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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"

32548 results found.

  1. GRB 020322: Optical Observations
  2. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  3. GRB 020321: Optical observations
  4. GRB020317 BVRI field photometry
  5. GRB011211 revised BVRI field photometry
  6. GRB020305 BVRI field photometry
  7. GRB020322 BVRI field photometry
  8. GRB 020322 optical observations
  9. GRB020322: Candidate Optical Afterglow
  10. GRB 020322 optical observation
  11. GRB 020322: Optical Sources and Improved Astrometry
  12. GRB020322, optical observations
  13. GRB 020322: Optical candidate
  14. XMM-Newton observation of GRB020322
  15. GRB020322: Optical Observations
  16. GRB 020321: Optical observations
  17. GRB 011121: Fourth Epoch of HST Imaging
  18. GRB020317: optical observations
  19. GRB020321 optical observations
  20. GRB020305: NIR observations
  21. GRB 020317 : KISO Optical Observations
  22. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  23. GRB 020305: Optical Observations
  24. GRB020317, optical observations
  25. GRB 011121: Third HST Epoch
  26. GRB020305: Properties of the Candidate Optical Afterglow
  27. GRB 011121: HST Observations reveal an intermediate-time multicolor
  28. GRB011121, possible supernova association
  29. GRB011130 (XRF011130) Second Epoch Chandra Observations
  30. GRB020305: Subaru Optical Observations
  31. GRB 020305: Optical observations
  32. XRF/GRB 011030 Images
  33. XRF/GRB 011030: Detection of the Probable Host Galaxy
  34. GRB 020305: Candidate optical afterglow
  35. Type Ic SN2002bl (SN/GRB?) Radio Observations
  36. GRB020305 (=H1939): Localization of a GRB by HETE
  37. HST Imaging of the afterglow and host of GRB 011121
  38. GRB 010921: HST Observations
  39. GRB020127: Further VLA Observations of Possible Counterparts
  40. IPN detection of further SGR1900+14 activity
  41. SGR1900+14 activity
  42. GRB020124 BVRI field photometry
  43. GRB020127: Palomar and VLA Observations of Possible Counterparts
  44. GRB020127, WSRT radio observations
  45. GRB020127 Optical Observations
  46. SN2002ap (SN/GRB?) UBVRI Field Photometry
  47. GRB020127: Chandra Observations and Prospective Counterparts
  48. pre-SN2002ap (SN/GRB?) imaging of M74
  49. Type Ib/c SN2002ap (SN/GRB?)
  50. GRB020127: Optical observations
  51. GRB 020127, I-band observations starting 3.14-hr after the event
  52. IPN triangulation of GRB020127 (=H1902)
  53. GRB020127 Optical Observations -- Erratum to GCN 1230
  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. GRB 020124: Optical afterglow
  63. GRB020124(=H1896): Localization of a Long GRB by HETE
  64. GRB optical counterpart candidate in GCN 1217 is M dwarf
  65. GRB011212, Optical Observations
  66. GRB011211: BeppoSAX/GRBM data
  67. Optical polarization observations for GRB011211
  68. Color indices of the afterglow of GRB011211
  69. GRB011212: Optical observations at Gunma
  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. GRB011212: Optical observations
  74. GRB 011212: optical observation at Asiago
  75. GRB 011211: Evidence for an Optical Break
  76. GRB 011211: TNG Spectroscopic Observations
  77. optical follow-up of GRB(XRF) 011211
  78. GRB 011212: optical observation at Oslo (relayed)
  79. GRB 011211: Optical Spectroscopy
  80. GRB 011211, Optical Observations
  81. GRB011212, BVRI field photometry
  82. GRB011211, BVRI field photometry
  83. GRB011212: Optical observations
  84. GRB 011211: BVRi-band photometry
  85. Fading of the optical source associated of XRF 011211
  86. XMM-Newton observation of GRB011211
  87. GRB 011211 Optical Observations: Likely Afterglow
  88. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  89. GRB 011130: Optical Observations of Chandra Sources
  90. GRB 011130: Optical Observations of Chandra sources
  91. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  92. GRB 011130: Magellan spectroscopy
  93. GRB011130, optical observations
  94. GRB011130, optical observations
  95. GRB011130 (=XRF011130): Second Revised Localization by HETE
  96. GRB 011130 I-band Observation
  97. GRB011130 (XRF011130) optical observations
  98. GRB011130 (XRF011130) SDSS PT i-band observations
  99. XRF011130: Infrared Observations
  100. GRB011130, Radio Observations

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