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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"

36314 results found.

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

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