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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').
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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"

42564 results found.

  1. RXTE Observations of SGR 1900+14
  2. IPN detection of further SGR1900+14 activity
  3. SGR1900+14 activity
  4. IPN/HETE Detection of Bursts from SGR1900+14
  5. IPN Upper Limits to a GRB Associated With SN2002ap
  6. GRB020124 BVRI field photometry
  7. GRB020127: Palomar and VLA Observations of Possible Counterparts
  8. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  9. SN2002ap (SN/GRB?) Echelle spectra
  10. SN2002ap (SN/GRB?) optical spectrographic observations
  11. GRB020127, WSRT radio observations
  12. GRB020127 Optical Observations
  13. SN 2002ap (SN/GRB?)
  14. SN 2002ap in M74
  15. SN2002ap (SN/GRB?) UBVRI Field Photometry
  16. GRB020127: Chandra Observations and Prospective Counterparts
  17. pre-SN2002ap (SN/GRB?) imaging of M74
  18. SN 2002ap (hypernova / GRB ??): special list on VSNET
  19. Type Ib/c SN2002ap (SN/GRB?)
  20. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  21. GRB 020127, I-band observations starting 3.14-hr after the event
  22. IPN triangulation of GRB020127 (=H1902)
  23. GRB010921 Optical Observations
  24. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  25. GRB020124: Optical observations
  26. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  27. GRB020124: Optical observations
  28. GRB 020124: Optical observations
  29. GRB 020124 Optical Observations
  30. IPN triangulation of GRB020124 (HETE 1896)
  31. IPN observations of SGR1806-20
  32. GRB 020124: Optical afterglow
  33. GRB020124(=H1896): Localization of a Long GRB by HETE
  34. HETE 1896: Optical observations
  35. GRB optical counterpart candidate in GCN 1217 is M dwarf
  36. Possible optical counterpart to a GRB
  37. GRB011212, Optical Observations
  38. GRB011211: BeppoSAX/GRBM data
  39. Optical polarization observations for GRB011211
  40. GRB 011211: Detection of the Probable Host Galaxy
  41. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  42. Color indices of the afterglow of GRB011211
  43. GRB011212: Optical observations at Gunma
  44. GRB 011211, spectrum and optical photometry
  45. GRB 011130, Radio/X-ray Comparison
  46. GRB011212: Optical observations
  47. GRB 011212: optical observation at Asiago
  48. GRB 011211: Evidence for an Optical Break
  49. GRB 011211: TNG Spectroscopic Observations
  50. GRB 011212: optical observation at Oslo (relayed)
  51. GRB 011211: Optical Spectroscopy
  52. GRB 011211, Optical Observations
  53. GRB011212, BVRI field photometry
  54. GRB011211, BVRI field photometry
  55. GRB 011211: BVRi-band photometry
  56. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  57. Fading of the optical source associated of XRF 011211
  58. XMM-Newton observation of GRB011211
  59. GRB 011211 Optical Observations: Likely Afterglow
  60. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  61. GRB 011130: Optical Observations of Chandra Sources
  62. GRB011130 (XRF011130) Chandra Observations
  63. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  64. GRB 011130: Magellan spectroscopy
  65. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  66. GRB011130, optical observations
  67. GRB 011130, K band observations
  68. GRB011130, optical observations
  69. GRB011130 (=XRF011130): Second Revised Localization by HETE
  70. GRB 011130 I-band Observation
  71. GRB011130 (XRF011130) optical observations
  72. GRB011130 (XRF011130) SDSS PT i-band observations
  73. XRF011130: Infrared Observations
  74. GRB011130, Radio Observations
  75. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  76. GRB011130 (=XRF011130), Optical Observations
  77. GRB011130 (=XRF011130): Revised Localization of an X-ray
  78. GRB001109, Radio Monitoring
  79. GRB 011121
  80. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  81. GRB 011121: J-band observations
  82. GRB 011121: NIR observations, host galaxy?
  83. GRB010921 - Milagro GeV/TeV Observations
  84. GRB 011121: HST Scheduled
  85. GRB011121: fainter still
  86. GRB011121: UBRI Observations
  87. GRB011121
  88. GRB 011121: Radio Observations
  89. GRB 011121 J-Band Astrometry
  90. GRB011121: continued decay
  91. GRB 011121: Detection of Bright IR Counterpart
  92. GRB011121: possible redshift, continued decay
  93. GRB011121: fading behavior
  94. GRB011121: possible optical counterpart
  95. GRB011121: BeppoSAX-WFC refined positions
  96. IPN triangulation of GRB011121
  97. BEPPOSAX GRB011121
  98. GRB 011030: TNG K-band observation
  99. XRF011030: J and K band observations
  100. XRF011030: Chandra Observations

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