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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"

36193 results found.

  1. Type Ic SN2002bl (SN/GRB?) Radio Observations
  2. GRB020305: Optical Observations
  3. IPN triangulation of GRB020305 (HETE 1939)
  4. GRB020305 (=H1939): Localization of a GRB by HETE
  5. GRB 020305: Optical observations
  6. HST Imaging of the afterglow and host of GRB 011121
  7. GRB 010921: HST Observations
  8. IPN detection and localization of Cygnus X-1 flares
  9. GRB020127: Further VLA Observations of Possible Counterparts
  10. IPN detection of further SGR1900+14 activity
  11. SGR1900+14 activity
  12. IPN/HETE Detection of Bursts from SGR1900+14
  13. IPN Upper Limits to a GRB Associated With SN2002ap
  14. GRB020124 BVRI field photometry
  15. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  16. SN2002ap (SN/GRB?) Echelle spectra
  17. SN2002ap (SN/GRB?) optical spectrographic observations
  18. GRB020127 Optical Observations
  19. SN 2002ap (SN/GRB?)
  20. SN2002ap (SN/GRB?) UBVRI Field Photometry
  21. GRB020127: Chandra Observations and Prospective Counterparts
  22. pre-SN2002ap (SN/GRB?) imaging of M74
  23. SN 2002ap (hypernova / GRB ??): special list on VSNET
  24. Type Ib/c SN2002ap (SN/GRB?)
  25. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  26. GRB020124, optical observations
  27. GRB020127: Optical observations
  28. GRB 020127, I-band observations starting 3.14-hr after the event
  29. IPN detection of further activity from SGR1806-20
  30. IPN triangulation of GRB020127 (=H1902)
  31. GRB010921 Optical Observations
  32. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  33. GRB020124: Optical observations
  34. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  35. GRB020124: Optical observations
  36. GRB 020124: Optical observations
  37. GRB 020124 Optical Observations
  38. IPN triangulation of GRB020124 (HETE 1896)
  39. IPN observations of SGR1806-20
  40. GRB 020124: Optical afterglow
  41. GRB020124(=H1896): Localization of a Long GRB by HETE
  42. GRB optical counterpart candidate in GCN 1217 is M dwarf
  43. Possible optical counterpart to a GRB
  44. GRB011212, Optical Observations
  45. GRB 011211: Detection of the Probable Host Galaxy
  46. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  47. GRB 011211, spectrum and optical photometry
  48. GRB 011130: Optical Observations of X-ray and Radio Sources
  49. GRB 011130, Radio/X-ray Comparison
  50. GRB 011212: optical observation at Asiago
  51. GRB 011211: Evidence for an Optical Break
  52. GRB 011211: TNG Spectroscopic Observations
  53. optical follow-up of GRB(XRF) 011211
  54. GRB 011212: optical observation at Oslo (relayed)
  55. GRB 011211: Optical Spectroscopy
  56. GRB 011211, Optical Observations
  57. GRB011212, BVRI field photometry
  58. GRB011211, BVRI field photometry
  59. GRB011212: Optical observations
  60. GRB 011211: BVRi-band photometry
  61. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  62. Fading of the optical source associated of XRF 011211
  63. GRB 011211 Optical Observations: Likely Afterglow
  64. BeppoSAX Alert: GRB011211(=XRF011211)
  65. GRB 011130: Optical Observations of Chandra Sources
  66. GRB 011130: Optical Observations of Chandra sources
  67. GRB 011130: Magellan spectroscopy
  68. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  69. GRB011130, optical observations
  70. GRB 011130, K band observations
  71. GRB011130, optical observations
  72. GRB 011130 I-band Observation
  73. GRB011130 (XRF011130) optical observations
  74. GRB011130 (XRF011130) SDSS PT i-band observations
  75. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  76. XRF011130: NEAT Optical Observations
  77. GRB011130 (=XRF011130): Revised Localization of an X-ray
  78. GRB001109, Radio Monitoring
  79. GRB 011121: Errata URL
  80. GRB 011121
  81. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  82. GRB 011121: J-band observations
  83. GRB 011121: NIR observations, host galaxy?
  84. GRB 011121: HST Scheduled
  85. GRB011121: fainter still
  86. Correction: GCN1157 (GRB 011121)
  87. GRB 011121: Radio Observations
  88. GRB 011121 J-Band Astrometry
  89. GRB011121: continued decay
  90. GRB 011121: Detection of Bright IR Counterpart
  91. GRB011121: possible redshift, continued decay
  92. IPN triangulation of GRB011121
  93. BEPPOSAX GRB011121
  94. GRB 011030: TNG K-band observation
  95. XRF011030: Chandra Observations
  96. GRB 011030: K-band observations
  97. GRB 011030 R band observations
  98. GRB 011030 I-band Observation
  99. The X-ray Flash 011030 ('GRB 011030')
  100. Non-triggered burst 011030 ("GRB 011030")

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