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

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