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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"

36012 results found.

  1. Bepposax GRB020322 The second springtime BSAX GRB
  2. GRB 020321: Optical observations
  3. GRB 011121: Fourth Epoch of HST Imaging
  4. GRB020317: optical observations
  5. GRB020321 optical observations
  6. GRB020321: BeppoSAX/NFI Observations
  7. GRB020321: a faint BeppoSAX detection
  8. GRB 020317 : KISO Optical Observations
  9. BeppoSAX ALERT: GRB020321, the "Springtime Burst"
  10. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  11. GRB 020305: Optical Observations
  12. GRB020317, optical observations
  13. GRB 020317: Optical observations
  14. GRB 011121: Third HST Epoch
  15. GRB020305: Properties of the Candidate Optical Afterglow
  16. GRB 011121: HST Observations reveal an intermediate-time multicolor
  17. GRB011121, possible supernova association
  18. GRB011130 (XRF011130) Second Epoch Chandra Observations
  19. GRB020305: Subaru Optical Observations
  20. GRB 020305: Optical observations
  21. XRF/GRB 011030 Images
  22. XRF/GRB 011030: Detection of the Probable Host Galaxy
  23. GRB 020305: Candidate optical afterglow
  24. Type Ic SN2002bl (SN/GRB?) Radio Observations
  25. GRB020305: Optical Observations
  26. IPN triangulation of GRB020305 (HETE 1939)
  27. GRB020305 (=H1939): Localization of a GRB by HETE
  28. GRB 020305: Optical observations
  29. HST Imaging of the afterglow and host of GRB 011121
  30. GRB 010921: HST Observations
  31. IPN detection and localization of Cygnus X-1 flares
  32. GRB020127: Further VLA Observations of Possible Counterparts
  33. IPN detection of further SGR1900+14 activity
  34. SGR1900+14 activity
  35. IPN/HETE Detection of Bursts from SGR1900+14
  36. IPN Upper Limits to a GRB Associated With SN2002ap
  37. GRB020124 BVRI field photometry
  38. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  39. SN2002ap (SN/GRB?) Echelle spectra
  40. SN2002ap (SN/GRB?) optical spectrographic observations
  41. GRB020127 Optical Observations
  42. SN 2002ap (SN/GRB?)
  43. SN2002ap (SN/GRB?) UBVRI Field Photometry
  44. GRB020127: Chandra Observations and Prospective Counterparts
  45. pre-SN2002ap (SN/GRB?) imaging of M74
  46. SN 2002ap (hypernova / GRB ??): special list on VSNET
  47. Type Ib/c SN2002ap (SN/GRB?)
  48. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  49. GRB020124, optical observations
  50. GRB020127: Optical observations
  51. GRB 020127, I-band observations starting 3.14-hr after the event
  52. IPN detection of further activity from SGR1806-20
  53. IPN triangulation of GRB020127 (=H1902)
  54. GRB010921 Optical Observations
  55. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  56. GRB020124: Optical observations
  57. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  58. GRB020124: Optical observations
  59. GRB 020124: Optical observations
  60. GRB 020124 Optical Observations
  61. IPN triangulation of GRB020124 (HETE 1896)
  62. IPN observations of SGR1806-20
  63. GRB 020124: Optical afterglow
  64. GRB020124(=H1896): Localization of a Long GRB by HETE
  65. GRB optical counterpart candidate in GCN 1217 is M dwarf
  66. Possible optical counterpart to a GRB
  67. GRB011212, Optical Observations
  68. GRB 011211: Detection of the Probable Host Galaxy
  69. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  70. GRB 011211, spectrum and optical photometry
  71. GRB 011130: Optical Observations of X-ray and Radio Sources
  72. GRB 011130, Radio/X-ray Comparison
  73. GRB 011212: optical observation at Asiago
  74. GRB 011211: Evidence for an Optical Break
  75. GRB 011211: TNG Spectroscopic Observations
  76. optical follow-up of GRB(XRF) 011211
  77. GRB 011212: optical observation at Oslo (relayed)
  78. GRB 011211: Optical Spectroscopy
  79. GRB 011211, Optical Observations
  80. GRB011212, BVRI field photometry
  81. GRB011211, BVRI field photometry
  82. GRB011212: Optical observations
  83. GRB 011211: BVRi-band photometry
  84. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  85. Fading of the optical source associated of XRF 011211
  86. GRB 011211 Optical Observations: Likely Afterglow
  87. BeppoSAX Alert: GRB011211(=XRF011211)
  88. GRB 011130: Optical Observations of Chandra Sources
  89. GRB 011130: Optical Observations of Chandra sources
  90. GRB 011130: Magellan spectroscopy
  91. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  92. GRB011130, optical observations
  93. GRB 011130, K band observations
  94. GRB011130, optical observations
  95. GRB 011130 I-band Observation
  96. GRB011130 (XRF011130) optical observations
  97. GRB011130 (XRF011130) SDSS PT i-band observations
  98. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  99. XRF011130: NEAT Optical Observations
  100. GRB011130 (=XRF011130): Revised Localization of an X-ray

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