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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"

24605 results found.

  1. GRB020124 optical observations with RIBOTS/RIMOTS
  2. GRB 020321: Candidate X-ray Counterparts
  3. GRB020406(?), optical observations
  4. GRB 020405: Decay index
  5. Short RXTE/ASM transient 020406; may be a GRB
  6. GRB020405, Radio Observations
  7. GRB 020405, U-band observations
  8. GRB011212: Optical Observations
  9. GRB 020331: NIR Observations
  10. GRB020331 NIR observation at KPNO (re-submission)
  11. GRB02033 NIR observation at KPNO
  12. GRB020331 field photometry
  13. GRB 020331, NIR observations
  14. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  15. GRB 020322: BeppoSAX observations of the X-ray afterglow
  16. GRB011211: HST Observations of Optical Afterglow and Host Galaxy
  17. Near-Infrared Observations of GRB020322 at TIRGO
  18. GRB 020321, Radio Observations
  19. GRB 020322: Optical Observations
  20. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  21. GRB 020321: Optical observations
  22. GRB020317 BVRI field photometry
  23. GRB011211 revised BVRI field photometry
  24. GRB020305 BVRI field photometry
  25. GRB020322 BVRI field photometry
  26. GRB 020322: Optical Sources and Improved Astrometry
  27. GRB020317: optical observations
  28. GRB020321 optical observations
  29. GRB020321: a faint BeppoSAX detection
  30. GRB 020317 : KISO Optical Observations
  31. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  32. GRB 020305: Optical Observations
  33. GRB020317, optical observations
  34. GRB 020317: Optical observations
  35. GRB 011121: Third HST Epoch
  36. GRB020305: Properties of the Candidate Optical Afterglow
  37. GRB 011121: HST Observations reveal an intermediate-time multicolor
  38. GRB011130 (XRF011130) Second Epoch Chandra Observations
  39. GRB020305: Subaru Optical Observations
  40. XRF/GRB 011030: Detection of the Probable Host Galaxy
  41. GRB 020305: Candidate optical afterglow
  42. GRB020305, optical observations
  43. IPN triangulation of GRB020305 (HETE 1939)
  44. GRB020305 (=H1939): Localization of a GRB by HETE
  45. HST Imaging of the afterglow and host of GRB 011121
  46. IPN detection and localization of Cygnus X-1 flares
  47. SGR1900+14 activity
  48. IPN Upper Limits to a GRB Associated With SN2002ap
  49. GRB020124 BVRI field photometry
  50. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  51. SN2002ap (SN/GRB?) Echelle spectra
  52. GRB020127 Optical Observations
  53. SN 2002ap in M74
  54. SN2002ap (SN/GRB?) UBVRI Field Photometry
  55. GRB020127: Chandra Observations and Prospective Counterparts
  56. pre-SN2002ap (SN/GRB?) imaging of M74
  57. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  58. GRB020124, optical observations
  59. GRB 020127, I-band observations starting 3.14-hr after the event
  60. GRB010921 Optical Observations
  61. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  62. GRB020124: Optical observations
  63. GRB 020124: Optical observations
  64. GRB 020124: Optical afterglow
  65. GRB020124(=H1896): Localization of a Long GRB by HETE
  66. Possible optical counterpart to a GRB
  67. GRB011212, Optical Observations
  68. Optical polarization observations for GRB011211
  69. GRB 011211: Detection of the Probable Host Galaxy
  70. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  71. GRB 011130: Optical Observations of X-ray and Radio Sources
  72. GRB 011212: optical observation at Asiago
  73. GRB 011211: Evidence for an Optical Break
  74. GRB 011211: TNG Spectroscopic Observations
  75. optical follow-up of GRB(XRF) 011211
  76. GRB 011212: optical observation at Oslo (relayed)
  77. GRB 011211, Optical Observations
  78. GRB011212, BVRI field photometry
  79. GRB011211, BVRI field photometry
  80. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  81. Fading of the optical source associated of XRF 011211
  82. GRB 011211 Optical Observations: Likely Afterglow
  83. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  84. GRB011130 (XRF011130) Chandra Observations
  85. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  86. GRB 011130, K band observations
  87. GRB011130, optical observations
  88. GRB011130 (=XRF011130): Second Revised Localization by HETE
  89. GRB011130 (XRF011130) SDSS PT i-band observations
  90. XRF011130: Infrared Observations
  91. GRB 011121
  92. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  93. GRB 011121: J-band observations
  94. GRB 011121: NIR observations, host galaxy?
  95. GRB011121: UBRI Observations
  96. GRB 011121 J-Band Astrometry
  97. GRB 011121: Detection of Bright IR Counterpart
  98. GRB011121: possible redshift, continued decay
  99. GRB 011030: TNG K-band observation
  100. XRF011030: J and K band observations

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