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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"

36313 results found.

  1. GRB020317: optical observations
  2. GRB020321 optical observations
  3. GRB020321: BeppoSAX/NFI Observations
  4. GRB020321: a faint BeppoSAX detection
  5. GRB 020317 : KISO Optical Observations
  6. BeppoSAX ALERT: GRB020321, the "Springtime Burst"
  7. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  8. GRB 020305: Optical Observations
  9. GRB020317, optical observations
  10. GRB 020317: Optical observations
  11. GRB 011121: Third HST Epoch
  12. GRB020305: Properties of the Candidate Optical Afterglow
  13. GRB 011121: HST Observations reveal an intermediate-time multicolor
  14. GRB011121, possible supernova association
  15. GRB011130 (XRF011130) Second Epoch Chandra Observations
  16. GRB020305: Subaru Optical Observations
  17. GRB 020305: Optical observations
  18. XRF/GRB 011030 Images
  19. XRF/GRB 011030: Detection of the Probable Host Galaxy
  20. GRB 020305: Candidate optical afterglow
  21. Type Ic SN2002bl (SN/GRB?) Radio Observations
  22. GRB020305: Optical Observations
  23. IPN triangulation of GRB020305 (HETE 1939)
  24. GRB020305 (=H1939): Localization of a GRB by HETE
  25. GRB 020305: Optical observations
  26. HST Imaging of the afterglow and host of GRB 011121
  27. GRB 010921: HST Observations
  28. IPN detection and localization of Cygnus X-1 flares
  29. GRB020127: Further VLA Observations of Possible Counterparts
  30. IPN detection of further SGR1900+14 activity
  31. SGR1900+14 activity
  32. IPN/HETE Detection of Bursts from SGR1900+14
  33. IPN Upper Limits to a GRB Associated With SN2002ap
  34. GRB020124 BVRI field photometry
  35. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  36. SN2002ap (SN/GRB?) Echelle spectra
  37. SN2002ap (SN/GRB?) optical spectrographic observations
  38. GRB020127 Optical Observations
  39. SN 2002ap (SN/GRB?)
  40. SN2002ap (SN/GRB?) UBVRI Field Photometry
  41. GRB020127: Chandra Observations and Prospective Counterparts
  42. pre-SN2002ap (SN/GRB?) imaging of M74
  43. SN 2002ap (hypernova / GRB ??): special list on VSNET
  44. Type Ib/c SN2002ap (SN/GRB?)
  45. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  46. GRB020124, optical observations
  47. GRB020127: Optical observations
  48. GRB 020127, I-band observations starting 3.14-hr after the event
  49. IPN detection of further activity from SGR1806-20
  50. IPN triangulation of GRB020127 (=H1902)
  51. GRB010921 Optical Observations
  52. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  53. GRB020124: Optical observations
  54. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  55. GRB020124: Optical observations
  56. GRB 020124: Optical observations
  57. GRB 020124 Optical Observations
  58. IPN triangulation of GRB020124 (HETE 1896)
  59. IPN observations of SGR1806-20
  60. GRB 020124: Optical afterglow
  61. GRB020124(=H1896): Localization of a Long GRB by HETE
  62. GRB optical counterpart candidate in GCN 1217 is M dwarf
  63. Possible optical counterpart to a GRB
  64. GRB011212, Optical Observations
  65. GRB 011211: Detection of the Probable Host Galaxy
  66. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  67. GRB 011211, spectrum and optical photometry
  68. GRB 011130: Optical Observations of X-ray and Radio Sources
  69. GRB 011130, Radio/X-ray Comparison
  70. GRB 011212: optical observation at Asiago
  71. GRB 011211: Evidence for an Optical Break
  72. GRB 011211: TNG Spectroscopic Observations
  73. optical follow-up of GRB(XRF) 011211
  74. GRB 011212: optical observation at Oslo (relayed)
  75. GRB 011211: Optical Spectroscopy
  76. GRB 011211, Optical Observations
  77. GRB011212, BVRI field photometry
  78. GRB011211, BVRI field photometry
  79. GRB011212: Optical observations
  80. GRB 011211: BVRi-band photometry
  81. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  82. Fading of the optical source associated of XRF 011211
  83. GRB 011211 Optical Observations: Likely Afterglow
  84. BeppoSAX Alert: GRB011211(=XRF011211)
  85. GRB 011130: Optical Observations of Chandra Sources
  86. GRB 011130: Optical Observations of Chandra sources
  87. GRB 011130: Magellan spectroscopy
  88. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  89. GRB011130, optical observations
  90. GRB 011130, K band observations
  91. GRB011130, optical observations
  92. GRB 011130 I-band Observation
  93. GRB011130 (XRF011130) optical observations
  94. GRB011130 (XRF011130) SDSS PT i-band observations
  95. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  96. XRF011130: NEAT Optical Observations
  97. GRB011130 (=XRF011130): Revised Localization of an X-ray
  98. GRB001109, Radio Monitoring
  99. GRB 011121: Errata URL
  100. GRB 011121

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