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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"

23409 results found.

  1. XRF 020427
  2. GRB 020124: Optical observations
  3. GRB 020418: Optical observations
  4. IPN triangulation of GRB020418
  5. GRB020405: VLT observations of the OT environment
  6. IPN triangulation of GRB020413
  7. GRB 020409: No Evidence for an Optical Afterglow
  8. GRB 020331 Kyoto observation on March 31
  9. X-ray afterglow of GRB020321
  10. GRB020405: VLT optical observations and V band decay slope
  11. GRB020331 optical observations with RIMOTS
  12. GRB020124 optical observations with RIBOTS/RIMOTS
  13. GRB 020321: Candidate X-ray Counterparts
  14. ASM GRB candidate 020406 refined error box
  15. GRB020406(?), optical observations
  16. GRB020405: VLT optical observations
  17. GRB020405, Radio Observations
  18. GRB 020405, U-band observations
  19. IPN localization of GRB020405
  20. GRB011212: Optical Observations
  21. GRB020331 NIR observation at KPNO (re-submission)
  22. GRB02033 NIR observation at KPNO
  23. GRB020331 field photometry
  24. GRB 020331 Optical Observations
  25. GRB 020331, NIR observations
  26. GRB 020321: Infrared observations
  27. GRB 020322: BeppoSAX observations of the X-ray afterglow
  28. GRB011211: HST Observations of Optical Afterglow and Host Galaxy
  29. GRB 020322, Radio observations
  30. Near-Infrared Observations of GRB020322 at TIRGO
  31. GRB 020322: Optical Observations
  32. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  33. GRB 020321: Optical observations
  34. GRB020317 BVRI field photometry
  35. GRB011211 revised BVRI field photometry
  36. GRB020305 BVRI field photometry
  37. GRB020322 BVRI field photometry
  38. GRB020317 : Near IR Observations from Mt Abu Observatory
  39. GRB 020322: Optical Sources and Improved Astrometry
  40. Bepposax GRB020322 The second springtime BSAX GRB
  41. GRB020317: optical observations
  42. GRB020321 optical observations
  43. GRB020321: a faint BeppoSAX detection
  44. GRB 020317 : KISO Optical Observations
  45. GRB 020305: Optical Observations
  46. GRB020317, optical observations
  47. GRB 020317: Optical observations
  48. GRB 011121: Third HST Epoch
  49. GRB020305: Properties of the Candidate Optical Afterglow
  50. GRB 011121: HST Observations reveal an intermediate-time multicolor
  51. GRB011130 (XRF011130) Second Epoch Chandra Observations
  52. XRF/GRB 011030: Detection of the Probable Host Galaxy
  53. GRB020305, optical observations
  54. IPN triangulation of GRB020305 (HETE 1939)
  55. GRB020305 (=H1939): Localization of a GRB by HETE
  56. HST Imaging of the afterglow and host of GRB 011121
  57. GRB020127: Further VLA Observations of Possible Counterparts
  58. SGR1900+14 activity
  59. IPN Upper Limits to a GRB Associated With SN2002ap
  60. GRB020124 BVRI field photometry
  61. GRB020127: Palomar and VLA Observations of Possible Counterparts
  62. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  63. SN2002ap (SN/GRB?) Echelle spectra
  64. GRB020127, WSRT radio observations
  65. GRB020127 Optical Observations
  66. SN 2002ap in M74
  67. SN2002ap (SN/GRB?) UBVRI Field Photometry
  68. GRB020127: Chandra Observations and Prospective Counterparts
  69. pre-SN2002ap (SN/GRB?) imaging of M74
  70. GRB020124, optical observations
  71. GRB020127: Optical observations
  72. GRB 020127, I-band observations starting 3.14-hr after the event
  73. IPN triangulation of GRB020127 (=H1902)
  74. GRB010921 Optical Observations
  75. GRB020124: Optical observations
  76. GRB 020124: Optical observations
  77. IPN triangulation of GRB020124 (HETE 1896)
  78. GRB020124(=H1896): Localization of a Long GRB by HETE
  79. Possible optical counterpart to a GRB
  80. GRB011212, Optical Observations
  81. Optical polarization observations for GRB011211
  82. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  83. GRB 011130: Optical Observations of X-ray and Radio Sources
  84. GRB 011130, Radio/X-ray Comparison
  85. GRB 011212: optical observation at Asiago
  86. GRB 011211: Evidence for an Optical Break
  87. GRB 011212: optical observation at Oslo (relayed)
  88. GRB 011211, Optical Observations
  89. GRB011212, BVRI field photometry
  90. GRB011211, BVRI field photometry
  91. Fading of the optical source associated of XRF 011211
  92. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  93. GRB011130 (XRF011130) Chandra Observations
  94. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  95. GRB 011130, K band observations
  96. GRB011130, optical observations
  97. GRB011130 (XRF011130) SDSS PT i-band observations
  98. XRF011130: Infrared Observations
  99. GRB011130 (=XRF011130), Optical Observations
  100. GRB 011121

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