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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"

35994 results found.

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

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