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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"

24875 results found.

  1. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  2. GRB 020305: Optical Observations
  3. GRB020317, optical observations
  4. GRB 020317: Optical observations
  5. GRB 011121: Third HST Epoch
  6. GRB020305: Properties of the Candidate Optical Afterglow
  7. GRB 011121: HST Observations reveal an intermediate-time multicolor
  8. GRB011130 (XRF011130) Second Epoch Chandra Observations
  9. GRB020305: Subaru Optical Observations
  10. XRF/GRB 011030: Detection of the Probable Host Galaxy
  11. GRB 020305: Candidate optical afterglow
  12. GRB020305, optical observations
  13. IPN triangulation of GRB020305 (HETE 1939)
  14. GRB020305 (=H1939): Localization of a GRB by HETE
  15. HST Imaging of the afterglow and host of GRB 011121
  16. IPN detection and localization of Cygnus X-1 flares
  17. SGR1900+14 activity
  18. IPN Upper Limits to a GRB Associated With SN2002ap
  19. GRB020124 BVRI field photometry
  20. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  21. SN2002ap (SN/GRB?) Echelle spectra
  22. GRB020127 Optical Observations
  23. SN 2002ap in M74
  24. SN2002ap (SN/GRB?) UBVRI Field Photometry
  25. GRB020127: Chandra Observations and Prospective Counterparts
  26. pre-SN2002ap (SN/GRB?) imaging of M74
  27. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  28. GRB020124, optical observations
  29. GRB 020127, I-band observations starting 3.14-hr after the event
  30. GRB010921 Optical Observations
  31. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  32. GRB020124: Optical observations
  33. GRB 020124: Optical observations
  34. GRB 020124: Optical afterglow
  35. GRB020124(=H1896): Localization of a Long GRB by HETE
  36. Possible optical counterpart to a GRB
  37. GRB011212, Optical Observations
  38. Optical polarization observations for GRB011211
  39. GRB 011211: Detection of the Probable Host Galaxy
  40. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  41. GRB 011130: Optical Observations of X-ray and Radio Sources
  42. GRB 011212: optical observation at Asiago
  43. GRB 011211: Evidence for an Optical Break
  44. GRB 011211: TNG Spectroscopic Observations
  45. optical follow-up of GRB(XRF) 011211
  46. GRB 011212: optical observation at Oslo (relayed)
  47. GRB 011211, Optical Observations
  48. GRB011212, BVRI field photometry
  49. GRB011211, BVRI field photometry
  50. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  51. Fading of the optical source associated of XRF 011211
  52. GRB 011211 Optical Observations: Likely Afterglow
  53. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  54. GRB011130 (XRF011130) Chandra Observations
  55. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  56. GRB 011130, K band observations
  57. GRB011130, optical observations
  58. GRB011130 (=XRF011130): Second Revised Localization by HETE
  59. GRB011130 (XRF011130) SDSS PT i-band observations
  60. XRF011130: Infrared Observations
  61. GRB 011121
  62. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  63. GRB 011121: J-band observations
  64. GRB 011121: NIR observations, host galaxy?
  65. GRB011121: UBRI Observations
  66. GRB 011121 J-Band Astrometry
  67. GRB 011121: Detection of Bright IR Counterpart
  68. GRB011121: possible redshift, continued decay
  69. GRB 011030: TNG K-band observation
  70. XRF011030: J and K band observations
  71. XRF011030: Chandra Observations
  72. GRB011030: Z-band observations
  73. GRB 011030 R band observations
  74. GRB 011030 I-band Observation
  75. The X-ray Flash 011030 ('GRB 011030')
  76. Non-triggered burst 011030 ("GRB 011030")
  77. The Radio Afterglow from the X-ray Rich GRB 011030
  78. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  79. GRB 970828: HST Observations of the Host Galaxy
  80. GRB 000131: HST Detection of the Host Galaxy
  81. GRB 970828: HST Observations of the Host Galaxy
  82. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  83. GRB011019: Subaru Optical Observations
  84. GRB 011030 I-band Observations
  85. GRB 011030 K-band Observations
  86. GRB010921, optical observations
  87. GRB011030 - further refinement WFC position
  88. GRB 011030, Radio observations
  89. GRB011030: radio search
  90. GRB 010921: Possible supernova component
  91. GRB010921, optical observation at early time
  92. GRB 010921, I-band observations
  93. GRB011019, optical observations
  94. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  95. GRB 010921: The afterglow of HETE #1761
  96. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  97. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  98. GRB010923 as seen by BeppoSAX GRBM
  99. GRB010928(=H1770): Localization of a Long GRB by HETE
  100. GRB010923(=H1764): A Short Duration GRB Detected by HETE

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