
  100. GRB011212: Optical observations

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