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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"

24997 results found.

  1. GRB 020331: NIR Observations
  2. GRB020331 NIR observation at KPNO (re-submission)
  3. GRB02033 NIR observation at KPNO
  4. GRB020331 field photometry
  5. GRB 020331, NIR observations
  6. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  7. GRB 020322: BeppoSAX observations of the X-ray afterglow
  8. GRB011211: HST Observations of Optical Afterglow and Host Galaxy
  9. Near-Infrared Observations of GRB020322 at TIRGO
  10. GRB 020321, Radio Observations
  11. GRB 020322: Optical Observations
  12. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  13. GRB 020321: Optical observations
  14. GRB020317 BVRI field photometry
  15. GRB011211 revised BVRI field photometry
  16. GRB020305 BVRI field photometry
  17. GRB020322 BVRI field photometry
  18. GRB 020322: Optical Sources and Improved Astrometry
  19. GRB020317: optical observations
  20. GRB020321 optical observations
  21. GRB020321: a faint BeppoSAX detection
  22. GRB 020317 : KISO Optical Observations
  23. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  24. GRB 020305: Optical Observations
  25. GRB020317, optical observations
  26. GRB 020317: Optical observations
  27. GRB 011121: Third HST Epoch
  28. GRB020305: Properties of the Candidate Optical Afterglow
  29. GRB 011121: HST Observations reveal an intermediate-time multicolor
  30. GRB011130 (XRF011130) Second Epoch Chandra Observations
  31. GRB020305: Subaru Optical Observations
  32. XRF/GRB 011030: Detection of the Probable Host Galaxy
  33. GRB 020305: Candidate optical afterglow
  34. GRB020305, optical observations
  35. IPN triangulation of GRB020305 (HETE 1939)
  36. GRB020305 (=H1939): Localization of a GRB by HETE
  37. HST Imaging of the afterglow and host of GRB 011121
  38. IPN detection and localization of Cygnus X-1 flares
  39. SGR1900+14 activity
  40. IPN Upper Limits to a GRB Associated With SN2002ap
  41. GRB020124 BVRI field photometry
  42. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  43. SN2002ap (SN/GRB?) Echelle spectra
  44. GRB020127 Optical Observations
  45. SN 2002ap in M74
  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?) Radio Observations
  50. GRB020124, optical observations
  51. GRB 020127, I-band observations starting 3.14-hr after the event
  52. GRB010921 Optical Observations
  53. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  54. GRB020124: Optical observations
  55. GRB 020124: Optical observations
  56. GRB 020124: Optical afterglow
  57. GRB020124(=H1896): Localization of a Long GRB by HETE
  58. Possible optical counterpart to a GRB
  59. GRB011212, Optical Observations
  60. Optical polarization observations for GRB011211
  61. GRB 011211: Detection of the Probable Host Galaxy
  62. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  63. GRB 011130: Optical Observations of X-ray and Radio Sources
  64. GRB 011212: optical observation at Asiago
  65. GRB 011211: Evidence for an Optical Break
  66. GRB 011211: TNG Spectroscopic Observations
  67. optical follow-up of GRB(XRF) 011211
  68. GRB 011212: optical observation at Oslo (relayed)
  69. GRB 011211, Optical Observations
  70. GRB011212, BVRI field photometry
  71. GRB011211, BVRI field photometry
  72. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  73. Fading of the optical source associated of XRF 011211
  74. GRB 011211 Optical Observations: Likely Afterglow
  75. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  76. GRB011130 (XRF011130) Chandra Observations
  77. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  78. GRB 011130, K band observations
  79. GRB011130, optical observations
  80. GRB011130 (=XRF011130): Second Revised Localization by HETE
  81. GRB011130 (XRF011130) SDSS PT i-band observations
  82. XRF011130: Infrared Observations
  83. GRB 011121
  84. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  85. GRB 011121: J-band observations
  86. GRB 011121: NIR observations, host galaxy?
  87. GRB011121: UBRI Observations
  88. GRB 011121 J-Band Astrometry
  89. GRB 011121: Detection of Bright IR Counterpart
  90. GRB011121: possible redshift, continued decay
  91. GRB 011030: TNG K-band observation
  92. XRF011030: J and K band observations
  93. XRF011030: Chandra Observations
  94. GRB011030: Z-band observations
  95. GRB 011030 R band observations
  96. GRB 011030 I-band Observation
  97. The X-ray Flash 011030 ('GRB 011030')
  98. Non-triggered burst 011030 ("GRB 011030")
  99. The Radio Afterglow from the X-ray Rich GRB 011030
  100. GRB 010921: HST Detection of the Afterglow and Host Galaxy

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