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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

36146 results found.

  1. GRB011212: Optical Observations
  2. GRB 020331: NIR Observations
  3. GRB 020331: NIR Observations
  4. GRB020331 NIR observation at KPNO (re-submission)
  5. GRB02033 NIR observation at KPNO
  6. GRB020331 field photometry
  7. GRB 020331 Optical Observations
  8. GRB 020331, NIR observations
  9. GRB 020331: Optical observations
  10. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  11. GRB 020321: Infrared observations
  12. GRB 020322: BeppoSAX observations of the X-ray afterglow
  13. SN 2002ap - peak brightness date (SN/GRB?)
  14. GRB 020322, Radio observations
  15. Near-Infrared Observations of GRB020322 at TIRGO
  16. GRB 020321, Radio Observations
  17. GRB 020322: Optical Observations
  18. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  19. GRB 020321: Optical observations
  20. GRB020317 BVRI field photometry
  21. GRB011211 revised BVRI field photometry
  22. GRB020305 BVRI field photometry
  23. GRB020322 BVRI field photometry
  24. GRB 020322 optical observations
  25. GRB 020322 optical observation
  26. GRB020317 : Near IR Observations from Mt Abu Observatory
  27. GRB 020322: Optical Sources and Improved Astrometry
  28. GRB020322, optical observations
  29. GRB 020322: Optical candidate
  30. GRB020322: BeppoSAX/NFI Observations
  31. Bepposax GRB020322 The second springtime BSAX GRB
  32. GRB 020321: Optical observations
  33. GRB 011121: Fourth Epoch of HST Imaging
  34. GRB020317: optical observations
  35. GRB020321 optical observations
  36. GRB020321: BeppoSAX/NFI Observations
  37. GRB020321: a faint BeppoSAX detection
  38. GRB 020317 : KISO Optical Observations
  39. BeppoSAX ALERT: GRB020321, the "Springtime Burst"
  40. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  41. GRB 020305: Optical Observations
  42. GRB020317, optical observations
  43. GRB 020317: Optical observations
  44. GRB 011121: Third HST Epoch
  45. GRB020305: Properties of the Candidate Optical Afterglow
  46. GRB 011121: HST Observations reveal an intermediate-time multicolor
  47. GRB011121, possible supernova association
  48. GRB011130 (XRF011130) Second Epoch Chandra Observations
  49. GRB020305: Subaru Optical Observations
  50. GRB 020305: Optical observations
  51. XRF/GRB 011030 Images
  52. XRF/GRB 011030: Detection of the Probable Host Galaxy
  53. GRB 020305: Candidate optical afterglow
  54. Type Ic SN2002bl (SN/GRB?) Radio Observations
  55. GRB020305: Optical Observations
  56. IPN triangulation of GRB020305 (HETE 1939)
  57. GRB020305 (=H1939): Localization of a GRB by HETE
  58. GRB 020305: Optical observations
  59. HST Imaging of the afterglow and host of GRB 011121
  60. GRB 010921: HST Observations
  61. IPN detection and localization of Cygnus X-1 flares
  62. GRB020127: Further VLA Observations of Possible Counterparts
  63. IPN detection of further SGR1900+14 activity
  64. SGR1900+14 activity
  65. IPN/HETE Detection of Bursts from SGR1900+14
  66. IPN Upper Limits to a GRB Associated With SN2002ap
  67. GRB020124 BVRI field photometry
  68. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  69. SN2002ap (SN/GRB?) Echelle spectra
  70. SN2002ap (SN/GRB?) optical spectrographic observations
  71. GRB020127 Optical Observations
  72. SN 2002ap (SN/GRB?)
  73. SN2002ap (SN/GRB?) UBVRI Field Photometry
  74. GRB020127: Chandra Observations and Prospective Counterparts
  75. pre-SN2002ap (SN/GRB?) imaging of M74
  76. SN 2002ap (hypernova / GRB ??): special list on VSNET
  77. Type Ib/c SN2002ap (SN/GRB?)
  78. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  79. GRB020124, optical observations
  80. GRB020127: Optical observations
  81. GRB 020127, I-band observations starting 3.14-hr after the event
  82. IPN detection of further activity from SGR1806-20
  83. IPN triangulation of GRB020127 (=H1902)
  84. GRB010921 Optical Observations
  85. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  86. GRB020124: Optical observations
  87. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  88. GRB020124: Optical observations
  89. GRB 020124: Optical observations
  90. GRB 020124 Optical Observations
  91. IPN triangulation of GRB020124 (HETE 1896)
  92. IPN observations of SGR1806-20
  93. GRB 020124: Optical afterglow
  94. GRB020124(=H1896): Localization of a Long GRB by HETE
  95. GRB optical counterpart candidate in GCN 1217 is M dwarf
  96. Possible optical counterpart to a GRB
  97. GRB011212, Optical Observations
  98. GRB 011211: Detection of the Probable Host Galaxy
  99. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  100. GRB 011211, spectrum and optical photometry

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